Patent Publication Number: US-2021171316-A1

Title: Energy-saving elevator

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of priority from pending U.S. Provisional Patent Application Ser. No. 62/966,564, filed on Jan. 28, 2020, and entitled “REDUCING POWER CONSUMPTION IN AN ELEVATOR” which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to energy-saving systems, and particularly relates to energy saving in an elevator. The present disclosure more particularly relates to an energy-saving traction-type elevator. 
     BACKGROUND 
     During operation of an elevator, such as a traction-type elevator, the elevator may carry approximately the same mass upward and downward, and in terms of energy conservation, a power loss of an elevator may only lead to friction heating. In terms of mechanical energy, an elevator may be in an ideal status if the elevator car (load) is equal to a counterweight. Usually, a ratio of a counterweight to a car weight may be 1.5:1. However, a load may vary frequently, so it may be difficult for an elevator to get in the ideal status of weight to counterweight ratio. 
     A function of a counterbalance system of an elevator may be to drive a counterbalance unit and a car (load) to reach relative balance. During operation of an elevator, the elevator may make sure that a difference between a counterbalance unit and a car (load) stays at a such small value that the elevator is in a relative ideal status even if the load changes. On the contrary, if a counterbalance unit and a car of an elevator have a weight difference greater than a specific amount, the working of the elevator may inevitably result in accumulation and release of mechanical potential energy, thereby causing waste of energy. 
     Currently, various energy-saving traction-type elevators with a variable counterbalancing mass are available. In these energy-saving traction-type elevators, a mass of a counterbalance unit may vary by assembling and dismantling a counterbalance unit. However, these elevators may have some drawbacks. For example, existing variable counterbalancing elevators may reduce a drive moment and power of a traction machine and fulfill the aim of saving energy by decreasing a weight difference between a counterbalance unit and a car of an elevator by assembling and/or dismantling the counterbalance unit. However, the assembling and/or dismantling of the counterbalance unit may inevitably result in power loss. For example, if a weight of a car of an elevator changes significantly, many counterbalance units have to be assembled and/or dismantled which may lead to waste of time. There is, therefore, a need for an energy-saving elevator which has a simple and rational structure and is able to effectively realize elevator energy saving. 
     SUMMARY 
     This summary is intended to provide an overview of the subject matter of the present disclosure, and is not intended to identify essential elements or key elements of the subject matter, nor is it intended to be used to determine the scope of the claimed implementations. The proper scope of the present disclosure may be ascertained from the claims set forth below in view of the detailed description below and the drawings. 
     In one general aspect, the present disclosure describes an exemplary energy-saving elevator. In an exemplary embodiment, an exemplary energy-saving elevator may include an elevator, a counterweight, a lift cable, and a hoist-type lifting mechanism. In an exemplary embodiment, the lift cable may be interconnected between the elevator car and the counterweight. In an exemplary embodiment, a first end of the lift cable may be connected to the elevator car. In an exemplary embodiment, a second end of the lift cable may be connected to the counterweight. 
     In an exemplary embodiment, the lift cable may be connected to the hoist-type lifting mechanism. In an exemplary embodiment, the hoist-type lifting mechanism may include a first adjustable pulley, a second adjustable pulley, and an adjusting cable. In an exemplary embodiment, the hoist-type lifting mechanism may be configured to lift the elevator car by pulling up the first end of the lift cable by rotating the first adjustable pulley in a first rotational direction. 
     In an exemplary embodiment, the hoist-type lifting mechanism may be configured to lift the counterweight by pulling up the second end of the lift cable by rotating the second adjustable pulley in a second rotational direction. In an exemplary embodiment, the adjusting cable may be interconnected between the first adjustable pulley and the second adjustable pulley. In an exemplary embodiment, the first adjustable pulley and the second adjustable pulley may be configured to hold the adjusting cable. 
     In an exemplary embodiment, the first adjustable pulley may include a first fixed conical member and a first moveable conical member. In an exemplary embodiment, the first fixed conical member may include a first conical surface. In an exemplary embodiment, the first moveable conical member may include a second conical surface. 
     In an exemplary embodiment, the first moveable conical member may be configured to move linearly along a first axis. In an exemplary embodiment, the first conical surface and the second conical surface may face each other. In an exemplary embodiment, the first conical surface and the second conical surface may form a first trapezoid-shape groove between the first fixed conical member and the first moveable conical member. In an exemplary embodiment, the first trapezoid-shape groove may be configured to receive the adjusting cable. In an exemplary embodiment, the first conical surface and the second conical surface may be configured to hold the adjusting cable inside the first trapezoid-shape groove. 
     In an exemplary embodiment, the adjusting cable may be configured to move away from the first axis inside the first trapezoid-shape groove responsive to moving the first moveable conical member towards the first fixed conical member along the first axis. In an exemplary embodiment, the adjusting cable may be configured to move towards the first axis inside the first trapezoid-shape groove responsive to moving the first moveable conical member away from the first fixed conical member along the first axis. 
     In an exemplary embodiment, the second adjustable pulley may include a second fixed conical member and a second moveable conical member. In an exemplary embodiment, the second fixed conical member may include a third conical surface. In an exemplary embodiment, the second moveable conical member may include a fourth conical surface. 
     In an exemplary embodiment, the second moveable conical member may be configured to move linearly along a second axis. In an exemplary embodiment, the third conical surface and the fourth conical surface may face each other. In an exemplary embodiment, the third conical surface and the fourth conical surface may form a second trapezoid-shape groove between the second fixed conical member and the second moveable conical member. 
     In an exemplary embodiment, the second trapezoid-shape groove may be configured to receive the adjusting cable. In an exemplary embodiment, the adjusting cable may be configured to move away from the second axis inside the second trapezoid-shape groove responsive to moving the second moveable conical member toward the second fixed conical member along the second axis. In an exemplary embodiment, the adjusting cable may be configured to move toward the second axis inside the second trapezoid-shape groove responsive to moving the second moveable conical member away from the second fixed conical member along the second axis. 
     In an exemplary embodiment, the first conical surface may be formed by revolving a first inclined line around the first axis. In an exemplary embodiment, the second conical surface may be formed by revolving a second inclined line around the first axis. In an exemplary embodiment, the third conical surface may be formed by revolving a third inclined line around the second axis. In an exemplary embodiment, the fourth conical surface may be formed by revolving a fourth inclined line around the second axis. 
     In an exemplary embodiment, the first conical surface may be bounded between a first smaller circle of the first fixed conical member and a first larger circle of the first fixed conical member. In an exemplary embodiment, a diameter of the first smaller circle may be smaller than a diameter of the first larger circle. In an exemplary embodiment, the second conical surface may be bounded between a second smaller circle of the first moveable conical member and a second larger circle of the first moveable conical member. In an exemplary embodiment, a diameter of the second smaller circle may be smaller than a diameter of the second larger circle. 
     In an exemplary embodiment, the third conical surface may be bounded between a third smaller circle of the second fixed conical member and a third larger circle of the second fixed conical member. In an exemplary embodiment, a diameter of the third smaller circle may be smaller than a diameter of the third larger circle. In an exemplary embodiment, the fourth conical surface may be bounded between a fourth smaller circle of the second moveable conical member and a fourth larger circle of the second moveable conical member. In an exemplary embodiment, a diameter of the fourth smaller circle may be smaller than a diameter of the fourth larger circle. 
     In an exemplary embodiment, the first fixed conical member may include a first front surface. In an exemplary embodiment, the first front surface may include a circular shape. In an exemplary embodiment, an outer circle of the first front surface may coincide with the first smaller circle. In an exemplary embodiment, the first moveable conical member may include a second front surface. In an exemplary embodiment, the second front surface may include a circular shape. In an exemplary embodiment, an outer circle of the second front surface may coincide with the second smaller circle. 
     In an exemplary embodiment, the second fixed conical member may include a third front surface. In an exemplary embodiment, the third front surface may include a circular shape. In an exemplary embodiment, an outer circle of the third front surface may coincide with the third smaller circle. In an exemplary embodiment, the second moveable conical member may include a fourth front surface. In an exemplary embodiment, the fourth front surface may include a circular shape. In an exemplary embodiment, an outer circle of the fourth front surface may coincide with the fourth smaller circle. In an exemplary embodiment, the first front surface may face the second front surface. In an exemplary embodiment, the third front surface may face the fourth front surface. 
     In an exemplary embodiment, the energy-saving elevator may further include a first rod and a second rod. In an exemplary embodiment, a main axis of the first rod main coincide with the first axis. In an exemplary embodiment, the first fixed conical member may be mounted fixedly on the first rod. In an exemplary embodiment, the first moveable conical member may be mounted slidably on the first rod. 
     In an exemplary embodiment, a main axis of the second rod may coincide with the second axis. In an exemplary embodiment, the second fixed conical member may be mounted fixedly. In an exemplary embodiment, the second moveable conical member may be mounted slidably on the second rod. 
     In an exemplary embodiment, the energy-saving elevator may further include a first sheave and a second sheave. In an exemplary embodiment, the first sheave may be mounted on the first rod by utilizing a first idler bearing. In an exemplary embodiment, the first idler bearing may be disposed between the first sheave and the first rod. In an exemplary embodiment, the first idler bearing may be configured to urge the first sheave to rotate around the first axis synchronously with the first rod responsive to clockwise rotation of the first rod around the first axis. In an exemplary embodiment, the first rod may remain stationary responsive to counterclockwise rotation of the first rod around the first axis. 
     In an exemplary embodiment, the second sheave may be mounted on the second rod by utilizing a second idler bearing. In an exemplary embodiment, the second idler bearing may be disposed between the second sheave and the second rod. In an exemplary embodiment, the second idler bearing may be configured to urge the second sheave to rotate around the second axis synchronously with the second rod responsive to counterclockwise rotation of the second rod around the second axis. In an exemplary embodiment, the second rod may remain stationary responsive to clockwise rotation of the second sheave around the second axis. In an exemplary embodiment, the first sheave and the second sheave may be configured to hold the lift cable. In an exemplary embodiment, the lift cable may be wrapped around the first sheave and the second sheave. 
     In an exemplary embodiment, the energy-saving elevator may include a first actuator and a second actuator. In an exemplary embodiment, the first actuator may be attached to the first moveable conical member. In an exemplary embodiment, the first actuator may be configured to move the first moveable conical member along the first axis. In an exemplary embodiment, the second actuator may be attached to the second moveable conical member. In an exemplary embodiment, the second actuator may be configured to move the second moveable conical member along the second axis. 
     In an exemplary embodiment, the first adjustable pulley may be configured to rotate around the first axis. In an exemplary embodiment, the second adjustable pulley may be configured to rotate around the second axis. In an exemplary embodiment, the first axis may be parallel to the second axis. In an exemplary embodiment, the energy-saving elevator may further include an electromotor. In an exemplary embodiment, the electromotor may be configured to rotate the first adjustable pulley around the first axis and rotate the second adjustable pulley around the second axis. 
     In an exemplary embodiment, the electromotor may include a drive gear. In an exemplary embodiment, the drive gear configured to move along a third axis, the third axis parallel to the first axis and the second axis. 
     In an exemplary embodiment, the energy-saving elevator may further include a first gear and a second gear. In an exemplary embodiment, the first gear may be connected to the first adjustable pulley. In an exemplary embodiment, the electromotor may be configured to be engaged with the first gear responsive to the drive gear being in a first position along the third axis. In an exemplary embodiment, the second gear may be connected to the second adjustable pulley. In an exemplary embodiment, the electromotor may be configured to be engaged with the second gear responsive to the drive gear being in a second position along the third axis. 
     In an exemplary embodiment, the electromotor may be configured to rotate the first adjustable pulley around the first axis responsive to the electromotor being engaged with the first gear. In an exemplary embodiment, the electromotor may be configured to rotate the second adjustable pulley around the second axis responsive to the electromotor being engaged with the second gear. 
     In an exemplary embodiment, the energy-saving elevator may further include a first weight sensor and a second weight sensor. In an exemplary embodiment, the first weight sensor may be associated with the elevator car. In an exemplary embodiment, the first weight sensor may be configured to measure a weight of the elevator car. In an exemplary embodiment, the second weight sensor may be associated with the counterweight. In an exemplary embodiment, the second weight sensor may be configured to measure a weight of the counterweight. 
     In an exemplary embodiment, the energy-saving elevator may further include one or more processors. In an exemplary embodiment, the one or more processors may be configured to receive a first set of data associated with the weight of the elevator car from the first weight sensor, receive a second set of data associated with the weight of the counterweight from the second weight sensor, control the first actuator and the second actuator based on the first set of data and the second set of data, and control a position of the electromotor along the third axis based on the first set of data and the second set of data. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawing figures depict one or more implementations in accord with the present teachings, by way of example only, not by way of limitation. In the figures, like reference numerals refer to the same or similar elements. 
         FIG. 1A  illustrates a perspective view of an exemplary energy-saving elevator, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 1B  illustrates an exploded view of an energy-saving elevator, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 2A  illustrates a first adjustable pulley, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 2B  illustrates a side view of a first adjustable pulley, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 3A  illustrates a second adjustable pulley, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 3B  illustrates a side view of a second adjustable pulley, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 3C  illustrates a perspective view of a first sheave and a second sheave when an adjustable cable is inserted into a first trapezoid-shape groove and a second trapezoid-shape groove, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 3D  illustrates a side view and a top view of a first sheave, a second sheave, and an adjustable cable in a first scenario in which a first moveable conical member is close to a first fixed conical member and a second moveable conical member is far from a second fixed conical member, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 3E  shows a side view and a top view of first sheave, second sheave, and adjustable cable in a second scenario in which first moveable conical member is relatively far from first fixed conical member and second moveable conical member is relatively close to second fixed conical member, consistent with one or more exemplary embodiments. 
         FIG. 4A  illustrates a top view of an energy-saving elevator, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 4B  illustrates a top view of an energy-saving elevator in a scenario in which a drive gear is engaged with a first gear, consistent with one or more exemplary embodiments of the present disclosure. 
         FIG. 5  illustrates an example computer system in which an embodiment of the present disclosure, or portions thereof, may be implemented as computer-readable code, consistent with exemplary embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant teachings. However, it should be apparent that the present teachings may be practiced without such details. In other instances, well known methods, procedures, components, and/or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings. 
     The following detailed description is presented to enable a person skilled in the art to make and use the methods and devices disclosed in exemplary embodiments of the present disclosure. For purposes of explanation, specific nomenclature is set forth to provide a thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that these specific details are not required to practice the disclosed exemplary embodiments. Descriptions of specific exemplary embodiments are provided only as representative examples. Various modifications to the exemplary implementations will be readily apparent to one skilled in the art, and the general principles defined herein may be applied to other implementations and applications without departing from the scope of the present disclosure. The present disclosure is not intended to be limited to the implementations shown, but is to be accorded the widest possible scope consistent with the principles and features disclosed herein. 
     Herein is disclosed an exemplary energy-saving elevator. An exemplary energy-saving elevator may include an elevator car with a first adjustable pulley, a counterweight with a second adjustable pulley, and an electromotor. The electromotor may rotate the first adjustable pulley and/or the second adjustable pulley to raise and/or lower the elevator car and the counterweight. The first adjustable pulley may include a first moveable conical member and a first fixed conical member which may form a first trapezoid-shaped groove between the first moveable conical member and the first fixed conical member. The second adjustable pulley may include a second moveable conical member and a second fixed conical member which may form a second trapezoid-shaped groove between the second moveable conical member and the second fixed conical member. The first adjustable pulley and the second adjustable pulley may hold an adjustable cable in the first trapezoid-shaped groove and the second trapezoid-shaped groove. 
     By moving the first moveable conical member toward or away from the first fixed conical member, a rotation radius of the adjustable cable inside the first trapezoid-shaped groove may increase or decrease. Also, by moving the second moveable conical member toward or away from the second fixed conical member, a rotation radius of the adjustable cable inside the second trapezoid-shaped groove may increase or decrease. Depending on a weight of the elevator car and a weight of the counterweight, a user may adjust a rotation radius of the adjustable cable inside the first trapezoid-shaped groove and a rotation radius of the adjustable cable inside the second trapezoid-shaped groove to reduce the energy consumption by the electromotor to raise and/or lower the elevator car. A user may adjust a rotation radius of the adjustable cable inside the first trapezoid-shaped groove by moving the first moveable conical member toward or away from the first fixed conical member. A user may also adjust a rotation radius of the adjustable cable inside the second trapezoid-shaped groove by moving the second moveable conical member toward or away from the second fixed conical member. 
       FIG. 1A  shows a perspective view of an exemplary energy-saving elevator  100 , consistent with one or more exemplary embodiments of the present disclosure.  FIG. 1B  shows an exploded view of energy-saving elevator  100 , consistent with one or more exemplary embodiments of the present disclosure. As shown in  FIG. 1A  and  FIG. 1B , in an exemplary embodiment, energy-saving elevator  100  may include an elevator car  102  and a counterweight  104 . In an exemplary embodiment, elevator car  102  and counterweight  104  may be connected to each other by utilizing a lift cable  106 . In an exemplary embodiment, a first end  162  of lift cable  106  may be attached to elevator car  102 . In an exemplary embodiment, a second end  164  of lift cable  106  may be attached to elevator car  102 . In an exemplary embodiment, energy-saving elevator  100  may further include a first sheave  103  and a second sheave  105 . In an exemplary embodiment, first sheave  103  and second sheave  105  may hold lift cable  106 . In an exemplary embodiment, first sheave  103  may be mounted on a first rod  137 . In an exemplary embodiment, first sheave  103  may be configured to rotate around a first axis  136 . In an exemplary embodiment, first sheave  103  may be mounted on first rod  137 . In an exemplary embodiment, first sheave  103  may be mounted on first rod  137  by utilizing a first idler bearing  1372 . In an exemplary embodiment, first idler bearing  1372  may be disposed between first sheave  103  and first rod  137 . In an exemplary embodiment, when first rod  137  rotates around first axis  136  in a clockwise direction, first idler bearing  1372  may urge first sheave  103  to rotate synchronously with first rod  137  around first axis  136 . In an exemplary embodiment, synchronous rotation of a first element with a second element, may refer to a rotation of the first element with a same rotational speed and in a same direction as a rotation of the second element. In an exemplary embodiment, when first sheave  103  rotates around first axis  136  in a counterclockwise direction, first idler bearing  1372  may not urge first rod  137  to rotate. In an exemplary embodiment, second sheave  105  may be mounted on a second rod  157 . In an exemplary embodiment, second sheave  105  may be configured to rotate around a second axis  156 . In an exemplary embodiment, second sheave  105  may be mounted on second rod  157 . In an exemplary embodiment, second sheave  105  may be mounted on second rod  157  by utilizing a second idler bearing  1572 . In an exemplary embodiment, second idler bearing  1572  may be disposed between second sheave  105  and second rod  157 . In an exemplary embodiment, when second rod  157  rotates around second axis  156  in a counterclockwise direction, second idler bearing  1572  may urge second sheave  105  to rotate synchronously with second rod  157  around second axis  136 . In an exemplary embodiment, when second sheave  105  rotates around second axis  156  in a clockwise direction, second idler bearing  1572  may not urge second rod  157  to rotate. In an exemplary embodiment, first axis  136  and second axis  156  may be parallel to each other. In an exemplary embodiment, lift cable  106  may be wound around first sheave  103  and second sheave  105 . In an exemplary embodiment, when first sheave  103  and second sheave  105  rotate, friction forces between a grooved surface of first sheave  103  and lift cable  106  and also friction forces between a grooved surface of second sheave  105  and lift cable  106  may move lift cable  106  and, thereby, may cause elevator car  102  and counterweight  104  to raise and/or lower in opposite directions. In an exemplary embodiment, when first sheave  103  and second sheave  105  rotate in a first rotational direction  132 , elevator car  102  may be raised and counterweight  104  may be lowered. In an exemplary embodiment, when first sheave  103  and second sheave  105  rotate in a second rotational direction  134 , elevator car  102  may be lowered and counterweight  104  may be raised. In an exemplary embodiment, first rotational direction  132  may refer to a counterclockwise direction and second rotational direction  134  may refer to a clockwise direction. 
     In an exemplary embodiment, energy-saving elevator  100  may further include an electromotor  107 . In an exemplary embodiment, electromotor  107  may be configured to be connected to first sheave  103  and/or second sheave  105 . In an exemplary embodiment, electromotor  107  may cause first sheave  103  to rotate around first axis  136 . In an exemplary embodiment, electromotor  107  may cause second sheave  105  to rotate around second axis  156 . In an exemplary embodiment, when elevator car  102  is intended to be raised, electromotor  107  may cause first sheave  103  to rotate around first axis  136  in first rotational direction  132  and cause second sheave  105  to rotate around second axis  156  in first rotational direction  132 . In an exemplary embodiment, when elevator car  102  is intended to be lowered, electromotor  107  may cause first sheave  103  to rotate around first axis  136  in second rotational direction  134  and cause second sheave  105  to rotate around second axis  156  in second rotational direction  132 . In an exemplary embodiment, elevator car  102  may refer to a compartment which may be configured to carry people and/or freight from floor to floor in a building. It also may be understood that a total weight of elevator car  102  may depend on people and/or freight that elevator car  102  carries. 
     In an exemplary embodiment, energy-saving elevator  100  may further include a first adjustable pulley  108  and a second adjustable pulley  109 .  FIG. 2A  shows first adjustable pulley  108 , consistent with one or more exemplary embodiments of the present disclosure.  FIG. 2B  shows a side view of first adjustable pulley  108 , consistent with one or more exemplary embodiments of the present disclosure. As shown in  FIG. 2A  and  FIG. 2B , in an exemplary embodiment, first adjustable pulley  108  may include a first fixed conical member  202  and a first moveable conical member  204 . In an exemplary embodiment, first fixed conical member  202  may be mounted fixedly on first rod  137 . In an exemplary embodiment, when first fixed conical member  202  is mounted fixedly on first rod  137 , it may mean that first fixed conical member  202  is mounted on first rod  137  in such a way that any relative movement between first fixed conical member  202  and first rod  137  may be prevented. In an exemplary embodiment, first fixed conical member  202  may include a first rod receiving hole  222 . In an exemplary embodiment, in order to mount first fixed conical member  202  on first rod  137 , first rod  137  may be inserted into first rod receiving hole  222 . In an exemplary embodiment, first rod  137  may be tightly fitted inside first rod receiving hole  222  to prevent any relative movement between first fixed conical member  202  and first rod  137 . 
     In an exemplary embodiment, first moveable conical member  204  may be mounted slidably on first rod  137 . In an exemplary embodiment, when first moveable conical member  204  is mounted slidably on first rod  137 , it may mean that first moveable conical member  204  is mounted on first rod  137  in such a way that first moveable conical member  204  may be able to move linearly along first axis  136 . In an exemplary embodiment, first moveable conical member  204  may include a second rod receiving hole  242 . In an exemplary embodiment, in order to mount first moveable conical member  204  on first rod  137 , first rod  137  may be inserted into second rod receiving hole  242 . In an exemplary embodiment, first rod  137  may be loosely fitted inside second rod receiving hole  242  to allow linear movement of first moveable conical member  204  along first axis  136 . In an exemplary embodiment, an inner diameter of second rod receiving hole  242  may be slightly larger than an outer diameter of first rod  137 . For example, the inner diameter of second rod receiving hole  242  may be larger than the outer diameter of first rod  137  by the amount of 1 mm. 
     In an exemplary embodiment, first fixed conical member  202  may include a first conical surface  224 . In an exemplary embodiment, first conical surface  224  may be formed by revolving a first inclined line  2242  around first axis  136 . In an exemplary embodiment, first conical surface  224  may be bounded between a first smaller circle  2244  and a first larger circle  2246 . In an exemplary embodiment, a diameter of first smaller circle  2244  may be smaller than a diameter of first larger circle  2246 . In an exemplary embodiment, first moveable conical member  204  may include a second conical surface  244 . In an exemplary embodiment, second conical surface  244  may be formed by revolving a second inclined line  2442  around first axis  136 . In an exemplary embodiment, second conical surface  244  may be bounded between a second smaller circle  2444  and a second larger circle  2446 . In an exemplary embodiment, a diameter of second smaller circle  2444  may be smaller than a diameter of second larger circle  2446 . In an exemplary embodiment, first fixed conical member  202  and first moveable conical member  204  may be mounted on first rod  137  in such a way that first conical surface  224  and second conical surface  244  face each other. In an exemplary embodiment, first conical surface  224  and second conical surface  244  may form a first trapezoid-shape groove  234  between first fixed conical member  202  and first moveable conical member  204 . In an exemplary embodiment, first trapezoid-shape groove  234  may be configured to receive an adjusting cable  101 . In an exemplary embodiment, receiving adjusting cable  101  by first trapezoid-shape groove  234  may refer to inserting adjusting cable  101  into first trapezoid-shape groove  234 . In an exemplary embodiment, adjusting cable  101  may be disposed inside first trapezoid-shape groove  234 . In an exemplary embodiment, adjusting cable  101  may be inserted into first trapezoid-shape groove  234 . In an exemplary embodiment, first conical surface  224  and second conical surface  244  may hold adjusting cable  101  inside first trapezoid-shape groove  234 . 
       FIG. 3A  shows second adjustable pulley  109 , consistent with one or more exemplary embodiments of the present disclosure.  FIG. 3B  shows a side view of second adjustable pulley  109 , consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, first adjustable pulley  108  and second adjustable pulley  109  may be coupled to each other by utilizing adjusting cable  101 . In an exemplary embodiment, second adjustable pulley  109  may be substantially similar to first adjustable pulley  108  in structure and function. As shown in  FIG. 3A  and  FIG. 3B , in an exemplary embodiment, second adjustable pulley  109  may include a second fixed conical member  302  and a second moveable conical member  304 . In an exemplary embodiment, second fixed conical member  302  may be mounted fixedly on second rod  157 . In an exemplary embodiment, when second fixed conical member  302  is mounted fixedly on second rod  157 , it may mean that second fixed conical member  302  is mounted on second rod  157  in such a way that any relative movement between second fixed conical member  302  and second rod  157  may be prevented. In an exemplary embodiment, second fixed conical member  302  may include a third rod receiving hole  322 . In an exemplary embodiment, in order to mount second fixed conical member  302  on second rod  157 , second rod  157  may be inserted into third rod receiving hole  322 . In an exemplary embodiment, second rod  157  may be tightly fitted inside third rod receiving hole  322  to prevent any relative movement between second fixed conical member  302  and second rod  157 . 
     In an exemplary embodiment, second moveable conical member  304  may be mounted slidably on second rod  157 . In an exemplary embodiment, when second moveable conical member  304  is mounted slidably on second rod  157 , it may mean that second moveable conical member  304  is mounted on second rod  157  in such a way that second moveable conical member  304  may be able to move linearly along second axis  156 . In an exemplary embodiment, second moveable conical member  304  may include a fourth rod receiving hole  342 . In an exemplary embodiment, in order to mount second moveable conical member  304  on second rod  157 , second rod  157  may be inserted into fourth rod receiving hole  342 . In an exemplary embodiment, second rod  157  may be loosely fitted inside fourth rod receiving hole  342  to allow linear movement of second moveable conical member  304  along second axis  156 . In an exemplary embodiment, an inner diameter of fourth rod receiving hole  342  may be slightly larger than an outer diameter of second rod  157 . For example, the inner diameter of fourth rod receiving hole  342  may be larger than the outer diameter of second rod  157  by the amount of 1 mm. 
     In an exemplary embodiment, second fixed conical member  302  may include a third conical surface  324 . In an exemplary embodiment, third conical surface  324  may be formed by revolving a third inclined line  3242  around second axis  156 . In an exemplary embodiment, third conical surface  324  may be bounded between a third smaller circle  3244  and a third larger circle  3246 . In an exemplary embodiment, a diameter of third smaller circle  3244  may be smaller than a diameter of third larger circle  3246 . In an exemplary embodiment, second moveable conical member  304  may include a fourth conical surface  344 . In an exemplary embodiment, fourth conical surface  344  may be formed by revolving a fourth inclined line  3442  around second axis  156 . In an exemplary embodiment, fourth conical surface  344  may be bounded between a fourth smaller circle  3444  and a fourth larger circle  3446 . In an exemplary embodiment, a diameter of fourth smaller circle  3444  may be smaller than a diameter of fourth larger circle  3446 . In an exemplary embodiment, second fixed conical member  302  and second moveable conical member  304  may be mounted on second rod  157  in such a way that third conical surface  324  and fourth conical surface  344  face each other. In an exemplary embodiment, third conical surface  324  and fourth conical surface  344  may form a second trapezoid-shape groove  334  between second fixed conical member  302  and second moveable conical member  304 . In an exemplary embodiment, second trapezoid-shape groove  334  may be configured to receive adjusting cable  101 . In an exemplary embodiment, receiving adjusting cable  101  by second trapezoid-shape groove  334  may refer to inserting adjusting cable  101  into second trapezoid-shape groove  334 . In an exemplary embodiment, adjusting cable  101  may be disposed inside second trapezoid-shape groove  334 . In an exemplary embodiment, adjusting cable  101  may be inserted into second trapezoid-shape groove  334 . In an exemplary embodiment, third conical surface  324  and fourth conical surface  344  may hold adjusting cable  101  inside second trapezoid-shape groove  334 . 
       FIG. 3C  shows a perspective view of first sheave  103  and second sheave  105  when adjustable cable  101  is inserted into first trapezoid-shape groove  234  and second trapezoid-shape groove  334 , consistent with one or more exemplary embodiments of the present disclosure. Referring to  FIG. 2B , in an exemplary embodiment, when first moveable conical member  204  moves away from first fixed conical member  202  and along first axis  136 , adjustable cable  101  may move toward first axis  136  inside first trapezoid-shape groove  234 . In an exemplary embodiment, it may be understood that when first moveable conical member  204  moves away from first fixed conical member  202 , first conical surface  224  and second conical surface  244  may become further from each other and, to thereby, may urge adjustable cable  101  to move toward first axis  136  inside first trapezoid-shape groove  234 . In an exemplary embodiment, when first moveable conical member  204  moves toward first fixed conical member  202  and along first axis  136 , adjustable cable  101  may move away from first axis  136  inside first trapezoid-shape groove  234 . In an exemplary embodiment, it may be understood that when first moveable conical member  204  moves toward first fixed conical member  202 , first conical surface  224  and second conical surface  244  may become closer to each other and, to thereby, may urge adjustable cable  101  to move away from first axis  136  inside first trapezoid-shape groove  234 . 
     Referring to  FIG. 3B , in an exemplary embodiment, when second moveable conical member  304  moves away from second fixed conical member  302  and along second axis  156 , adjustable cable  101  may move toward second axis  156  inside second trapezoid-shape groove  334 . In an exemplary embodiment, it may be understood that when second moveable conical member  304  moves away from second fixed conical member  302 , third conical surface  324  and fourth conical surface  344  may become closer to each other and, to thereby, may urge adjustable cable  101  to move toward second axis  156  inside second trapezoid-shape groove  334 . In an exemplary embodiment, when second moveable conical member  304  moves toward second fixed conical member  302  and along second axis  156 , adjustable cable  101  may move away from second axis  156  inside second trapezoid-shape groove  334 . In an exemplary embodiment, it may be understood that when second moveable conical member  304  moves toward second fixed conical member  302 , third conical surface  324  and fourth conical surface  344  may become closer to each other and, to thereby, may urge adjustable cable  101  to move away from second axis  156  inside second trapezoid-shape groove  334 . 
       FIG. 3D  shows a side view and a top view of first sheave  103 , second sheave  105 , and adjustable cable  101  in a first scenario in which first moveable conical member  204  is relatively close to first fixed conical member  202  and second moveable conical member  304  is relatively far from second fixed conical member  302 , consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, first radius  112  may depend on closeness of first moveable conical member  204  to first fixed conical member  202 . In an exemplary embodiment, first radius  112  may refer to a distance between first axis  136  and adjustable cable  101  as shown in  FIG. 3D . In an exemplary embodiment, second radius  114  may depend on closeness of second moveable conical member  304  and second fixed conical member  302 . In an exemplary embodiment, second radius  114  may refer to a distance between second axis  156  and adjustable cable  101  as shown in  FIG. 3D . In an exemplary embodiment, in the first scenario, first radius  112  may be greater than second radius  114 .  FIG. 3E  shows a side view and a top view of first sheave  103 , second sheave  105 , and adjustable cable  101  in a second scenario in which first moveable conical member  204  is relatively far from first fixed conical member  202  and second moveable conical member  304  is relatively close to second fixed conical member  302 . In an exemplary embodiment, in the second scenario, second radius  114  may be greater than first radius  112 . 
     As further shown in  FIG. 1A  and  FIG. 1B , in an exemplary embodiment, energy-saving elevator  100  may further include a first actuator  182  and a second actuator  192 . In an exemplary embodiment, first actuator  182  may be attached to first moveable conical member  204 . In an exemplary embodiment, first actuator  182  may be configured to move first moveable conical member  204  along first axis  136 . In an exemplary embodiment, first actuator  182  may move first moveable conical member  204  along first axis  136  to increase and/or decrease a distance between first moveable conical member  204  and first fixed conical member  202 . In an exemplary embodiment, first actuator  182  may decrease a distance between first moveable conical member  204  and first fixed conical member  202  by moving first moveable conical member  204  along first axis  136  and in a first direction. In an exemplary embodiment, first actuator  182  may increase a distance between first moveable conical member  204  and first fixed conical member  202  by moving first moveable conical member  204  along first axis  136  and in a second direction. In an exemplary embodiment, second actuator  192  may be attached to second moveable conical member  304 . In an exemplary embodiment, second actuator  192  may be configured to move second moveable conical member  304  along second axis  156 . In an exemplary embodiment, second actuator  192  may move second moveable conical member  304  along second axis  156  to increase and/or decrease a distance between second moveable conical member  304  and second fixed conical member  302 . In an exemplary embodiment, second actuator  192  may decrease a distance between second moveable conical member  304  and second fixed conical member  302  by moving second moveable conical member  304  along second axis  156  and in a first direction. In an exemplary embodiment, second actuator  192  may increase a distance between second moveable conical member  304  and second fixed conical member  302  by moving second moveable conical member  304  along second axis  156  and in a second direction. 
     As further shown in  FIG. 1A  and  FIG. 1B , in an exemplary embodiment, energy-saving elevator  100  may further include a first gear  172  and a second gear  174 . In an exemplary embodiment, first gear  172  may be connected to first adjustable pulley  108  through first rod  137 . In an exemplary embodiment, second gear  174  may be connected to second adjustable pulley  109  through second rod  157 . In an exemplary embodiment, electromotor  107  may be configured to be connected to first gear  172  and/or second gear  174 . In an exemplary embodiment, electromotor  107  may include a drive gear  176  which may be configured to be engaged with first gear  172  and/or second gear  174 . 
       FIG. 4A  shows a top view of energy-saving elevator  100 , consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, drive gear  176  may be configured to be moveable along a third axis  410 . In an exemplary embodiment, drive gear  176  may be connected to a motor that may move drive gear  176  along third axis  410 . 
     In an exemplary embodiment, when drive gear  176  is engaged with first gear  172 , electromotor  107  may rotate first adjustable pulley  108 .  FIG. 4B  shows a top view of energy-saving elevator  100  in a scenario in which drive gear  176  is engaged with first gear  172 , consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, when drive gear  176  is engaged with second gear  174  (as shown in  FIG. 4A ), electromotor  107  may rotate second adjustable pulley  109 . 
     In an exemplary embodiment, energy-saving elevator  100  may include a first weight sensor and a second weight sensor (not shown in Figures). In an exemplary embodiment, the first weight sensor may be configured to measure a weight of car elevator  102 . In an exemplary embodiment, the second weight sensor may be configured to measure a weight of counterweight  104 . In an exemplary embodiment, the first weight sensor and the second weight sensor may include a dynamometer or a load cell. In an exemplary embodiment, energy-saving elevator  100  may further include a processor  420 . In an exemplary embodiment, processor  420  may receive a first set of data associated with the weight of elevator car  102  from the first weight sensor and receive a second set of data associated with the weight of counterweight  104  from the second weight sensor. In an exemplary embodiment, processor  420  may be configured to control movements of first actuator  182 , second actuator  192 , and drive gear  176 . For example, when elevator car  102  is heavier than counterweight  104  and elevator car  102  is intended to be raised, first actuator  182  may move first moveable conical member  204  along first axis  136  and toward first fixed conical member  202  so that first radius  112  may be increased. Furthermore, second actuator  192  may move second moveable conical member  304  along second axis  156  and away from second fixed conical member  302  so that second radius  114  may be decreased. Additionally, drive gear  176  may be moved to be engaged with first gear  172 . Then, first gear  172  may be rotated in first rotational direction  132  to raise elevator car  102 . 
     The embodiments have been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed. 
       FIG. 5  shows an example computer system  500  in which an embodiment of the present disclosure, or portions thereof, may be implemented as computer-readable code, consistent with exemplary embodiments of the present disclosure. For example, processor  420  may be implemented in computer system  500  using hardware, software, firmware, tangible computer readable media having instructions stored thereon, or a combination thereof and may be implemented in one or more computer systems or other processing systems. 
     If programmable logic is used, such logic may execute on a commercially available processing platform or a special purpose device. One ordinary skill in the art may appreciate that an embodiment of the disclosed subject matter can be practiced with various computer system configurations, including multi-core multiprocessor systems, minicomputers, mainframe computers, computers linked or clustered with distributed functions, as well as pervasive or miniature computers that may be embedded into virtually any device. 
     For instance, a computing device having at least one processor device and a memory may be used to implement the above-described embodiments. A processor device may be a single processor, a plurality of processors, or combinations thereof. Processor devices may have one or more processor “cores.” 
     An embodiment of the disclosure is described in terms of this example computer system  500 . After reading this description, it will become apparent to a person skilled in the relevant art how to implement the disclosure using other computer systems and/or computer architectures. Although operations may be described as a sequential process, some of the operations may in fact be performed in parallel, concurrently, and/or in a distributed environment, and with program code stored locally or remotely for access by single or multi-processor machines. In addition, in some embodiments the order of operations may be rearranged without departing from the spirit of the disclosed subject matter. 
     Processor device  504  may be a special purpose or a general-purpose processor device. As will be appreciated by persons skilled in the relevant art, processor device  504  may also be a single processor in a multi-core/multiprocessor system, such system operating alone, or in a cluster of computing devices operating in a cluster or server farm. Processor device  504  may be connected to a communication infrastructure  506 , for example, a bus, message queue, network, or multi-core message-passing scheme. 
     In an exemplary embodiment, computer system  500  may include a display interface  502 , for example a video connector, to transfer data to a display unit  530 , for example, a monitor. Computer system  500  may also include a main memory  508 , for example, random access memory (RAM), and may also include a secondary memory  510 . Secondary memory  510  may include, for example, a hard disk drive  512 , and a removable storage drive  514 . Removable storage drive  514  may include a floppy disk drive, a magnetic tape drive, an optical disk drive, a flash memory, or the like. Removable storage drive  514  may read from and/or write to a removable storage unit  518  in a well-known manner. Removable storage unit  518  may include a floppy disk, a magnetic tape, an optical disk, etc., which may be read by and written to by removable storage drive  514 . As will be appreciated by persons skilled in the relevant art, removable storage unit  518  may include a computer usable storage medium having stored therein computer software and/or data. 
     In alternative implementations, secondary memory  510  may include other similar means for allowing computer programs or other instructions to be loaded into computer system  500 . Such means may include, for example, a removable storage unit  522  and an interface  520 . Examples of such means may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or PROM) and associated socket, and other removable storage units  522  and interfaces  520  which allow software and data to be transferred from removable storage unit  522  to computer system  500 . 
     Computer system  500  may also include a communications interface  524 . Communications interface  524  allows software and data to be transferred between computer system  500  and external devices. Communications interface  524  may include a modem, a network interface (such as an Ethernet card), a communications port, a PCMCIA slot and card, or the like. Software and data transferred via communications interface  524  may be in the form of signals, which may be electronic, electromagnetic, optical, or other signals capable of being received by communications interface  524 . These signals may be provided to communications interface  524  via a communications path  526 . Communications path  526  carries signals and may be implemented using wire or cable, fiber optics, a phone line, a cellular phone link, an RF link or other communications channels. 
     In this document, the terms “computer program medium” and “computer usable medium” are used to generally refer to media such as removable storage unit  518 , removable storage unit  522 , and a hard disk installed in hard disk drive  512 . Computer program medium and computer usable medium may also refer to memories, such as main memory  508  and secondary memory  510 , which may be memory semiconductors (e.g. DRAMs, etc.). 
     Computer programs (also called computer control logic) are stored in main memory  508  and/or secondary memory  510 . Computer programs may also be received via communications interface  524 . Such computer programs, when executed, enable computer system  500  to implement different embodiments of the present disclosure as discussed herein. In particular, the computer programs, when executed, enable processor device  504  to implement the processes of the present disclosure. Accordingly, such computer programs represent controllers of computer system  500 . Where an exemplary embodiment of method  100  is implemented using software, the software may be stored in a computer program product and loaded into computer system  500  using removable storage drive  514 , interface  520 , and hard disk drive  512 , or communications interface  524 . 
     Embodiments of the present disclosure also may be directed to computer program products including software stored on any computer useable medium. Such software, when executed in one or more data processing device, causes a data processing device to operate as described herein. An embodiment of the present disclosure may employ any computer useable or readable medium. Examples of computer useable mediums include, but are not limited to, primary storage devices (e.g., any type of random access memory), secondary storage devices (e.g., hard drives, floppy disks, CD ROMS, ZIP disks, tapes, magnetic storage devices, and optical storage devices, MEMS, nanotechnological storage device, etc.). 
     While the foregoing has described what may be considered to be the best mode and/or other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that the teachings may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all applications, modifications and variations that fall within the true scope of the present teachings. 
     Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain. 
     The scope of protection is limited solely by the claims that now follow. That scope is intended and should be interpreted to be as broad as is consistent with the ordinary meaning of the language that is used in the claims when interpreted in light of this specification and the prosecution history that follows and to encompass all structural and functional equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of Sections 101, 102, or 103 of the Patent Act, nor should they be interpreted in such a way. Any unintended embracement of such subject matter is hereby disclaimed. 
     Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims. 
     It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective spaces of inquiry and study except where specific meanings have otherwise been set forth herein. Relational terms such as first and second and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “a” or “an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. 
     The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various implementations. This is for purposes of streamlining the disclosure, and is not to be interpreted as reflecting an intention that the claimed implementations require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed implementation. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter. 
     While various implementations have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more implementations and implementations are possible that are within the scope of the implementations. Although many possible combinations of features are shown in the accompanying figures and discussed in this detailed description, many other combinations of the disclosed features are possible. Any feature of any implementation may be used in combination with or substituted for any other feature or element in any other implementation unless specifically restricted. Therefore, it will be understood that any of the features shown and/or discussed in the present disclosure may be implemented together in any suitable combination. Accordingly, the implementations are not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.