Patent Publication Number: US-9845605-B2

Title: System and method for automatically regulating tensions of guide ropes of flexible cable suspension platform

Description:
RELATED APPLICATIONS 
     The present application is a National Phase entry of PCT Application No. PCT/CN2014/071574, filed Jan. 27, 2014, which claims priority from CN Patent Application No. 201310285331.X, filed Jul. 8, 2013, said applications being hereby incorporated by reference herein in their entirety. 
     FIELD OF THE INVENTION 
     The present invention relates to a system and a method for automatically regulating the tensions of guide ropes, in particular to a system and a method for automatically regulating the tensions of guide ropes of a flexible cable suspension platform applicable to dynamic regulation of the tensions of guide ropes in hanging scaffold systems in vertical shafts. 
     BACKGROUND OF THE INVENTION 
     At present, in most hanging scaffold systems used in construction of vertical shafts, the guide ropes hung on a hanging scaffold are used as guide tracks for lifting a bucket in the vertical shaft. The guide ropes must have certain tensions to ensure lifting the bucket smoothly. However, there are some problems related to the tensions of the guide ropes. For example, the magnitude of the tensions of the guide ropes can not be measured, and can not be regulated conveniently; in addition, the tensions of the guide ropes can not be regulated when they are different from each other. 
     SUMMARY OF THE INVENTION 
     In view of the problems in the prior art, the present invention provides a system and a method for automatically regulating the tensions of guide ropes of a flexible cable suspension platform, which are easy to use, can measure the tensions of the guide ropes, and can regulate the tension conveniently. 
     In one embodiment, the system for automatically regulating the tensions of guide ropes of a flexible cable suspension platform comprises a flexible cable suspension platform, guide ropes, a guide rope winch, suspension ropes, and a suspension rope winch, wherein, the flexible cable suspension platform is provided with a guide rope regulator connected to the lower ends of the guide ropes and a hydraulic pump station connected with the guide rope regulator. 
     The guide rope regulator comprises two conjugated connecting plates, a regulating plate with strip notches arranged between the two conjugated connecting plates, and hydraulic oil cylinders arranged in the strip notches, wherein, the two conjugated connecting plates are provided with a pressing plate on the upper part, a protecting plate on the middle part, and a connecting hole connected to a pin shaft of the flexible cable suspension platform on the lower part respectively, the upper part of the regulating plate is connected with a wedge-shaped rope ring designed to fix the lower end of a guide rope, a cushion block is provided on the bottom of the regulating plate, and the top part of the hydraulic oil cylinder is connected with a bearing block via a connecting hole of the oil cylinder. 
     The hydraulic pump station comprises a hydraulic pump, wherein, a safety valve is arranged at an oil outlet of the hydraulic pump. A two-position two-way directional control valve, a non-return valve, a single-shot booster, and a pressure sensor that are connected to the oil inlets of a plurality of hydraulic oil cylinders respectively are arranged sequentially on the discharge pipeline of the hydraulic pump. A two-position three-way directional control valve is arranged at the oil outlet of the hydraulic oil cylinder, a pilot overflow valve and connecting pipelines designed to connect all hydraulic oil cylinders are arranged at the left oil outlet of the two-position three-way directional control valve. 
     The guide ropes are two or four ropes, arranged in symmetry on the circumference of the flexible cable suspension platform. 
     An embodiment of a method for automatically regulating the tension of guide ropes of a flexible cable suspension platform, which utilizes the system described above, is as follows: 
     When the lifting winch winds up the lifting ropes to drive the lifting container to move along the guide ropes, the guide ropes connected with the flexible cable suspension platform begin to operate, the regulating plate moves up and down between the two connecting plates under the guiding action of the bearing block and the driving action of a piston rod in the hydraulic oil cylinder, so that the guide ropes above the regulating plate are regulated dynamically. The guide ropes apply force on the piston rod in the hydraulic oil cylinder by pulling the regulating plate. The relationship between the tension of the guide ropes and the pressure in the oil chamber of the hydraulic oil cylinder is:
 
 F=P×S  
 
where, F represents the tension of the guide rope, P represents the pressure in the oil chamber of the hydraulic oil cylinder, and S represents the sectional area of the oil chamber of the hydraulic oil cylinder. The pressure in the oil chamber can be measured directly by the pressure sensor, and then the tensions of the guide ropes can be obtained with the above relational expression.
 
     To control the tensions of all guide ropes to the same value, all the two-position three-way valves should be set to the right positions, while all the two-position two-way valves should be set to the left positions, so that all the hydraulic oil cylinders form a closed-loop inter-communicated hydraulic pressure system and the pressure values in all the hydraulic oil cylinders are equal to each other. In that way, the tensions of the guide ropes are regulated dynamically, so that they are balanced automatically. 
     To regulate the tension of a specific guide rope automatically, the two-position three-way directional control valve corresponding to the hydraulic oil cylinder of the guide rope regulator connected to the specific guide rope should be set to the left position, while the corresponding two-position two-way directional control valve should be set to the right position, so that the oil outlet of the hydraulic oil cylinder communicates with the pilot overflow valve, and the tension of the specific guide rope can be fixed to a set value by regulating the pilot overflow valve according to the reading on the pressure sensor connected with the hydraulic oil cylinder. Under the action of the pilot overflow valve, the tension of the guide rope will be regulated by the guide rope regulator, so that the tension of the guide rope is always kept within the range of the set value. 
     With the technical solution described above, the tension of a guide rope can be regulated conveniently by regulating a pilot overflow valve. In addition, the tension of the guide rope can be measured conveniently and accurately by a pressure sensor, and thereby the tension state of the guide rope can be detected conveniently, to ensure the guide ropes have enough tension to effectively limit the swing amplitude during operation of the lifting container. The system is simple and convenient to operate, has a good automatic regulating effect, and thus has wide applicability. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic structural diagram of the system according to an embodiment of the present invention; 
         FIG. 2  is a 3D structural diagram of the guide rope regulator according to an embodiment of the present invention; 
         FIG. 3  is a plan structural diagram of the guide rope regulator according to an embodiment of the present invention; 
         FIG. 4  is a schematic structural diagram of the connecting plate depicted in  FIG. 3 ; 
         FIG. 5  is a schematic structural diagram of the hydraulic oil cylinder depicted in  FIG. 3 ; 
         FIG. 6  is a sectional view A-A of the structure depicted in  FIG. 3 ; 
         FIG. 7  is a sectional view B-B of the structure depicted in  FIG. 3 ; 
         FIG. 8  is a sectional view C-C of the structure depicted in  FIG. 3 ; 
         FIG. 9  is a schematic diagram of the hydraulic system according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     Hereunder the present invention will be further detailed in an embodiment, with reference to the accompanying drawings. 
     The system for automatically regulating the tensions of guide ropes of a flexible cable suspension platform according to an embodiment of the present invention includes a flexible cable suspension platform  1  suspended by suspension ropes  23  wound up by suspension rope winch  24 , and a plurality of guide ropes  2  with one end fixed to the flexible cable suspension platform  1  and the other end fixed to the guide rope winch  12 . The guide ropes  2  are two or four ropes, and the suspension ropes  23  are four ropes, which are evenly distributed on the circumference of the flexible cable suspension platform  1 . The flexible cable suspension platform  1  is provided with a guide rope regulator  3  connected to the lower ends of the guide ropes  2  and a hydraulic pump station  5  connected with the guide rope regulator  3 . 
     The guide rope regulator  3  includes two conjugated connecting plates  11 , a regulating plate  9  with strip notches arranged between the two conjugated connecting plates  11 , and hydraulic oil cylinders  10  arranged in the strip notches of the regulating plate  9 . The two conjugated connecting plates  11  are provided with a pressing plate  16  on the upper part, a protecting plate  14  on the middle part, and a connecting hole  11 - 2  connected to a pin shaft of the flexible cable suspension platform  1  on the lower part respectively. The upper part of the regulating plate  9  is connected with a wedge-shaped rope ring  8  designed to fix the lower end of a guide rope  2 . A cushion block  13  is provided on the bottom of the regulating plate  9 , and the top part of the hydraulic oil cylinder  10  is connected with a bearing block  15  via a connecting hole  10 - 3  of the oil cylinder. 
     The hydraulic pump station  5  includes a hydraulic pump  18 . A safety valve  17  is arranged at an oil outlet of the hydraulic pump  18 , a two-position two-way directional control valve  22 , a non-return valve  19 , a single-shot pressure booster  7 , and a pressure sensor  4  are connected to the oil inlets of a plurality of hydraulic oil cylinders  10  respectively, and are arranged sequentially on the discharge pipeline of the hydraulic pump. A two-position three-way directional control valve  20  is arranged at the oil outlet of the hydraulic oil cylinder  10 . A pilot overflow valve  21  and connecting pipelines  6  designed to connect all the hydraulic oil cylinders  10  are arranged at the left oil outlet of the two-position three-way directional control valve  20 . 
     A method for automatically regulating the tensions of guide ropes of a flexible cable suspension platform provided in an embodiment of the present invention is as follows: 
     When the lifting winch  26  winds up the lifting ropes  25  and drives the lifting container  27  to move along the guide ropes  2 , the guide ropes  2  connected with the flexible cable suspension platform  1  begin to operate. The regulating plate  9  moves up and down between the two connecting plates  11  under the guiding action of the bearing block  15  and the driving action of the piston rod of the hydraulic oil cylinder  10 , so that the guide ropes  2  above the regulating plate  9  are regulated dynamically. The guide ropes  2  apply force on the piston rod of the hydraulic oil cylinder  10  by pulling the regulating plate  9 . The relationship between the tensions of the guide ropes  2  and the pressure in the oil chamber of the hydraulic oil cylinder  10  is as follows:
 
 F=P×S  
 
     where, F represents the tension of the guide rope  2 , P represents the pressure in the oil chamber of the hydraulic oil cylinder  10 , and S represents the sectional area of the oil chamber of the hydraulic oil cylinder  10 . The pressure in the oil chamber can be measured directly by the pressure sensor  4 , and then the tension of the guide rope  2  can be obtained with the above relational expression. 
     To control the tensions of all the guide ropes  2  to the same value, all the two-position three-way valves  20  should be set to the right positions, while all the two-position two-way valves  22  should be set to the left positions, so that all hydraulic oil cylinders  10  form a closed-loop inter-communicated hydraulic pressure system and the pressure values in all the hydraulic oil cylinders  10  are equal to each other. In that way, the tensions of the guide ropes  2  are regulated dynamically, so that they are balanced automatically. 
     To regulate the tension of a specific guide rope  2  automatically, the two-position three-way directional control valve  20  corresponding to the hydraulic oil cylinder  10  of the guide rope regulator  3  connected to the guide rope  2  should be set to the left position, while the corresponding two-position two-way directional control valve  22  should be set to the right position, so that the oil outlet of the hydraulic oil cylinder  10  communicates with the pilot overflow valve  21 , and the tension of the guide rope  2  can be fixed to a set value by regulating the pilot overflow valve  21  according to the reading on the pressure sensor  4  connected with the hydraulic oil cylinder  10 . Under the action of the pilot overflow valve  21 , the tension of the guide rope  2  will be regulated by the guide rope regulator  3  automatically, so that the tension of the guide rope  2  is always kept within the range of the set value. 
     As shown in  FIG. 1 , the flexible cable suspension platform  1  is suspended by four suspension ropes  23  and two guide ropes  2 , and the flexible cable suspension platform  1  is lifted by the suspension ropes  23  wound up by the suspension rope winch  24 . The lifting container  27  is lifted by the lifting ropes  25  wound by the lifting winch  26  along the guide ropes  2 . The lower parts of the guide ropes  2  are connected with the guide rope regulator  3  via the wedge-shaped rope ring  8 . The hydraulic oil cylinders  10  of the guide rope regulator  3  below the two guide ropes  2  are connected with each other through the connecting pipelines  6 . The winding/releasing of the guide ropes  2  is accomplished by means of the guide rope winch  12  on the ground. The hydraulic pump station  5  arranged on the flexible cable suspension platform supplies oil to all the hydraulic oil cylinders  10  on the guide rope regulator  3 . The oil outlets of the hydraulic oil cylinders  10  communicate with each other through the connecting pipelines  6 . Each hydraulic oil cylinder  10  is connected with a pressure sensor  4 , and the tensions of the guide ropes can be measured conveniently according to the reading on the pressure sensor  4 . 
     In  FIGS. 2-8 , the wedge-shaped rope ring  8  is depicted as hinged to the regulating plate  9  via a pin shaft, the hydraulic oil cylinder  10  is arranged in a notch of the regulating plate  9 , the upper part of the cylinder body  10 - 2  of the hydraulic oil cylinder  10  is connected with the bearing block  15  by bolts via the connecting holes  10 - 3  on the oil cylinder, and the bolts that connect the hydraulic oil cylinder  10  with the bearing block  15  also ensure tight conjugation between the two connecting plates. The piston rod  10 - 1  in the hydraulic oil cylinder  10  contacts with the cushion blocks  13  arranged on the bottom of the regulating plate  9 . The bearing blocks  15  and the pressing plates  16  are fixedly connected with the connecting plates  11  by bolts respectively. The protecting plates  14  are embedded in the notches  11 - 1  of the connecting plates and are fixed to the connecting plates  11  respectively, and the two protecting plates  14  are designed to fasten the cylinder body  10 - 2  of the oil cylinder. The two conjugated connecting plates  11  are connected to the flexible cable suspension platform  1  by a pin shaft via the connecting hole  11 - 2 . 
     As shown in  FIG. 9 , a two-position two-way directional control valve  22 , a non-return valve  19 , and a pressure sensor  4  are arranged sequentially between the oil outlet of the hydraulic pump  18  and the oil inlet of a hydraulic oil cylinder  10  respectively. To regulate the tensions of all the guide ropes  2  to the same value, all the two-position two-way directional control valves  22  should be set to the left position, while all the two-position three-way directional control valves  20  should be set to the right position, so that the oil chambers of all the hydraulic oil cylinders  10  communicate with each other and the pressure values in all the oil chambers are the same. Then, the system can regulate the tensions of the guide ropes  2  automatically to the same value. To regulate the tension of a specific guide rope  2 , the two-position two-way directional control valve  22  corresponding to the hydraulic oil cylinder  10  of the guide rope regulator connected with that guide rope  2  should be set to the right position, while the corresponding two-position three-way directional control valve  20  should be set to the left position, so that the oil outlet of the hydraulic oil cylinder  10  is connected with the pilot overflow valve  21 . Thus, the pressure in the oil chamber of the hydraulic oil cylinder  10  can be kept at a fixed value by regulating the pilot overflow valve  21  according to the reading on the pressure sensor  4  connected with the hydraulic oil cylinder  10 , and thereby the guide rope regulator  3  can regulate the tension of the guide rope, to keep the tension of the guide rope  2  at a fixed value.