Pulley block and balance arm device

Abstract

A pulley block and balance arm device relates to the technical field of cranes and comprises a duplex winding drum, a lifting hook and a balance mechanism, a balance mechanism is arranged on the other side of the top of the trolley; the balance mechanism comprises a support correspondingly connected with the trolley in a fastened mode, and a balance arm is hinged to the top of the support. Limiting columns for limiting the deflection angle of the balance arm are arranged at the two ends, corresponding to the balance arm, of the trolley, and limiting switches capable of being triggered by the balance arm are installed on column bodies of the limiting columns. Two steel wire ropes are respectively wound at two ends of the duplex winding drum, and are respectively and correspondingly fastened and connected with two ends of the balance arm through a tightness adjusting device after being wound with the movable pulley block; in the hoisting process, if one steel wire rope is accidentally broken, the other steel wire rope independently bears the hoisting weight, meanwhile, the balance arm triggers the limiting switch, the limiting switch sends out a stop signal, the duplex winding drum stops winding the steel wire ropes, the dangerous situation is prevented from occurring again, and the safety performance is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of cranes, in particular to a pulley block and a balancing arm device. Background Art

[0002] The lifting mechanism of a crane is usually equipped with a pulley block and a balance arm. The wire rope passes through the pulley block, the balance arm and the hook to complete the load lifting operation. This combined structure is widely used in the lifting mechanism of crane machinery. This structure can fully meet the use requirements for lifting ordinary equipment in the workshop. If some high-end equipment or some dangerous working environments require very stable lifting due to working conditions, it is also necessary to monitor whether the wire rope is likely to break to avoid major safety accidents.

[0003] A Chinese patent (publication number: CN203877775U) discloses a double-wire rope fault alarm crane trolley; the patent sets a balance support on the trolley frame, and the middle part of the balance beam is connected to the balance support through a balance spindle; a first pressure block and a first rope buckle are set at one end of the balance beam, and the first rope buckle is connected to the first wire rope, and a second pressure block and a second rope buckle are set at the other end, and the second rope buckle is connected to the second wire rope; a first limit seat and a first travel switch are set on the trolley frame below the first pressure block, and a second limit seat and a second travel switch are set on the trolley frame below the second pressure block, and the first travel switch and the second travel switch are simultaneously connected to the alarm controller signal; although the patent can send an alarm signal when any wire rope fails, it is difficult to level the balance beam during installation; in addition, the wire rope of the patent is easy to fall off from the fixed pulley during the lifting process. Utility Model Content

[0004] In order to overcome the deficiencies in the background technology, the utility model discloses a pulley block and a balancing arm device.

[0005] In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions:

[0006] A pulley block and a balancing arm device are installed on the trolley of a crane; the device comprises a double drum, a hook and a balancing mechanism; a double drum is installed on one side of the top of the trolley, and a balancing mechanism is provided on the other side; the balancing mechanism comprises a support which is fastened to a corresponding position of the trolley, and a balancing arm is hinged on the top of the support; both ends of the balancing arm corresponding to the trolley are provided with a limit column for limiting the deflection angle of the balancing arm, and the column body of the limit column is provided with a limit switch which can be triggered by the balancing arm; a hook is provided under the trolley, and the top of the hook is rotatably connected to a movable pulley block; a steel wire rope is wound around each end of the double drum, and after the two steel wire ropes are wound around the movable pulley block, they are fastened to the corresponding ends of the balancing arm through a tension adjustment device.

[0007] Preferably, the balancing mechanism further includes a bracket, with a balancing wheel group suspended on the top of the bracket through a hinged shaft; two fixed pulley groups are rotatably connected between the corresponding support of the trolley and the bracket; two movable pulley groups are rotatably connected to the top of the hook; the wire rope is wound several times between one of the movable pulley groups and a fixed pulley group, then redirected through the balancing wheel group, and after redirecting, it is wound several times between the other movable pulley group and the other fixed pulley group.

[0008] Preferably, the tension adjustment device includes a connecting rod and a connecting sleeve, one end of the connecting rod is hinged to the corresponding balance arm, and the other end is threadedly connected to the connecting sleeve. The end of the connecting sleeve facing away from the balance arm is rotatably connected to a connecting cap, and the connecting cap is tightly connected to the corresponding end of the wire rope.

[0009] Preferably, a top screw is installed on the end of the connecting sleeve away from the connecting cap.

[0010] Preferably, a hanging plate is provided between the tension adjusting device and the balancing arm, one end of the hanging plate is hinged to the balancing arm, and the other end is connected to the tension adjusting device.

[0011] Preferably, the tension adjustment device is hinged to the hanging plate via a pin-type sensor.

[0012] Due to the adoption of the above-mentioned technical solution, the utility model has the following beneficial effects:

[0013] The utility model discloses a pulley block and a balancing arm device with a simple structure, easy assembly and low production cost; limit columns for limiting the deflection angle of the balancing arm are provided at both ends of the trolley corresponding to the balancing arm, and the limit columns are installed with limit switches that can be triggered by the balancing arm; the balancing arm is in a balanced state during normal lifting; if one of the steel wire ropes breaks accidentally, the other steel wire rope bears the lifting weight alone, and at the same time the balancing arm deflects due to the unbalanced force, and the balancing arm collides with the corresponding limit column and continues to tighten the steel wire rope that bears the lifting weight to prevent the hook and the lifted object from falling; at the same time, the balancing arm triggers the limit switch, the limit switch sends a stop signal, and the double drum stops rewinding the steel wire rope to prevent the dangerous situation from occurring again, thereby effectively improving the safety performance.

[0014] The balancing mechanism of the present invention also includes a bracket, and a balancing wheel set is suspended on the top of the bracket through a hinge shaft. The rotation axis of the balancing wheel set is perpendicular to the hinge shaft, so that the balancing wheel set can automatically adapt to the direction of the wire rope, avoiding the phenomenon of the wire rope escaping from the wheel groove of the balancing wheel set.

[0015] The rope winding method of the utility model effectively increases the spacing between the steel ropes, improves the balance of the hook when it is raised and lowered, reduces the swing amplitude of the hook, and increases the safety of the lifting mechanism.

[0016] The utility model further provides a tension adjustment device between the wire rope and the hanging plate, one end of the tension adjustment device is tightly connected to the wire rope, and the other end is hinged to the hanging plate through a pin-type sensor; the pin-type sensor monitors the tension of the corresponding wire rope in real time. When the pin-type sensor on one side detects that the tension is 0, it is considered that the wire rope has broken and an alarm is started, thereby realizing the broken rope alarm function and further improving the safety performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the utility model;

[0018] Figure 2 It is a structural diagram of the balancing mechanism;

[0019] Figure 3 It is a side view of the balancing mechanism;

[0020] Figure 4 The following is a simplified diagram of the winding method of two steel wire ropes;

[0021] Figure 5 Schematic diagram of the structure of the tension adjustment device.

[0022] In the figure: 1. Trolley; 2. Double reel; 3. Hook; 4. Balancing mechanism; 4-1. Support; 4-2. Balancing arm; 4-3. Limit column; 4-4. Limit switch; 4-5. Balancing wheel assembly; 4-6. Fixed pulley assembly; 4-7. Hanging plate; 4-8. Pin-type sensor; 4-9. Bracket; 5. Movable pulley assembly; 6. Tension adjusting device; 6-1. Connecting rod; 6-2. Connecting sleeve; 6-3. Connecting cap; 6-4. Top screw. DETAILED DESCRIPTION

[0023] The present invention will be explained in detail through the following embodiments. The purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention. In the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "front", "back", "left", and "right" indicating directions or positional relationships, they are only corresponding to the drawings of the present application for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific direction.

[0024] Example 1, combined with the attached Figures 1 to 3 A pulley assembly and a balancing arm device are installed on a trolley 1 of a crane; they include a double drum 2, a hook 3 and a balancing mechanism 4; a double drum 2 is installed on one side of the top of the trolley 1, and a balancing mechanism 4 is provided on the other side; the balancing mechanism 4 includes a support 4-1 that is fastened to the corresponding trolley 1, and a balancing arm 4-2 is hinged on the top of the support 4-1; as shown in the attached figure Figure 4As shown, the middle part of the balancing arm 4-2 is hinged to the top of the support 4-1; both ends of the trolley 1 corresponding to the balancing arm 4-2 are provided with limit columns 4-3 for limiting the deflection angle of the balancing arm 4-2, and the limit column 4-3 is installed with a limit switch 4-4 that can be triggered by the balancing arm 4-2, that is, when the balancing arm 4-2 is unbalanced, it will deflect to one side until it collides with the corresponding limit column 4-3, and the limit switch 4-4 will be triggered at the same time.

[0025] A hook 3 is provided under the trolley 1, and the top of the hook 3 is rotatably connected to a movable pulley set 5; a steel wire rope is wound around each end of the double drum 2, and after the two steel wire ropes are wound around the movable pulley set 5, they are respectively fastened to the corresponding two ends of the balance arm 4-2 through the tension adjustment device 6, that is, the two steel wire ropes are independent of each other and bear equal weight. The distance between the corresponding end of the steel wire rope and the balance arm 4-2 is adjusted by the tension adjustment device 6, so that the operation of leveling the balance arm 4-2 can be facilitated.

[0026] During normal lifting, the balancing arm 4-2 is in a balanced state; if one of the steel wire ropes breaks accidentally, the other steel wire rope will bear the lifting weight alone, and the balancing arm 4-2 will deflect due to the imbalance of force. After the balancing arm 4-2 collides with the corresponding limit column 4-3, it will continue to tighten the steel wire rope that bears the lifting weight to prevent the hook 3 and the lifted object from falling; at the same time, the balancing arm 4-2 triggers the limit switch 4-4, and the limit switch 4-4 sends a stop signal, and the double drum 2 stops rewinding the steel wire rope to prevent dangerous situations from occurring again, thereby effectively improving safety performance.

[0027] It should be noted that in addition to the imbalance of the balance arm 4-2 caused by the breakage of the wire rope, the tangled rope phenomenon when the double drum 2 reels the wire rope will cause the two wire ropes to be unevenly stressed, which will also cause the imbalance of the balance arm 4-2 and trigger the limit switch 4-4 to remind the operator to deal with it in time, further improving the safety performance.

[0028] Example 2: To further enhance the stability during lifting, this example is further improved.

[0029] Combined with attachment Figures 1 to 4 , a pulley assembly and a balancing arm device, which is different from the embodiment 1 in that, on the basis of the embodiment 1, the balancing mechanism 4 further includes a bracket 4-9, and a balancing wheel assembly 4-5 is suspended on the top of the bracket 4-9 through a hinge shaft, as shown in the attached Figure 3 As shown, the rotation axis of the balancing wheel set 4-5 is perpendicular to the corresponding hinge axis, so that the balancing wheel set 4-5 can automatically adapt to the direction of the wire rope, avoiding the phenomenon that the wire rope escapes from the wheel groove of the balancing wheel set 4-5.

[0030] The trolley 1 is rotatably connected between the corresponding support 4-1 and the bracket 4-9 with two fixed pulley sets 4-6; the top of the hook 3 is rotatably connected with two movable pulley sets 5; the wire rope is wound several times between one movable pulley set 5 and a fixed pulley set 4-6, then redirected by the balance wheel set 4-5, and then wound several times between the other movable pulley set 5 and the other fixed pulley set 4-6;

[0031] As attached Figure 4 As shown, the steel wire rope wound around the left end of the double drum 2 is first wound several times between the movable pulley group 5 on the left and the fixed pulley group 4-6 on the left, and then changed direction through the balance wheel group 4-5. After changing direction, it is wound several times between the movable pulley group 5 on the right and the fixed pulley group 4-6 on the right, and then is fastened to the right end of the balance arm 4-2. The winding method of the steel wire rope wound around the right end of the double drum 2 is exactly opposite to the winding method of the steel wire rope wound around the left end.

[0032] It should be noted that if Figure 4 As shown, the steel wire rope wound around the left end of the double drum 2 is located on the inner side of the two movable pulley sets 5, and the steel wire rope wound around the right end of the double drum 2 is located on the outer side of the two movable pulley sets 5, which effectively widens the distance between the steel wire ropes, increases the balance of the hook 3 during lifting and lowering, reduces the swing amplitude of the hook, and increases the safety of the lifting mechanism.

[0033] Example 3: To further enhance safety performance, this example is further improved.

[0034] Combined with attachment Figure 2 and 5 , a pulley group and a balancing arm device, based on embodiment 1 or 2, the tension adjustment device 6 includes a connecting rod 6-1 and a connecting sleeve 6-2, one end of the connecting rod 6-1 is hinged to the corresponding balancing arm 4-2, and the other end is threadedly connected to the connecting sleeve 6-2, and the end of the connecting sleeve 6-2 away from the balancing arm 4-2 is rotatably connected to the connecting cap 6-3, and the connecting cap 6-3 is tightly connected to the corresponding end of the wire rope, that is, the distance between the corresponding end of the wire rope and the balancing arm 4-2 can be adjusted by screwing the connecting sleeve 6-2, so as to facilitate the operation of leveling the balancing arm 4-2; the end of the connecting sleeve 6-2 away from the connecting cap 6-3 is installed with a top screw 6-4, and when the balancing arm 4-2 is leveled, the top screw 6-4 can be tightened to prevent the connecting sleeve 6-2 and the connecting rod 6-1 from accidentally rotating relative to each other, causing the balancing arm 4-2 to become unbalanced.

[0035] A hanging plate 4-7 is provided between the tension adjustment device 6 and the balance arm 4-2. One end of the hanging plate 4-7 is hinged to the balance arm 4-2, and the other end is connected to the tension adjustment device 6. The tension adjustment device 6 is hinged to the hanging plate 4-7 through a pin-type sensor 4-8; the pin-type sensor 4-8 monitors the tension of the corresponding wire rope in real time. When the pin-type sensor on one side detects that the tension is 0, it is considered that the wire rope has broken, and an alarm is started, thereby realizing the broken rope alarm function; further improving the safety performance.

[0036] The parts of the present invention that are not described in detail are prior art. It is obvious to those skilled in the art that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and it is intended that all changes that fall within the meaning and scope of equivalent elements are included in the present invention.

Claims

1. A pulley assembly and a balancing arm device, mounted on a trolley (1) of a crane; characterized by: The invention comprises a double drum (2), a hook (3) and a balancing mechanism (4); a double drum (2) is installed on one side of the top of the trolley (1), and a balancing mechanism (4) is provided on the other side; the balancing mechanism (4) comprises a support (4-1) which is fixedly connected to the trolley (1), and a balancing arm (4-2) is hinged on the top of the support (4-1); a limit column (4-3) for limiting the deflection angle of the balancing arm (4-2) is provided at both ends of the trolley (1) corresponding to the balancing arm (4-2), and a limit switch (4-4) which can be triggered by the balancing arm (4-2) is installed on the column body of the limit column (4-3); a hook (3) is provided below the trolley (1), and a movable pulley group (5) is rotatably connected to the top of the hook (3); a steel wire rope is wound around each end of the double drum (2), and after the two steel wire ropes are wound around the movable pulley group (5), they are fixedly connected to the corresponding ends of the balancing arm (4-2) (6) through a tension adjustment device.

2. The pulley assembly and balance arm device according to claim 1, wherein: The balancing mechanism (4) further comprises a bracket (4-9), a balancing wheel group (4-5) being suspended on the top of the bracket (4-9) via a hinged shaft; the trolley (1) is rotatably connected to two fixed pulley groups (4-6) between the corresponding support (4-1) and the bracket (4-9); the top of the hook (3) is rotatably connected to two movable pulley groups (5); the wire rope is wound several times between one movable pulley group (5) and a fixed pulley group (4-6), and then redirected by the balancing wheel group (4-5), and then wound several times between another movable pulley group (5) and another fixed pulley group (4-6).

3. The pulley assembly and balance arm device according to claim 1, wherein: The tension adjustment device (6) comprises a connecting rod (6-1) and a connecting sleeve (6-2); one end of the connecting rod (6-1) is hinged to the balancing arm (4-2), and the other end is threadedly connected to the connecting sleeve (6-2); one end of the connecting sleeve (6-2) facing away from the balancing arm (4-2) is rotatably connected to a connecting cap (6-3); and the connecting cap (6-3) is tightly connected to the corresponding end of the wire rope.

4. The pulley assembly and balance arm device according to claim 3, wherein: A top screw (6-4) is installed on one end of the connecting sleeve (6-2) facing away from the connecting cap (6-3).

5. The pulley assembly and balance arm device according to claim 1, wherein: A hanging plate (4-7) is provided between the tension adjustment device (6) and the balance arm (4-2); one end of the hanging plate (4-7) is hinged to the balance arm (4-2), and the other end is connected to the tension adjustment device (6).

6. The pulley assembly and balance arm device according to claim 5, wherein: The tension adjustment device (6) is correspondingly hinged to the hanging plate (4-7) via a pin-type sensor (4-8).

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