Multi-row electric chain hoist

Abstract

The application discloses a multi-row type electric hoist with a chain, and positioning assemblies are arranged on the lifting chains on the two sides of the fixed pulley assembly at the middle position of the fixed plate respectively, the positioning assembly comprises a limiter assembly and a weight assembly, the weight assembly comprises a weight sleeve which is sleeved on the lifting chain and can move up and down freely relative to the lifting chain, the limiter assembly comprises a stop block assembly clamped on the lifting chain, a weight balance lever group which is rotatably connected to the stop block assembly, a weight limiting switch which is arranged below the weight balance lever group, and a steel wire rope which is connected between the weight balance lever group and the weight sleeve; and the heights of the two limiter assemblies and the two weight assemblies are different. By arranging the sensors with different triggering positions on the lifting chains on the two sides of the fixed pulley at the middle position respectively, multiple position signals can be collected, the lifting height of the electric hoist can be controlled according to actual needs, and various automatic operation requirements can be met.

Description

TECHNICAL FIELD

[0001] The present application relates to a multi-row endless chain electric hoist, belonging to the technical field of hoisting machinery. BACKGROUND

[0002] The endless chain electric hoist is widely used in various production workshops as a small hoisting equipment. The multi-row endless chain electric hoist usually adopts the structure of cooperating with the movable pulley and the fixed pulley to hoist the load by the left and right two electric hoists, which can realize the hoisting operation of larger tonnage.

[0003] With the continuous development of automation operation, the function of the traditional multi-row endless chain electric hoist in the hoisting height positioning aspect has been increasingly unable to meet the automation control demand. In the hoisting process of the product, it may be required to stay at different positions, or the height of the electric hoist required to stop is different for different hoisted products. The traditional multi-row endless chain electric hoist generally controls the start-stop position by artificial visual inspection, and it is basically unable to meet the hoisting operation of accurately controlling the stay height. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a multi-row endless chain electric hoist, which can collect multiple position signals by installing sensors with different trigger positions on the lifting chains on both sides of the fixed pulley at the middle position, so as to control the hoisting height of the electric hoist according to the actual needs, and meet the various automation operation requirements.

[0005] In order to solve the above technical problems, the technical scheme adopted by the present application is:

[0006] A multi-row endless chain electric hoist, comprising a fixed plate and a movable plate, the two ends of the fixed plate are respectively provided with electric hoists that can act synchronously, a single fixed pulley assembly is further arranged on the fixed plate, a double movable pulley assembly is arranged on the movable plate, a lifting hook assembly is arranged at the bottom of the movable plate, a lifting chain is connected between the two electric hoists, and the lifting chain sequentially passes through the movable pulley assembly and the fixed pulley assembly, a positioning assembly is arranged on the lifting chain on both sides of the fixed pulley assembly at the middle position of the fixed plate, the positioning assembly comprises a limit stop assembly and a weight assembly, wherein,

[0007] The weight assembly comprises a weight sleeve that can move up and down relative to the lifting chain freely;

[0008] The limit stop assembly comprises a stop block assembly clamped on the lifting chain, a weight balance rod group rotatably connected to the stop block assembly, a weight limit switch is arranged below the weight balance rod group, and a steel wire rope is connected between the weight balance rod group and the weight sleeve; and the heights of the two limit stop assemblies and the two weight assemblies are different.

[0009] The multi-row electric hoist of the chain type according to the preceding description, characterized in that: a limit position micro switch is arranged in the electric hoist, and a triggering spring for triggering the micro switch is sleeved on the outer end lifting chain of the movable pulley assembly 31 on both sides of the movable plate.

[0010] The multi-row electric hoist of the chain type according to the preceding description, characterized in that: the stop block assembly comprises a first chain stop block and a second chain stop block, opposite sides of the first chain stop block and the second chain stop block are provided with through grooves with the same shape along the length direction, the two through grooves are internally provided with protruding parts with the same height which can be clamped into the chain nest of the lifting chain, the first chain stop block and the second chain stop block are connected through an overload connecting rod assembly, the overload connecting rod assembly comprises a rod part and a head part, and a overload protection breaking groove is arranged at the connecting position between the rod part and the head part.

[0011] The multi-row electric hoist of the chain type according to the preceding description, characterized in that: threaded holes are arranged on the front and back sides of the first chain stop block, bolt holes corresponding to the number and position of the threaded holes are arranged on the second chain stop block, the rod part comprises a screw rod part which can be screwed into the threaded hole and a shoulder part, the overload protection breaking groove is arranged at the connecting position between the head part and the shoulder part, and the bolt hole comprises a first groove body with a gradually decreasing hole diameter for accommodating the head part, a second groove body for allowing the shoulder part to freely move, and a third groove body for allowing only the screw rod part to freely pass through.

[0012] The multi-row electric hoist of the chain type according to the preceding description, characterized in that: the protruding part is an arc structure, and the arc degree is consistent with the arc degree of the surface of the lifting chain.

[0013] The multi-row electric hoist of the chain type according to the preceding description, characterized in that: a limit push plate is arranged at the bottom of the stop block assembly, the limit push plate is connected to the stop block assembly through four connecting rods, a compression spring is sleeved on each of the connecting rods, a push plate limit switch which can be triggered by the upward movement of the limit push plate is arranged on the side surface of the stop block assembly, and a buffer spring is sleeved on the lifting chain.

[0014] The multi-row electric hoist of the chain type according to the preceding description, characterized in that: the cross section of the weight balance lever group is a C-shaped structure, the front and back side surfaces are rotatably connected to the second chain stop block through a fixed pin shaft, the end surface of the weight balance lever group is located on the outer side surface of the second chain stop block, the weight limit switch is located below the end surface of the weight balance lever group, and a torsional spring is arranged on the fixed pin shaft.

[0015] The multi-row electric hoist of the chain type according to the preceding description, characterized in that: the end of the front and back side surfaces of the weight balance lever group is an inwardly bent arc structure.

[0016] The beneficial effects of the present application are:

[0017] 1. By installing sensors with different trigger positions on the hoisting chains on both sides of the fixed pulley in the middle position, multiple position signals can be collected, which facilitates the control of the lifting height of the electric hoist according to actual needs to meet various automation operation requirements. Specifically, a heavy hammer sleeve and a heavy hammer balance bar group are used to form a heavy hammer type limit as the first section limit, and the limit position can be adjusted by changing the length of the steel wire rope connecting the two according to needs; a push plate type limit is used as the second section limit, and four position signals can be combined into different protection modes according to needs;

[0018] 2. By setting the limiter into a separable structure, under normal circumstances, the movable plate will trigger the micro switch in the electric hoist through the trigger spring, so as to trigger the motor to stop rotating. Once the micro switch fails, the separable limiter can ensure that when the movable plate reaches the set limit position, the limiter can be separated to release the limit of the chain, so that the chain can continue to move to compensate for the tension caused by inertia when the motor suddenly stops, while ensuring safety when limiting the limit of the lifting hook;

[0019] 3. By setting an overload protection breaking groove on the bolt assembly for connecting the two stop blocks, when the tension on the chain is too large, the bolt assembly can be separated at the overload protection breaking groove, so that the two stop blocks are separated, releasing the limit of the chain. At the same time, through the special design of the bolt hole and the setting of the heavy hammer balance bar group on the second stop block, after the bolt assembly breaks at the overload protection breaking groove, it can not only meet the separation of the two stop blocks, so that the hoisting chain can pass smoothly, but also can ensure that the separated bolt assembly will not fall from the hoisting chain, avoiding the situation of high-altitude falling objects. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a structural schematic view of a multi-row type ring chain electric hoist of the present application;

[0021] Figure 2 is a structural schematic view of a limiter and a heavy hammer group of a multi-row type ring chain electric hoist of the present application connected to the hoisting chain;

[0022] Figure 3 is a top view of a limiter of a multi-row type ring chain electric hoist of the present application;

[0023] Figure 4 is a split schematic view of a first chain stop block and a second chain stop block of a limiter of a multi-row type ring chain electric hoist of the present application;

[0024] Figure 5 is a structural schematic view of an overload connecting link assembly of a limiter of a multi-row type ring chain electric hoist of the present application;

[0025] Figure 6 This is a top view of the counterweight balance bar assembly of a multi-row electric chain hoist according to the present invention.

[0026] Figure 7 This is a side view of the counterweight balance bar assembly of a multi-row electric chain hoist according to the present invention. Detailed Implementation

[0027] The present invention will now be further described with reference to the accompanying drawings.

[0028] like Figures 1-7 As shown, a multi-row electric chain hoist includes a fixed plate 10 and a movable plate 30. Electric hoists 20 that can operate synchronously are respectively provided at both ends of the fixed plate 10. An odd number of fixed pulley assemblies 11 are also provided on the fixed plate 10, and an even number of movable pulley assemblies 31 are provided on the movable plate 30. A hook assembly 40 is provided at the bottom of the movable plate 30. A chain 50 connecting the two electric hoists 20, consisting of the movable pulley assembly 31 and the fixed pulley assembly 11, is provided between them. Positioning devices are respectively provided on the chains 50 on both sides of the fixed pulley assembly 11 at the middle position of the fixed plate 10. The positioning component includes a limiter assembly 70 and a counterweight assembly 60. The counterweight assembly 60 includes a counterweight sleeve 61 that is fitted onto the suspension chain 50 and can move freely up and down relative to it. The limiter assembly 70 includes a stop block assembly that is snapped onto the suspension chain and a counterweight balance bar assembly 74 that is rotatably connected to the stop block assembly. A counterweight limit switch 75 is provided below the counterweight balance bar assembly 74. A steel wire rope 63 connects the counterweight balance bar assembly 74 and the counterweight sleeve 61. The two limiter assemblies 70 and the two counterweight assemblies 60 have different heights.

[0029] By setting an odd number of fixed pulley assemblies 11 on the fixed plate and an even number of movable pulley assemblies 31 on the movable plate 30, it can be ensured that the position of the hanging chain on the upper part of both sides of the fixed pulley assembly 11 in the middle position will not change with the electric hoist's raising and lowering of the hanging chain. Therefore, the positioning components installed on the hanging chains on both sides of the fixed pulley assembly 11 will not change their relative positions before being triggered.

[0030] According to the requirements of different trigger positions, the two limit switch assemblies 70 are fixed at two suitable positions with different heights of the chain 50. Then, according to the requirements of the hammer-type limit trigger, a steel wire rope 63 of appropriate length is selected, and two hammer sleeves 61 are respectively fitted on the chain 50 at the two corresponding different height positions. The hammer sleeves 61 are used to pull the corresponding hammer balance bar assembly 74 to make it leave the hammer limit switch 75.

[0031] When the two sides of the electric hoist 20 are synchronously winding the chain 50, the movable plate 30 gradually rises until it contacts the lower weight sleeve 61, the pulling force of the corresponding weight balance lever set 74 disappears, and the stop block assembly of the relative limiter assembly 70 rotates and triggers the weight limit switch 75, generating the first positioning trigger signal. At this point, the electric hoist can stop according to needs, or continue to lift the movable plate according to needs until the second weight sleeve 61 is triggered, triggering the corresponding weight limit switch 75 in the same way to generate the second positioning trigger signal. At this point, the electric hoist can make the preset action, such as stopping lifting, lowering, or continuing to lift.

[0032] The bottom of the stop block assembly is provided with a limit push plate 77, which is connected to the stop block assembly by four connecting rods 78, and a compression spring is sleeved on each connecting rod 78. The side of the stop block assembly is provided with a push plate limit switch 76 that can be triggered by the upward movement of the limit push plate 77. The weight sleeve 61 is also provided with a buffer spring 62 sleeved on the chain 50.

[0033] When the electric hoist receives the two positioning signals triggered by the weight limit switch 75, and continues to lift the movable plate, it will trigger two push plate limit switches 76 in turn, thereby generating the third and fourth positioning signals. By collecting four different position signals, the lifting height of the electric hoist can be controlled according to actual needs to meet various automation operation requirements, or different protection modes can be combined.

[0034] The electric hoist 20 is provided with a limit position micro switch, and the outer side end chain 50 of the movable pulley assembly 31 on both sides of the movable plate 30 is sleeved with a trigger spring 51 for triggering the micro switch. If the electric hoist continues to lift the positioning plate after triggering the above four position signals, the micro switch in the electric hoist will be triggered by the trigger spring 51, indicating that it has reached the limit position and needs to control the electric hoist to stop lifting.

[0035] The stop block assembly includes a first chain stop block 71 and a second chain stop block 72. The opposite sides of the first chain stop block 71 and the second chain stop block 72 are provided with a through slot along the length direction, and the inner sides of the two through slots are provided with a protruding part 711 with the same height which can be clamped into the chain nest of the chain 50. The first chain stop block 71 and the second chain stop block 72 are connected by an overload connecting rod assembly 73. The overload connecting rod assembly 73 includes a rod part and a head part 733, and a overload protection fracture groove 734 is arranged at the connection between the rod part and the head part.

[0036] If the electric hoist does not stop after the micro switch is triggered, or the micro switch is not triggered in case of failure, the lower stop block assembly will generate a momentary resistance to the lifting chain 50, causing the motor to exceed the load and stop rotating. However, the motor still has a certain rotational inertia to continue pulling the lifting chain, thereby generating an outward extrusion force on the protrusions 711 of the two chain stop blocks, causing the overload link assembly 73 to break at the overload protection breaking groove 734, and the limiter to release the lifting chain, allowing the lifting chain to move upward for a distance until the pulling force generated by the motor's rotational inertia is compensated, and the risk of high-altitude falling objects caused by the motor's rotational inertia pulling the lifting chain is eliminated.

[0037] The first chain stop block 71 is provided with threaded holes 712 on both sides, and the second chain stop block 72 is provided with bolt holes 721 corresponding in number and position to the threaded holes 712. The rod part includes a screw rod part 731 that can be screwed into the threaded holes 712 and a shoulder part 732. The overload protection breaking groove 734 is arranged at the connection between the head part 733 and the shoulder part 732, and the bolt holes 721 include a first groove body 722 for accommodating the head part 733, a second groove body 723 for allowing the shoulder part 732 to move freely, and a third groove body 724 for allowing only the screw rod part 731 to pass freely.

[0038] When the overload link assembly 73 breaks at the overload protection breaking groove 734, the first chain stop block 71 moves outward with the screw rod part 731 and the shoulder part 732 relative to the second chain stop block 72. At this time, the shoulder part 732 is blocked and limited in the second groove body 723 at the third groove body 724. The length of the second groove body 723 is the length of the separation between the first chain stop block 71 and the second chain stop block 72, which can ensure that the chain can pass between them and that the first chain stop block 71 and the second chain stop block 72 can still be fitted on the chain without falling off.

[0039] The protrusions 711 are arc-shaped structures with an arc that is consistent with the arc of the surface of the lifting chain 50. This can ensure that the first chain stop block 71 and the second chain stop block 72 are completely locked on the lifting chain after being locked by the overload link assembly 73, and can better accommodate the chain thrust at the limit position, allowing the lifting chain assembly to apply a smaller thrust to break the overload link assembly 73 at the overload protection breaking groove 734, ensuring that the force required to break the breaking groove 734 is much smaller than the force required to break the lifting chain assembly.

[0040] The cross section of the heavy hammer balance bar group 74 is a C-shaped structure, the front and back two sides are rotatably connected to the second chain stop block 72 through a fixed pin shaft 79, the end face of the heavy hammer balance bar group 74 is located on the outer side of the second chain stop block 72, the heavy hammer limiting switch 75 is located below the end face of the heavy hammer balance bar group 74, and the fixed pin shaft 79 is provided with a torsional spring 80. The end face of the heavy hammer balance bar group 74 at the outer side of the second chain stop block 72 is used to block the separated head 733, so that the high-altitude falling situation is prevented. Therefore, even if the limiting device is broken due to overload, any part will not fall, and the high-altitude falling situation is avoided. The fixed pin shaft 79 is provided with a torsional spring 80, so as to ensure the stability of the heavy hammer balance bar group 74, and the sudden impact in the chain movement process is eliminated, and the heavy hammer limiting is not too sensitive and abnormally operated.

[0041] The end of the front and back two sides of the heavy hammer balance bar group 74 is an inwardly bent arc-shaped structure. The heavy hammer balance bar group 74 can be stably fixed outside the stop block assembly, a protection buckle for preventing excessive inclination is formed, the inclination angle of the heavy hammer balance bar group 74 is limited, and the phenomenon that the protection operation is lost due to the too large inclination angle is avoided.

[0042] In summary, the multi-row type ring chain electric hoist provided by the application can collect multiple position signals by installing sensors with different trigger positions on both sides of the intermediate position pulley, facilitate control of the lifting height of the electric hoist according to actual needs, meet various automatic operation needs, and further set two limit position protection mechanisms with different forms.

[0043] The basic principles, main features and advantages of the application are shown and described above. It should be understood by those skilled in the art that the application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the application. Without departing from the spirit and scope of the application, various changes and improvements can be made to the application, and these changes and improvements all fall within the scope of the claimed application. The scope of protection of the application is defined by the appended claims and their equivalents.

Claims

1. A multi-row electric hoist with endless chain, comprising a fixed plate (10) and a movable plate (30), two ends of the fixed plate (10) are respectively provided with electric hoists (20) capable of synchronous action, and a single number of fixed pulley assemblies (11) are further provided on the fixed plate (10), a double number of movable pulley assemblies (31) are provided on the movable plate (30), and a lifting hook assembly (40) is provided at the bottom of the movable plate (30), a lifting chain (50) connected with the movable pulley assemblies (31) and the fixed pulley assemblies (11) in sequence is connected between the two electric hoists (20), characterized in that: Positioning assemblies are arranged on both sides of the hoisting chains (50) at both sides of the fixed pulley assembly (11) in the middle of the fixed plate (10), the positioning assemblies comprise a limiter assembly (70) and a weight assembly (60), wherein, The weight assembly (60) comprises a weight sleeve (61) which is sleeved on the hoisting chain (50) and can freely move up and down relative to the hoisting chain (50); The limiter assembly (70) comprises a stop block assembly which is clamped on the hoisting chain, a weight balance lever group (74) which is rotatably connected to the stop block assembly, a weight limiting switch (75) which is arranged below the weight balance lever group (74), and a steel wire rope (63) which is connected between the weight balance lever group (74) and the weight sleeve (61); the two limiter assemblies (70) are different in height, and the two weight assemblies (60) are different in height; The stop block assembly comprises a first chain stop block (71) and a second chain stop block (72), opposite sides of the first chain stop block (71) and the second chain stop block (72) are provided with through grooves which are consistent in shape along the length direction, the through grooves are internally provided with protruding portions (711) which are consistent in height and can be clamped into chain pockets of the hoisting chain (50), the first chain stop block (71) and the second chain stop block (72) are connected through an overload connecting rod assembly (73), the overload connecting rod assembly (73) comprises a rod portion and a head portion (733), and an overload protection breaking groove (734) is arranged at the connection between the rod portion and the head portion.

2. A multi-row electric chain hoist according to claim 1, characterized in that: A limit position micro switch is arranged in the electric hoist (20), and a trigger spring (51) for triggering the micro switch is sleeved on the outer side end hoisting chain (50) of the movable pulley assembly (31) at both sides of the movable plate (30).

3. A multi-row electric chain hoist according to claim 2, characterized in that: Threaded holes (712) are arranged on both sides of the first chain stop block (71), bolt holes (721) corresponding in number and position to the threaded holes (712) are arranged on the second chain stop block (72), the rod portion comprises a screw rod portion (731) which can be screwed into the threaded holes (712) and a shoulder portion (732), the overload protection breaking groove (734) is arranged at the connection between the head portion (733) and the shoulder portion (732), and the bolt holes (721) comprise a first groove body (722) for accommodating the head portion (733) which is gradually smaller in hole diameter, a second groove body (723) through which the shoulder portion (732) can freely move, and a third groove body (724) through which only the screw rod portion (731) can freely pass.

4. A multi-row electric chain hoist according to claim 3, characterized in that: The protruding portion (711) is of an arc structure, and the curvature thereof is consistent with the curvature of the surface of the hoisting chain (50).

5. A multi-row electric chain hoist according to claim 4, characterized in that: The bottom of the stopper assembly is provided with a limit push plate (77), the limit push plate (77) is connected on the stopper assembly through four connecting rods (78), and the connecting rods (78) are all sleeved with compression springs; the side surface of the stopper assembly is provided with a push plate limit switch (76) which can be triggered by moving upward on the limit push plate (77); the weight sleeve (61) is further provided with a buffer spring (62) sleeved on the hanging chain (50).

6. A multi-row electric chain hoist according to claim 5, characterized in that: The cross section of the weight balance lever group (74) is a C-shaped structure, the front and rear side surfaces thereof are rotatably connected on the second chain stopper (72) through fixed pin shafts (79), the end surface of the weight balance lever group (74) is located on the outer side surface of the second chain stopper (72), the weight limit switch (75) is located below the end surface of the weight balance lever group (74), and the fixed pin shafts (79) are provided with torsional springs (80).

7. A multi-row electric chain hoist according to claim 6, characterized in that: The terminal ends of the front and rear side surfaces of the weight balance lever group (74) are inwardly bent arc-shaped structures.

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