Permanent magnet half-direct drive electric shovel hoisting mechanism and electric shovel

Abstract

The application discloses a permanent magnet half-direct drive electric shovel lifting mechanism, which comprises two parallel driving lifting motors, a lifting speed reducer, a lifting drum and an encoder, the lifting motor is a permanent magnet synchronous motor, the lifting speed reducer is a one-stage parallel shaft transmission speed reducer, the output shafts of the two lifting motors are respectively connected to an input shaft of the lifting speed reducer through couplings, a lifting brake is connected to the non-driving side of the lifting motor, the lifting drum is rotatably arranged between the lifting speed reducer box and a lifting side support through a lifting drum shaft, the output gear of the lifting speed reducer is connected to the lifting drum, the encoder is connected to the speed reducer side of the lifting drum shaft, and the sealing assembly of the lifting drum is arranged between the outer periphery of the lifting drum and the lifting speed reducer box. The application realizes the permanent magnet half-direct drive drum, has large output torque, can drive large load at low speed, guarantees the sealing effect of the lifting drum and the reliability of the encoder connection.

Description

Technical Field

[0001] This invention belongs to the field of electric shovel technology, and particularly relates to a permanent magnet semi-direct drive electric shovel lifting mechanism and an electric shovel including the permanent magnet semi-direct drive electric shovel lifting mechanism. Background Technology

[0002] Electric shovels are single-bucket excavators that use gears, chains, steel cables, pulley blocks, and other transmission components to transmit power. They are one of the main mining equipment in open-pit mines with a capacity of tens of millions of tons. They have high productivity, high operating rate, and low operating costs, and are recognized as a model in the mining industry. Electric shovels consist of a walking device, a slewing device, a working device, a lubrication system, an air supply system, and a lifting mechanism.

[0003] The lifting mechanism is one of the most important components of an electric shovel. The bucket relies on the lifting mechanism for raising and lowering, and is precisely controlled by a lifting encoder to prevent the lifting mechanism from operating beyond its limits. Due to the harsh working conditions of electric shovels, with large vibrations and impacts, especially the frequent forward and reverse rotation of the lifting mechanism, the efficient, reliable, and stable operation of the electric shovel depends primarily on the lifting mechanism.

[0004] Electric shovels require significant lifting torque during operation. When the lifting mechanism uses a DC motor or an AC variable frequency asynchronous motor, the motor's output torque is relatively small and cannot directly drive low-speed, high-load applications. At least two stages of transmission reduction are needed to meet the requirements. Later, this can lead to issues such as high-speed shaft bending, breakage, or seal problems, resulting in oil leakage from the seals and seepage from the lifting drum seals during operation. Furthermore, flexible shaft encoders have short lifespans, unreliable connections, and can trigger alarms when loosened.

[0005] Furthermore, existing lifting mechanism transmission systems suffer from low efficiency, high energy consumption, long transmission chains, and high maintenance costs. With the development of permanent magnet technology, the adoption of highly efficient, energy-saving, high-torque, and frequently starting permanent magnet synchronous motors as power sources will inevitably lead to more efficient, reliable, and stable operation of electric shovels. However, directly using a permanent magnet motor to drive the drum structure results in a large and expensive permanent magnet motor, difficult installation, and precise control under operating conditions where the shovel speed is below 20 rpm. Summary of the Invention

[0006] To address some or all of the technical problems existing in the prior art, the present invention provides a permanent magnet semi-direct drive electric shovel lifting mechanism, which is mounted on the rotating main platform of the electric shovel. The permanent magnet semi-direct drive electric shovel lifting mechanism includes two parallel-driven lifting motors, a lifting reducer, a lifting drum, and an encoder, wherein:

[0007] The two lifting motors are fixedly mounted on an integrated lifting motor base connected to the slewing main platform. The lifting motors are permanent magnet synchronous motors. The lifting reducer is a single-stage parallel shaft transmission reducer, which includes two parallel input shafts and a large output gear. The output shafts of the two lifting motors are respectively connected to one input shaft of the lifting reducer through a first coupling. A lifting brake is connected to the non-transmission side of each lifting motor.

[0008] The lifting drum is rotatably mounted between the lifting side support connected to the rotary main platform and the housing of the lifting reducer via a lifting drum shaft. One end of the lifting drum shaft is rotatably mounted on the housing of the lifting reducer, and the other end is rotatably mounted on the lifting side support. The output gear of the lifting reducer is connected to the lifting drum. The encoder is connected to the reducer side of the lifting drum shaft via a second coupling.

[0009] A drum sealing assembly is provided between the outer periphery of the lifting drum and the housing of the lifting reducer.

[0010] Furthermore, in the aforementioned permanent magnet semi-direct drive electric shovel lifting mechanism, the encoder is mounted on the bracket, the second coupling is mounted on the housing of the lifting reducer, and the second coupling connects the encoder and the reducer side of the lifting drum shaft, connecting the encoder's connecting pin to the lifting drum shaft.

[0011] Furthermore, in the aforementioned permanent magnet semi-direct drive electric shovel lifting mechanism, the drum sealing assembly includes a V-shaped sealing ring, a first J-shaped sealing ring, a second J-shaped sealing ring, a polyurethane spacer ring arranged between the first J-shaped sealing ring and the second J-shaped sealing ring, and an oil return port located at the lower part of the housing of the lifting reducer.

[0012] Furthermore, in the aforementioned permanent magnet semi-direct drive electric shovel lifting mechanism, the first J-type sealing ring and the second J-type sealing ring adopt a split sealing structure, wherein the first J-type sealing ring and the second J-type sealing ring are respectively formed by wrapping the sealing strip around the outer periphery of the lifting drum and then joining the two ends of the sealing strip with a 45° cut.

[0013] Furthermore, in the aforementioned permanent magnet semi-direct drive electric shovel lifting mechanism, the cut-off positions of the first J-type sealing ring and the second J-type sealing ring are offset relative to the central axis of the lifting drum.

[0014] Furthermore, in the aforementioned permanent magnet semi-direct drive electric shovel lifting mechanism, the housing of the lifting reducer is provided with a drum sealing assembly lubrication device for injecting oil into the drum sealing assembly.

[0015] Furthermore, in the aforementioned permanent magnet semi-direct drive electric shovel lifting mechanism, the first coupling is a drum-type gear coupling.

[0016] Furthermore, in the aforementioned permanent magnet semi-direct drive electric shovel lifting mechanism, the lifting brake is a hydraulic wet multi-disc brake.

[0017] On the other hand, the present invention also provides an electric shovel, which includes the above-mentioned permanent magnet semi-direct drive electric shovel lifting mechanism.

[0018] The permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention has the following advantages and beneficial effects:

[0019] Two parallel-drive permanent magnet synchronous motors are selected as the lifting motors, and a single-stage parallel shaft transmission reducer is selected as the lifting reducer. This enables the permanent magnet motor to drive the drum in a semi-direct manner, resulting in high output torque, which is capable of driving at low speeds and heavy loads. It is also highly efficient and energy-saving, with a short transmission chain, which reduces the space occupied by the electric shovel and lowers maintenance costs. It effectively avoids high-speed shaft bending deformation and shaft breakage, ensuring the electric shovel operates efficiently, reliably, and stably.

[0020] By setting a new structure of drum sealing assembly including one V-shaped sealing ring, two J-shaped sealing rings and a polyurethane spacer ring between the two J-shaped sealing rings, the sealing effect of the lifting drum is guaranteed and oil leakage of the lifting drum is effectively prevented.

[0021] By employing a coupling structure, the encoder is connected to the reducer side of the lifting drum shaft. The encoder is fixedly mounted on the bracket, and the coupling is fixedly mounted on the lifting reducer housing. The coupling connects the encoder's connecting pin to the lifting drum shaft, ensuring the reliability of the encoder connection and avoiding problems such as short service life and unreliable connection of existing flexible shaft encoders. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for further understanding of the embodiments of the present invention and constitute a part of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0023] Figure 1 This is a front view of the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention;

[0024] Figure 2 This is a top view of the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention;

[0025] Figure 3 It is along Figure 1Sectional view of AA;

[0026] Figure 4 It is along Figure 1 BB in the middle is a sectional view;

[0027] Figure 5 yes Figure 4 Enlarged diagram of section C;

[0028] Figure 6 This is a schematic diagram of the lifting drum sealing assembly in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention;

[0029] Figure 7 This is a schematic diagram of the misaligned J-type sealing ring of the lifting drum sealing assembly in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1-Lifting motor, 2-First coupling, 3-Lifting reducer, 31-Input shaft, 32-Output gear, 33-Box, 4-Lifting brake, 5-Lifting motor base, 6-Lifting drum, 7-Lifting drum shaft, 8-Lifting side support, 9-Lifting wire rope, 10-Encoder, 11-Drum sealing assembly, 111-V-ring seal, 112-First J-ring seal, 113-Second J-ring seal, 114-Polyurethane spacer, 115-Oil return port, 12-Drum sealing assembly lubrication device, 13-Second coupling, 100-Rotating main platform. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0033] like Figures 1 to 7As shown, the permanent magnet semi-direct drive electric shovel lifting mechanism provided by the present invention is mounted on the shovel's rotating main platform 100, including two parallel-drive lifting motors 1, a lifting reducer 3, a lifting drum 6, and an encoder 10. The two lifting motors 1 are fixedly mounted on an integrated lifting motor base 5, which is connected to the shovel's rotating main platform 100 via a stop and multiple super nuts. The lifting reducer 3 is a single-stage parallel shaft drive reducer, including two parallel input shafts 31 and a large output gear 32. The output shafts of the two lifting motors 1 are respectively connected to the lifting reducer via a first coupling 2. An input shaft 31 of the 3 is connected to a lifting brake 4 via a stop and bolts on the non-drive side of each lifting motor 1. The lifting drum 6 is rotatably mounted between the lifting side support 8 and the housing 33 of the lifting reducer 3 via the lifting drum shaft 7, which is connected to the rotating main platform 100 of the electric shovel via a stop and bolts. That is, one end of the lifting drum shaft 7 is rotatably mounted on the housing 33 of the lifting reducer 3, and the other end is rotatably mounted on the lifting side support 8. The output gear 32 of the lifting reducer 3 is connected to the lifting drum 6. The encoder 10 is connected to the reducer side of the lifting drum shaft 7 via a second coupling 13.

[0034] In the above-mentioned permanent magnet semi-direct drive electric shovel lifting mechanism, two parallel lifting motors 1 synchronously drive the lifting reducer 3. The output large gear 32 of the lifting reducer 3 drives the lifting drum shaft 7 to rotate under the synchronous drive of the two input shafts 31. As a result, the lifting drum 6 rotates, realizing the winding and unwinding of the lifting wire rope 9 wound on the lifting drum 6, thereby realizing the lifting and lowering of the electric shovel bucket. The bucket cooperates with the pushing mechanism to complete the loading and unloading of materials.

[0035] Furthermore, in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention, a drum sealing assembly 11 for effectively preventing oil leakage of the lifting drum 6 is provided between the outer periphery of the lifting drum 6 and the housing 33 of the lifting reducer 3. As a specific embodiment, such as... Figure 6 As shown, the drum sealing assembly 11 includes a V-shaped sealing ring 111, a first J-shaped sealing ring 112, a second J-shaped sealing ring 113, a polyurethane spacer 113 arranged between the first J-shaped sealing ring 112 and the second J-shaped sealing ring 113, and an oil return port 115 located at the lower part of the housing 33 of the lifting reducer 3.

[0036] Furthermore, in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention, a drum sealing assembly lubrication device 12 is provided on the housing 33 of the lifting reducer 3 for injecting oil into the drum sealing assembly 11 to ensure the drum sealing effect.

[0037] As one specific implementation method, such as Figure 7As shown, the first J-type sealing ring 112 and the second J-type sealing ring 113 of the drum sealing assembly 11 both adopt a split sealing structure. That is, the first J-type sealing ring 112 and the second J-type sealing ring 113 are respectively formed by wrapping a sealing strip around the outer circumference of the lifting drum 6 and then joining the two ends of the sealing strip with a 45° cut. Preferably, in order to further improve the oil leakage prevention effect of the lifting drum 6, the cut-joining position of the first J-type sealing ring 112 and the cut-joining position of the second J-type sealing ring 113 are offset relative to the central axis of the lifting drum 6.

[0038] For example, such as Figure 7 As shown in (a) and (b), the cut-off position of the first J-type sealing ring 112 is offset to the left by 25° relative to the central axis of the lifting drum 6, and the cut-off position of the second J-type sealing ring 113 is offset to the right by 25° relative to the central axis of the lifting drum 6. Thus, the cut-off positions of the first J-type sealing ring 112 and the second J-type sealing ring 113 are offset by 50° relative to the central axis of the lifting drum 6.

[0039] Furthermore, in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention, in order to ensure the reliability of the encoder 10 connection, such as... Figure 5 As shown, encoder 10 is mounted on a bracket, and second coupling 13 is mounted on housing 33 of lifting reducer 3. Second coupling 13 connects encoder 10 to the reducer side of lifting drum shaft 7, connecting the connecting pin of encoder 10 to lifting drum shaft 7. Thus, during the lifting drum shaft 7's rotation for raising and lowering the electric shovel bucket, encoder 10 detects the angular displacement data of lifting drum shaft 7 in real time and converts it into the required electrical pulse signal, assisting in the automatic control of the electric shovel operation. Simultaneously, since encoder 10 is fixedly mounted on the bracket and second coupling 13 is fixedly mounted on housing 33, the connection of encoder 10 is reliable, eliminating any risk of loosening.

[0040] In one specific implementation, in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention, the lifting motor 1 is a permanent magnet synchronous motor.

[0041] In one specific implementation, in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention, the first coupling 2 adopts a drum-type gear coupling.

[0042] In one specific embodiment, in the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention, the lifting brake 4 is a hydraulic wet multi-disc brake.

[0043] In summary, compared with the prior art, the permanent magnet semi-direct drive electric shovel lifting mechanism of the present invention has the following advantages and beneficial effects:

[0044] (1) This invention selects two parallel-drive permanent magnet synchronous motors as lifting motors and a single-stage parallel shaft transmission reducer as lifting reducer to realize semi-direct drive of the drum by permanent magnet motors. The output torque is large, which can handle low-speed and high-load drive. It is also highly efficient and energy-saving, with a short transmission chain, which reduces the space occupied by the electric shovel and has low maintenance costs. It effectively avoids the occurrence of high-speed shaft bending deformation and shaft breakage, and ensures that the electric shovel operates efficiently, reliably and stably.

[0045] (2) The present invention provides a novel structure of a drum sealing assembly, which includes a V-shaped sealing ring, two J-shaped sealing rings and a polyurethane spacer ring between the two J-shaped sealing rings, to ensure the sealing effect of the lifting drum and effectively prevent oil leakage from the lifting drum.

[0046] (3) The present invention uses a coupling structure to connect the encoder to the reducer side of the lifting drum shaft. The encoder is fixedly installed on the bracket and the coupling is fixedly installed on the lifting reducer housing. The coupling connects the encoder's connecting pin to the lifting drum shaft, ensuring the reliability of the encoder connection and avoiding the problems of short service life and unreliable connection of the soft shaft encoder in the prior art.

[0047] It should be noted that, unless otherwise expressly specified and limited, the term "connection" or its synonyms should be interpreted broadly in this document. For example, "connection" can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. Furthermore, expressions such as "first" and "second" are merely used to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Meanwhile, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. In addition, the terms "front," "rear," "left," "right," "upper," and "lower" in this document refer to the placement states shown in the accompanying drawings.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A permanent magnet half-direct drive electric shovel hoist mechanism provided on a slewing main platform of an electric shovel, characterized by, The permanent magnet half-direct drive electric shovel hoisting mechanism comprises two hoisting motors driven in parallel, a hoisting speed reducer, a hoisting drum and an encoder, wherein: The two hoisting motors are fixedly installed on an integrated hoisting motor base coupled to the slewing main platform, the hoisting motors are permanent magnet synchronous motors, the hoisting speed reducer is a one-stage parallel shaft transmission speed reducer comprising two parallel input shafts and an output bull gear, the output shafts of the two hoisting motors are respectively coupled to an input shaft of the hoisting speed reducer through a first coupling, and a hoisting brake is coupled to the non-driving side of each hoisting motor; The hoisting drum is rotatably installed between a hoisting side support coupled to the slewing main platform and the box of the hoisting speed reducer through a hoisting drum shaft, one end of the hoisting drum shaft is rotatably installed on the box of the hoisting speed reducer, the other end is rotatably installed on the hoisting side support, the output bull gear of the hoisting speed reducer is coupled to the hoisting drum, and the encoder is coupled to the speed reducer side of the hoisting drum shaft through a second coupling; A drum sealing assembly is arranged between the outer periphery of the hoisting drum and the box of the hoisting speed reducer, the drum sealing assembly comprises a V-shaped sealing ring, a first J-shaped sealing ring, a second J-shaped sealing ring, a polyurethane spacer ring arranged between the first J-shaped sealing ring and the second J-shaped sealing ring, and an oil return port arranged at the lower part of the box of the hoisting speed reducer; The first J-shaped sealing ring and the second J-shaped sealing ring adopt a split sealing structure, wherein the first J-shaped sealing ring and the second J-shaped sealing ring are respectively formed by winding a sealing strip around the outer periphery of the hoisting drum and then butt-jointing the two ends of the sealing strip at an angle of 45°; The butt-jointing positions of the first J-shaped sealing ring and the second J-shaped sealing ring are arranged in a staggered manner relative to the central axis of the hoisting drum.

2. The permanent magnet half-direct drive shovel hoist mechanism of claim 1, wherein, The encoder is installed on a bracket, the second coupling is installed on the box of the hoisting speed reducer, the second coupling is coupled between the encoder and the speed reducer side of the hoisting drum shaft, and the coupling pin shaft of the encoder is coupled to the hoisting drum shaft.

3. The permanent magnet half-direct drive shovel hoist mechanism of claim 1, wherein, The box of the hoisting speed reducer is provided with a drum sealing assembly lubricating device for lubricating the drum sealing assembly.

4. The permanent magnet half-direct drive shovel hoist mechanism of claim 1, wherein, The first coupling is a drum type tooth coupling.

5. The permanent magnet half-direct drive shovel hoist mechanism of claim 1, wherein, The hoisting brake is a hydraulic wet type multi-disc brake.

6. A dragline comprising: The electric shovel comprises the permanent magnet half-direct drive electric shovel hoisting mechanism according to any one of claims 1-5.

Images