Low-body coal mining machine rocker arm structure with wide mining range

Abstract

The present application relates to a kind of short body coal cutter rocker arm structure with wide exploitation range, the free end of the left and right extension section of the L-shaped transmission box of arm support shell and the free end of front and rear extension section are respectively provided with transmission input interface structure and transmission output interface structure, the left and right extension section of transmission box is also respectively provided with left and right extension front and rear support arm, front and rear support arm are all cantilever structure with one end being connected on transmission box, front and rear support arm are respectively provided with front and rear hinged interface structure, the hinged axis of front hinged interface structure, the hinged axis of rear hinged interface structure and the rotation axis of transmission input interface structure coincide, and the rotation axis of transmission output interface structure is also along front and rear direction extension.The present application is more reliable with the connection of fixed reduction box, exploitation lower limit is lower, exploitation upper limit is higher, and is suitable for the exploitation of thin or extremely thin coal seam.

Description

Technical Field

[0001] This invention relates to a rocker arm for a coal mining machine, which is particularly suitable for low-profile coal mining machines. After application, it can increase the mining range of the corresponding coal mining machine and adapt to the mining of thin and extremely thin coal seams in coal and rock working faces with more complex geological conditions. Background Technology

[0002] Early hydraulic coal mining machines (such as the MG300-W) used a matching structure of a fixed gearbox with cutting power and a rocker arm without cutting power to achieve complete cutting function. Its advantage was that the large power component did not need to swing with the rocker arm. This type of coal mining machine could adapt to mining coal seams with relatively thin lower limits. However, the root connecting cylinder of the rocker arm in this structure usually experienced high stress, making it prone to breakage. Furthermore, this structure generally used a long hydraulic cylinder support arm, making it unsuitable for mining below the thin coal seam depth. This structure is now largely obsolete.

[0003] In the existing improved connection structure that can adapt to thin coal seams, the drum's stress point is on one side of the boom support stress point, forming a cantilever structure. The large stress at the drum will affect the connection reliability of the boom support stress point. Summary of the Invention

[0004] The present invention aims to provide a rocker arm structure for a low-profile coal mining machine with a wide mining range. Its connection with the fixed gearbox is more reliable, the lower limit of mining is lower, the upper limit of mining is higher, and it is suitable for mining thin or extremely thin coal seams.

[0005] The main technical solutions of this invention are as follows:

[0006] A boom structure for a low-profile coal mining machine with a wide mining range includes a boom housing. The boom housing includes an L-shaped transmission box. The free ends of the left and right extensions of the transmission box are provided with transmission input interface structures, and the front ends of the front and rear extensions of the transmission box are provided with transmission output interface structures. A front support arm and a rear support arm are respectively provided at the front and rear of the left and right extensions of the transmission box. Both the front and rear support arms are cantilever structures with one end connected to the transmission box. The top surfaces of the front and rear support arms are not higher than the top surface of the transmission box, and the bottom surfaces of the front and rear support arms are not lower than the bottom surface of the transmission box. The front and rear support arms are respectively provided with a front hinge interface structure and a rear hinge interface structure. The hinge axis of the front hinge interface structure, the hinge axis of the rear hinge interface structure, and the rotation axis of the transmission input interface structure coincide, and like the rotation axis of the transmission output interface structure, they all extend in the front-rear direction.

[0007] The transmission housing is equipped with a rear-stage cutting transmission mechanism, which may include a rear-stage first gear, a rear-stage idler gear, and a rear-stage gear shaft arranged in sequence and meshing with each other. The core of the rear-stage first gear is provided with a spline hole, the opening of which is located on the front end face of the rear-stage first gear. The center line of the spline hole coincides with the center line of the rear-stage first gear, and the center line of the spline hole is the rotation axis of the transmission input interface structure.

[0008] The front support arm and the rear support arm are respectively provided with a front through hole and a rear through hole. The front through hole and the rear through hole are coaxial. The front transition sleeve and the rear transition sleeve are respectively coaxially fixedly installed in the front through hole and the rear through hole. The front transition sleeve and the front through hole form a front hinge interface structure, and the rear transition sleeve and the rear through hole form a rear hinge interface structure.

[0009] The front support arm and the rear support arm may also be equipped with a front automatic lubrication device and a rear automatic lubrication device, respectively, with the lubrication points of the front automatic lubrication device and the rear automatic lubrication device located on the inner hole surface of the front transition sleeve and the rear transition sleeve, respectively.

[0010] Preferably, the free end of the front support arm is also provided with a hydraulic cylinder connecting lug.

[0011] The front support arm can be L-shaped. The free ends of the left and right extensions of the front support arm are the free ends of the front support arm. The rear ends of the front and rear extensions of the front support arm are connected to the transmission housing. The top surface of the front and rear extensions of the front support arm is an inclined surface, and the height decreases as it moves away from the free end of the front support arm.

[0012] The top and bottom surfaces of the free end of the front support arm are preferably configured as outer cylindrical surfaces coaxial with the hinge axis of the front hinge interface structure.

[0013] The beneficial effects of this invention are:

[0014] Because multiple support connection points are set between the boom housing and the housing of the fixed gearbox, and these support connection points are respectively arranged in front of and behind the power transmission connection point, the radial displacement caused by wear at the two support connection points has less impact on the power transmission connection point located between them. Therefore, this support connection structure can provide a more reliable guarantee for the transmission of cutting power.

[0015] By adding front and rear automatic lubrication devices at the front and rear support connection points, automatic, effective, and long-term lubrication of the support bearing surfaces can be ensured, reducing wear and extending the service life of the support connection points.

[0016] By providing a cylinder connecting lug on the outside of the free end of the front support arm, the lever arm for the height adjustment cylinder to drive the rocker arm to swing is shortened. Therefore, with the same stroke of the height adjustment cylinder, the rocker arm structure of the present invention can achieve a larger rocker arm swing angle and swing angle range, and a wider height range.

[0017] The thickness of both the front and rear support arms is smaller than that of the transmission housing and much smaller than the diameter of the matching drum. This minimizes interference between the front and rear support arms and the top coal platform when the boom housing is at its limit position, allowing for higher mining heights. For mining extremely thin or thin coal seams, the rocker arm structure of this invention achieves both a lower lower mining limit and a higher upper mining limit, thus creating a wider mining range and making it suitable for low-profile coal mining machines.

[0018] Furthermore, the top surface of the front and rear extension sections of the front support arm is set as an inclined plane with a set angle and a specific highest point position. The inclination direction of the inclined plane is such that the height decreases the further away from the free end of the front support arm. This ensures that when the boom housing is at the limit position of the upper cutting tool, the entire front support arm is below the top surface of the housing of the fixed gearbox, thus preventing interference between the front support arm and the coal platform.

[0019] The connection between the free end of the front support arm and the housing of the fixed gearbox is designed with a partial cylindrical surface clearance fit structure, which can effectively prevent dust and other impurities from entering the housing of the fixed gearbox from the free end of the front support arm, thus helping to ensure the cleanliness of the inner cavity of the fixed gearbox. Attached Figure Description

[0020] Figure 1 This is a front view of an embodiment of the present invention;

[0021] Figure 2 This is a top sectional view of an embodiment of the present invention;

[0022] Figure 3 for Figure 2 AA section view;

[0023] Figure 4 This is a schematic diagram showing the clearance fit between the free end of the front support arm and the housing of the fixed gearbox;

[0024] Figure 5 This is a schematic diagram of the state of a low-profile coal mining machine using the rocker arm structure of the present invention when the rear rocker arm is at the limit position of the upper cutting tool.

[0025] Figure label:

[0026] 1. Boom housing; 11. Transmission housing; 12. Front support arm; 121. Outer cylindrical surface; 122. Outer cylindrical surface; 123. Inclined surface; 124. Cylinder connecting lug; 13. Rear support arm; 141. Front transition sleeve; 142. Rear transition sleeve; 151. Front automatic lubrication device; 152. Rear automatic lubrication device;

[0027] 21. Rear stage first gear; 211. Splined bore; 22. Rear stage idler gear; 23. Rear stage gear shaft;

[0028] 3. Roller;

[0029] 41. Housing of fixed gearbox; 411. Inner cylindrical surface; 412. Inner cylindrical surface. Detailed Implementation

[0030] This invention discloses a rocker arm structure (which may be simply referred to as a rocker arm structure) for a low-profile coal mining machine with a wide mining range, such as... Figure 1-5 As shown, it includes a boom housing 1, which includes an L-shaped transmission housing 11, and the free ends of the left and right extensions of the transmission housing (corresponding to...) Figure 2 The right end of the transmission housing 11 is provided with a transmission input interface structure, and the front end of the front and rear extensions of the transmission housing (i.e., the end near the coal wall) is provided with a transmission output interface structure. The transmission input interface structure and the transmission output interface structure are used to connect with the front-stage cutting transmission mechanism and the drum, respectively. A front support arm 12 and a rear support arm 13 are respectively provided at the front and rear of the left and right extensions of the transmission housing. Both the front and rear support arms are cantilever structures with one end connected to the transmission housing. In the left-right direction, the free ends of the front and rear support arms are located on the same side as the free end of the transmission housing. The extension direction of the local structures on the front and rear support arms near their respective free ends is parallel to the left and right extensions of the transmission housing. The top surfaces of the front and rear support arms are not higher than the top surface of the transmission housing, and the bottom surfaces of the front and rear support arms are not lower than the bottom surface of the transmission housing. The front support arm and the rear support arm are respectively provided with a front hinge interface structure and a rear hinge interface structure. The hinge axis of the front hinge interface structure, the hinge axis of the rear hinge interface structure, and the rotation axis of the transmission input interface structure coincide, and like the rotation axis of the transmission output interface structure, they all extend in the front-to-back direction. In this embodiment, the front support arm, the rear support arm, and the transmission housing are an integral structure.

[0031] The rocker arm structure is hinged to the housing 41 of the fixed gearbox of the coal mining machine via the front and rear hinge interfaces. The front-stage cutting transmission mechanism in the fixed gearbox transmits power to the rocker arm structure through the transmission input interface. Since the support connection points formed between the boom housing and the fixed gearbox housing are located in front of and behind the power transmission connection point, respectively, radial displacement caused by wear at the two support connection points has less impact on the power transmission connection point located between them. Therefore, this support connection structure provides a more reliable guarantee for the transmission of cutting power. Furthermore, the average stress point of the drum is located between the two support connection points, resulting in a better stress state for the boom housing.

[0032] The top surfaces of both the front and rear support arms are not higher than the top surface of the transmission housing, and the bottom surfaces of both the front and rear support arms are not lower than the bottom surface of the transmission housing. This means the upper and lower thicknesses of the front and rear support arms are both less than that of the transmission housing. This minimizes interference between the front and rear support arms and the top coal platform when the boom housing is at its limit position, allowing for higher mining heights. For mining extremely thin or thin coal seams, the rocker arm structure of this invention achieves both a lower lower mining limit and a higher upper mining limit, thus creating a wider mining range and making it suitable for low-profile coal mining machines.

[0033] The transmission housing houses a rear-stage cutting transmission mechanism for transmitting power from the front-stage cutting transmission mechanism to the drum. The rear-stage cutting transmission mechanism includes a rear-stage first gear 21, a rear-stage idler gear 22, and a rear-stage gear shaft 23 arranged sequentially and meshing with each other. The rear-stage first gear and the rear-stage gear shaft are rotatably supported on the transmission housing by bearings. The rear-stage idler gear is rotatably supported on the rear-stage idler gear shaft by bearings, and the rear-stage idler gear shaft is fixedly mounted on the transmission housing. The core of the rear-stage first gear has a spline hole 211, the opening of which is located on the front end face of the rear-stage first gear. The centerline of the spline hole coincides with the centerline of the rear-stage first gear, and the centerline of the spline hole is the rotation axis of the transmission input interface structure. The spline hole is the core of the transmission input interface structure. The rear-stage gear shaft is the core of the transmission output interface structure; for example, the front part of the rear-stage gear shaft can be configured as a splined shaft section for connecting to the drum.

[0034] The rear idler gears can be one or multiple gears meshing sequentially. When the number of rear idler gears is different, the length of the boom housing is different, and correspondingly, the length of the rocker arm structure is also different; the more rear idler gears, the longer the boom housing. When the rocker arm structure is installed with the same front-stage cutting transmission mechanism, under the condition that the cutting motor rotates in the same direction, the rotation of the drums obtained by odd and even numbers of rear idler gears are opposite. Therefore, when the two sets of front-stage cutting transmission mechanisms on the left and right sides of a double-drum coal mining machine are symmetrically arranged and driven by one cutting motor, the rocker arm structures with odd and even numbers of rear idler gears on the left and right sides can achieve different output rotations of the left and right drums.

[0035] The front and rear support arms are respectively provided with a front through hole and a rear through hole, which are coaxial. A front transition sleeve 141 and a rear transition sleeve 142 are coaxially fixedly installed in the front and rear through holes, respectively. The front transition sleeve and the front through hole form a front hinge interface structure, and the rear transition sleeve and the rear through hole form a rear hinge interface structure. When the rocker arm structure is hinged to the fixed gearbox, the free ends of the front and rear support arms can each cooperate with a double-ear structure seat and pass through a pin to achieve connection. Both ends of the front transition sleeve are sealed with the front support arm and the corresponding pin, and both ends of the rear transition sleeve are sealed with the rear support arm and the corresponding pin. In this embodiment, the outer cylindrical surface and the inner hole surface of the front transition sleeve are provided with annular sealing grooves at both axial ends, and the outer cylindrical surface and the inner hole surface of the rear transition sleeve are provided with annular sealing grooves at both axial ends. Sealing rings are provided in the sealing grooves to achieve the above-mentioned sealing.

[0036] The rocker arm structure can also be further optimized in any one or more of the following aspects:

[0037] 1. The front support arm and the rear support arm are respectively provided with a front automatic lubrication device 151 and a rear automatic lubrication device 152. The target lubrication points of the front automatic lubrication device and the rear automatic lubrication device are located on the inner hole surfaces of the front transition sleeve and the rear transition sleeve, respectively. By adding front and rear automatic lubrication devices at the connection points of the front and rear supports, automatic, effective, and long-term lubrication of the support force-bearing surfaces can be ensured, reducing wear and extending the service life of the support connection points. In the embodiment shown in the attached figure, the front automatic lubrication device and the rear automatic lubrication device are installed on the free ends of the front support arm and the rear support, respectively.

[0038] 2. The free end of the front support arm is also provided with a cylinder connecting lug 124 for hinged connection with one end of the height adjustment cylinder. Since the front hinge interface structure is usually located on the free end of the front support arm, the cylinder connecting lug is relatively close to the front hinge interface structure. That is, the lever arm for the height adjustment cylinder to drive the rocker arm to swing is shorter. Therefore, with the same stroke of the height adjustment cylinder, the rocker arm structure of the present invention can achieve a larger rocker arm swing angle and swing angle range, and a wider height range.

[0039] 3. The front support arm is L-shaped, and the free ends of the left and right extensions of the front support arm are the free ends of the front support arm. The rear ends of the front and rear extensions of the front support arm are connected to the transmission housing. The top surface of the front and rear extensions of the front support arm is an inclined plane 123, and the inclination direction of the inclined plane is such that the height decreases as it moves away from the free end of the front support arm. The distance from the highest point of the inclined plane to the hinge axis of the front hinge interface structure is preferably not greater than the distance from the top surface of the housing of the fixed gearbox to the hinge axis of the front hinge interface structure. The inclination angle of the inclined plane relative to the horizontal plane is preferably the angle between the transmission housing and the horizontal plane when the boom housing is in the upper cutter limit position, so that when the boom housing is in the upper cutter limit position, the entire front support arm is below the top surface of the housing of the fixed gearbox (see...). Figure 5 ).

[0040] 4. The rocker arm structure of the low-profile coal mining machine with a wide mining range also includes a roller 3. The roller is fitted onto the front and rear extensions of the transmission housing and coaxially connected to the transmission output interface structure. The vertical thickness of the front support arm is much smaller than the diameter of the roller to minimize the possibility of interference between the front support arm and the coal platform. The roller is installed by fitting it onto the cylindrical front and rear extensions of the transmission housing, and the front part of the roller is coaxially connected to the rear gear shaft through the roller positioning and mounting structure. The connection is simple, and it can accommodate rollers with very small diameters, thus adapting to the mining of low-seam coal seams and making maintenance more convenient.

[0041] 5. For example Figure 4 As shown, the top and bottom surfaces of the free end of the front support arm are preferably configured as outer cylindrical surfaces 121 and 122 coaxial with the hinge axis of the front hinge interface structure. When the rocker arm structure is connected to the fixed gearbox, correspondingly, two coaxial inner cylindrical surfaces 411 and 412 can be provided on the housing of the fixed gearbox to form a clearance fit with the two outer cylindrical surfaces on the front support arm. Compared with the open connection structure, this can effectively prevent dust and other impurities from entering the housing of the fixed gearbox from the free end of the front support arm, thus helping to ensure the cleanliness of the inner cavity of the fixed gearbox.

[0042] Based on this, when the cylinder connecting ear 124 is simultaneously installed on the free end of the current support arm, the partial inner cavity of the fixed gearbox closed by the free end of the previous support arm becomes the cylinder mounting cavity. The above-mentioned clearance fit can ensure the cleanliness of the cylinder mounting cavity, thus providing a good working environment for the swing of the height adjustment cylinder, making the swing more reliable and free.

[0043] This invention can significantly improve the reliability of the connection between the device and the fixed gearbox, achieve a lower lower limit and a higher upper limit for mining, while avoiding interference with the coal seam and meeting the mining requirements of coal seams below 1m.

Claims

1. A rocker arm structure for a low-profile coal mining machine with a wide mining range, characterized in that: The system includes a boom housing, which comprises an L-shaped transmission housing. The free ends of the left and right extensions of the transmission housing are provided with transmission input interface structures, and the front ends of the front and rear extensions of the transmission housing are provided with transmission output interface structures. A front support arm and a rear support arm are respectively provided at the front and rear of the left and right extensions of the transmission housing. Both the front and rear support arms are cantilever structures with one end connected to the transmission housing. The top surfaces of both the front and rear support arms are not higher than the top surface of the transmission housing, and the bottom surfaces of both the front and rear support arms are not lower than the bottom surface of the transmission housing. The front and rear support arms are respectively provided with a front hinge interface structure and a rear hinge interface structure. The hinge axis of the front hinge interface structure, the hinge axis of the rear hinge interface structure, and the rotation axis of the transmission input interface structure coincide, and like the rotation axis of the transmission output interface structure, they all extend in the front-rear direction.

2. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 1, characterized in that: The transmission housing is equipped with a rear-stage cutting transmission mechanism, which includes a rear-stage first gear, a rear-stage idler gear, and a rear-stage gear shaft arranged in sequence and meshing with each other. The core of the rear-stage first gear is provided with a spline hole, the opening of which is located on the front end face of the rear-stage first gear. The center line of the spline hole coincides with the center line of the rear-stage first gear, and the center line of the spline hole is the rotation axis of the transmission input interface structure.

3. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 2, characterized in that: The subsequent idler gear has one or more externally meshing gears in sequence.

4. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 3, characterized in that: The front support arm and the rear support arm are respectively provided with a front through hole and a rear through hole. The front through hole and the rear through hole are coaxial. The front transition sleeve and the rear transition sleeve are respectively coaxially fixedly installed in the front through hole and the rear through hole. The front transition sleeve and the front through hole form a front hinge interface structure, and the rear transition sleeve and the rear through hole form a rear hinge interface structure.

5. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 4, characterized in that: The front support arm and the rear support arm are respectively provided with a front automatic lubrication device and a rear automatic lubrication device, and the lubrication points of the front automatic lubrication device and the rear automatic lubrication device are respectively located on the inner hole surface of the front transition sleeve and the rear transition sleeve.

6. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 1, 2, 3, 4 or 5, characterized in that: The free end of the front support arm is also provided with a hydraulic cylinder connecting lug.

7. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 1, 2, 3, 4 or 5, characterized in that: The front support arm is L-shaped, and the free ends of the left and right extensions of the front support arm are the free ends of the front support arm. The rear ends of the front and rear extensions of the front support arm are connected to the transmission housing. The top surface of the front and rear extensions of the front support arm is an inclined surface, and the height decreases as it moves away from the free end of the front support arm.

8. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 7, characterized in that: It also includes a roller, which is sleeved on the front and rear extensions of the transmission housing and coaxially connected to the transmission output interface structure. The upper and lower thickness of the front support arm is smaller than the diameter of the roller.

9. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 1, 2, 3, 4 or 5, characterized in that: The top and bottom surfaces of the free end of the front support arm are configured as outer cylindrical surfaces coaxial with the hinge axis of the front hinge interface structure.

10. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 6, characterized in that: The top and bottom surfaces of the free end of the front support arm are configured as outer cylindrical surfaces coaxial with the hinge axis of the front hinge interface structure.

11. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 7, characterized in that: The top and bottom surfaces of the free end of the front support arm are configured as outer cylindrical surfaces coaxial with the hinge axis of the front hinge interface structure.

12. The rocker arm structure of a low-hull coal mining machine with a wide mining range as described in claim 8, characterized in that: The top and bottom surfaces of the free end of the front support arm are configured as outer cylindrical surfaces coaxial with the hinge axis of the front hinge interface structure.

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