Coal mining machine cutting system

Abstract

The present invention relates to a coal mining machine cutting system, including a fixed reduction box and an arm, the fixed reduction box includes a housing and a cutting motor and a front-stage cutting transmission mechanism arranged therein, the front-stage cutting transmission mechanism adopts a multi-stage large reduction ratio transmission mechanism combining a planetary mechanism and a fixed-axis gear transmission mechanism, the arm includes an arm housing and a rear-stage cutting transmission mechanism, the rear-stage cutting transmission mechanism adopts a one-stage small reduction ratio fixed-axis gear transmission mechanism, the core of the front-stage final gear of the front-stage cutting transmission mechanism and the rear-stage first gear of the rear-stage cutting transmission mechanism are respectively provided with a front-stage spline hole and a rear-stage spline hole, a spline sleeve with inner and outer splines is installed in the front-stage spline hole, and the inner spline of the spline sleeve and the rear-stage spline hole are respectively connected with the front and rear splines of the same spline shaft. The present invention can achieve a wider mining range, can adapt to the mining of low-mining coal seams, and can improve the center of gravity arrangement of the whole coal mining machine.

Description

Technical Field

[0001] The invention relates to a coal mining machine cutting system, which is suitable for coal mining machines with short bodies and wide mining ranges. Background Art

[0002] The rocker arm structure of the existing thin coal seam coal mining machine (especially the high-power rocker arm) usually adopts a conventional structure with independent power (see Figure 8 ), although the reliability is relatively high, the rocker arm structure is relatively complex, especially when the required mining lower limit is low, it is necessary to adopt the arrangement method in which the rocker arm is suspended relative to the conveyor trough. In this case, the rear rocker arm has a small amount of top picking and cannot adapt to the mining of coal seams with a larger upper limit.

[0003] In order to optimize the rocker arm structure, one practice in the industry is to set the cutting system into a fixed part containing power and a swinging part that outputs power. However, some designs, due to consideration of the structure of the loading channel, set part of the transmission of the fixed part above the conveyor trough, affecting the coal passing space; some rockers adopt a structure in which a planetary mechanism is set in a conventional roller, which makes it impossible to use a small-sized roller, thus limiting the lower limit of mining and affecting the mining of thin or extremely thin coal seams; some set the power and main deceleration part on the coal seam side in front of the conveyor trough (i.e. between the left and right rollers). Although the mining height can be lower, the transmission is relatively complex, and the center of gravity of the fixed part and the swinging part is relatively biased towards the coal wall, which has a certain adverse effect on the operation of the whole machine, especially under the conditions of the downward mining working face. Summary of the invention

[0004] The present invention aims to provide a coal mining machine cutting system, which has a wide mining range from low to high, can adapt to the mining of low mining height coal seams, and can improve the center of gravity arrangement of the coal mining machine.

[0005] The main technical solutions of the present invention are:

[0006] A coal mining machine cutting system comprises a fixed reduction box and a boom, wherein the fixed reduction box comprises a fixed reduction box housing, a cutting motor and a front-stage cutting transmission mechanism arranged in the fixed reduction box housing, wherein the output shaft of the cutting motor is connected to the front-stage cutting transmission mechanism, wherein the front-stage cutting transmission mechanism adopts a multi-stage large reduction ratio transmission mechanism combining a planetary mechanism and a fixed-axis gear transmission mechanism, wherein the output end of the front-stage cutting transmission mechanism is a front-stage final gear, wherein the boom comprises a boom housing and a rear-stage cutting transmission mechanism, wherein the boom housing comprises an L-shaped transmission housing, wherein the rear-stage cutting transmission mechanism adopts a first-stage small reduction ratio fixed-axis gear transmission mechanism, wherein the rear-stage first gear, the rear-stage idler gear and the rear-stage idler gear are meshed in sequence. A rear-stage gear shaft, wherein the rear-stage first gear is installed inside the free ends of the left and right extension sections of the transmission case, the free ends of the front and rear extension sections of the transmission case are cylindrical, the rear-stage gear shaft is installed in the front and rear extension sections of the transmission case and its terminal end extends forward and outward to expose the free ends of the front and rear extension sections, the terminal end of the rear-stage gear shaft is provided with a roller positioning and mounting structure, the core of the front-stage final gear and the core of the rear-stage first gear are respectively provided with a front-stage spline hole and a rear-stage spline hole, a spline sleeve with inner splines and outer splines is installed in the front-stage spline hole, the inner splines of the spline sleeve and the rear-stage spline hole are respectively connected with the front and rear splines of the same spline shaft, and the center line of the spline shaft extends horizontally front and back.

[0007] The arm housing also includes a front support arm and a rear support arm respectively located in front of and behind the left and right extension sections of the transmission case, the front support arm and the rear support arm are cantilever structures connected to the transmission case at one end, and one end of the front support arm and the rear support arm away from the front and rear extension sections of the transmission case is a free end, the top surfaces of the front support arm and the rear support arm are not higher than the top surfaces of the left and right extension sections of the transmission case, and the bottom surfaces of the front support arm and the rear support arm are not lower than the bottom surfaces of the left and right extension sections of the transmission case, the free ends of the front support arm and the rear support arm are respectively hinged to the fixed reduction box housing, and the hinge axis coincides with the center line of the spline shaft.

[0008] The fixed reduction box housing is provided with a front articulated seat and a rear articulated seat, both of which are double-ear seat structures. The free ends of the front support arm and the rear support arm respectively cooperate with the front articulated seat and the rear articulated seat and are respectively penetrated by a front pin shaft and a rear pin shaft to realize articulation.

[0009] The rear hinged ear of the front hinged seat is just embedded between the front support arm and the transmission box body and maintains a gap between the front support arm and the transmission box body. The front-stage final gear is installed in the rear hinged ear of the front hinged seat. An annular axial baffle is provided in the inner hole of the rear hinged ear of the front hinged seat. The front pin shaft is located in front of the axial baffle. The front-stage final gear and the spline sleeve are located behind the axial baffle. A central through hole is provided in the front pin shaft. The inner spline of the spline sleeve is arranged in the inner hole of its rear section. The front inner hole of the key sleeve is a light hole, and a positioning sleeve is fixedly installed in the central through hole. The rear end of the positioning sleeve is inserted into the light hole of the spline sleeve, and the front end face core of the spline shaft is axially limited. An annular flange is provided in the middle of the positioning sleeve, and the outer cylindrical surface of the annular flange is matched with the inner hole gap of the central through hole and the axial partition at the same time, and a seal is provided between the matching surfaces, and an end face seal is provided between the rear articulated ear of the front articulated seat and the rear-stage cutting transmission mechanism and / or the transmission box.

[0010] The front support arm is L-shaped, the free ends of the left and right extension sections of the front support arm are the free ends of the front support arm, the rear ends of the front and rear extension sections of the front support arm are connected to the transmission box, the top surfaces of the front and rear extension sections of the front support arm are inclined, and the height decreases as it is farther away from the free end.

[0011] The hinges between the front support arm and the rear support arm and the fixed reduction box housing are respectively lubricated by arranging a front automatic lubrication device and a rear automatic lubrication device.

[0012] The coal mining machine cutting system also includes a cylinder, one end of which is hinged to the fixed reduction box housing, a cylinder connecting ear is provided on the outside of the free end of the front support arm, the other end of the cylinder is hinged to the cylinder connecting ear, and the hinge axes at both ends of the cylinder extend horizontally forward and backward.

[0013] The oil cylinder and the front-stage cutting transmission mechanism are arranged in different chambers in the inner cavity of the fixed reduction gearbox housing. The oil cylinder is located in front of the front-stage cutting transmission mechanism. The chamber where the oil cylinder is located is surrounded by the fixed reduction gearbox housing, the front support arm, the front articulated seat and the side panel installed on the front side of the fixed reduction gearbox housing.

[0014] The free end of the front support arm is preferably provided with upper and lower outer cylindrical surfaces coaxial with the spline shaft, and the fixed reduction box housing is provided with upper and lower inner cylindrical surfaces coaxial with the spline shaft, and the two inner cylindrical surfaces are respectively matched with the two outer cylindrical surfaces in a clearance.

[0015] There is one cutting motor and one planetary mechanism, the output shaft of the cutting motor is coaxially connected to the input end of the planetary mechanism, the output end of the planetary mechanism is coaxially connected to a central gear, the central gear is meshed with the left and right sets of gear reduction mechanisms at the same time, and the central gear and the gear reduction mechanism constitute the fixed-axis gear transmission mechanism.

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

[0017] The front-stage cutting transmission mechanism transmits power to the rear-stage cutting transmission mechanism through a spline connection structure. Since a plurality of spline connection structures with side clearance are adopted, the radial floating amount is increased, and since the related parts forming the spline connection structure can be automatically centered, the radial deviation at both ends of the axial direction of the transmission parts caused by the wear of the rotating support surfaces has little effect on the transmission engagement, and the transmission structure between the front and rear-stage cutting transmission mechanisms has improved adaptability to the wear of the rotating support surfaces at both ends of the axial direction, so the reliability of power transmission between the rocker arm and the fixed reduction box can be significantly improved.

[0018] As the main deceleration part of the cutting system, the front-stage cutting transmission mechanism is arranged in the fixed reduction box housing and does not swing with the boom. What swings with the boom is a first-stage small reduction ratio fixed-axis gear transmission mechanism, and this mechanism is located behind the drum, so it does not affect the interference between the boom and the coal platform during the top picking operation.

[0019] Since heavier components such as planetary mechanisms are closer to the goaf side, the overall center of gravity of the coal mining machine can be shifted toward the goaf side, which is closer to the position of the supporting legs (or shovel plates) than the center of gravity of coal mining machines with traditional structures, thereby improving the stability of the coal mining machine in both stationary and walking states.

[0020] The drum can be installed by putting the drum on the front and rear extension sections of the cylindrical transmission box body, so that the front part of the drum is coaxially connected with the rear gear shaft through the drum positioning and installation structure. The connection is simple and can be matched with a very small diameter drum, so it can adapt to the mining of low-height coal seams and is more convenient to maintain.

[0021] Since multiple support connection points are set between the boom housing and the fixed reduction box housing, and these support connection points are respectively arranged in front of and behind the power transmission connection point, i.e., the spline connection structure, the radial displacement caused by wear at the front and rear support connection points has less impact on the power transmission connection point located between the two. Therefore, the support connection structure can provide more reliable guarantee for the transmission of cutting power.

[0022] By adding front automatic lubrication devices and rear automatic lubrication devices at the front and rear support connection points, automatic, effective and long-term lubrication of the support load-bearing surface can be guaranteed, wear can be reduced, and the service life of the support connection points can be extended.

[0023] The upper and lower thicknesses of the front support arm and the rear support arm are smaller than the transmission housing, and much smaller than the diameter of the matching roller, which can avoid the interference between the front support arm and the rear support arm and the top coal platform when the arm housing is in the upper cutting limit position, so that the mining height can be higher. For the mining of extremely thin or thin coal seams, the rocker arm structure of the present invention can achieve both a lower mining lower limit and a higher mining upper limit, thereby forming a wider mining range and being suitable for short-body coal mining machines.

[0024] The front-stage final gear is installed in the rear articulated ear of the front articulated seat, so that the front-stage cutting transmission mechanism and the front articulated structure share a shell, and the internal space of the shared shell is functionally partitioned by setting an axial baffle, so that the structure of the connection between the arm shell and the fixed reduction box shell is simplified and compact as much as possible. By setting the front pin shaft as a hollow structure, on the one hand, sufficient disassembly and assembly space is provided for the spline shaft, and the disassembly and assembly space is located on the side of the drum, which does not occupy the coal passage and does not affect the coal passing; on the other hand, when the coal mining machine rocker arm is in normal use, the disassembly and assembly space can be used to install a positioning structure to axially limit the spline shaft, achieving multiple goals at one stroke.

[0025] By arranging an end face seal between the rear articulated ear of the front articulated seat and the rear-stage cutting transmission mechanism and / or the transmission box, and arranging a seal at the clearance fit between the annular flange in the middle of the positioning sleeve and the central through hole of the front pin shaft, it is possible to effectively prevent impurities such as water and coal powder from entering the spline connection structure from the front and rear, thereby ensuring the cleanliness and lubrication of the spline connection structure, extending the service life of the spline connection structure, and improving the working reliability of the spline connection structure.

[0026] Since the cylinder connecting ear is relatively close to the hinge axis between the free end of the front support arm and the fixed reduction box housing, the force arm driving the boom housing to swing is shorter, and correspondingly the swing angle range of the boom housing is larger, which is equivalent to a wider range of achievable mining heights.

[0027] A cutting motor is used to drive the gear reduction mechanisms arranged on the left and right sides thereof, and transmit power to the left and right booms respectively, so as to make full use of the cutting power, improve the use efficiency and reduce the idling transmission motion loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic structural diagram of an embodiment of the present invention;

[0029] Figure 2 for Figure 1 A schematic diagram of the structure of the boom described in the embodiment of the present invention;

[0030] Figure 3 for Figure 2 AA section view;

[0031] Figure 4 for Figure 1 A schematic diagram of the structure of the fixed reduction gearbox;

[0032] Figure 5 It is an enlarged view of the power transmission structure between the front-stage cutting transmission mechanism and the rear-stage cutting transmission mechanism;

[0033] Figure 6 It is a schematic diagram of the clearance fit between the free end of the front support arm and the fixed reduction box housing;

[0034] Figure 7 It is a schematic diagram of the state of a coal mining machine adopting the cutting system of the present invention when the rear rocker arm is at the upper cutting limit position;

[0035] Figure 8 It is a schematic diagram of the state of a coal mining machine using an existing cutting system when the rear rocker arm is cutting.

[0036] Reference numerals:

[0037] 1. Boom; 11. Boom housing; 111. Transmission box; 112. Front support arm; 1121. Inclined surface; 1122. Cylinder connecting ear; 1123. Upper outer cylindrical surface; 1124. Lower outer cylindrical surface; 113. Rear support arm; 12. Front transition sleeve; 13. Rear transition sleeve; 14. Front automatic lubrication device; 15. Rear automatic lubrication device;

[0038] 2. Fixed reduction gearbox; 21. Fixed reduction gearbox housing; 211. Front hinge seat; 2111. Front hinge ear of front hinge seat; 2112. Rear hinge ear of front hinge seat; 2113. Upper inner cylindrical surface; 2114. Lower inner cylindrical surface; 212. Rear hinge seat; 213. Axial baffle; 22. Front pin shaft; 23. Rear pin shaft; 24. Front wear-resistant sleeve; 25. Rear wear-resistant sleeve; 26. Positioning sleeve; 27. Sealing ring; 28. Sealing ring; 29. ​​Side plate;

[0039] 3. Roller;

[0040] 4. Oil cylinder;

[0041] 5. Spline shaft;

[0042] 6. Spline sleeve;

[0043] 7. Cutting motor;

[0044] 81. Planetary mechanism; 82. Front stage final gear; 821. Front stage spline hole; 83. Central gear;

[0045] 91. Rear stage first gear; 911. Rear stage spline hole; 92. Rear stage idler gear; 93. Rear stage gear shaft. DETAILED DESCRIPTION

[0046] The present invention discloses a coal mining machine cutting system, such as Figure 1-7 As shown, it includes a fixed reduction box 2 and a boom 1, wherein the fixed reduction box includes a fixed reduction box housing 21 and a cutting motor 7 and a front-stage cutting transmission mechanism arranged in the fixed reduction box housing. The output shaft of the cutting motor is connected to the front-stage cutting transmission mechanism, and the front-stage cutting transmission mechanism adopts a multi-stage large reduction ratio transmission mechanism combining a planetary mechanism 81 and a fixed-axis gear transmission mechanism. The output end of the front-stage cutting transmission mechanism is a front-stage final gear 82, and the front-stage final gear is installed in the fixed reduction box housing through a bearing rotation support. The boom includes a boom housing 11 and a rear-stage cutting transmission mechanism. The boom housing includes an L-shaped transmission box body 111. The rear-stage cutting transmission mechanism adopts a one-stage small reduction ratio fixed-axis gear transmission mechanism, including a rear-stage first gear 91, a rear-stage idler gear 92 and a rear-stage gear shaft 93 that are meshed externally in sequence. The rear stage first gear is rotatably supported and installed inside the free ends of the left and right extension sections of the transmission case through bearings, and the rear stage idler is rotatably supported on the rear stage idler shaft through bearings, and the rear stage idler shaft is fixedly installed in the left and right extension sections of the transmission case. The free ends of the front and rear extension sections of the transmission case are cylindrical, and the rear stage gear shaft is installed in the front and rear extension sections of the transmission case, and its terminal end extends forward and outward to expose the free ends of the front and rear extension sections. The terminal end of the rear stage gear shaft is provided with a roller positioning and mounting structure for installing the roller 3. When installing the roller, the roller is sleeved on the front and rear extension sections of the transmission case, and the front part of the roller is coaxially connected with the rear stage gear shaft through the roller positioning and mounting structure. The core of the front stage final gear and the core of the rear stage first gear are respectively provided with a front stage spline hole 821 and a rear stage spline hole 911, and a spline sleeve 6 with internal splines and external splines is installed in the front stage spline hole, and the external splines of the spline sleeve match the front stage spline hole. The inner spline of the spline sleeve and the rear spline hole are respectively spline-connected with the front and rear of the same spline shaft 5, and the center line of the spline shaft extends horizontally front and back. The rotation of the front end gear drives the spline sleeve to rotate, the spline sleeve drives the spline shaft to rotate, and the spline shaft drives the rear first gear to rotate, thereby realizing the transmission of power from the front cutting transmission mechanism to the rear cutting transmission mechanism.

[0047] A primary spline transmission is formed between the front stage final gear and the spline sleeve, and a secondary spline transmission is formed between the spline sleeve and the spline shaft, and between the spline shaft and the rear stage first gear. Since multiple spline connection structures with side clearance are adopted, the radial floating amount is increased, and since the related parts forming the spline connection structure can be automatically centered, the radial offset caused by the wear of the rotating support surface at both ends of the axial direction of the transmission parts has little effect on the transmission meshing, or in other words, the transmission structure between the front and rear stage cutting transmission mechanisms has improved adaptability to the wear of the rotating support surfaces at both ends of the axial direction, so the reliability of power transmission between the rocker arm and the fixed reduction box can be significantly improved.

[0048] As the main deceleration part of the cutting system, the front-stage cutting transmission mechanism is arranged in the fixed reduction box housing and does not swing with the boom. What swings with the boom is a first-stage fixed-axis gear transmission mechanism with a small reduction ratio, and this mechanism is located behind the drum, so it does not affect the interference between the boom and the coal platform during the top picking operation. Since the position where the drum 3 is installed is only the free end of the front and rear extension sections of the cylindrical transmission box and the exposed end of the rear-stage gear shaft, the connection structure is simple and can be matched with a very small diameter drum, so it can adapt to the mining of low-height coal seams and is more convenient for maintenance.

[0049] In the embodiment shown in the accompanying drawings, the rear end of the front stage final gear is supported on the front bearing seat through a bearing, the front bearing seat is installed on the fixed reduction box housing, and the front end of the rear stage first gear is supported on the rear bearing seat through a bearing, and the rear bearing seat is installed on the arm housing.

[0050] The arm housing 11 may also include a front support arm 112 and a rear support arm 113 located in front of and behind the left and right extension sections of the transmission housing 111, respectively. The front support arm and the rear support arm are both cantilever structures with one end connected to the transmission housing. One end of the front support arm and the rear support arm away from the front and rear extension sections of the transmission housing is a free end. The top surface of the front support arm and the rear support arm is preferably not higher than the top surface of the left and right extension sections of the transmission housing, and the bottom surface of the front support arm and the rear support arm is preferably not lower than the bottom surface of the left and right extension sections of the transmission housing, that is, the upper and lower thicknesses of the front support arm and the rear support arm are both smaller than the transmission housing, which can avoid the interference of the front support arm and the rear support arm with the top coal platform when the arm housing is in the upper cutting limit position as much as possible, so that the mining height can be higher. For the mining of extremely thin or thin coal seams, the rocker arm of the present invention can meet both the lower mining limit and the higher mining limit, so that a wider mining range can be formed, which can be applied to short-body coal mining machines.

[0051] The free end of the front support arm and the free end of the rear support arm are respectively hinged to the fixed reduction box housing, and the hinge axis coincides with the center line of the spline shaft.

[0052] In this embodiment, the front support arm, the rear support arm and the transmission box are an integrated structure.

[0053] Since the support connection points formed between the boom housing and the fixed reduction box housing are located in front of and behind the power transmission connection points of the front and rear cutting transmission mechanisms, respectively, the radial displacement caused by wear at the front and rear support connection points has less impact on the power transmission connection point between the two, so the support connection structure can provide a more reliable guarantee for the transmission of cutting power. On the other hand, the average force point of the drum is located between the front and rear support connection points, and the force state of the boom housing is better.

[0054] A front articulated seat 211 and a rear articulated seat 212 are correspondingly provided on the fixed reduction box housing. The front articulated seat and the rear articulated seat are both double-ear seat structures. The free ends of the front support arm and the rear support arm respectively cooperate with the front articulated seat and the rear articulated seat and are respectively penetrated by a front pin shaft 22 and a rear pin shaft 23 to achieve articulation.

[0055] 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, and the front transition sleeve 12 and the rear transition sleeve 13 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. A pair of front wear-resistant sleeves 24 and a pair of rear wear-resistant sleeves 25 are respectively fixedly installed in the ear holes of the front hinge seat and the rear hinge seat. The front pin passes through the front transition sleeve and the front wear-resistant sleeve, and the rear pin passes through the rear transition sleeve and the rear wear-resistant sleeve. The front pin and the rear pin are respectively clearance-matched with the front transition sleeve and the rear transition sleeve. The front pin and the rear pin are respectively tightly matched with the front wear-resistant sleeve and the rear wear-resistant sleeve.

[0056] The rear hinge ear 2112 of the front hinge seat is just embedded between the front support arm and the transmission box, and a gap is maintained between the front support arm and the transmission box to ensure relative swing with the arm frame housing. The front stage final gear is installed in the rear hinge ear of the front hinge seat. An annular axial baffle 213 is provided in the inner hole of the rear hinge ear of the front hinge seat, the front pin is located in front of the axial baffle, and the front stage final gear and the spline sleeve are located behind the axial baffle. In this embodiment, the axial baffle is a part of the entity of the rear hinge ear of the front hinge seat, and is a circular ring structure protruding radially toward the center of the ear hole. A central through hole is provided in the front pin. The inner spline of the spline sleeve 6 is arranged in the rear section inner hole of the spline sleeve, and the front section inner hole is a light hole. A positioning sleeve 26 is fixedly installed in the central through hole, and the positioning sleeve is cup-shaped, and the rear end is a sealing end. The sealing end (i.e., the rear end) of the positioning sleeve is inserted into the light hole of the spline sleeve through the axial baffle, and the core of the front end face of the spline shaft 5 is axially limited. In this embodiment, a wear-resistant pad is fixed to the rear end of the positioning sleeve, and the positioning sleeve axially limits the spline shaft with the help of the wear-resistant pad. The spline shaft contacts and rotates relative to the wear-resistant pad. The positioning sleeve is axially limited in the central through hole by the front end cover fixed on the front hinge ear 2111 of the front hinge seat. The positioning sleeve does not contact the spline sleeve. An annular flange is provided in the middle of the positioning sleeve, and the outer cylindrical surface of the annular flange is matched with the inner hole gap of the central through hole and the axial baffle at the same time, and a seal is provided between the matching surfaces. In this embodiment, a sealing groove is provided on the outer cylindrical surface of the annular flange, in which a sealing ring 27 is installed, and the sealing between the positioning sleeve and the front pin shaft and the rear hinge ear of the front hinge seat is achieved through the sealing ring, so as to prevent impurities such as water and coal powder from entering the spline connection structure from the front end.

[0057] An end face seal is provided between the rear hinge ear 2112 of the front hinge seat and the rear-stage cutting transmission mechanism and / or the left and right extension sections of the transmission housing (for example, a sealing groove is provided on the front end face of the transmission housing and a sealing ring 28 is installed) to prevent impurities such as water and coal powder from entering the spline connection structure from the rear end. In the embodiment shown in the drawings, the end face seal is provided at the joint between the front end face of the rear bearing seat and the front end face of the transmission housing.

[0058] The seal between the annular flange and the central through hole and the axial baffle and the aforementioned end face seal can ensure the cleanliness and original lubrication of the spline connection structure, thereby increasing the service life of the spline connection structure.

[0059] When the spline shaft is worn, the positioning sleeve 26 can be removed from the front side to free up the cylindrical space in front of the spline shaft 5, and the spline shaft can be smoothly disassembled and replaced. In addition, the cylindrical space is located on the side of the drum and does not occupy the upper space of the coal passage of the conveying trough, so it does not affect coal passing and mining.

[0060] In the embodiment shown in the attached drawings, the ear hole of the front hinge ear of the rear hinge seat is a blind hole with an open rear end, and a rear end cover is fixedly mounted on the rear hinge ear of the rear hinge seat, and the blind ear hole and the rear end cover axially limit the rear pin shaft. The rear end of the rear stage first gear is directly supported on the transmission housing through a bearing, and the rear side of the free end of the transmission housing is not through, which can reduce dust and other impurities from entering between the parts with relative motion, and try to maintain a good relative motion state of the related parts.

[0061] The rear-stage spline hole is preferably a blind hole, the opening of which is on the front end face of the rear-stage first gear, and the bottom surface of the rear-stage spline hole is the positioning surface of the rear end face of the spline shaft.

[0062] The front support arm is L-shaped, and the free ends of the left and right extensions of the front support arm are also the free ends of the front support arm, and the rear ends of the front and rear extensions of the front support arm are connected to the transmission box. The top surface of the front and rear extensions of the front support arm is preferably a slope 1121, and the farther away from the free end, the lower the height, that is, the closer to the drum, the lower the height. The distance from the highest point of the slope to the hinge axis between the free end of the front support arm and the fixed reduction box housing is preferably not greater than the distance from the top surface of the housing of the fixed reduction box to the hinge axis, and the inclination angle of the slope relative to the horizontal plane is preferably the angle of the transmission box relative to the horizontal plane when the boom housing is in the upper knife limit position, so that when the boom housing is in the upper knife limit position, the entire front support arm is below the top surface of the housing of the fixed reduction box (see Figure 7 ).

[0063] The hinges of the front support arm and the rear support arm with the fixed reduction box housing can also be lubricated by respectively arranging a front automatic lubrication device 14 and a rear automatic lubrication device 15. The target lubrication points of the front automatic lubrication device and the rear automatic lubrication device can be located on the inner hole surfaces of the front transition sleeve and the rear transition sleeve, respectively. By adding the front automatic lubrication device and the rear automatic lubrication device at the front and rear support connection points, the automatic, effective and long-term lubrication of the support force surface can be ensured, the wear can be reduced, and the service life of the support connection points can be extended.

[0064] Further, seals are provided between the two ends of the front transition sleeve and the front support arm and the front pin shaft, and seals are provided between the two ends of the rear transition sleeve and the rear support arm and the rear pin shaft. In this embodiment, annular sealing grooves are provided at both ends of the axial direction of the outer cylindrical surface and the inner hole surface of the front transition sleeve, and annular sealing grooves are provided at both ends of the axial direction of the outer cylindrical surface and the inner hole surface of the rear transition sleeve, and sealing rings are provided in the sealing grooves to achieve the above-mentioned sealing.

[0065] The coal mining machine cutting system also includes a cylinder 4, one end of which is hinged on the fixed reduction box housing, a cylinder connecting ear 1122 is provided on the outside of the free end of the front support arm, and the other end of the cylinder is hinged on the cylinder connecting ear, and the hinge shafts at both ends of the cylinder extend horizontally forward and backward. The boom housing is driven to swing along a fixed axis by the extension and contraction of the cylinder. Since the cylinder connecting ear in this structure is relatively close to the hinge axis between the free end of the front support arm and the fixed reduction box housing, the force arm driving the boom housing to swing is shorter, and accordingly the swing angle range of the boom housing is larger, which is equivalent to a wider range of mining heights that can be achieved.

[0066] The oil cylinder and the front-stage cutting transmission mechanism are arranged in different chambers in the inner cavity of the fixed reduction box housing. The oil cylinder is located in front of the front-stage cutting transmission mechanism. Compared with the arrangement in which the oil cylinder is located behind the front-stage cutting transmission mechanism, since the heavier parts such as the planetary mechanism are closer to the goaf side, the overall center of gravity of the coal mining machine can be shifted to the goaf side, which is closer to the position of the support leg (or shovel plate) than the center of gravity of the coal mining machine with a traditional structure, so that the stability of the coal mining machine in both the static state and the walking state is improved. The chamber where the oil cylinder is located is surrounded by the fixed reduction box housing, the front support arm, the front articulated seat and the side plate 29 installed on the front side of the fixed reduction box housing. Placing the oil cylinder in an independent chamber can provide a good working environment for the swing of the oil cylinder and improve the reliability of the oil cylinder operation.

[0067] Furthermore, the free end of the front support arm is preferably provided with upper and lower outer cylindrical surfaces 1123 and 1124 coaxial with the spline shaft, and the fixed reduction box housing is provided with upper and lower inner cylindrical surfaces 2113 and 2114 coaxial with the spline shaft, and the two inner cylindrical surfaces are respectively matched with the two outer cylindrical surfaces (see Figure 6), which helps prevent dust and other impurities from entering the housing of the fixed reduction box from the free end of the front support arm, thereby helping to ensure the cleanliness of the inner cavity of the chamber where the oil cylinder is located.

[0068] The cutting motor 7 and the planetary mechanism 81 are each provided with one, and the output shaft of the cutting motor is coaxially connected to the input end of the planetary mechanism, and the output end of the planetary mechanism is coaxially connected to a central gear 83, and the central gear is meshed with the left and right gear reduction mechanisms for transmission. The central gear and the gear reduction mechanism constitute the fixed-axis gear transmission mechanism. A cutting motor is used to drive the gear reduction mechanisms arranged on its left and right sides, respectively, and transmit power to the left and right booms, respectively, so that the cutting power can be fully utilized, the use efficiency can be improved, and the idling transmission motion loss can be reduced. In the embodiment shown in the accompanying drawings, the output shaft of the cutting motor is coaxially connected to the sun gear of the planetary mechanism, and the planetary carrier of the planetary mechanism is coaxially connected to the central gear. The central gear is shared by the left and right gear reduction mechanisms.

[0069] The front in this article refers to the direction closer to the coal wall during coal mining operations.

Claims

1. A coal mining machine cutting system, characterized in that: It includes a fixed reduction box and a boom, the fixed reduction box includes a fixed reduction box housing and a cutting motor and a front-stage cutting transmission mechanism arranged in the fixed reduction box housing, the output shaft of the cutting motor is connected to the front-stage cutting transmission mechanism, the front-stage cutting transmission mechanism adopts a multi-stage large reduction ratio transmission mechanism combining a planetary mechanism and a fixed-axis gear transmission mechanism, the output end of the front-stage cutting transmission mechanism is a front-stage final gear, the boom includes a boom housing and a rear-stage cutting transmission mechanism, the boom housing includes an L-shaped transmission box body, the rear-stage cutting transmission mechanism adopts a first-stage small reduction ratio fixed-axis gear transmission mechanism, including a rear-stage first gear, a rear-stage idler gear and a rear-stage gear shaft that are externally meshed in sequence, and the rear-stage first gear is installed on the left and right sides of the transmission box body Inside the free end of the extension section, the free ends of the front and rear extension sections of the transmission case are cylindrical, the rear-stage gear shaft is installed in the front and rear extension sections of the transmission case and its terminal end extends forward and outward to expose the free ends of the front and rear extension sections, the terminal end of the rear-stage gear shaft is provided with a roller positioning and mounting structure, the core of the front-stage final gear and the core of the rear-stage first gear are respectively provided with a front-stage spline hole and a rear-stage spline hole, a spline sleeve with internal splines and external splines is installed in the front-stage spline hole, the internal splines of the spline sleeve and the rear-stage spline hole are respectively connected with the front and rear splines of the same spline shaft, and the center line of the spline shaft extends horizontally front and back; the arm housing also includes a front support arm and a rear support arm respectively located in front of and behind the left and right extension sections of the transmission case, The front support arm and the rear support arm are both cantilever structures connected to the transmission box body at one end, and one end of the front support arm and the rear support arm, which are away from the front and rear extension sections of the transmission box body, is a free end; a front hinge seat and a rear hinge seat are provided on the fixed reduction box housing, and the front hinge seat and the rear hinge seat are both double-ear ear seat structures, and the free ends of the front support arm and the rear support arm respectively cooperate with the front hinge seat and the rear hinge seat and are respectively penetrated by the front pin shaft and the rear pin shaft to achieve articulation, and the articulation axis and the center line of the spline shaft coincide; the rear articulation ear of the front articulation seat is just embedded between the front support arm and the transmission box body and maintains a gap between the front support arm and the transmission box body, the front-stage final gear is installed in the rear articulation ear of the front articulation seat, and the rear An annular axial baffle is provided in the inner hole of the hinged ear, the front pin shaft is located in front of the axial baffle, the front-stage final gear and the spline sleeve are located behind the axial baffle, a central through hole is provided in the front pin shaft, the inner spline of the spline sleeve is arranged in the inner hole of its rear section, the front inner hole of the spline sleeve is a light hole, a positioning sleeve is installed in the central through hole, the rear end of the positioning sleeve is inserted into the light hole of the spline sleeve, and the front end face core of the spline shaft is axially limited, an annular flange is provided in the middle part of the positioning sleeve, the outer cylindrical surface of the annular flange is simultaneously matched with the inner hole gap of the central through hole and the axial baffle, and a seal is provided between the matching surfaces, and an end face seal is provided between the rear hinged ear of the front hinged seat and the rear-stage cutting transmission mechanism and / or the transmission box.

2. The coal mining machine cutting system according to claim 1, characterized in that: The top surfaces of the front support arm and the rear support arm are not higher than the top surfaces of the left and right extension sections of the transmission box body, and the bottom surfaces of the front support arm and the rear support arm are not lower than the bottom surfaces of the left and right extension sections of the transmission box body.

3. The coal mining machine cutting system according to claim 2, characterized in that: The front support arm is L-shaped, the free ends of the left and right extension sections of the front support arm are the free ends of the front support arm, the rear ends of the front and rear extension sections of the front support arm are connected to the transmission box, the top surfaces of the front and rear extension sections of the front support arm are inclined, and the height decreases as it is farther away from the free end.

4. The coal mining machine cutting system according to claim 2, characterized in that: The hinges between the front support arm and the rear support arm and the fixed reduction box housing are respectively lubricated by arranging a front automatic lubrication device and a rear automatic lubrication device.

5. The coal mining machine cutting system according to claim 2, 3 or 4, characterized in that: It also includes a cylinder, one end of which is hinged on the fixed reduction box housing, a cylinder connecting ear is provided on the outside of the free end of the front support arm, the other end of the cylinder is hinged on the cylinder connecting ear, and the hinge axes at both ends of the cylinder extend horizontally forward and backward.

6. The coal mining machine cutting system according to claim 5, characterized in that: The oil cylinder and the front-stage cutting transmission mechanism are arranged in different chambers in the inner cavity of the fixed reduction gearbox housing. The oil cylinder is located in front of the front-stage cutting transmission mechanism. The chamber where the oil cylinder is located is surrounded by the fixed reduction gearbox housing, the front support arm, the front articulated seat and the side panel installed on the front side of the fixed reduction gearbox housing.

7. The coal mining machine cutting system according to claim 6, characterized in that: The free end of the front support arm is provided with upper and lower outer cylindrical surfaces coaxial with the spline shaft, and the fixed reduction box housing is provided with upper and lower inner cylindrical surfaces coaxial with the spline shaft, and the two inner cylindrical surfaces are respectively matched with the two outer cylindrical surfaces in clearance.

8. The coal mining machine cutting system according to claim 2, 3 or 4, characterized in that: There is one cutting motor and one planetary mechanism, the output shaft of the cutting motor is coaxially connected to the input end of the planetary mechanism, the output end of the planetary mechanism is coaxially connected to a central gear, the central gear is meshed with the left and right sets of gear reduction mechanisms at the same time, and the central gear and the gear reduction mechanism constitute the fixed-axis gear transmission mechanism.

9. The coal mining machine cutting system according to claim 5, characterized in that: There is one cutting motor and one planetary mechanism, the output shaft of the cutting motor is coaxially connected to the input end of the planetary mechanism, the output end of the planetary mechanism is coaxially connected to a central gear, the central gear is meshed with the left and right sets of gear reduction mechanisms at the same time, and the central gear and the gear reduction mechanism constitute the fixed-axis gear transmission mechanism.

10. The coal mining machine cutting system according to claim 6, characterized in that: There is one cutting motor and one planetary mechanism, the output shaft of the cutting motor is coaxially connected to the input end of the planetary mechanism, the output end of the planetary mechanism is coaxially connected to a central gear, the central gear is meshed with the left and right sets of gear reduction mechanisms at the same time, and the central gear and the gear reduction mechanism constitute the fixed-axis gear transmission mechanism.

11. The coal mining machine cutting system according to claim 7, characterized in that: There is one cutting motor and one planetary mechanism, the output shaft of the cutting motor is coaxially connected to the input end of the planetary mechanism, the output end of the planetary mechanism is coaxially connected to a central gear, the central gear is meshed with the left and right sets of gear reduction mechanisms at the same time, and the central gear and the gear reduction mechanism constitute the fixed-axis gear transmission mechanism.

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