Thin seam short span coal cutter

Abstract

The invention relates to a thin seam short span coal mining machine, which comprises front and rear main body part housings fixedly connected front and rear, and two swing arm housings respectively hinged at the left and right ends of the front main body part housing, the swing arm housings and the front main body part housing are hinged with a cutting motor as a hinge pin shaft, the left and right extending arm frames of the swing arm housings are respectively high speed ends and low speed ends, the middle part of the arm frame is provided with a connecting arm which is suspended forward from the arm frame, the connecting arm is provided with a front arm which is suspended leftward or rightward, the front arm and the front part of the high speed end of the arm frame are respectively provided with front and rear pin shaft mounting holes, the rear part of the high speed end of the arm frame is provided with an input end gear mounting hole, the front and rear pin shaft mounting holes are coaxial with the input end gear, the lower part of the front arm and the lower part of the connecting arm are provided with a hydraulic cylinder accommodating cavity, the two ends of a height adjusting hydraulic cylinder in the hydraulic cylinder accommodating cavity are respectively hinged to the connecting arm and the front main body part housing. The invention can provide a larger mining range and a larger cutting power, and can also shorten the machine body and improve the center of gravity of the coal mining machine.

Description

TECHNICAL FIELD

[0001] The present application relates to a coal mining machine, especially a thin seam short span coal mining machine, which has a large mining range and a large cutting power. BACKGROUND

[0002] On the existing thin seam coal mining machine, the cutting motor is usually located on the swing arm and swings with the swing arm. When the rear swing arm of the thin seam suspended body coal mining machine cuts the upper cutter in the direction of travel, the problem of too small rear drum mining height occurs. The reason is that when the mining height is increased, the rear swing arm cutting motor will interfere with the upper coal table left after the front drum cutting bottom cutter, so the overall mining height of this coal mining machine is too narrow and cannot adapt to the mining requirements of large changes in the thickness of the seam in the thin seam working face in China.

[0003] In view of the above problems, the industry has proposed to divide the cutting part into a swing part and a fixed part, and to set the cutting motor and the main part of the cutting transmission system in the fixed part, which leads to a too complex structure of the fixed part, a too long length and a too large weight of the suspended section of the machine body, and the center of gravity of the whole machine still has a great influence on the stress of the whole machine. Moreover, the long machine body structure of the coal mining machine cannot perform the straight pushing cutter process similar to the short wall coal mining machine, and the time for cutting the cutter at both ends is long, which has certain restrictions on the mining efficiency. SUMMARY

[0004] The present application aims to provide a thin seam short span coal mining machine which can provide a large mining range, a large cutting power, and also help to shorten the machine body and improve the center of gravity problem of the coal mining machine.

[0005] The main technical solutions of the present application are as follows:

[0006] The thin seam short span coal mining machine comprises a front main body part shell and two swing arm shells hingedly connected to the left and right ends of the front main body part shell, a cutting motor is arranged between each swing arm shell and the front main body part shell as a hinge pin shaft, the cutting motor is fixed relative to the front main body part shell, the main body of the swing arm shell is an arm support extending leftward and rightward, a cutting transmission mechanism is arranged in the arm support, the input end gear and the output end gear of the cutting transmission mechanism are arranged at the high speed end and the low speed end of the arm support respectively, a connecting arm extending forward from the arm support is arranged at the middle part of the arm support, a front arm extending leftward or rightward from the connecting arm is arranged on the connecting arm, a front pin shaft mounting hole and a rear pin shaft mounting hole are arranged on the front arm and the high speed end of the arm support respectively, the input end gear is arranged at the rear part of the high speed end of the arm support, the front pin shaft mounting hole and the rear pin shaft mounting hole are coaxial with the input end gear, the cutting motor is arranged in the front pin shaft mounting hole and the rear pin shaft mounting hole, the output shaft of the cutting motor is coaxially connected with the input end gear of the corresponding side, the lower part of the connecting arm is provided with an oil cylinder accommodating cavity extending leftward and rightward and opening downward, the oil cylinder accommodating cavity is arranged below the front arm in the front-rear direction, an adjusting height oil cylinder is arranged in the oil cylinder accommodating cavity, one end of the adjusting height oil cylinder is hingedly connected to the connecting arm, and the other end of the adjusting height oil cylinder is hingedly connected to the front main body part shell, and the hinge axes are all front-rear extending.

[0007] The middle upper part of the connecting arm is the narrowest in the left-right width in the height direction, and the left-right width becomes wider as it is closer to the upper and lower ends, the top surface of the connecting arm is a slope, and the top surface of the connecting arm is higher as it is closer to the high speed end of the same side arm support in the left-right direction.

[0008] A set of bearings are arranged in each front pin shaft mounting hole and rear pin shaft mounting hole, and the shell of each cutting motor is rotatably supported in the front pin shaft mounting hole and the rear pin shaft mounting hole on the same side through the bearings.

[0009] The bearings are joint bearings, a wear-reducing layer is arranged between the inner ring and the outer ring of the joint bearing, a sealing seat is arranged on the radially outer side of the inner ring and the front and rear ends of the outer ring respectively, a sealing groove is arranged on the radially inner hole surface and the outer end surface of the sealing seat, and a sealing ring is arranged in the sealing groove.

[0010] The left and right ends of the front main body part shell are each provided with a first ear seat, a second ear seat and a connecting base arranged in sequence from front to back, the front recess is formed between the first ear seat and the second ear seat, the rear recess is formed between the second ear seat and the connecting base, the front arm and the high speed end of the arm support on the same swing arm shell are respectively inserted into the front recess and the rear recess on the same side, and each cutting motor is arranged in the inner hole formed by the ear hole of the first ear seat, the front pin shaft mounting hole, the ear hole of the second ear seat and the rear pin shaft mounting hole on the same side.

[0011] The overhanging end outer surface of the front arm and the high-speed end outer surface of the arm frame on the same swing arm shell are provided as a first set of convex circular arc cylindrical surfaces coaxial with the front pin shaft mounting hole, the front and rear grooves on the same side are provided as a first set of concave circular arc cylindrical surfaces coaxial with the front pin shaft mounting hole, and the first set of concave circular arc cylindrical surfaces are coaxial with the first set of convex circular arc cylindrical surfaces and are spaced from each other; the side surface of the connecting arm near the high-speed end of the arm frame is provided as a second set of concave circular arc cylindrical surfaces coaxial with the front pin shaft mounting hole, and the overhanging end outer surfaces of the first and second ear seats on the same side are provided as a second set of convex circular arc cylindrical surfaces coaxial with the front pin shaft mounting hole, and the second set of convex circular arc cylindrical surfaces are coaxial with the second set of concave circular arc cylindrical surfaces and are spaced from each other.

[0012] The thin coal seam short span mining machine further comprises a clutch mechanism, the clutch mechanism comprises a mandrel and a clutch device, the clutch device is connected in front of the mandrel, the front part of the mandrel is provided with a front spline shaft section, the rear part of the mandrel is provided with a rear spline shaft section and a guide shaft section, the spline shaft section is located in front of the guide shaft section, the core of the input end gear is provided with a gear spline hole and a guide hole in front and back, the front part of the output shaft of the cutting motor is provided with a motor spline hole, when the clutch device is located at the rear limit position, the front spline shaft section and the rear spline shaft section of the mandrel are respectively spline-coupled with the motor spline hole and the gear spline hole, and the front part of the guide shaft section is located in the guide hole, and a radial gap is left between the guide shaft section and the guide hole.

[0013] The thin coal seam short span mining machine further comprises a rear main body part shell, the front main body part shell is fixedly connected in the middle of the left and right sides of the front side of the rear main body part shell, the front main body part shell is a multi-chamber thin-walled frame structure, the rear main body part shell is a solid structure, and the left and right ends of the rear main body part shell each extend to the rear of the low-speed end of the left and right arm frames.

[0014] The rear main body part shell is provided with two coal flow rear passages in the left and right directions, the coal flow rear passage is a groove extending from front to back and having a downward notch, the groove is located at the front part of the rear main body part shell, and the front end of the groove is open and the rear end is closed.

[0015] The thin coal seam short span mining machine further comprises support sliding shoes, the support sliding shoes are located at the rear of the low-speed end of the arm frame, the support sliding shoes are fixedly connected with the rear main body part shell, and the two coal flow rear passages in the left and right directions are located on the inner sides of the two support sliding shoes.

[0016] The thin coal seam short span mining machine has the following beneficial effects:

[0017] The swing arm of the present application can be hinged to the front part of the mining machine body with the cutting motor as a pin shaft, the left and right lengths of the front main body part are shortened, which is equivalent to shortening the left and right lengths of the suspension body section of the mining machine, the center of gravity of the mining machine body moves to the goaf side, and the stress stability of the whole mining machine is improved.

[0018] The swing arm of the present application can be hinged to the front part of the shearer body with the cutting motor as the pin shaft, and the connection arm on the inner side of the upper roller only connects the swing arm to swing up and down, the thin structure of the connection arm and the special top surface slope structure make the swing arm housing swing up and down without affecting the coal table above, thus ensuring a large mining range.

[0019] The swing arm of the present application can be hinged to the front part of the shearer body with the cutting motor as the pin shaft, and the main reduction part of the swing arm is provided with a planetary reduction mechanism in the roller, so that only a relatively simple cutting transmission mechanism (such as a two-stage fixed shaft gear transmission mechanism) needs to be provided in the swing arm, the arm frame has a more regular shape, and the cutting motor and the cutting transmission mechanism form a cutting mechanism with simple structure and compact size in the left-right direction.

[0020] The present application adopts two cutting motors arranged on the left and right of the front body part to drive the left and right swing arms, and the overall cutting power is larger than that of a single motor, which can reduce the continuous power consumption of the single motor when cutting hard materials in both directions, and the use of two motors for left and right auxiliary power operation can improve the overall reliability of the cutting mechanism power, especially when cutting hard materials.

[0021] The height-adjusting oil cylinder is arranged below the cutting motor, which not only makes full use of the space between the roof and the floor of the coal mining face, but also greatly shortens the length of the suspension body section in the left-right direction without occupying additional left-right longitudinal space, which shortens the distance between the two rollers for the double-roller shearer and facilitates the layout of the short body. The arrangement of the oil cylinder cavity provides a relatively clean working space for the swing of the height-adjusting oil cylinder and the layout of the oil cylinder pipeline, ensuring the free extension and swing of the height-adjusting oil cylinder and the free swing of the swing arm housing without being affected by coal and other mining materials, and finally ensuring that the maximum mining range is not affected.

[0022] The front arm, as the main supporting force part, is separated from the arm frame where the cutting transmission mechanism is installed, and the front part of the high-speed end of the arm frame, although it is part of the arm frame, only serves as a secondary force part for auxiliary support, so it can basically ensure that the cutting transmission mechanism is in a good non-stressed state, ensuring the transmission accuracy.

[0023] The cutting transmission mechanism and the rear pin shaft mounting hole for auxiliary supporting the cutting motor are arranged in the arm frame, which not only has a more compact structure, but also makes the power input connection point of the cutting transmission mechanism and the auxiliary support point closer, so that the power transmission is less affected by the jumping and more stable and reliable.

[0024] By installing support slippers behind the drum's rotation center and above the shovel, the coal flow on both the inner and outer sides of the drum's center is separated, reducing the impact of the coal flow outside the drum's centerline on the coal flow inside when the coal mining machine moves. The support slippers, combined with the rear coal flow channel, facilitate the entry of the coal flow inside the drum into the conveying trough, thereby improving the coal loading efficiency.

[0025] The rotatable connection between the swing arm housing and the front main body housing is set with multiple pairs of coaxial, equally spaced intervals. As long as the size of the corresponding intervals is controlled within a suitable range, the accumulation of coal and rock between the swing arm housing and the front main body housing can be effectively controlled during the swinging process of the swing arm housing relative to the front main body housing, avoiding jamming and ensuring the free rotation of the swing arm.

[0026] The front main body shell is a multi-chamber thin-walled frame structure, while the rear main body shell is a solid structure. The front and rear main body shells together form the coal mining machine body. The body is narrow at the front and wide at the rear, and open at the front and solid at the rear, which shifts the center of gravity of the machine body to the rear, improving the overall stability of the coal mining machine. Attached Figure Description

[0027] Figure 1 This is a top sectional view of an embodiment of the coal mining machine of the present invention;

[0028] Figure 2 This is a schematic diagram of the coal mining machine of the present invention in the working state of moving to the left and cutting coal;

[0029] Figure 3 This is a side view of an embodiment of the coal mining machine of the present invention;

[0030] Figure 4 A schematic diagram of the connection and support structure between the swing arm and the front main body shell;

[0031] Figure 5 for Figure 4 A top-view sectional view;

[0032] Figure 6 for Figure 1 Schematic diagram of the structure of the swing arm housing;

[0033] Figure 7 for Figure 1 Schematic diagram of the structure of the front and middle main body shell;

[0034] Figure 8 for Figure 1 Schematic diagram of the connection structure between the front and rear main body shells.

[0035] Figure label:

[0036] 1. swing arm; 11. swing arm housing; 111. front arm; 1111. outer surface of overhanging end of front arm; 1112. front pin mounting hole; 112. front of high speed end of arm carrier; 1123. rear pin mounting hole; 113. rear of high speed end of arm carrier; 1133. input end gear mounting hole; 114. connecting arm; 1141. side near high speed end of arm carrier; 1142. side near low speed end of arm carrier; 1144. cylinder receiving cavity; 12. cutting transmission mechanism; 13. drum; 14. bearing; 15. mandrel;

[0037] 2. machine body; 21. front body section housing; 211. first ear seat; 212. second ear seat; 213. connecting base; 2131. pin hole; 214. front recess; 215. larger diameter slot; 216. smaller diameter slot; 22. rear body section housing; 221. coal flow rear passage; 2211. slot floor; 23. pin;

[0038] 3. cutting motor;

[0039] 4. height adjustment cylinder; 41. outer pin;

[0040] 5. support shoe;

[0041] 9. conveyor; 91. blade; 95. conveying trough. DETAILED DESCRIPTION

[0042] A thin seam short span coal mining machine (may be referred to as a coal mining machine) is disclosed, such as Figures 1-8As shown, it comprises a front body part shell 21 and two swing arms 1 respectively hinged at the left and right ends of the front body part shell, the shell of the swing arm is a swing arm shell 11, and each swing arm shell 11 is hinged with the front body part shell by a cutting motor 3 as a hinge pin shaft, and the cutting motor is fixed relative to the front body part shell. The main body of the swing arm shell is an arm support extending left and right, and a cutting transmission mechanism 12 is installed in the arm support. The cutting transmission mechanism adopts a fixed shaft gear transmission mechanism. In order to distinguish the two ends of the arm support, the input end gear (also the high-speed end gear) and the output end gear (also the low-speed end gear) of the cutting transmission mechanism are respectively taken as the high-speed end and the low-speed end of the arm support. A connecting arm 114 is provided in the middle of the arm support and suspends forward from the arm support, and a front arm 111 is provided on the connecting arm and suspends left or right from the connecting arm, that is, for the right swing arm shell of the coal mining machine, the front arm suspends left from the connecting arm; for the left swing arm shell of the coal mining machine, the front arm suspends right from the connecting arm. The front arm 111 and the front part 112 of the high-speed end of the arm support are respectively provided with a front pin shaft mounting hole 1112 and a rear pin shaft mounting hole 1123, the input end gear is mounted in the input end gear mounting hole 1133 of the rear part 113 of the high-speed end of the arm support, and the front pin shaft mounting hole and the rear pin shaft mounting hole are coaxial with the input end gear. The cutting motor 3 is mounted in the front and rear pin shaft mounting holes, and the output shaft of the cutting motor is coaxially connected with the input end gear of the corresponding side. The coaxial front and rear pin shaft mounting holes and the input end gear can ensure that the cutting motor is coaxial with the input end gear after installation to transmit power. By taking the cutting motor as a whole as a pin shaft, the left and right lengths of the front body part shell are shortened, which is equivalent to shortening the left and right lengths of the suspension body section of the coal mining machine, and the structure of the cutting mechanism is simplified. The layout of the winding and rotor and other related structures in the cutting motor can still adopt conventional structures.

[0043] The lower part of the connecting arm is provided with an oil cylinder accommodating cavity 1144 extending left and right and opening downward, and the oil cylinder accommodating cavity is located below the front arm in the front-rear direction. A height-adjusting oil cylinder 4 is installed in the oil cylinder accommodating cavity, one end of the height-adjusting oil cylinder is hinged to the connecting arm, and the other end is hinged to the front body part shell, and the two hinged axes are both front-rear extending. The extension and contraction of the height-adjusting oil cylinder can drive the swing arm shell to swing up and down around the front body part shell. The oil cylinder accommodating cavity provides a relatively clean working space for the height-adjusting oil cylinder, ensures that the swing arm shell is not affected by coal and other mining materials during swinging, and finally ensures that the maximum mining range is not affected.

[0044] A pair of coaxial oil cylinder outer pin holes are provided on the front and rear cavity walls of the oil cylinder accommodating cavity, the axes of the oil cylinder outer pin holes extend front-rear and are close to the low-speed end of the arm support in the left-right direction. The oil cylinder outer pin holes are used to install an outer pin shaft 41, and the outer pin shaft is used to install a hinged lug of one end of the height-adjusting oil cylinder.

[0045] The left and right width of the middle and upper part of the connecting arm in the height direction is the narrowest, and the left and right width becomes wider as it approaches the upper and lower ends, forming a flat and thin structure, especially the lower part is wider, which is used to set the oil cylinder accommodating cavity. The whole connecting arm forms a flat and thin structure. The left and right width of the narrowest part is preferably the same height as the front pin shaft mounting hole. The top surface of the connecting arm is inclined, and the top surface of the connecting arm in the left and right direction is higher as it approaches the high-speed end of the same side arm frame. The flat and thin structure of the connecting arm and the special inclined surface structure make the swing arm shell have little effect on the upper coal table when it swings up and down, so that a large mining range can be ensured.

[0046] A set of bearings 14 is installed in each front pin shaft mounting hole and rear pin shaft mounting hole, and the housing of each cutting motor is rotatably supported in the same side front pin shaft mounting hole and rear pin shaft mounting hole through the bearings. The load at the hinge is mostly borne by the bearings, which can well protect the swing arm shell, the machine body shell and the cutting motor from being affected or less affected, and maintain the connection reliability.

[0047] The bearings preferably adopt knuckle bearings, which have large load capacity, impact resistance, corrosion resistance, wear resistance and self-aligning. The use of knuckle bearings helps to maintain the concentricity between the front and rear pin shaft mounting holes and the housing of the cutting motor. A wear-reducing layer is provided between the inner ring and the outer ring of the knuckle bearing to reduce the wear of the sliding pair of the bearing. A sealing seat is respectively provided on the radially outer side of the inner ring and the front and rear ends of the outer ring, and a sealing groove is provided on the radially inner hole surface and the outer end surface of the sealing seat, and a sealing ring is installed in the sealing groove. By providing dust separation structures at both ends, the cleanliness of the internal friction pair can be ensured. The use of the knuckle bearing can improve the service life of the sliding pair and also help to improve the transmission accuracy between the cutting motor and the cutting transmission mechanism.

[0048] The left and right ends of the front main part shell are respectively provided with a first ear seat 211, a second ear seat 212 and a connecting base 213 from front to back, a front groove 214 is formed between the first ear seat and the second ear seat, and a rear groove is formed between the second ear seat and the connecting base, and the high-speed end of the front arm and the arm frame on the same swing arm shell are respectively inserted into the front groove and the rear groove located on the same side. Each cutting motor is installed in the inner hole formed by the ear hole of the left and right same side first ear seat, the front pin shaft mounting hole, the ear hole of the second ear seat and the rear pin shaft mounting hole. By taking the cutting motor as a whole pin shaft, the left and right lengths of the front main part shell are shortened, which is equivalent to shortening the left and right lengths of the coal mining machine suspension body section, and simplifying the structure of the cutting mechanism. The layout of the winding and rotor and other related structures inside the cutting motor can still use conventional structures.

[0049] The rear groove is a stepped groove, wherein the larger diameter groove 215 is used to accommodate the front part of the high-speed end of the arm frame, and the smaller diameter groove 216 is used to accommodate the rear part of the high-speed end of the arm frame. Correspondingly, the outer surface of the high-speed end of the arm frame is also provided in a stepped shape.

[0050] The overhanging end outer surface 1111 of the front arm and the high speed end outer surface of the arm support on the same swing arm housing are provided as a first set of convex circular cylindrical surfaces coaxial with the front pin shaft mounting hole, the front and rear grooves on the same side are provided as a first set of concave circular cylindrical surfaces coaxial with the front pin shaft mounting hole, and the first set of concave circular cylindrical surfaces are coaxial with the first set of convex circular cylindrical surfaces and are spaced apart from each other. The side surface 1141 of the connecting arm near the high speed end of the arm support is provided as a second set of concave circular cylindrical surfaces coaxial with the front pin shaft mounting hole, and the overhanging end outer surfaces of the first and second ear seats 211 and 212 on the same side are provided as a second set of convex circular cylindrical surfaces coaxial with the front pin shaft mounting hole, and the second set of convex circular cylindrical surfaces are coaxial with the second set of concave circular cylindrical surfaces and are spaced apart from each other. By controlling the size of the corresponding spacing within a suitable range, the accumulation of coal and rock into the swing arm housing and the front main body housing during the swing of the swing arm housing relative to the front main body housing can be effectively controlled.

[0051] The thin coal seam short span mining machine further comprises a clutch mechanism, the clutch mechanism comprises a mandrel 15 and a clutch device, and the clutch device is connected in front of the mandrel. The front part of the mandrel is provided with a front spline shaft section, the rear part of the mandrel is provided with a rear spline shaft section and a guide shaft section, and the spline shaft section is located in front of the guide shaft section. The core of the input end gear is provided with a gear spline hole and a guide hole in front and back. The front part of the output shaft of the cutting motor is provided with a motor spline hole. When the clutch device is located at the rear limit position (i.e. the "engaged" position), the front spline shaft section and the rear spline shaft section of the mandrel are respectively spline-coupled with the motor spline hole and the gear spline hole, and the front part of the guide shaft section is located in the guide hole, and a radial gap is left between the guide shaft section and the guide hole. When the clutch device is pulled forward, the rear spline shaft section of the mandrel is disengaged from the gear spline hole, the rear part of the guide shaft section is located in the guide hole, and the front spline shaft section of the mandrel is partially disengaged from the motor spline hole. A radial gap is left between the guide shaft section and the guide hole, which increases the floating amount of the power transmission structure and improves the adaptability of the power transmission structure.

[0052] The side surface 1142 of the connecting arm near the low speed end of the arm support in the left-right direction is provided as a concave circular cylindrical surface coaxial with the output end gear. The concave circular cylindrical surface can maintain a certain gap with the blades of the drum 13, thereby improving the loading effect of the drum screw conveyor.

[0053] The middle top surface of the oil cylinder containing cavity can be a concave circular cylindrical surface extending left and right with straight generatrix, and an elastic body is embedded and installed between the middle top surface of the oil cylinder containing cavity and the cylinder barrel of the height adjustment oil cylinder. The top surface and the bottom surface of the elastic body are respectively in contact with the middle top surface of the oil cylinder containing cavity and the surface of the cylinder barrel of the height adjustment oil cylinder.

[0054] The thin seam short span coal mining machine further comprises a rear main body part shell 22, and the front main body part shell is fixedly connected to the front side of the rear main body part shell in the middle left and right. A plurality of pin shaft holes 2131 are arranged on the rear end face of the front main body part shell, and the front and rear main body part shells are positioned through the pin shaft 23. The front main body part shell is a multi-chamber thin-walled frame structure, and the rear main body part shell is a solid structure. The left and right ends of the rear main body part shell each extend to the rear of the low-speed end of the left and right arm supports. The front and rear main body part shells constitute the machine body 2 of the coal mining machine, the machine body is narrow in front and wide at the rear, empty in front and solid at the rear, so that the center of gravity of the machine body moves to the rear, and the stability of the whole coal mining machine is improved.

[0055] The rear main body part shell is provided with two left and right coal flow rear passages 221, which are grooves extending from front to rear and having notched bottoms facing downward. The grooves are located in the front part of the rear main body part shell, and the front ends of the grooves are open and the rear ends are closed. The left and right coal flow rear passages are respectively located between the connecting arms on the same side and the low-speed ends of the arm supports in the left and right directions. The coal flow rear passages can guide the coal flow into the conveying grooves 95 of the conveyors 9 located below the rear main body part shell, thereby improving the coal loading effect. The groove bottoms 2211 of the coal flow rear passages are divided into front and rear parts, the front part extends horizontally, and the rear part is high in front and low at the rear.

[0056] The machine body 2 is preferably a left-right symmetrical structure.

[0057] The thin seam short span coal mining machine further comprises support idlers 5, which are supported on the shovel plates 91 of the conveyors and located behind, preferably directly behind, the low-speed ends of the arm supports. The support idlers are fixedly connected to the rear main body part shell. The left and right coal flow rear passages are located inside the left and right support idlers in the left and right directions. Two inclined flow guides can be further arranged on the support idlers, which are inclined to the left rear and the right rear. The flow guides can guide the coal thrown by the drum to the left rear and the right rear of the drum, and the support idlers play a role in separating the coal flow inside and outside the drum, thereby reducing the influence of the coal flow outside the center line of the drum on the coal flow inside when the coal mining machine moves. The support idlers, the flow guides and the coal flow rear passages can facilitate the coal flow inside the drum to enter the conveying grooves, thereby improving the coal loading effect.

[0058] Unless otherwise specified, the front and rear directions mentioned herein refer to the directions close to and away from the coal wall, respectively.

Claims

1. A short-span coal mining machine for thin coal seams, characterized in that: The system includes a front main body housing and two swing arm housings hinged to the left and right ends of the front main body housing, respectively. Each swing arm housing is connected to the front main body housing by a cutting motor as a hinge pin. The cutting motor is fixed relative to the front main body housing. The main body of each swing arm housing is a boom extending left and right. A cutting transmission mechanism is installed inside the boom. The input and output gears of the cutting transmission mechanism serve as the high-speed and low-speed ends of the boom, respectively. A connecting arm extending forward from the boom is located in the middle of the boom. A forearm extending to the left or right from the connecting arm is provided on the connecting arm. The front of the high-speed end of the forearm and the boom has a front pin mounting hole and a rear pin mounting hole, respectively. The input gear is installed at the rear of the high-speed end of the boom. The mounting holes and rear pin mounting holes are coaxial with the input gear. Each front pin mounting hole and rear pin mounting hole has a set of bearings installed in it. The housing of each cutting motor is rotatably supported in the front pin mounting hole and rear pin mounting hole on the same side through the bearings. The output shaft of the cutting motor is coaxially connected to the input gear on the corresponding side. The lower part of the connecting arm is provided with a cylinder receiving cavity that extends left and right and opens downward. In the front-back direction, the cylinder receiving cavity is located below the front arm. A height adjustment cylinder is installed in the cylinder receiving cavity. One end of the height adjustment cylinder is hinged to the connecting arm, and the other end is hinged to the front main body housing. The hinge axis extends front and back. An elastic body is embedded between the top surface of the middle part of the cylinder receiving cavity and the cylinder barrel of the height adjustment cylinder.

2. The thin coal seam short span coal mining machine as described in claim 1, characterized in that: The connecting arm extends downward beyond the bottom surface of the middle part of the boom. In the height direction, the width of the connecting arm is narrowest at the upper middle part and widens towards the upper and lower ends. The top surface of the connecting arm is sloping, and in the left and right direction, the top surface of the connecting arm is higher towards the high-speed end of the boom on the same side.

3. The thin coal seam short span coal mining machine as described in claim 2, characterized in that: The bearing is a spherical plain bearing. A friction-reducing layer is provided between the inner ring and the outer ring of the spherical plain bearing. A sealing seat is provided on the radial outer side of the inner ring and at both the front and rear ends of the outer ring. A sealing groove is provided on the radial inner hole surface and the outer end face of the sealing seat, and a sealing ring is installed in the sealing groove.

4. The thin coal seam short span mining machine as described in claim 2, characterized in that: The left and right ends of the front main body housing are provided with a first ear seat, a second ear seat and a connecting base in sequence from front to back. A front groove is formed between the first ear seat and the second ear seat, and a rear groove is formed between the second ear seat and the connecting base. The forearm and the high-speed end of the boom on the same swing arm housing are respectively inserted into the front groove and the rear groove located on the same left and right sides. Each cutting motor is installed in the inner hole formed by the ear hole of the first ear seat on the same left and right sides, the front pin mounting hole, the ear hole of the second ear seat and the rear pin mounting hole.

5. The thin coal seam short span coal mining machine as described in claim 4, characterized in that: The outer surface of the cantilever end of the forearm and the outer surface of the high-speed end of the boom on the same swing arm housing are configured as a first set of convex arc cylindrical surfaces coaxial with the front pin mounting hole. The front groove and rear groove on the same left and right sides are configured as a first set of concave arc cylindrical surfaces coaxial with the front pin mounting hole. The first set of concave arc cylindrical surfaces and the first set of convex arc cylindrical surfaces are coaxial and spaced apart from each other. The side of the connecting arm near the high-speed end of the boom is configured as a second set of concave arc cylindrical surfaces coaxial with the front pin mounting hole. The outer surface of the cantilever end of the first ear and the outer surface of the cantilever end of the second ear on the same left and right sides are configured as a second set of convex arc cylindrical surfaces coaxial with the front pin mounting hole. The second set of convex arc cylindrical surfaces and the second set of concave arc cylindrical surfaces are coaxial and spaced apart from each other.

6. The thin coal seam short-span mining machine as described in claim 1, 2, 3, 4 or 5, characterized in that: It also includes a clutch mechanism, which includes a spindle and a clutch device. The clutch device is connected to the front of the spindle. The front part of the spindle is provided with a front spline shaft section, and the rear part of the spindle is provided with a rear spline shaft section and a guide shaft section. The spline shaft section is located in front of the guide shaft section. The core of the input end gear is provided with a gear spline hole and a guide hole at intervals. The front part of the output shaft of the cutting motor is provided with a motor spline hole. When the clutch device is in the rear limit position, the front spline shaft section and the rear spline shaft section of the spindle are splinedly connected to the motor spline hole and the gear spline hole, respectively. The front part of the guide shaft section is located in the guide hole, and a radial clearance is left between the guide shaft section and the guide hole.

7. The thin coal seam short-span mining machine as described in claim 1, 2, 3, 4 or 5, characterized in that: It also includes a rear main body housing, with the front main body housing fixedly connected to the front side of the rear main body housing in the center. The front main body housing is a multi-chamber thin-walled frame structure, while the rear main body housing is a solid structure. The left and right ends of the rear main body housing extend to the rear of the low-speed ends of the left and right booms, respectively.

8. The thin coal seam short span coal mining machine as described in claim 7, characterized in that: The rear main body shell is provided with two coal flow rear channels on the left and right. The coal flow rear channels are grooves that extend from front to back with the opening facing downward. The grooves are located at the front of the rear main body shell, and the front end of the grooves is open and the rear end is closed.

9. The thin coal seam short span coal mining machine as described in claim 8, characterized in that: It also includes support slippers, which are located behind the low-speed end of the boom and are fixedly connected to the rear main body shell. The left and right coal flow channels are located inside the left and right support slippers.

Images