Adjustable High-Cutting System with Internal Power

Abstract

The present invention relates to an adjustable-height cutting system with internal power, which includes a non-swing transmission part and a motorless rocker arm. The non-swing transmission part includes a stationary housing and a front-stage transmission system, and the motorless rocker arm includes a rocker arm housing and a rear-stage transmission system. A cutting motor is installed in the stationary housing, the root of the rocker arm housing is rotatably supported in the stationary housing, the output shaft of the cutting motor is connected to the rear-stage transmission system through the front-stage transmission system, a large gear coaxially connected to the input end of the rear-stage transmission system and a planetary mechanism are arranged in the root chamber of the rocker arm housing, both ends of the oil cylinder are hinged to the rocker arm housing and the stationary housing respectively, and the hydraulic system of the oil cylinder is installed in the fuel tank in the stationary housing. A transmission shaft in the front-stage transmission system replaces the pump motor of the hydraulic system to provide power for the hydraulic system. The present invention can solve the problem of the structural layout of the pump box of the hydraulic system of a low-body high-power thin coal seam shearer for coal and rock working faces with low mining height and complex geological conditions.

Description

Technical Field

[0001] The present invention relates to a cutting system for a coal shearer, in particular to a cutting system for a low-body thin coal seam shearer with a hydraulic system pump box built therein, which is applicable to working faces with low mining height and complex conditions. Background Art

[0002] For the mining of thin or extremely thin coal seams, the mining height is often low (some mining height requirements reach 0.8 m), and the geological conditions are complex, such as the coexistence of coal and rock. Therefore, in order to improve the reliability of the coal shearer, the installed power of the thin coal seam shearer is required to be larger and larger to improve its adaptability. However, as the power increases, the sizes of the motor, transmission system, etc. also increase correspondingly. When mining thin coal seams, the working face of the coal shearer is usually narrow. If the external dimensions of the coal shearer are too large, the peripheral space of the coal shearer will be compressed. For example, the clearance between machines and the coal passing height will be reduced, which will seriously affect the passing and loading of the coal shearer. Therefore, the increase in installed power makes the already difficult structural layout problem of the thin or extremely thin coal seam shearer more prominent.

[0003] The industry has proposed and gradually used a technical solution to move large and medium-sized parts such as motors and transmission gears from above the original scraper conveyor to the side close to the coal wall, that is, to adopt the way of a suspended body to solve the layout problem of large and medium-sized parts. Although this way can improve the structural layout to a certain extent, for example, it helps to increase the clearance between machines, the structural layout problem of the hydraulic system pump box still exists. The pump box provides hydraulic pressure for the swing of the rocker arm and the release of the brake, and is indispensable on the coal shearer. However, due to the existing pump box being arranged above the scraper conveyor, the pump motor has a large size, and affected by the machine surface, the total height of the hydraulic tank is relatively low, and the oil storage capacity is small. Even for the widened pump box, the oil storage capacity is still insufficient under the conditions of a large-angle working face, resulting in problems such as oil absorption. If referring to the above-mentioned way of a suspended body and arranging the pump box at the position between the left and right drums close to the coal wall, not only does the pump box itself occupy a large amount of space, but also due to the connection between the pump box and other structures, enough connection operation space needs to be reserved, so the span between the left and right drums will increase, and the connection between relevant functional systems and the adaptability of the whole machine will be greatly reduced. Summary of the Invention

[0004] The present invention aims to provide an adjustable-height cutting system with internal power, which can solve the structural layout problem of the hydraulic system pump box of a low-body high-power thin coal seam shearer for working faces with low mining height and complex geological conditions.

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

[0006] An adjustable-height cutting system with internal power, comprising a non-swing transmission part, a motorless rocker arm, a cutting motor, a hydraulic system and an oil cylinder. The non-swing transmission part includes a static housing and a front-stage transmission system arranged in the static housing. The motorless rocker arm includes a rocker arm housing and a rear-stage transmission system arranged in the rocker arm housing. The static housing is provided with a motor installation cavity and a rocker arm installation cavity. The cutting motor is fixedly installed in the motor installation cavity. The root of the rocker arm housing is rotatably supported in the rocker arm installation cavity. The output shaft of the cutting motor is connected to the rear-stage transmission system through the front-stage transmission system. The input end of the rear-stage transmission system is provided with a large gear and a planetary mechanism coaxially connected in sequence. The large gear and the planetary mechanism are arranged in the cavity at the root of the rocker arm housing. The axis of the large gear is coaxial with the rotation center of the root of the rocker arm housing. The two ends of the oil cylinder are respectively hinged to the rocker arm housing and the static housing. The axis of the large gear and the hinge axes at both ends of the oil cylinder both extend in the front-rear direction. The space behind the front-stage transmission system in the static housing is set as an oil tank. The hydraulic system is installed in the oil tank. A transmission shaft in the front-stage transmission system replaces the pump motor of the hydraulic system to provide power for the hydraulic system. The hydraulic pressure output by the hydraulic system serves as the hydraulic driving force of the oil cylinder.

[0007] The output end of the front-stage transmission system adopts a small gear and an intermediate gear set that mesh externally with each other. The intermediate gear set meshes externally with the large gear. The wheel shaft of the small gear outputs power to the hydraulic system at the same time.

[0008] The hydraulic system may include a speed increasing device, a pump set, a filtering device and pipelines. The wheel shaft of the small gear transmits power to the pump set through the speed increasing device. The oil inlet of the pump set is connected to the outlet of the filtering device through a pipeline. The oil outlet of the pump set is connected to the pressure oil port of a reversing valve group through a pipeline. The working oil port of the reversing valve group is connected to the oil inlet of the oil cylinder through a pipeline. The filtering device is fixed at the bottom of the oil tank. The pump set is fixed on the side wall of the oil tank.

[0009] The oil tank is narrow in left-right width and high in up-down height.

[0010] The speed increasing device includes a large speed increasing gear and a small speed increasing gear. The large speed increasing gear is coaxially fixed at one end of the axle of the small gear. The small speed increasing gear is coaxially fixed on the input shaft of the pump set. The small speed increasing gear is externally meshed with the large speed increasing gear. A support seat is fixed on the side wall of the fuel tank. One end of the axle of the small gear close to the pump set is supported on the support seat through a bearing. A dynamic seal matched with the shaft diameter of the axle of the small gear is also installed on the support seat. The dynamic seal separates the fuel tank from the space where the small gear and the bearing supporting the small gear are located. A positioning cover is fixed at the end of the support seat. Both ends of the axle of the small speed increasing gear are supported on the support seat and the positioning cover respectively through bearings. The pump set is fixed on the positioning cover.

[0011] The intermediate gear set includes an eccentric shaft, an eccentric sleeve, a bearing and an intermediate gear. The eccentric shaft includes reference shaft sections at both ends and an eccentric shaft section in the middle. On the surface of the eccentric shaft section, an outer eccentric groove and an inner eccentric groove extending axially and closed at both ends are respectively provided at the positions farthest and nearest to the axis of the reference shaft section. On the wall of the hole of the eccentric sleeve, a key groove extending axially and not closed at both ends is provided at the thickest part of the wall thickness. The eccentric sleeve is sleeved on the eccentric shaft section. The key groove is paired with the outer eccentric groove or the inner eccentric groove and forms a key connection with a key between the eccentric shaft and the eccentric sleeve. The reference shaft sections at both ends of the eccentric shaft are fixed on the static housing. The intermediate gear is installed on the outer cylindrical surface of the eccentric sleeve through the bearing. The intermediate gear is located between the small gear and the large gear and is externally meshed with them respectively. The axes of the small gear, the intermediate gear and the large gear are located in the same plane. The eccentric shaft has two optional installation positions, which are the positions where the outer eccentric groove and the inner eccentric groove are closest to the axis of the large gear.

[0012] A housing notch is provided on the common side wall between the rocker arm installation cavity and other adjacent cavities on the static housing. A rocker arm housing notch is provided on the root side wall of the rocker arm housing. In the installed state, the rocker arm housing notch always has a partially overlapping area with the housing notch in the circumferential direction. The intermediate gear set and the large gear remain meshed in the overlapping area of the housing notch and the rocker arm housing notch.

[0013] A bearing seat is also fixed on the inner wall of the cavity at the root of the rocker arm housing near the large gear. The input shaft diameter of the large gear is supported on the inner wall of the bearing seat through a bearing. A bearing seat notch is provided on the side wall of the bearing seat. The circumferential position and size of the bearing seat notch are preferably consistent with those of the rocker arm housing notch.

[0014] A guard plate can also be installed on the static housing. The static housing, the rocker arm housing and the guard plate together enclose a closed cavity. The oil cylinder is located in the closed cavity.

[0015] The adjustable-height cutting system with internal power may also be provided with a tubular sealing cylinder. The sealing cylinder penetrates through the fuel tank in the front-back direction and is fixed on the stationary housing. The front end opening of the sealing cylinder is covered by a cover plate, and the cover plate is fixed on the outer side surface of the coal wall side of the stationary housing. The rear end of the sealing cylinder extends to the front end of the cylinder pin at the hinge joint of the oil cylinder and the stationary housing and faces the cylinder pin. The aperture of the sealing cylinder is larger than the diameter of the cylinder pin, and a static seal is provided between the outer wall of the sealing cylinder and the side wall of the fuel tank.

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

[0017] The present invention leads out a branch from the non-swing transmission part to replace the pump motor to provide power for the pump unit of the hydraulic system. Since the power of the cutting motor is much larger than that of the pump motor, even if the power demand of the hydraulic system is large, it does not need to occupy a larger installation space like a traditional pump unit due to the need to equip a pump motor with a larger power. Therefore, the hydraulic system has a compact structure and surplus power at the same time.

[0018] The present invention makes full use of the idle space in the stationary housing of the non-swing transmission part and uses it as the fuel tank of the hydraulic system to install the hydraulic system, making the structure of the shearer more compact, neither increasing the machine surface height nor increasing the span of the drum.

[0019] The size of the fuel tank is preferably set to be narrow in the left-right width and high in the up-down height. In this way, the oil level in the fuel tank is hardly affected by the changes in the working face inclination (left-right) and the dip mining angle (front-back).

[0020] The present invention adopts a brand-new structural arrangement method, including setting a swing transmission part and a non-swing transmission part, allowing the swing transmission part to swing around a fixed axis relative to the non-swing transmission part, and placing large and medium-sized parts such as the cutting motor, planetary mechanism, and large gear in the housing of the non-swing transmission part. When the swing transmission part rotates, the positions of the large and medium-sized parts remain unchanged. Therefore, when the front drum's bottom cutter cuts out the passage for the suspended fuselage and the rear drum's top cutter cuts off the remaining coal platform, they will not be affected by the large and medium-sized parts. Therefore, the rocker arm housing will not interfere with the coal platform, realizing the suspended fuselage arrangement method, reducing the height of the shearer body, and ensuring the required cutting height range.

[0021] Due to the adoption of the gear speed change mechanism with the eccentric shaft and eccentric sleeve as the core, by changing the installation directions of the eccentric shaft and the eccentric sleeve and replacing the large gear and small gear of different sizes, a wide range of speed changes can be achieved. By matching different specifications of drums, more choices can be made for parameters such as cutting force and cutting linear speed, so as to adapt to the mining of various materials with different hardnesses such as coal and rock.

[0022] The present invention uses the stationary housing, the rocker arm housing, and the guard plate to jointly enclose a closed cavity, providing a good external working environment for the oil cylinder, avoiding the adverse effects of pulverized coal and gangue on the oil cylinder, making the telescopic movement of the oil cylinder more reliable and having a longer service life, thereby providing a more reliable and high-quality support for the rotation of the rocker arm relative to the non-swing transmission part. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is the front view of the left cutting system of the present invention;

[0024] Figure 2 is the sectional view of the left cutting system of the present invention;

[0025] Figure 3 is Figure 2 the enlarged view of the structural layout of the hydraulic system in

[0026] Figure 4 is Figure 2 the schematic diagram of the power part of the hydraulic system in

[0027] Figure 5 is the sectional view of the motorless rocker arm of the left cutting system of the present invention;

[0028] Figure 6 is the partial sectional view of the notch of the rocker arm housing and the notch of the bearing seat;

[0029] Figure 7 is the sectional view of a part of the structure of the non-swing transmission part of the left cutting system of the present invention;

[0030] Figure 8 is the schematic diagram of the structure of the intermediate gear set;

[0031] Figure 9 is Figure 8 the schematic diagram of the structure of the eccentric shaft in

[0032] Figure 10 is Figure 8 the schematic diagram of the structure of the eccentric sleeve in

[0033] Figure 11 is the schematic diagram of the structure of the large reduction ratio gear speed change mechanism of the present invention;

[0034] Figure 12 is the schematic diagram of the structure of the medium reduction ratio gear speed change mechanism of the present invention;

[0035] Figure 13 is the schematic diagram of the structure of the small reduction ratio gear speed change mechanism of the present invention;

[0036] Figure 14 is the schematic diagram of the installation structure of the sealing cylinder of the present invention;

[0037] Figure 15 This is a schematic structural diagram of two sets of cutting systems on the left and right sides of the double-drum shearer for the present invention;

[0038] Figure 16 This is a sectional view of two sets of cutting systems on the left and right sides of the double-drum shearer for the present invention.

[0039] Reference numerals:

[0040] 1. Non-swing transmission part; 11. Static housing; 111. Housing notch; 112. Front positioning hole; 113. Rear positioning hole; 114. Rocker arm mounting cavity; 115. Cylinder seat; 116. Closed cavity; 119. Fuel tank; 1191. Fuel tank opening; 12 (and 12', 12"). Pinion gear; 13. Intermediate gear set; 131. Eccentric shaft; 1311. Reference shaft section; 1312. Eccentric shaft section; 1313. Outer eccentric groove; 1314. Inner eccentric groove; 1315. Keyway; 132. Eccentric sleeve; 1323. Keyway; 133. Bearing; 134. Intermediate gear; 14. Guard plate;

[0041] 2. Motorless rocker arm; 20 Support positioning bearing; 21. Rocker arm housing; 211. Rocker arm housing notch; 22 (and 22', 22"). Large gear; 23. Planetary mechanism; 24. Fixed-axis gear transmission structure; 25. Drum; 26. Bearing seat; 261. Bearing seat notch; 27. Cylinder seat;

[0042] 3. Cylinder; 31. Cylinder connection ear; 32. Cylinder pin; 33. Sealing cylinder; 34. Static seal;

[0043] 4. Hydraulic system; 41. Speed increasing device; 411. Speed increasing large gear; 412. Speed increasing small gear; 413. Dynamic seal; 414. Support seat; 415. Positioning pin; 416. Positioning cover; 42. Pump group; 43. Filter device; 45. Pipeline. Detailed implementation manners

[0044] The present invention discloses a height-adjustable cutting system with internal power, as Figure 1-16 shown, which includes a non-swing transmission part 1, a motorless rocker arm 2, a cutting motor, a hydraulic system 4 and a cylinder 3. The non-swing transmission part includes a static housing 11 and a front-stage transmission system arranged in the static housing. The motorless rocker arm is equivalent to a swing transmission part and includes a rocker arm housing 21 and a rear-stage transmission system arranged in the rocker arm housing. The static housing is provided with a motor mounting cavity and a rocker arm mounting cavity 114. The cutting motor is fixedly installed in the motor mounting cavity. The root of the cylindrical structure of the rocker arm housing is rotatably supported in the rocker arm mounting cavity, so that the rocker arm housing can perform fixed-axis swinging relative to the static housing, wherein the root of the rocker arm housing only "rotates on its own" in the static housing.

[0045] The output shaft of the cutting motor is connected to the rear-stage transmission system through the front-stage transmission system, that is, the power output by the cutting motor is transmitted through the front-stage transmission system and the rear-stage transmission system in sequence, and finally transmitted to the drum 25 at the other end of the rocker arm housing. The input end of the rear-stage transmission system is provided with a large gear 22 and a planetary mechanism 23 connected coaxially in sequence. The large gear and the planetary mechanism are arranged in the chamber at the root of the rocker arm housing. The axis of the large gear is coaxial with the rotation center at the root of the rocker arm housing. When the rocker arm makes a fixed-axis swing, the large gear 22 and the planetary mechanism 23, as large and medium-sized parts in the rear-stage transmission system, always rotate in place in the stationary housing. The cutting motor, as another large and medium-sized component, will not change its position with the swing of the rocker arm because it is installed in the stationary housing. In particular, there is no height change. Therefore, a large space can be maintained between the rocker arm housing and the upper coal platform. Therefore, even when the rear rocker arm cuts the top coal, the rocker arm housing will not interfere with the coal platform, etc. Therefore, the present invention can ensure that the theoretical cutting height range does not shrink while solving the problem of the layout of large and medium-sized parts. In addition, the above-mentioned large and medium-sized parts are closer to the coal wall side than the small and medium-sized parts of the cutting system, which is beneficial to reducing the machine surface height of the shearer.

[0046] Both ends of the oil cylinder are respectively hinged to the rocker arm housing and the stationary housing. The axis of the large gear and the hinge axes at both ends of the oil cylinder all extend in the front-rear direction. The front and rear directions of the shearer are the directions pointing from the inside of the shearer to the coal wall side and the goaf side of the shearer respectively. When the oil cylinder expands and contracts, it drives the rocker arm to rotate and swing relative to the non-swinging transmission part.

[0047] The space behind the front-stage transmission system in the stationary housing is set as an oil tank 119. The hydraulic system 4 is installed in the oil tank. A transmission shaft in the front-stage transmission system replaces the pump motor of the hydraulic system to provide power for the hydraulic system, that is, the pump unit is a pump unit without a pump motor. The hydraulic pressure output by the hydraulic system serves as the hydraulic driving force of the oil cylinder.

[0048] Since the power of the cutting motor is much greater than that of the pump motor, no matter how large the power requirement of the hydraulic system is, it does not need to occupy a larger installation space like a traditional pump unit due to the need to equip a pump motor with a larger power. Therefore, the hydraulic system is structurally compact and has surplus power at the same time. The motor installation cavity and the rocker arm installation cavity are usually arranged at the left and right ends of the stationary housing. Most of the space between these two cavities is an idle area. Utilize a part of the idle area to make an internal oil tank, and change the oil tank of the hydraulic system from an external one to an internal one in the cutting system, which can make the structure of the shearer more compact, neither increasing the machine surface height nor increasing the span of the drum.

[0049] AsFigure 2 As shown, in the installed state, the opening of the rocker arm mounting cavity faces backward. The root cylinder structure of the rocker arm housing is inserted into the rocker arm mounting cavity from back to front and is rotatably supported on the inner wall of the rocker arm mounting cavity by two support positioning bearings 20 at the front and back. In this embodiment, the front and rear sections of the inner wall of the rocker arm mounting cavity 114 are respectively a front positioning hole 112 and a rear positioning hole 113, which are respectively used for installing the two support positioning bearings 20 at the front and back.

[0050] The rocker arm housing further includes a head and a neck located between the head and the root. The rocker arm housing presents a concave-shaped structure in which both the head and the root protrude forward relative to the neck. The large gear 22, the planetary mechanism 23, and the medium and small-sized fixed-axis gear transmission structure 24 form the rear-stage transmission system. The fixed-axis gear transmission structure 24 is located in the chambers of the neck and the head. The drum 25 is installed on the head of the rocker arm housing and rotates relative to the rocker arm housing.

[0051] The output end of the front-stage transmission system can adopt a small gear 12 and an intermediate gear set 13 that are externally meshed with each other. The intermediate gear set is externally meshed with the large gear. The axle of the small gear outputs power to the hydraulic system at the same time.

[0052] In this embodiment, as Figure 3 shown, the hydraulic system includes a speed increasing device 41, a pump set 42, a filtering device 43, and a pipeline 45. The axle of the small gear transmits power to the pump set through the speed increasing device. The oil inlet of the pump set is connected to the outlet of the filtering device through a pipeline. The oil outlet of the pump set is connected to the pressure oil port of the reversing valve group through a pipeline. The working oil port of the reversing valve group is connected to the oil inlet of the oil cylinder through a pipeline. The filtering device is fixed at the bottom of the fuel tank. The pump set is fixed on the side wall of the fuel tank. The reversing valve group is arranged outside the fuel tank and can even be arranged outside the cutting system. The speed increasing device increases the rotational speed of the power transmitted by the small gear and then drives the pump set 42 to ensure that the hydraulic system has sufficient flow and pressure. The filtering device is used to purify the oil fluid before the pump set.

[0053] The size of the fuel tank is preferably set to be narrow in the left-right width and high in the up-down height. In this way, the oil level in the fuel tank is hardly affected by the changes in the working face inclination (left-right) and the dip mining angle (front-back).

[0054] As Figure 4As shown, the speed increasing device includes a large speed increasing gear 411 and a small speed increasing gear 412. The large speed increasing gear is coaxially fixed to one end of the axle of the small gear, and the small speed increasing gear is coaxially fixed to the input shaft of the pump set. The small speed increasing gear is externally meshed with the large speed increasing gear. A support seat 414 is fixed on the side wall of the fuel tank. One end of the axle of the small gear close to the pump set is supported on the support seat by a bearing. A dynamic seal 413 matching the shaft diameter of the axle of the small gear is also installed on the support seat. The dynamic seal separates the fuel tank from the space where the small gear and the bearing supporting the small gear are located. A positioning cover 416 is fixed at the end of the support seat, and the two can be positioned by a positioning pin 415. The two ends of the axle of the small speed increasing gear are respectively supported on the support seat and the positioning cover by bearings. The pump set is fixed on the positioning cover. An opening 1191 of the fuel tank can be provided on the top plate of the fuel tank to facilitate the installation of the hydraulic system.

[0055] In this embodiment, the intermediate gear set preferably includes an eccentric shaft 131, an eccentric sleeve 132, a bearing 133, and an intermediate gear 134. The eccentric shaft includes a reference shaft section 1311 at both ends and an eccentric shaft section 1312 in the middle. On the surface of the eccentric shaft section, an outer eccentric groove 1313 and an inner eccentric groove 1314 that extend axially and are closed at both ends are respectively provided at the positions farthest and closest to the axis of the reference shaft section. On the wall of the hole of the eccentric sleeve, a key groove 1323 that extends axially and is not closed at both ends is provided at the thickest part of the wall thickness. The eccentric sleeve is sleeved on the eccentric shaft section. The key groove 1323 is paired with the outer eccentric groove or the inner eccentric groove and forms a key connection between the eccentric shaft and the eccentric sleeve with a key. The reference shaft sections at both ends of the eccentric shaft are fixed on the stationary housing. The intermediate gear 134 is installed on the outer cylindrical surface of the eccentric sleeve through the bearing 133. The intermediate gear is located between the small gear 12 and the large gear 22 and is externally meshed with them respectively. The axes of the small gear, the intermediate gear, and the large gear are located in the same plane. The small gear, the intermediate gear set, and the large gear form a gear speed change mechanism.

[0056] The eccentric shaft has two optional mounting positions relative to the stationary housing, which are the positions where the outer eccentric groove and the inner eccentric groove are closest to the axis of the large gear. The eccentric sleeve also has two optional mounting positions relative to the eccentric shaft section, which are the positions where the outer eccentric groove and the inner eccentric groove on the eccentric shaft section are paired with the key groove 1323 on the eccentric sleeve and key-connected with the key. When the eccentric shaft and the eccentric sleeve are arranged and installed according to their respective two optional mounting positions, with the mounting position of the reference shaft section of the eccentric shaft fixed, the axis of the outer cylindrical surface of the eccentric sleeve can have 3 to 4 positions, that is, the axis of the intermediate gear 134 can have 3 to 4 possible positions. In other words, the distances between the intermediate gear and the axes of the large gear and the small gear can have 3 to 4 possible variations. By simply replacing the large gears 22, 22' or 22" of different sizes and the small gears 12, 12' or 12" of different sizes to adapt to such changes in the distance, different reduction ratios can be achieved, so as to obtain a wide range of rotational speeds at the drum and achieve the purpose of speed change.

[0057] By adopting the above gear speed change mechanism, different rotational speed outputs of the end drum 25 can be realized, so that different output cutting parameters, such as cutting force and cutting line speed, etc., can be obtained. After configuring drums of different diameters, the mining of different hardness materials such as coal and rock can be realized.

[0058] Key grooves 1315 can be provided on at least one outer end surface of the reference shaft section. The key grooves 1315 cooperate with keys to be used for positioning and anti-rotation of the eccentric shaft. The extending direction of the key grooves is preferably perpendicular to the plane where the axes of the small gear, the intermediate gear and the large gear are located, which is the vertical direction in this embodiment.

[0059] A housing notch 111 is provided on the common side wall between the rocker arm mounting cavity on the stationary housing and other adjacent cavities (mainly referring to the cavity where the output end of the front-stage transmission system is located) to provide space for the rotation of the intermediate gear. A rocker arm housing notch 211 is correspondingly provided on the root side wall of the rocker arm housing. In the installed state, the rocker arm housing notch 211 always has a partially overlapping area with the housing notch 111 in the circumferential direction, and this overlapping area should be large enough to ensure that the intermediate gear set and the large gear remain meshed in the overlapping area of the housing notch and the rocker arm housing notch.

[0060] In this embodiment, a bearing seat 26 is also fixed on the inner wall of the cavity at the root of the rocker arm housing 21 near the large gear. The input shaft diameter of the large gear is supported on the inner wall of the bearing seat 26 through a bearing. In this case, a bearing seat notch 261 is also provided on the side wall of the bearing seat. See Figure 6, the circumferential position and size of the bearing seat notch 261 are preferably the same as those of the rocker arm housing notch 211. The rocker arm housing notch 211 and the bearing seat notch 261 together provide sufficient space for the intermediate gear 134 and the large gear 22.

[0061] Except for the parts mentioned above, the existing transmission structures can be adopted in the front-stage transmission system and the rear-stage transmission system, such as gear transmission, spline transmission, etc.

[0062] A guard plate 14 can also be installed on the stationary housing. The stationary housing, the rocker arm housing and the guard plate together enclose a closed cavity 116. The oil cylinder seat 115 provided on the stationary housing is located in the closed cavity, and the oil cylinder seat 27 provided on the outer side of the root of the rocker arm housing is also located in the closed cavity. In the installed state, during the swinging process of the rocker arm without a motor, the whole oil cylinder is always in the closed cavity. The closed cavity provides a good external environment for the oil cylinder. For example, it can avoid the influence of coal powder and gangue on the oil cylinder, make the telescopic of the oil cylinder more reliable and have a longer service life, thus providing a more reliable and high-quality support for the rotation of the rocker arm relative to the non-swinging transmission part.

[0063] As Figure 14 shown, the height-adjustable cutting system with internal power can also be provided with a thin-walled tubular sealing cylinder 33. The sealing cylinder penetrates through the fuel tank in the front-back direction and is fixed on the stationary housing. The front end opening of the sealing cylinder is covered by a cover plate, and the cover plate is fixed on the outer side surface of the coal wall side of the stationary housing. The rear end of the sealing cylinder extends to the front end of the oil cylinder pin 32 at the hinge joint of the oil cylinder and the stationary housing and faces the oil cylinder pin. The aperture of the sealing cylinder is larger than the diameter of the oil cylinder pin. A static seal 34 is provided between the outer wall of the sealing cylinder and the side wall of the fuel tank. The oil cylinder connecting ear 31 is hinged to the oil cylinder seat 115 on the stationary housing through the oil cylinder pin 32. When the oil cylinder needs to be disassembled, the cover plate can be removed and the operation can be carried out on the opening side of the sealing cylinder on the coal wall side, and the oil cylinder pin can be removed by using a pull rod. The advantages of setting the sealing cylinder are as follows: on the one hand, it provides two possibilities and operation spaces for disassembling the oil cylinder pin 32 from the front and rear ends. When disassembling from the front end, the workload of supporting disassembly is less, which is beneficial to the maintenance convenience under the conditions of extremely thin or thin coal seams; on the other hand, since the sealing cylinder is a thin-walled and small-diameter cylindrical structure, compared with the way of directly casting a thick-walled stationary housing and then machining a deep hole on the side wall, the space occupied by the fuel tank is smaller, which is beneficial to ensuring that the hydraulic system has enough oil storage volume.

Claims

1. An adjustable-height cutting system with internal power, characterized in that: It includes a non-swing transmission part, a motorless rocker arm, a cutting motor, a hydraulic system and an oil cylinder. The non-swing transmission part includes a stationary housing and a front-stage transmission system arranged in the stationary housing. The motorless rocker arm includes a rocker arm housing and a rear-stage transmission system arranged in the rocker arm housing. An electric motor mounting cavity and a rocker arm mounting cavity are provided in the stationary housing. The cutting motor is fixedly installed in the electric motor mounting cavity. The root of the rocker arm housing is rotatably supported in the rocker arm mounting cavity. The output shaft of the cutting motor is connected to the rear-stage transmission system through the front-stage transmission system. A large gear and a planetary mechanism are coaxially connected in sequence at the input end of the rear-stage transmission system. The large gear and the planetary mechanism are arranged in the cavity at the root of the rocker arm housing. The axis of the large gear is coaxial with the rotation center of the root of the rocker arm housing. The two ends of the oil cylinder are respectively hinged to the rocker arm housing and the stationary housing. The axis of the large gear and the hinge axes at both ends of the oil cylinder both extend in the front-rear direction. The rocker arm housing further includes a head and a neck located between the head and the root. The rocker arm housing presents a concave-shaped structure with both the head and the root protruding forward relative to the neck. The large gear, the planetary mechanism and a fixed-axis gear transmission structure form the rear-stage transmission system. The fixed-axis gear transmission structure is located in the cavities of the neck and the head. The rear space of the front-stage transmission system in the stationary housing is set as an oil tank. The hydraulic system is installed in the oil tank. A transmission shaft in the front-stage transmission system replaces the pump motor of the hydraulic system to provide power for the hydraulic system. The hydraulic pressure output by the hydraulic system serves as the hydraulic driving force of the oil cylinder.

2. The adjustable-height cutting system with internal power according to claim 1, characterized in that: The output end of the front-stage transmission system adopts a small gear and an intermediate gear set that mesh externally with each other. The intermediate gear set meshes externally with the large gear. The axle of the small gear outputs power to the hydraulic system at the same time.

3. The adjustable-height cutting system with internal power according to claim 2, characterized in that: The hydraulic system includes a speed increasing device, a pump set, a filtering device and pipelines. The axle of the small gear transmits power to the pump set through the speed increasing device. The oil inlet of the pump set is connected to the outlet of the filtering device through a pipeline. The oil outlet of the pump set is connected to the pressure oil port of a reversing valve group through a pipeline. The working oil port of the reversing valve group is connected to the oil inlet of the oil cylinder through a pipeline. The filtering device is fixed at the bottom of the oil tank. The pump set is fixed on the side wall of the oil tank.

4. The adjustable-height cutting system with internal power according to claim 3, characterized in that: The oil tank is narrow in left-right width and high in up-down height.

5. The adjustable-height cutting system with internal power according to claim 4, characterized in that: The speed increasing device includes a large speed increasing gear and a small speed increasing gear. The large speed increasing gear is coaxially fixed at one end of the axle of the small gear. The small speed increasing gear is coaxially fixed on the input shaft of the pump set. The small speed increasing gear meshes externally with the large speed increasing gear. A support seat is fixed on the side wall of the fuel tank. One end of the axle of the small gear close to the pump set is supported on the support seat by a bearing. A dynamic seal matching the shaft diameter of the axle of the small gear is also installed on the support seat. The dynamic seal separates the fuel tank from the space where the small gear and the bearing supporting the small gear are located. A positioning cover is fixed at the end of the support seat. Both ends of the axle of the small speed increasing gear are supported on the support seat and the positioning cover respectively by bearings. The pump set is fixed on the positioning cover.

6. The adjustable height cutting system with internal power as claimed in claim 5, characterized in that: The intermediate gear set includes an eccentric shaft, an eccentric sleeve, a bearing and an intermediate gear. The eccentric shaft includes reference shaft sections at both ends and an eccentric shaft section in the middle. On the surface of the eccentric shaft section, an outer eccentric groove and an inner eccentric groove extending axially and closed at both ends are respectively provided at the positions farthest and nearest to the axis of the reference shaft section. A key groove extending axially and not closed at both ends is provided at the thickest part of the wall thickness of the hole wall of the eccentric sleeve. The eccentric sleeve is sleeved on the eccentric shaft section. The key groove is paired with the outer eccentric groove or the inner eccentric groove and forms a key connection between the eccentric shaft and the eccentric sleeve with a key. The reference shaft sections at both ends of the eccentric shaft are fixed on the static housing. The intermediate gear is installed on the outer cylindrical surface of the eccentric sleeve through the bearing. The intermediate gear is located between the small gear and the large gear and meshes externally with them respectively. The axes of the small gear, the intermediate gear and the large gear are located in the same plane. The eccentric shaft has two optional installation positions, which are the positions where the outer eccentric groove and the inner eccentric groove are closest to the axis of the large gear.

7. The adjustable height cutting system with internal power as claimed in claim 6, characterized in that: A housing notch is provided on the common side wall between the rocker arm installation cavity and other adjacent cavities on the static housing. A rocker arm housing notch is provided on the root side wall of the rocker arm housing. In the installed state, the rocker arm housing notch always has a partially overlapping area with the housing notch in the circumferential direction. The intermediate gear set and the large gear remain meshed in the overlapping area of the housing notch and the rocker arm housing notch.

8. The adjustable height cutting system with internal power as claimed in claim 7, characterized in that: A bearing seat is also fixed on the inner wall of the cavity at the root of the rocker arm housing near the large gear. The input shaft diameter of the large gear is supported on the inner wall of the bearing seat by a bearing. A bearing seat notch is provided on the side wall of the bearing seat. The circumferential position and size of the bearing seat notch are consistent with those of the rocker arm housing notch.

9. The adjustable height cutting system with internal power as claimed in claim 1, 2, 3, 4, 5, 6, 7 or 8, characterized in that: A guard plate is installed on the stationary housing. The stationary housing, the rocker arm housing and the guard plate jointly enclose a closed cavity, and the oil cylinder is located in the closed cavity.

10. The adjustable height cutting system with internal power according to claim 1, 2, 3, 4, 5, 6, 7 or 8, characterized in that: a tubular sealing cylinder is further provided. The sealing cylinder penetrates through the fuel tank in the front-rear direction and is fixed on the stationary housing. The front end opening of the sealing cylinder is covered by a cover plate, and the cover plate is fixed on the outer side surface of the coal wall side of the stationary housing. The rear end of the sealing cylinder extends to the front end of the oil cylinder pin at the hinge joint of the oil cylinder and the stationary housing and faces the oil cylinder pin. The aperture of the sealing cylinder is larger than the diameter of the oil cylinder pin, and a static seal is provided between the outer wall of the sealing cylinder and the side wall of the fuel tank.

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