High-load shearer travel system

Abstract

The present invention relates to a high-load walking system for a shearer, which includes a guiding sliding shoe and a walking wheel and a pin rail that mesh with each other. The walking wheel is provided with double-row teeth, and the structural parameters of the double-row teeth are the same. The pin rail is provided with double-row tooth grooves, and the structural parameters of the double-row tooth grooves are the same. The teeth and the tooth grooves are meshed correspondingly row by row. The tooth surface of the teeth is a convex surface in the tooth width direction. Correspondingly, the groove wall of the tooth groove is a concave surface in the tooth width direction. The walking wheel and the pin rail are in a state of mutual convex-concave fitting in the normal section at each meshing position of the tooth profile curve of any tooth. The present invention has a large load-bearing capacity, high reliability, can adapt to the horizontal bending of the pin rail, and no stress concentration will occur at the edge of the walking wheel gear, and it can better meet the needs of the development of shearers towards large mining heights and high powers.

Description

Technical Field

[0001] The invention relates to a coal mining machine travel system with a relatively high load-bearing capacity, belonging to the technical field of coal mining equipment. Background Art

[0002] The driving force for the shearer to travel on the coal mining face of the coal mine is usually ultimately driven by the meshing transmission of the shearer travel wheel and the pin row series of the scraper. The scraper pin row series consists of multiple pin rows with the same structure. The travel wheel and the scraper pin row are open non-conjugate meshing, driving the shearer to travel back and forth. During the travel of the working face, the pin row is allowed to deflect 1° in the horizontal plane to meet the needs of the working face when the push slide is not straight and the shearer is walking in the S-bend cutting machine nest.

[0003] At present, coal mining machines are increasingly developing in the direction of large mining height and high power. The maximum installed power of coal mining machines at home and abroad has reached about 3000kW, the comprehensive mining height has reached more than 8m, and the weight of the coal mining machine has reached more than 200t. When the coal mining machine is cutting coal, the working resistance is large and the working surface has an inclination. The traction force of the coal mining machine must be increased, which makes the coal mining machine travel system face the following two key problems:

[0004] 1. How to improve the load-bearing capacity of heavy-duty large-module gears (module m>46) and pin rows and avoid stress concentration on the gear edges to increase the traction output by the coal mining machine terminal travel system and improve the reliability of the travel system?

[0005] 2. When the coal mining machine has a large traction force, the contact stress between the travel wheel and the pin row increases sharply. When the pin row is bent horizontally, how to improve the meshing stress condition between the travel wheel teeth and the pin row and improve the reliability of the travel system?

[0006] The Chinese patent application No. 200910044922.1 discloses a double-row drive chainless traction system for a coal mining machine, which utilizes multiple pin rails arranged side by side and special travel wheels (multi-row travel wheels) meshing with the multiple pin rails. The meshing of the teeth of each row of travel wheels with the corresponding pin rails is different from the meshing of the teeth of the other row of travel wheels with the corresponding pin rails by a phase angle. If the output force of each tooth is the same, the total traction force is greatly improved. If the total traction force remains unchanged, the output force of each tooth is small, thereby improving the reliability of the equipment. This application does not solve the problem of how the travel wheel adapts to the horizontal deflection angle of the pin rail, nor does it solve the problem of tooth shape. It only increases the number of pairs of travel wheel teeth meshing with the pin rails. In addition, since the tooth shape of one row of the multi-row pin rails is directly opposite to the tooth groove of another row, it is difficult to manufacture the pin row in sections. Summary of the invention

[0007] To solve the above problems, the present invention provides a high-load shearer travel system, which has a large load-bearing capacity, high reliability, can adapt to the horizontal bending of the pin rows, and the edges of the travel wheel gears will not generate stress concentration, and can better meet the needs of the development of shearers towards large mining heights and high powers.

[0008] The main technical solutions of the present invention are as follows:

[0009] A high-load shearer travel system includes a travel wheel and a pin row that mesh with each other. The travel wheel is provided with double-row teeth. The structural parameters of the double-row teeth are the same and the phases are consistent. The pin row is provided with double-row tooth grooves. The structural parameters of the double-row tooth grooves are the same and the phases are consistent. The teeth and the tooth grooves are meshed in corresponding rows. The tooth surface of the teeth is a convex surface in the tooth width direction. Correspondingly, the groove wall of the tooth groove is a concave surface in the tooth width direction. The travel wheel and the pin row are in a state of mutually concave-convex fitting on the normal section at each meshing position of the tooth profile curve of any tooth.

[0010] The travel wheel adopts a spur gear, and the single-row teeth and tooth grooves that mesh with each other are symmetric in their respective tooth width directions.

[0011] The contour of the tooth surface of the teeth on the normal section at each meshing position is in a convex shape. The contour can be a convex curve, or the middle section of the contour is a straight line and the two side sections are arcs.

[0012] When the contour is a convex curve, the curve can be an arc or a section of a curve on an ellipse.

[0013] Preferably, the curve is an arc, and the radii of the arcs corresponding to the contours of the tooth surfaces of the teeth on the normal section at each meshing position are all equal, denoted as R1. The contours of the groove walls of the tooth grooves on the normal section at each meshing position are all concave arcs, and the radii of the arcs are all equal, denoted as R2, and R1 < R2.

[0014] The ratio of R1 to R2 is preferably between 0.85 and 0.98.

[0015] A pair of tooth grooves with the same phase are connected. A step is formed between the same-side groove walls of the corresponding pair of tooth grooves at the connection.

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

[0017] By adopting a new meshing structure between the traveling wheel and the pin row, the present invention can improve the load-bearing capacity of the traveling system without changing the module of the traveling wheel, avoid the edge effect of the gear teeth, and prevent the sudden increase of the edge stress due to eccentric load on the gear teeth, thus avoiding tooth breakage or premature fatigue failure. As a result, the traction output of the shearer can continue to increase, or when the module of the traveling wheel is increased, the load-bearing capacity of the pin row can be improved. Therefore, it can not only meet the requirements of heavy load and large traction of the shearer, but also improve the reliability of the traveling system. Especially under the condition of heavy load traction of the shearer, the effect is more significant.

[0018] The present invention can well adapt to the horizontal bending of the traveling track. When the face conveyor is not straight or the face has undulations, or when the shearer pit goes in an S-shaped curve, the traveling wheel and the pin row have a tendency to automatically guide and reduce the eccentric meshing between the pin row and the traveling wheel. Therefore, it can spontaneously improve the meshing state, thereby prolonging the service life of the traveling system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of the meshing state between the traveling wheel and the pin row according to an embodiment of the present invention;

[0020] Figure 2 is Figure 1 a C-C sectional view of;

[0021] Figure 3 is a schematic diagram of the tooth structure of an embodiment of the traveling wheel;

[0022] Figure 4 is a schematic diagram of the tooth groove profile of an embodiment of the pin row;

[0023] Figure 5 is a schematic diagram of the cross-sectional view of the groove wall of a tooth groove of the pin row;

[0024] Figure 6 is a schematic diagram of the meshing force analysis between the traveling wheel and the pin row when there is an included angle between two adjacent pin rows. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The present invention discloses a high-load shearer traveling system (hereinafter referred to as the traveling system), as Figures 1-6As shown, it includes a traveling wheel 1 and a pin row 2 that mesh with each other. The pin row is fixed on the scraper along the length direction of the working surface. The traveling wheel meshes bidirectionally along the pin row to drive the coal mining machine to move back and forth along the working surface. The traveling wheel is provided with double rows of gear teeth 11 and 12. The double rows of gear teeth are machined on the same gear blank. The structural parameters of the double rows of gear teeth, such as the number of teeth, module, tooth top circle diameter, tooth profile shape, etc., are the same and the phases are consistent. The tooth surfaces on both sides of each gear tooth are convex and symmetrical in the tooth thickness direction. The pin row is provided with double rows of tooth grooves. The structural parameters of the double rows of tooth grooves are the same and the phases are consistent. The gear teeth mesh with the tooth grooves in rows. The groove walls on both sides of each tooth groove (which are also the tooth surfaces of the teeth of the pin row) are concave (for example, they can be concave arcs) and symmetrical in the tooth thickness direction of the gear teeth meshing therewith.

[0026] Through the meshing of double gear teeth, when the travel wheel meshes with the pin row and travels, the travel wheel can bear greater traction force of the coal mining machine. If an abnormal situation occurs, such as when a gear tooth breaks, there is another parallel gear tooth participating in the meshing, which can drive the coal mining machine to produce along the working face in an emergency without affecting the output. The abnormal travel wheel can be replaced during the maintenance shift, thus greatly improving the reliability of the travel system.

[0027] The center distance between the double-row gear teeth 11 and 12 along the tooth width direction is D1, which is equal to the center distance D2 between the paired tooth grooves arranged in parallel on the pin row along the tooth width direction.

[0028] The tooth surface of the gear teeth is an outward convex surface in the tooth width direction, that is, the closer to the two ends in the tooth width direction, the thinner the tooth thickness is, and the closer to the middle in the tooth width direction, the thicker the tooth thickness is. Correspondingly, the groove wall of the tooth groove is an inward concave surface in the tooth width direction, that is, the closer to the two ends in the tooth width direction, the thicker the tooth thickness is, and the closer to the middle in the tooth width direction, the thinner the tooth thickness is. The walking wheel and the pin row are in a state of mutual concave-convex engagement on the normal section of each meshing position of any gear tooth profile curve.

[0029] The gear is a spur gear. The meshing single-row gear teeth and tooth grooves are preferably symmetrical in the respective tooth width directions. In an ideal meshing state, the theoretical contact point between the gear teeth and the tooth groove is located on the symmetrical center plane of the corresponding tooth groove in the tooth width direction.

[0030] The normal section extends along the normal direction of the tooth surface at the meshing position. Each meshing position corresponds to a normal section. Taking the running wheel as an example, each point on the tooth profile curve of the gear tooth corresponds to a meshing position, which also corresponds to a normal section. The common normal line passing through the meshing position is located in the corresponding normal section, and the normal section is parallel to the axis of the running wheel.

[0031] Furthermore, the profiles of the tooth surfaces of the gear teeth in the normal sections at various meshing positions are all convex shapes. The profiles can be a convex curve shape, or the profiles can also be a composite shape with a straight line in the middle section and circular arcs at both side sections.

[0032] When the profile is a convex curve, the curve can be a circular arc or a section of a curve on an ellipse.

[0033] In the embodiment shown in the attached drawings, the curve preferably adopts a circular arc, and the radii of the circular arcs corresponding to the profiles of the tooth surfaces of the gear teeth in the normal sections at various meshing positions are all equal, denoted as R1. The so-called equal radii of the circular arcs means that the radii of the circular arcs of the two tooth surface profiles of the same gear tooth in the same normal section are equal, and the radii of the circular arcs of the tooth surface profiles in the normal sections at different meshing positions of the same gear tooth are also equal. Correspondingly, the profiles of the groove walls of the tooth grooves in the normal sections at various meshing positions are all concave circular arcs, and the radii of the circular arcs are all equal, denoted as R2. The meaning of the so-called equal radii of the circular arcs on the tooth grooves is the same as that of the gear teeth.

[0034] Preferably, R1 < R2, which can eliminate or significantly reduce the edge effect of the gear teeth when the walking wheel meshes with the pin row under heavy load, and is beneficial to avoiding or reducing the sudden increase in the edge stress of the gear teeth due to off-axis load and tooth breakage or premature fatigue failure. Moreover, during the meshing process, due to the elastic deformation of the gear teeth, a curve-shaped line contact can be formed between the tooth surface of the walking wheel gear tooth and the tooth surface of the pin row tooth, significantly reducing the contact stress, increasing the bearing capacity, and significantly improving the wear resistance and service life.

[0035] As a further preferred technical solution, the ratio of R1 to R2 is controlled between 0.85 and 0.98. In this way, on the one hand, the edge effect of the shearer walking wheel under heavy load is avoided, and the stress concentration at the edge of the gear teeth of the walking wheel in the tooth width direction is prevented from cracking. On the other hand, the gear teeth can maintain a high strength at the same time.

[0036] As Figure 4 、 5 shown, a pair of tooth grooves in the same phase are connected, and a step 22 is formed between the same-side groove walls 21 and 23 of the corresponding pair of tooth grooves at the connection. The so-called step is relative to the concave surface characteristics of the groove walls 21 and 23. Therefore, the connection is significantly narrowed compared with the tooth groove. The surface shape of the step 22 is not specifically limited, but the side line of the step 22 in the normal section at each meshing position is preferably a straight line, with a simple structure and easy to process.

[0037] As Figure 5 shown, when the output force of the walking wheel increases, if the tooth profile of the pin row is a large circular arc in the cross-section along the tooth width direction, the tooth profile cross-sectional area will be reduced a lot compared with the structure set as Figure 4 asFigure 5 the area of the shaded part in [description], which greatly weakens the strength of the pin row tooth profile, resulting in a reduction in the reliability of the pin row. In severe cases, it may lead to the fracture of the pin row. The present invention adopts Figure 4 the structure shown in [description], where the double-row tooth grooves are connected by a narrowed notch between the paired tooth grooves, which can prevent the pin row from breaking in the middle of the tooth width direction and improve the load-bearing capacity of the pin row tooth profile.

[0038] The pin row has several sections, which are arranged in sequence along the length direction of the working surface to form the track of the walking wheel. There are 4-8 tooth grooves arranged in a single row on a single section of the pin row. When the walking wheel meshes with the pin row and moves, due to the S-shaped movement of the mining machine in the pit, or although the shearer is moving in a straight line section, but due to the uneven pushing of the scraper conveyor on the working surface or the undulation of the working surface, an angle α often occurs between adjacent two sections of the pin row (as Figure 6 shown). At this time, although the theoretical contact point between the teeth of the walking wheel and the tooth grooves of the pin row deviates from the symmetric center plane of the tooth grooves in the tooth width direction, the two can still maintain an arc curve meshing, and there will be no situation like the teeth of the traditional cylindrical gear where the edge contact point meshing causes a large increase in stress and ultimately leads to tooth surface cracking. At the same time, the meshing force F between the walking wheel and the pin row can be decomposed into mutually perpendicular component forces Fn and Ft, as Figure 6 shown. The meshing component force Fn has a tendency to push the walking wheel of the shearer to move the contact point between the teeth and the tooth grooves towards the symmetric center plane of the tooth grooves in the tooth width direction. Therefore, it can spontaneously improve the meshing state and improve the reliability of the walking system. It can be seen that the walking system of the present invention can well adapt to the horizontal bending of the walking wheel track, and has an automatic guiding effect, improves the meshing state, and extends the service life of the walking system.

[0039] The walking wheel can adopt a large module walking wheel. Due to the adoption of the meshing structure of the present invention, the corresponding shearer walking system can meet the requirements of large mining height and high power occasions for large traction force, and at the same time can maintain high reliability and adaptability to the horizontal bending of the walking track.

Claims

1. A high-load coal shearer traveling system, comprising a traveling wheel and a pin row that mesh with each other, characterized in that: The traveling wheel is provided with double-row teeth. The structural parameters of the double-row teeth are the same and the phases are consistent. The double-row teeth are machined on the same gear blank. The pin row is provided with double-row tooth grooves. The structural parameters of the double-row tooth grooves are the same and the phases are consistent. A pair of tooth grooves with the same phase are connected. A step is formed between the same-side groove walls of the corresponding pair of tooth grooves at the connection. The teeth and the tooth grooves are meshed in rows correspondingly. The tooth surface of the tooth is an outwardly convex surface in the tooth width direction. Correspondingly, the groove wall of the tooth groove is an inwardly concave surface in the tooth width direction. The traveling wheel and the pin row are in a state of mutually concave-convex fitting in the normal section at each meshing position of the tooth profile curve of any tooth. The contour of the tooth surface of the tooth in the normal section at each meshing position is an outwardly convex shape. The contour is an outwardly convex curve. The curve is an arc. And the radius of the arc corresponding to the contour of the tooth surface of the tooth in the normal section at each meshing position is equal, denoted as R1. The contour of the groove wall of the tooth groove in the normal section at each meshing position is an inwardly concave arc, and the radius of the arc is equal, denoted as R2, and R1 < R2.

2. The high-load coal shearer travel system according to claim 1, characterized in that: The traveling wheel adopts spur gears. The single-row teeth and the tooth grooves in meshing are symmetric in their respective tooth width directions.

3. The high-load coal shearer walking system according to claim 2, characterized in that: The ratio of R1 to R2 is between 0.85 and 0.

98.

4. The high-load coal shearer traveling system according to claim 1, 2 or 3, characterized in that: The pin row has several sections, which are arranged in sequence along the length direction of the working surface to form the track of the traveling wheel.

5. The high-load coal shearer traveling system according to claim 1, 2 or 3, characterized in that: There are 4 - 8 tooth grooves arranged in a single row on a single section of the pin row.

6. The high-load shearer traveling system according to claim 1, 2 or 3, characterized in that: The traveling wheel is a large-module traveling wheel.

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