Chain tensioning device, drag chain system and coal mining machinery

Abstract

The invention relates to the technical field of coal mining equipment, in particular to a chain tensioning device, a drag chain system and coal mining machinery. The chain tensioning device comprises an emulsion driving mechanism, a lead screw mechanism and a hydraulic mechanism. The fixed end of the emulsion driving mechanism is fixed in the cable trough; the lead screw mechanism comprises a rotating section and a linear moving section which are connected with each other, the driving end of the emulsion driving mechanism is connected with the rotating section of the lead screw mechanism, and the linear moving section of the lead screw mechanism is connected with the tail wheel wound with the chain; the hydraulic mechanism is arranged on a hydraulic pipeline connected to the emulsion driving mechanism and used for detecting and adjusting the pressure of liquid in the hydraulic pipeline. According to the chain tensioning device, the drag chain system and the coal mining machine, the situation that the chain is too loose or too tight, and consequently the chain is abraded can be avoided; and the hydraulic control system does not need to be repeatedly started, and has the advantages of simple structure, simplicity in operation, reduction of the labor intensity of workers and timely response.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mining equipment, and in particular to a chain tensioning device, a drag chain system and a coal mining machine. Background Art

[0002] In fully mechanized automatic working faces, automatic cable dragging systems are usually used to solve the problem of multiple superposition and bending of the cable clamps of coal mining machines. In the automatic cable dragging system, the cable dragging motor drives the sprocket to rotate, and the sprocket drives the circular chain around the sprocket and the tail wheel to drag the cable dragging trolley to reciprocate in the cable trough. The cable dragging trolley drives the cable clamps of the coal mining machine to follow the coal mining machine synchronously, always maintaining the same direction and half-speed operation with the coal mining machine. The cable dragging chain reciprocates under the action of traction, which inevitably produces wear and elongation, causing the chain to slacken, causing the system to respond slowly and affecting the cable dragging effect. Therefore, keeping the real-time tension of the cable dragging chain can effectively improve the use effect of the automatic cable dragging system, and at the same time greatly reduce the number of times the chain needs to be stopped and cut off due to the slack of the cable dragging chain, reduce the labor intensity of workers, and improve production efficiency.

[0003] The chain tensioning device of the existing coal mining machine cable system is driven by a hydraulic cylinder and hinged with a screw rod. During the chain tightening process, the hydraulic control system needs to be repeatedly opened and the sleeve of the screw rod assembly needs to be screwed with an extension rod. This has problems of complex structure and operation, resulting in high labor intensity for operators. Summary of the invention

[0004] The present invention provides a chain tensioning device, a drag chain system and a coal mining machine, which are used to solve the problems of complex structure and operation of the chain tensioning device of the coal mining machine drag cable system in the prior art, resulting in the defect of high labor intensity for operators.

[0005] The present invention provides a chain tensioning device, comprising: an emulsion driving mechanism, a screw mechanism and a hydraulic mechanism; The fixed end of the emulsion driving mechanism is fixed to the cable trough; The screw mechanism comprises a rotating section and a linear moving section connected to each other, the driving end of the emulsion driving mechanism is connected to the rotating section of the screw mechanism, and the linear moving section of the screw mechanism is connected to a tail wheel around which a chain is coiled; The hydraulic mechanism is arranged on a hydraulic pipeline connected to the emulsion driving mechanism, and is used to detect and adjust the liquid pressure in the hydraulic pipeline.

[0006] According to the chain tensioning device provided by the present invention, the emulsion driving mechanism comprises: An emulsion motor connected to an emulsion pump station; A reducer has one end connected to the driving end of the emulsion motor and the other end connected to the rotating section of the screw mechanism.

[0007] The chain tensioning device provided according to the present invention further includes: a connecting seat, which is fixed in the cable trough, and one end of the connecting seat is connected to the emulsion motor.

[0008] According to the chain tensioning device provided by the present invention, the cable trough includes: a trough seat; the connecting seat includes: a welding plate, and the emulsion driving mechanism is fixed in the trough seat through the welding plate.

[0009] According to the chain tensioning device provided by the present invention, the rotating section of the screw mechanism includes a threaded sleeve; the linear moving section of the screw mechanism includes a screw rod, and the screw rod and the threaded sleeve are engaged with each other.

[0010] According to the chain tensioning device provided by the present invention, the screw mechanism further comprises: a locking nut, which is sleeved on the screw rod and located on a side of the screw sleeve away from the emulsion driving mechanism.

[0011] According to the chain tensioning device provided by the present invention, the hydraulic mechanism includes: an overflow valve, a reversing valve, a first pressure detection device and a second pressure detection device which are sequentially arranged on the hydraulic pipeline; the first pressure detection device is located at the liquid inlet of the emulsion driving mechanism, and the second pressure detection device is located at the liquid outlet of the emulsion driving mechanism.

[0012] According to the chain tensioning device provided by the present invention, the pressure difference between the inlet and outlet is obtained according to the pressure values ​​of the first pressure detection device and the second pressure detection device; and the liquid inlet amount of the emulsion is adjusted according to the comparison result of the pressure difference between the inlet and outlet and the preset pressure threshold.

[0013] The present invention further provides a drag chain system, comprising: the chain tensioning device in the embodiment of the present invention.

[0014] The present invention further provides a coal mining machine, comprising: a chain tensioning device or a drag chain system in an embodiment of the present invention.

[0015] The present invention provides a chain tensioning device, comprising: an emulsion driving mechanism, a screw mechanism and a hydraulic mechanism. The fixed end of the emulsion driving mechanism is fixed on a cable trough; the screw mechanism comprises a rotating section and a linear moving section connected to each other, the driving end of the emulsion driving mechanism is connected to the rotating section of the screw mechanism, and the linear moving section of the screw mechanism is connected to the tail wheel around which the chain is coiled; the hydraulic mechanism is arranged on a hydraulic pipeline connected to the emulsion driving mechanism, and is used to detect and adjust the liquid pressure in the hydraulic pipeline. The present invention provides a chain tensioning device, wherein the hydraulic mechanism is located on the hydraulic pipeline where the emulsion driving mechanism is located, detects and adjusts the liquid pressure in the hydraulic pipeline, and by adjusting the liquid pressure, further adjusts the mechanical energy output by the emulsion driving mechanism, thereby adjusting the tension of the chain, and avoiding the situation where the chain is too loose or too tight, resulting in chain wear; there is no need to set up structures such as extension rods, and there is no need to repeatedly open the hydraulic control system to complete the tensioning of the chain, and it has the advantages of simple structure, simple operation, reduced labor intensity of staff, and timely response.

[0016] Furthermore, the present invention also provides a drag chain system, which includes the chain tensioning device provided by the present invention, and therefore has the same advantages as above.

[0017] Furthermore, the present invention also provides a coal mining machine, which includes the chain tensioning device or drag chain system provided by the present invention, and therefore has the same advantages as above. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic structural diagram of a chain tensioning device provided in one embodiment of the present invention.

[0020] Figure 2 It is a schematic diagram of the structure of a lead screw mechanism provided in one embodiment of the present invention.

[0021] Figure 3 It is a front view of a connecting socket provided in one embodiment of the present invention.

[0022] Figure 4 It is a left side view of a connecting socket provided in one embodiment of the present invention.

[0023] Figure 5 It is a structural schematic diagram of a hydraulic mechanism provided in one embodiment of the present invention.

[0024] Reference numerals: 1-connecting seat; 2-emulsion motor; 3-reducer; 4-screw mechanism; 5-tail wheel; 7-liquid inlet high-pressure pipeline; 8-overflow valve; 9-reversing valve; 10-first pressure detection device; 11-second pressure detection device; 12-liquid return low-pressure pipeline; 101-groove seat; 102-welding plate; 41-screw sleeve; 42-locking nut; 43-screw. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the description of the present embodiment, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present embodiment and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present embodiment.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this embodiment, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0028] In this embodiment, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in this embodiment can be understood according to specific circumstances.

[0029] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0030] Combine the following Figure 1-Figure 5 The present invention describes a chain tensioning device, which comprises an emulsion driving mechanism, a screw mechanism 4 and a hydraulic mechanism.

[0031] Among them, the fixed end of the emulsion driving mechanism is fixed on the cable trough; the screw mechanism 4 includes a rotating section and a linear moving section connected to each other, the driving end of the emulsion driving mechanism is connected to the rotating section of the screw mechanism 4, and the linear moving section of the screw mechanism 4 is connected to the tail wheel 5 around which the chain is coiled; the hydraulic mechanism is arranged on the hydraulic pipeline connected to the emulsion driving mechanism, and is used to detect and adjust the liquid pressure in the hydraulic pipeline.

[0032] Specifically, the emulsion driving mechanism is connected to the emulsion pump station, which provides high-pressure emulsion as a working medium to provide a power source for the chain tensioning device.

[0033] The emulsion driving mechanism converts the liquid pressure energy of the high-pressure emulsion into mechanical energy and can output rotational motion, which is used to drive the rotating section of the screw mechanism 4 to rotate, and the rotation of the rotating section drives the linear motion of the linear moving section. One end of the linear moving section is hinged to the tail wheel 5 around which the chain is coiled, and the linear motion of the linear moving section drives the tail wheel 5 to move, thereby adjusting the chain tension. The function of the screw mechanism 4 is to convert rotary motion into linear motion.

[0034] The hydraulic mechanism is located on the hydraulic pipeline where the emulsion drive mechanism is located. It detects and adjusts the liquid pressure in the hydraulic pipeline. By adjusting the liquid pressure, the mechanical energy output by the emulsion drive mechanism is adjusted, thereby adjusting the tension of the chain to avoid the chain being too loose or too tight, which leads to chain wear.

[0035] Specifically, by detecting the liquid pressure, the tension of the chain can be determined. If the chain is too tensioned, the emulsion drive mechanism is adjusted to bear too large a load, and the liquid pressure difference between the inlet and outlet is too large. At this time, the input pressure of the emulsion at the inlet should be reduced, so that the chain is slightly relaxed from a tight state to avoid chain wear. If the chain is too loose, the emulsion drive mechanism is adjusted to bear too small a load, and the input pressure of the emulsion at the inlet needs to be increased to drive the screw mechanism 4 to move, thereby tightening the chain.

[0036] Moreover, the present invention can adaptively adjust the input pressure of the emulsion through the above-mentioned hydraulic mechanism and ensure that the chain tension is controllable; there is no need to repeatedly open the hydraulic control system to complete the chain tensioning. The present invention can ensure the chain tensioning in real time by adjusting the liquid pressure according to the liquid pressure detected in the hydraulic pipeline.

[0037] The present invention provides a chain tensioning device, comprising: an emulsion driving mechanism, a screw mechanism 4 and a hydraulic mechanism. The fixed end of the emulsion driving mechanism is fixed to the cable trough; the screw mechanism 4 comprises a rotating section and a linear moving section connected to each other, the driving end of the emulsion driving mechanism is connected to the rotating section of the screw mechanism 4, and the linear moving section of the screw mechanism 4 is connected to the tail wheel 5 around which the chain is coiled; the hydraulic mechanism is arranged on the hydraulic pipeline connected to the emulsion driving mechanism, and is used to detect and adjust the liquid pressure in the hydraulic pipeline. The present invention provides a chain tensioning device, wherein the hydraulic mechanism is located on the hydraulic pipeline where the emulsion driving mechanism is located, detects and adjusts the liquid pressure in the hydraulic pipeline, and by adjusting the liquid pressure, further adjusts the mechanical energy output by the emulsion driving mechanism, thereby adjusting the tension of the chain, avoiding the situation where the chain is too loose or too tight, resulting in chain wear; there is no need to set up structures such as extension rods, and there is no need to repeatedly open the hydraulic control system to complete the tensioning of the chain, and it has the advantages of simple structure, simple operation, reduced labor intensity of staff, and timely response.

[0038] In one embodiment of the present invention, the emulsion driving mechanism includes: an emulsion motor 2 and a reducer 3. The emulsion motor 2 is connected to the emulsion pump station, and the emulsion motor 2 is provided with high-pressure emulsion through the emulsion pump station. The high-pressure emulsion enters from the liquid inlet of the emulsion motor 2, driving the emulsion motor 2 to rotate, and the low-pressure emulsion is discharged from the liquid outlet and flows back to the emulsion pump station, thereby realizing the conversion of the hydraulic energy of the emulsion into mechanical energy; one end of the reducer 3 is connected to the driving end of the emulsion motor 2, and the other end is connected to the rotating section of the screw mechanism 4. Specifically, the output shaft of the emulsion motor 2 is connected to the reducer 3, and after the speed is reduced by the reducer 3, the rotating section of the screw mechanism 4 is driven to rotate. The transmission ratio of the reducer 3 can be designed according to actual conditions.

[0039] In the above embodiment, the torque formed by the emulsion motor 2 drives the screw mechanism 4 to move, thereby realizing the tensioning of the chain. The emulsion motor 2 can achieve the reversal of the emulsion motor 2 by adjusting the liquid inlet direction of the high and low pressure emulsions, thereby driving the screw mechanism 4 to move in the opposite direction, thereby realizing the loosening of the chain, so that the staff can remove and replace the worn chain. After the replacement is completed, the emulsion motor 2 is controlled to rotate forward to realize the tensioning of the chain.

[0040] In one embodiment of the present invention, the chain tensioning device further includes: a connecting seat 1, the connecting seat 1 is fixed in the cable trough, and one end of the connecting seat 1 is connected to the emulsion motor 2. Specifically, the function of the connecting seat 1 is to fix the emulsion motor 2 in the cable trough, provide an installation position for the emulsion motor 2, and ensure that the emulsion motor 2 does not move during operation.

[0041] In one embodiment of the present invention, the cable trough comprises: a trough seat 101; the connecting seat 1 comprises: a welding plate 102, and the emulsion driving mechanism is fixed in the trough seat 101 through the welding plate 102. Specifically, the cable trough has a trough seat 101, such as Figure 3 and Figure 4 As shown, the slot seat 101 is a U-shaped slot seat 101, and the emulsion motor 2 can be assembled into the U-shaped slot seat 101. One end of the welding plate 102 is welded and fixed to the U-shaped slot seat 101, and the other end is welded and fixed to the emulsion motor 2, so that the emulsion motor 2 is fixed in the U-shaped slot seat 101, ensuring the stability of the emulsion motor 2 and avoiding the damage to the reducer 3 and the screw mechanism 4 caused by the movement of the emulsion motor 2.

[0042] In one embodiment of the present invention, the rotating section of the screw mechanism 4 includes: a screw sleeve 41; the linear moving section of the screw mechanism 4 includes: a screw rod 43, and the screw rod 43 and the screw sleeve 41 are engaged with each other. In this embodiment, the screw structure is composed of a screw sleeve 41 and a screw rod 43, the screw sleeve 41 has an internal thread, and the screw rod 43 has an external thread, and the two are connected to each other by threads. The screw sleeve 41 rotates, thereby driving the screw rod 43 to perform linear motion, and the screw sleeve 41 can rotate forward or reverse, and correspondingly drives the screw rod 43 to extend or retract.

[0043] In one embodiment of the present invention, the screw mechanism 4 further includes: a locking nut 42, which is sleeved on the screw rod 43 and is located on the side of the screw sleeve 41 away from the emulsion driving mechanism. In this embodiment, the screw mechanism 4 is also equipped with a locking nut 42, which is mainly used to prevent the screw sleeve 41 from loosening due to vibration or other external forces generated when the emulsion motor 2 is working. Because one end of the screw sleeve 41 is connected to the reducer 3, the locking nut 42 is arranged at the other end of the screw sleeve 41. Preferably, the locking nut can be in the form of a self-locking nut or a welded locking nut.

[0044] In one embodiment of the present invention, the hydraulic mechanism includes: a relief valve 8, a reversing valve 9, a first pressure detection device 10 and a second pressure detection device 11 arranged in sequence on the hydraulic pipeline; the first pressure detection device 10 is located at the liquid inlet of the emulsion driving mechanism, and the second pressure detection device 11 is located at the liquid outlet of the emulsion driving mechanism. Figure 5 As shown, a relief valve 8, a reversing valve 9, a first pressure detection device 10 and a second pressure detection device 11 are sequentially arranged at the liquid inlet of the hydraulic pipeline along the moving direction of the emulsion, wherein the pressure of the emulsion fluid entering the emulsion motor 2 is adjusted by the relief valve 8 on the hydraulic pipeline, and the reversing valve 9 can change the flow direction of the emulsion, which can be as follows: Figure 5 The structure shown performs clockwise or counterclockwise flow, thereby realizing the forward and reverse rotation of the emulsion motor 2, and then drives the screw mechanism 4 to drive the tail wheel 5 to realize forward movement, so that the chain is tightened, or reverse movement to relax the chain. The first pressure detection device 10 and the second pressure detection device 11 are specifically used to detect the inlet pressure and outlet pressure of the emulsion motor 2, and the pressure difference between the inlet and outlet can be calculated through the inlet pressure and outlet pressure.

[0045] In the above embodiment, a high-pressure ball valve may be further provided in the hydraulic mechanism. The high-pressure ball valve may be provided upstream of the relief valve 8 to control the emulsion from entering the hydraulic pipeline.

[0046] In the above embodiment, the hydraulic pipeline connected to the emulsion driving mechanism includes a high-pressure liquid inlet pipeline 7 near the liquid inlet and a low-pressure liquid return pipeline 12 near the liquid outlet. The high-pressure emulsion enters the hydraulic pipeline through the liquid inlet via the high-pressure liquid inlet pipeline 7, driving the emulsion motor 2 to rotate. The high-pressure emulsion is converted into low-pressure emulsion and flows back to the emulsion pump station through the liquid outlet via the low-pressure liquid return pipeline 12, so that the emulsion can be recycled.

[0047] In one embodiment of the present invention, the pressure difference between the inlet and outlet is obtained according to the pressure values ​​of the first pressure detection device 10 and the second pressure detection device 11; and the amount of emulsion inlet is adjusted according to the comparison result of the pressure difference between the inlet and outlet and the preset pressure threshold. Specifically, the pressure difference between the inlet and outlet is calculated based on the difference between the inlet pressure detected by the first pressure detection device 10 and the outlet pressure detected by the second pressure detection device 11, and the load of the chain on the emulsion motor 2 during the tensioning process can be obtained, and the preset pressure threshold is set. The pressure difference between the inlet and outlet calculated above is compared with the preset pressure threshold. If it is greater than the preset pressure threshold, it indicates that the load of the chain on the emulsion motor 2 is too large, and the chain may be worn due to excessive tension; if it is less than or equal to the preset pressure threshold, it indicates that the load of the chain on the emulsion motor 2 is too small, and the chain may be in a too loose state. By comparing with the preset pressure threshold, the current tension or relaxation state of the chain can be determined, and the amount of emulsion flowing into the chain can be adjusted accordingly. If the pressure difference between the inlet and outlet is greater than the preset pressure threshold, the amount of emulsion flowing into the chain is controlled to be reduced, thereby reducing the tensioning effect of the chain tensioning device on the chain; if the pressure difference between the inlet and outlet is less than or equal to the preset pressure threshold, the amount of emulsion flowing into the chain is controlled to be increased, thereby increasing the tensioning effect of the chain tensioning device on the chain.

[0048] In the above embodiment, the first pressure detection device 10 and the second pressure detection device 11 can adopt pressure gauges, pressure sensors or pressure switches, etc. Of course, the first pressure detection device 10 and the second pressure detection device 11 can also adopt a differential pressure gauge to realize the pressure difference detection of the inlet and outlet.

[0049] The present invention further provides a drag chain system, which includes: the chain tensioning device in the above embodiment of the present invention.

[0050] The present invention further provides a drag chain system, which includes the chain tensioning device provided by the present invention, and therefore has the same advantages as above.

[0051] The present invention further provides a coal mining machine, which may be a coal mining machine. The coal mining machine comprises: the chain tensioning device or the drag chain system in the above embodiment of the present invention.

[0052] The present invention also provides a coal mining machine, which includes the chain tensioning device or drag chain system provided by the present invention, and therefore has the same advantages as above.

[0053] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, i.e., they may be located in one place, or they may be distributed over multiple units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. Those of ordinary skill in the art may understand and implement the present invention without creative effort.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A chain tensioning device, characterized in that: include: Emulsion drive mechanism, screw mechanism (4) and hydraulic mechanism; The fixed end of the emulsion driving mechanism is fixed to the cable trough; The screw mechanism (4) comprises a rotating section and a linear moving section connected to each other, the driving end of the emulsion driving mechanism is connected to the rotating section of the screw mechanism (4), and the linear moving section of the screw mechanism (4) is connected to a tail wheel (5) around which a chain is wound; The hydraulic mechanism is arranged on a hydraulic pipeline connected to the emulsion driving mechanism, and is used to detect and adjust the liquid pressure in the hydraulic pipeline.

2. The chain tensioner according to claim 1, characterized in that: The emulsion driving mechanism includes: An emulsion motor (2) connected to an emulsion pump station; A reducer (3) has one end connected to the driving end of the emulsion motor (2) and the other end connected to the rotating section of the screw mechanism (4).

3. The chain tensioner according to claim 2, characterized in that: Also includes: A connecting seat (1), wherein the connecting seat (1) is fixed in the cable trough, and one end of the connecting seat (1) is connected to the emulsion motor (2).

4. The chain tensioner according to claim 3, characterized in that: The cable trough comprises a trough seat (101); the connection seat (1) comprises a welding plate (102), and the emulsion driving mechanism is fixed in the trough seat (101) via the welding plate (102).

5. The chain tensioner according to claim 1, characterized in that: The rotating section of the screw mechanism (4) comprises a screw sleeve (41); the linear moving section of the screw mechanism (4) comprises a screw rod (43), and the screw rod (43) and the screw sleeve (41) are engaged with each other.

6. The chain tensioner according to claim 5, characterized in that: The screw mechanism (4) further comprises: a locking nut (42), wherein the locking nut (42) is sleeved on the screw rod (43) and is located on a side of the screw sleeve (41) away from the emulsion driving mechanism.

7. The chain tensioner according to any one of claims 1 to 6, characterized in that: The hydraulic mechanism comprises: an overflow valve (8), a reversing valve (9), a first pressure detection device (10) and a second pressure detection device (11) which are arranged in sequence on a hydraulic pipeline; the first pressure detection device (10) is located at a liquid inlet of an emulsion driving mechanism, and the second pressure detection device (11) is located at a liquid outlet of the emulsion driving mechanism.

8. The chain tensioner according to claim 7, characterized in that: Obtaining the pressure difference between the liquid inlet and the liquid outlet according to the pressure values ​​of the first pressure detection device (10) and the second pressure detection device (11); The amount of emulsion inlet is adjusted according to the comparison result between the pressure difference between the inlet and outlet and the preset pressure threshold.

9. A drag chain system, characterized in that: include: A chain tensioner as claimed in any one of claims 1 to 8.

10. A coal mining machine, characterized in that: include: The chain tensioning device according to any one of claims 1 to 8 or the drag chain system according to claim 9.

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