CN219932608U

CN219932608U - Stroke measurement hydraulic cylinder for coal mining machine

Info

Publication number: CN219932608U
Application number: CN202320757068.9U
Authority: CN
Inventors: 朱红; 李庆亮; 翟雨生; 章立强; 胡璟; 刘凯; 郭岱; 朱信平; 贺新星; 牛永峰
Original assignee: Tiandi Shanghai Mining Equipment Technology Co Ltd
Current assignee: Tiandi Shanghai Mining Equipment Technology Co Ltd
Priority date: 2023-04-07
Filing date: 2023-04-07
Publication date: 2023-10-31
Anticipated expiration: 2033-04-07

Abstract

The utility model relates to a stroke measurement hydraulic cylinder for a coal mining machine, which comprises a cylinder barrel, a cylinder bottom, a cylinder cover, a piston rod and a magnetostrictive displacement sensor, wherein the cylinder bottom is fixed at one end opening of the cylinder barrel and seals the corresponding end opening, the cylinder cover is fixed at the other end opening of the cylinder barrel and seals the corresponding end opening, the cylinder barrel, the cylinder cover and the cylinder bottom form a cylinder body, the piston is sleeved and fixed on the piston rod, the piston is in sliding fit with the cylinder barrel in the cylinder barrel, the piston rod is a hollow piston rod, the magnetostrictive displacement sensor comprises a sensing electronic head, a measuring rod and a position magnet, the sensing electronic head is arranged in the cylinder bottom, the measuring rod and the position magnet are arranged in the piston rod, the measuring rod extends into a central hole of the piston rod and simultaneously penetrates through a central hole of the position magnet, and the sensing electronic head is positioned in an axial groove through a positioning structure. The utility model can adapt to the working environment of the coal mining machine, is used for realizing the mining height monitoring of the coal mining machine, and can meet the control requirements of wide range and high precision.

Description

Stroke measurement hydraulic cylinder for coal mining machine

Technical Field

The utility model relates to a hydraulic cylinder, in particular to a hydraulic cylinder with a magnetostriction displacement sensor, which can well meet the use working condition of a coal mining machine and the control requirements of wide range and high precision.

Background

The forward automation and unmanned development of the coal mining machine are used as the technical support for the automatic height-adjusting control of the roller, and the accuracy and reliability of the height-mining monitoring are more and more important. However, the current common method is to install a swing angle sensor in the rotation axis of the rocker arm of the coal mining machine to measure the height, and the measuring device has the problem of reduced measuring precision due to the influence of abrasion of an installation and connection mechanism of the measuring device, and meanwhile, some units are limited by the space of a machine body or cannot install the swing angle sensor due to interference among components, so that the height monitoring cannot be realized.

Currently, in a hydraulic cylinder adopting a stroke measuring device, a displacement sensor cannot be used for a coal mining machine due to the fact that the control requirement of a large range and high precision is difficult to meet, and a magnetostrictive displacement sensor cannot be used for the coal mining machine working environment at present although the range and the precision of the magnetostrictive displacement sensor can be used for the coal mining machine due to the fact that the displacement sensor is external and semi-external installation is difficult to adapt to severe working conditions and narrow spaces of the coal mining machine.

Disclosure of Invention

The utility model aims to provide a travel measurement hydraulic cylinder for a coal mining machine, which can be adapted to the working environment of the coal mining machine, is used for realizing the monitoring of the mining height of the coal mining machine, and can meet the control requirements of wide range and high precision.

The main technical scheme of the utility model is as follows:

the utility model provides a stroke measurement pneumatic cylinder for coal-winning machine, includes cylinder, cylinder bottom, cylinder cap, piston rod and magnetostriction displacement sensor, and the cylinder bottom is fixed in the one end opening part of cylinder and is sealed corresponding end opening, and the cylinder cap is fixed in the other end opening part of cylinder and is sealed corresponding end opening, and cylinder, cylinder cap and cylinder bottom constitute the cylinder body, and the piston sleeve is established and is fixed on the piston rod, and the piston is in cylinder and cylinder sliding fit, and the piston rod is hollow piston rod, magnetostriction displacement sensor includes sensing electronic head, measuring staff and position magnet, and sensing electronic head installs in the cylinder bottom, measuring staff and position magnet install in the piston rod, still are equipped with hole in the piston rod and carry out axial spacing to position magnet, and the measuring staff stretches into the centre bore of piston rod and passes from the centre bore of position magnet simultaneously.

The travel measuring hydraulic cylinder for the coal mining machine further comprises an outgoing line transition sleeve and a connector, wherein a bent aviation plug is arranged on the connector, an axial groove and a lateral groove which are communicated are formed in the cylinder bottom, the axial groove is opened in the inner side end face of the cylinder bottom, the lateral groove is opened in the outer cylindrical surface of the cylinder bottom, the sensing electronic head is fixedly arranged in the axial groove, the outgoing line transition sleeve is fixed on the outer cylindrical surface of the cylinder bottom through a top flange structure of the sensing electronic head, the other parts of the outgoing line transition sleeve are embedded into the lateral groove, a radial seal is arranged between the outgoing line transition sleeve and the corresponding matching surface of the cylinder bottom, the connector is fixedly arranged in an inner hole of the outgoing line transition sleeve, a radial seal is arranged between the connector and the corresponding matching surface of the outgoing line transition sleeve, one part of the bent aviation plug is positioned in the outgoing line transition sleeve, the other part of the bent aviation plug is positioned outside the cylinder bottom and extends along the outer cylindrical surface of the cylinder bottom, and a sensing wire of the magnetostrictive displacement sensor is led out from the sensing electronic head and is electrically connected with the aviation plug through the connector.

And the silica gel is filled in the residual space of the outlet transition sleeve after the connector is arranged in the inner hole of the outlet transition sleeve.

The stroke measurement hydraulic cylinder for the coal mining machine further comprises a protection seat, the protection seat is detachably and fixedly installed on the outer cylindrical surface of the cylinder bottom and covers the notch of the lateral groove and the bent aviation plug, and the protection seat is provided with a wire outlet hole.

The protection seat is formed by welding a quick connector and a protection cover, the quick connector serves as the wire outlet hole, and the wire outlet angle of the quick connector is 145 degrees.

The quick connector is connected with a high-pressure rubber tube.

The cylinder barrel extends in the front-back direction, the lateral groove is provided with an upper part and a lower part, two oil inlet and outlet ports are respectively arranged at the position, close to the left side or close to the right side, of the upper part and the lower part of the cylinder bottom, a balance valve installation position is arranged at the position, close to the right side or close to the left side, of the outer side of the cylinder bottom, when one of the two oil inlet and outlet ports at the upper part and the lower part is in a use state, a joint is arranged on the two oil inlet and outlet ports, and a plug is arranged on the other two oil inlet and outlet ports; when one of the lateral grooves is in a use state, a blank cap is arranged in the other lateral groove, and the corresponding protection seat is replaced by a temporary protection cover; the outer wall of the cylinder barrel is also welded with a section of oil duct, one end oil port of the oil duct is communicated with the rod cavity, the other end oil port is communicated with one oil inlet and outlet above and one oil inlet and outlet below through an oil hole arranged in the cylinder bottom, and the other oil inlet and outlet above and the other oil inlet and outlet below are communicated with the rodless cavity.

A strip-shaped groove is arranged in the entity structure with the cylinder bottom facing outwards, a protection plate is arranged at the edge of a notch of the strip-shaped groove, and the strip-shaped groove and the protection plate enclose the balance valve installation position of the embedded protection structure.

The sensing electronic head is positioned in the axial groove through a positioning structure, the positioning structure comprises a mounting sleeve, a positioning screw, a locking screw and a sealing screw plug, the sensing electronic head is fixed in the mounting sleeve, the mounting sleeve is mounted in the axial groove, a radial limiting hole communicated with the axial groove is further formed in the cylinder bottom, the positioning screw, the sealing screw plug and the locking screw are sequentially connected in a threaded mode from inside to outside in the radial limiting hole, the head of the positioning screw is just embedded into the limiting groove positioned on the outer cylindrical surface of the mounting sleeve, and the outer side of the sealing screw plug abuts against the positioning screw.

The installation sleeve comprises a base and a gland, wherein the base is an annular part, a positioning groove is formed in the base, the sensing electronic head is installed in the positioning groove, and the gland is fixed in a threaded hole of the base through threaded connection.

The beneficial effects of the utility model are as follows:

because the magnetostrictive displacement sensor is fully arranged in the cylinder body of the hydraulic cylinder, the integration level is high, the whole hydraulic cylinder is compact in structure, almost no extra occupation of the body space of the coal mining machine is caused, and adverse effects on stroke measurement caused by the environment outside the cylinder body of the hydraulic cylinder are greatly reduced, so that the hydraulic cylinder can be well adapted to the use condition of the coal mining machine, and the hydraulic cylinder is good in stability.

Because the cable and the outgoing line part of the magnetostrictive displacement sensor are provided with reliable dustproof and waterproof and safety protection measures, the cable and the outgoing line part can be well adapted to the use working condition of the coal mining machine, and meanwhile, the related protection measures have simple and proper structures, so that the cable and outgoing line part has the convenience of pipeline installation and maintenance.

Because the upper and lower sets of oil inlet and outlet are arranged, the special requirement of uniform interchange of the left and right hydraulic cylinders of the coal mining machine can be met.

In addition, the hydraulic cylinder and the swing angle sensor can form a redundant mechanism of the mining height monitoring system, so that continuous and reliable automatic operation is ensured.

Drawings

FIG. 1 is a schematic diagram of an embodiment of the lift cylinder;

FIG. 2 is a top view of FIG. 1;

FIG. 3 is a right side view of FIG. 1;

FIG. 4 is a partial enlarged view of the outlet of the lift cylinder;

FIG. 5 is a partial enlarged view of the positioning structure of the sensor head;

fig. 6 is a schematic diagram of the height-adjusting cylinder for implementing height measurement.

Reference numerals:

1. a piston rod; 2. a cylinder; 3. a piston; 4. an oil passage; 5. a cylinder bottom; 6. radial limiting holes; 7. a measuring rod; 8. a position magnet; 9. a sensing electronic head; 10. a connector; 11. aviation plug; 12. a wire outlet transition sleeve; 13. a protection seat; 14. an oil inlet and outlet; 15. a cover is closed; 16. a temporary protective cover; 17. a high pressure hose; 18. a set screw; 19. a locking screw; 20. sealing the screw plug; 21. and a balance valve.

Detailed Description

As shown in fig. 1 to 6, the utility model discloses a stroke measurement hydraulic cylinder (which can be simply called a hydraulic cylinder) for a coal mining machine, comprising a cylinder barrel 2, a cylinder bottom 5, a cylinder cover, a piston 3, a piston rod 1 and a magnetostrictive displacement sensor. The cylinder bottom is fixed at one end opening of the cylinder barrel and seals the corresponding end opening, the cylinder cover is fixed at the other end opening of the cylinder barrel and seals the corresponding end opening, and the cylinder barrel, the cylinder cover and the cylinder bottom form a cylinder body. The piston is sleeved and fixed on the piston rod, and the piston is in sliding fit with the cylinder barrel. The piston rod is a hollow piston rod. The magnetostriction displacement sensor comprises a sensing electronic head 9, a measuring rod (containing a waveguide wire) 7 and a position magnet 8, wherein the position magnet is annular, and the measuring rod penetrates through the center of the position magnet during working. The working principle of the magnetostrictive displacement sensor is as follows: the sensor head 9 generates a current pulse which is transmitted in the measuring rod, a circumferential magnetic field is generated outside the measuring rod, and when the magnetic field intersects with the magnetic field generated by the position magnet, a strain mechanical wave pulse signal is generated in the measuring rod due to the magnetostriction effect, and the strain mechanical wave pulse signal is transmitted at a fixed speed and is quickly detected by the sensor head. The transmission time of the strain mechanical wave pulse signal in the measuring rod is in direct proportion to the distance between the position magnet and the sensing electronic head, the distance between the position magnet and the sensing electronic head can be obtained by measuring the transmission time, and the displacement of the position magnet in the extending direction of the measuring rod is calculated by detecting the time difference between the sending of current pulse and the returning of the strain mechanical pulse.

The sensing electronic head 9 is arranged in the cylinder bottom 5, the measuring rod 7 and the position magnet 8 are arranged in the piston rod 1, wherein the measuring rod 7 stretches into the central hole of the piston rod and simultaneously penetrates through the central hole of the position magnet, and the piston rod is internally provided with a check ring for the hole to axially limit the position magnet. The position magnet moves reciprocally along with the piston and the piston rod, the distance between the position magnet and the sensing electronic head changes along with the reciprocating movement of the piston and the piston rod, and the change reflects the position change of the piston and the piston rod relative to the cylinder body due to the fact that the sensing electronic head is fixed in the cylinder bottom. As the current pulse continues to be emitted, a change in travel is induced.

Because the magnetostrictive displacement sensors are all built in the hydraulic cylinders, the whole stroke measurement hydraulic cylinder for the coal mining machine is compact in structure, and adverse effects on stroke measurement caused by the environment outside the hydraulic cylinder body are greatly reduced, so that the stroke measurement hydraulic cylinder for the coal mining machine can be well adapted to the use conditions of the coal mining machine, and is good in stability.

The travel measuring hydraulic cylinder for the coal mining machine further comprises an outgoing line transition sleeve 12 and a connector 10, wherein a bent aviation plug 11 is arranged on the connector. The scattered line that magnetostriction displacement sensor draws forth is connected to the connector, and aviation plug then connects the cable, and the other end of cable will be connected to the sensing center. The aviation plug is adopted to facilitate the installation and replacement of the cable. The cylinder bottom is internally provided with an axial groove and a lateral groove which are communicated, the axial groove is opened at the inner side end face of the cylinder bottom, and the lateral groove is opened at the outer cylindrical surface of the cylinder bottom. The sensing electronic head 9 is fixedly arranged in the axial groove, the outgoing line transition sleeve is fixed on the outer cylindrical surface of the cylinder bottom through the top flange structure of the outgoing line transition sleeve, and the rest parts of the outgoing line transition sleeve are embedded into the lateral groove. In the embodiment shown in the drawings, the outlet transition sleeve is fastened on the outer cylindrical surface of the cylinder bottom through a flange plate on the outlet transition sleeve by 4M 8 screws. Radial sealing is arranged between the outlet transition sleeve and the corresponding matching surface of the cylinder bottom. The connector is fixedly arranged in the inner hole of the outgoing line transition sleeve, and radial sealing is arranged between the connector and the corresponding matching surface of the outgoing line transition sleeve. The two radial seals can prevent underground spray water and dust from entering the hydraulic cylinder, protect electronic components and keep the inside of the cylinder clean. One part of the bent aviation plug is positioned in the outlet transition sleeve, and the other part of the bent aviation plug is positioned outside the cylinder bottom and extends along the outer column surface of the cylinder bottom. The use of the bent aviation plug reduces the height dimension at the junction of the cylinder bottom 5 (this height dimension refers to the linear dimension of the outer cylindrical surface protruding radially from the cylinder bottom) compared to a straight aviation plug. And the sensing wire of the magnetostrictive displacement sensor is led out from the sensing electronic head and then is electrically connected with the aviation plug through the connector.

In the embodiment shown in the drawings, after the four-pin connector is in butt joint with the aviation plug 11, the four-pin connector is locked by M12 threads, and the connector and the aviation plug are reliably and electrically connected in the locked state.

And the residual space after the connector is installed in the inner hole of the outlet transition sleeve is filled with silica gel, so that underground spray water is prevented from entering the cylinder from the connecting thread M12 of the bent aviation plug.

The stroke measurement hydraulic cylinder for the coal mining machine further comprises a protection seat 13, wherein the protection seat is detachably and fixedly arranged on the outer cylindrical surface of the cylinder bottom and shields the notch of the lateral groove and the bent aviation plug from the outside, so that the bent aviation plug is prevented from being extruded and collided by external force. And the protection seat is provided with a wire outlet hole. The protection seat serves as a wire outlet of a stroke measurement hydraulic cylinder for the coal mining machine.

In the embodiment shown in the drawings, the protection seat is formed by welding two parts of a quick connector and a protection cover, the quick connector is used as the wire outlet hole, the wire outlet angle of the quick connector (namely, the included angle between the axis of the quick connector and the extending direction of the adjacent aviation plug) is preferably 145 degrees, and even if the angle of the hydraulic cylinder is changed due to expansion and contraction change, the cable can be ensured to smoothly enter the wire outlet of the tractor shell.

The quick-connect connector is connected with a high-pressure rubber tube 17. The quick connector and the high-pressure rubber tube are used for the cable wiring of the magnetostrictive displacement sensor, so that the dustproof and waterproof effects are achieved, and the cable is prevented from being damaged due to pressure along the cable.

The outlet transition sleeve, the connector, the aviation plug and the protection seat and the radial seal and the silica gel form a seal and safety protection structure of an outlet part of the stroke measurement hydraulic cylinder for the coal mining machine, so that the hydraulic cylinder can reliably and stably work in the working environment of the coal mining machine.

The cylinder barrel extending direction is taken as the front-back direction, the lateral groove is provided with an upper part and a lower part, two oil inlet and outlet ports 14 are respectively arranged at the positions of the upper part and the lower part of the cylinder bottom, which are close to the left side or the right side, and a balance valve mounting position is arranged at the position of the outer side of the cylinder bottom, which is close to the right side or the left side, so as to ensure the interchangeability of mounting of the stroke measuring hydraulic cylinder for the coal mining machine on the left traction part and the right traction part of the same coal mining machine. For this purpose, the cylinder bottom can adopt an up-down symmetrical structure. The balance valve mounting position is preferably arranged on one side which is convenient to mount and maintain in the left-right direction.

When one of the two oil inlet and outlet ports at the upper part and the lower part is in a use state, the two oil inlet and outlet ports are provided with connectors, the connectors are connected with oil pipes, and the other two oil inlet and outlet ports are provided with plugs. When one of the lateral grooves is in use, the other lateral groove is fitted with a blank cap 15 instead of the connector and the corresponding protective seat is replaced with a temporary protective cover 16. The cover 15 is a part that approximates the shape of the connector 10. The temporary protection cover 16 is similar to the protection seat in shape, and the main difference is that the protection seat is the position of the quick-connection joint, and the temporary protection cover is replaced by a non-porous protection plate. The plug, the cover and the guard plate are used for closing the temporarily unused opening. The oil inlet and outlet and aviation plug in the use state are always kept above the hydraulic cylinder so that the oil pipe and the cable can enter the traction machine shell nearby.

An oil passage 4 is welded on the outer wall of the cylinder barrel, an oil port at one end of the oil passage is communicated with the rod cavity, an oil port at the other end of the oil passage is communicated with an oil inlet and outlet at the upper part and an oil inlet and outlet at the lower part through an oil hole arranged in the cylinder bottom, and the other oil inlet and outlet at the upper part and the other oil inlet and outlet at the lower part are communicated with the rodless cavity. The rod cavity and the oil inlet and outlet are connected through the oil duct, so that the diameter of the cylinder barrel is not increased, and interference with the housing of the coal mining machine is avoided.

To facilitate the use of the hydraulic cylinder and the balancing valve 21, a balancing valve mounting position is also provided on the cylinder bottom. In this embodiment, be equipped with the bar recess in the entity structure that the cylinder bottom outwards, the notch edge of bar recess is equipped with the guard plate, and bar recess and guard plate enclose embedded protective structure's balanced valve installation position. The balance valve is sunk into the balance valve after being assembled, so that the impact and damage of external force can be effectively avoided.

The sensing electronic head is positioned in the axial groove through the positioning structure. In this embodiment the location structure includes installation cover, set screw 18, locking screw 19 and sealing plug screw 20, sensing electronic head is fixed in the installation cover, the installation cover is installed in axial recess, still be equipped with in the cylinder bottom with axial recess link up radial spacing hole 6, set screw, sealing plug screw and locking screw are in from inside to outside threaded connection in proper order in radial spacing hole, wherein in the head of set screw just imbeds the spacing recess that is located the installation cover outer cylinder face, prevent installation cover axial float, sealing plug screw supports set screw from the outside, prevents that the pollutant from getting into in the jar through radial spacing hole. The limit groove may be a ring groove.

The installation sleeve can comprise a base and a gland, wherein the base is an annular part, a positioning groove is formed in the base, the sensing electronic head is installed in the positioning groove, and the gland is fixed in a threaded hole of the base through threaded connection. The limiting groove is arranged on the outer cylindrical surface of the base. Meanwhile, a sealing groove is further formed in the outer cylindrical surface of the base, and a sealing ring is installed in the sealing groove and used for radially sealing the mounting sleeve and the cylinder bottom.

The output current (4-20 mA) of the magnetostrictive displacement sensor is firstly transmitted to a sensing center of the coal mining machine and converted into a corresponding displacement digital signal (0 mm-maximum stroke), then the corresponding displacement digital signal is transmitted to a host control system in a bus communication mode, and finally the current mining height data is calculated through a functional relation (see the following formula) between the stroke variation delta L of the oil cylinder and the mining height H of the rocker arm.

The mining height calculation principle is shown in fig. 6, wherein a point O represents the rotation central axis of the roller, a point A represents the hinge axis of the rocker arm and the coal mining machine body, a point B represents the hinge axis of the height adjusting oil cylinder and the rocker arm, and a point C represents the hinge axis of the height adjusting oil cylinder and the coal mining machine body; the length a is the distance from A to C, the length B is the distance from A to B, the length L1 is the distance from A to O, the length H1 is the distance from A to the bottom plate, the length L is the distance from B to C, the length R is the radius of the roller, and the length H is the distance from the highest point of the roller to the bottom plate, namely the height; the angle alpha is the angle between the OA line and the horizontal line, the angle beta is the angle between the OA line and the AB line, the angle theta is the angle between the AB line and the AC line, and the angle gamma is the angle between the AC line and the horizontal line.

The lengths and angles have the following geometrical relationships:

for a given shearer and a given working surface, the lengths a, b, L1, H1, R and angles β and γ are known and fixed, the length L can be determined by the magnetostrictive displacement sensor measuring the stroke variation Δl in combination with the geometry of the lift cylinder itself, the angle θ can be calculated from the values of a, b and L, the angle α can be calculated from the angles θ, β and γ, and the height H can be finally calculated from the angles α, lengths L1, H1 and R.

The height-adjusting oil cylinder can form a redundant mechanism of a height-collecting monitoring system with the existing swing angle sensor height-collecting measuring device, and continuous and reliable automatic work is ensured.

The height-adjusting oil cylinder has high integration level, good stability, almost no extra occupied space of the machine body, reliable safety protection measures of cables and outgoing line parts, adaptability to the use working condition of the coal mining machine, and capability of meeting the control requirements of wide range and high precision.

The axial and radial directions referred to herein refer to the axial and radial directions of the piston rod.

Claims

1. The utility model provides a stroke measurement pneumatic cylinder for coal-winning machine which characterized in that: the cylinder cover is fixed at the opening of one end of the cylinder barrel and seals the opening of the corresponding end, the cylinder cover is fixed at the opening of the other end of the cylinder barrel and seals the opening of the corresponding end, the cylinder barrel, the cylinder cover and the cylinder bottom form a cylinder body, the piston is sleeved and fixed on the piston rod, the piston is in sliding fit with the cylinder barrel in the cylinder barrel, the piston rod is a hollow piston rod, the magnetostrictive displacement sensor comprises a sensing electronic head, a measuring rod and a position magnet, the sensing electronic head is arranged in the cylinder bottom, the measuring rod and the position magnet are arranged in the piston rod, a retainer ring for a hole is further arranged in the piston rod to axially limit the position magnet, and the measuring rod stretches into a central hole of the piston rod and simultaneously penetrates through a central hole of the position magnet.

2. The stroke measurement hydraulic cylinder for a shearer of claim 1, wherein: the sensor comprises a cylinder bottom, and is characterized by further comprising an outgoing line transition sleeve and a connector, wherein the connector is provided with a bent aviation plug, an axial groove and a lateral groove which are communicated are formed in the cylinder bottom, the axial groove is opened at the inner side end face of the cylinder bottom, the lateral groove is opened at the outer cylindrical surface of the cylinder bottom, the sensor electronic head is fixedly arranged in the axial groove, the outgoing line transition sleeve is fixed on the outer cylindrical surface of the cylinder bottom through a top flange structure of the sensor electronic head, the other parts of the outgoing line transition sleeve are embedded in the lateral groove, a radial seal is arranged between the corresponding matching surfaces of the outgoing line transition sleeve and the cylinder bottom, the connector is fixedly arranged in an inner hole of the outgoing line transition sleeve, a radial seal is arranged between the corresponding matching surfaces of the connector and the outgoing line transition sleeve, one part of the bent aviation plug is positioned in the outgoing line transition sleeve, the other part of the bent aviation plug is positioned outside the cylinder bottom and extends along the outer cylindrical surface of the cylinder bottom, and a sensing wire of the magnetostrictive displacement sensor is electrically connected with the aviation plug through the connector after being led out from the sensor electronic head.

3. The stroke measurement hydraulic cylinder for a shearer as recited in claim 2, wherein: and the silica gel is filled in the residual space of the outlet transition sleeve after the connector is arranged in the inner hole of the outlet transition sleeve.

4. A shearer travel measurement hydraulic cylinder as claimed in claim 3, wherein: the protection seat is detachably and fixedly arranged on the outer cylindrical surface of the cylinder bottom and covers the notch of the lateral groove and the bent aviation plug, and the protection seat is provided with a wire outlet.

5. The stroke measurement hydraulic cylinder for a shearer of claim 4, wherein: the protection seat is formed by welding a quick connector and a protection cover, the quick connector serves as the wire outlet hole, and the wire outlet angle of the quick connector is 145 degrees.

6. The stroke measurement hydraulic cylinder for a shearer of claim 5, wherein: the quick connector is connected with a high-pressure rubber tube.

7. The stroke measurement hydraulic cylinder for a shearer of claim 6, wherein: the cylinder barrel extends in the front-back direction, the lateral groove is provided with an upper part and a lower part, two oil inlet and outlet ports are respectively arranged at the position, close to the left side or close to the right side, of the upper part and the lower part of the cylinder bottom, a balance valve installation position is arranged at the position, close to the right side or close to the left side, of the outer side of the cylinder bottom, when one of the two oil inlet and outlet ports at the upper part and the lower part is in a use state, a joint is arranged on the two oil inlet and outlet ports, and a plug is arranged on the other two oil inlet and outlet ports; when one of the lateral grooves is in a use state, a blank cap is arranged in the other lateral groove, and the corresponding protection seat is replaced by a temporary protection cover; the outer wall of the cylinder barrel is also welded with a section of oil duct, one end oil port of the oil duct is communicated with the rod cavity, the other end oil port is communicated with one oil inlet and outlet above and one oil inlet and outlet below through an oil hole arranged in the cylinder bottom, and the other oil inlet and outlet above and the other oil inlet and outlet below are communicated with the rodless cavity.

8. The stroke measurement hydraulic cylinder for a shearer of claim 7, wherein: a strip-shaped groove is arranged in the entity structure with the cylinder bottom facing outwards, a protection plate is arranged at the edge of a notch of the strip-shaped groove, and the strip-shaped groove and the protection plate enclose the balance valve installation position of the embedded protection structure.

9. The stroke measurement hydraulic cylinder for a shearer of claims 2, 3, 4, 5, 6, 7 or 8, wherein: the sensing electronic head is positioned in the axial groove through a positioning structure, the positioning structure comprises a mounting sleeve, a positioning screw, a locking screw and a sealing screw plug, the sensing electronic head is fixed in the mounting sleeve, the mounting sleeve is mounted in the axial groove, a radial limiting hole communicated with the axial groove is further formed in the cylinder bottom, the positioning screw, the sealing screw plug and the locking screw are sequentially connected in a threaded mode from inside to outside in the radial limiting hole, the head of the positioning screw is just embedded into the limiting groove positioned on the outer cylindrical surface of the mounting sleeve, and the outer side of the sealing screw plug abuts against the positioning screw.

10. The stroke measurement hydraulic cylinder for a shearer of claim 9, wherein: the installation sleeve comprises a base and a gland, wherein the base is an annular part, a positioning groove is formed in the base, the sensing electronic head is installed in the positioning groove, and the gland is fixed in a threaded hole of the base through threaded connection.