Mechanical arm type sampling device for testing coal sample
By designing a robotic arm sampling device, using hydraulically driven multi-link mechanism and lifting cylinder, the safety, automation, multi-point and multi-level collection of coal samples in the coal transport vehicle is achieved, solving the safety hazards and accuracy of traditional manual sampling. Low problems improve sampling accuracy and stability.
Patent Information
- Application Number
- CN202421100842.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-20
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-05-20
AI Technical Summary
During the research and testing of high-quality rock wool coke technology without adhesive, traditional manual sampling has problems of safety hazards and low sampling accuracy, and it is impossible to effectively collect coal samples in coal trucks in multi-point and multi-level areas.
A robotic arm sampling device is designed, including a fixed platform, a hydraulic station, a sampling mechanism and a collection frame. The automatic operation of the sampling components is achieved through hydraulically driven multi-link mechanism and lifting cylinder, which can be remotely operated, multi-point, and multi-level. Coal samples are collected to ensure sampling safety and accuracy.
It realizes safety, automation, multi-point and multi-level collection of coal samples in coal trucks, improves sampling accuracy and stability, and avoids safety hazards and low accuracy during manual sampling.
Smart Images
Figure CN222244821U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of sampling equipment, and in particular relates to a mechanical arm type sampling device for testing coal samples. Background Art
[0002] During the research and test of the technology of high-quality rock wool coke without binder, it is necessary to sample the transported coal for test coal. Traditional test coal sampling is done manually by samplers. Samplers need to climb on a sampling platform about 2 meters high and use a shovel to take samples in the coal truck. If the sampling process does not cooperate with the coal truck driver, the driver may accidentally drive during the sampling process, and the sampler may be taken off the platform and fall. If the coal truck is far away from the platform, the sampler needs to completely extend his upper body out of the guardrail to take samples, which poses a risk of human weightlessness and falling and injuring people. At the same time, manual sampling can only collect coal samples on the surface of the edge of the coal truck compartment, and it is impossible to collect multiple points in the entire compartment, nor can it collect deep coal samples, which easily leads to low accuracy of the test. Utility Model Content
[0003] The utility model overcomes the shortcomings of the prior art and provides a mechanical arm type sampling device for testing coal samples, thereby solving the problem of high risk and low accuracy caused by manual collection of coal samples on coal trucks.
[0004] In order to achieve the above purpose, the utility model is implemented through the following technical solutions.
[0005] A mechanical arm sampling device for testing coal samples comprises a fixed platform and a collecting rack. A hydraulic station and a sampling mechanism are arranged on the fixed platform. The sampling mechanism comprises a base, a support column, a first arm, a second arm, a first oil cylinder, a second oil cylinder, a lifting oil cylinder and a sampling tube. The base is rotatably arranged on the fixed platform, the support column is fixedly arranged on the base, the first arm is hinged on the support column, the second arm is hinged on the first arm, a first oil cylinder is arranged between the support column and the first arm, a second oil cylinder is arranged between the first arm and the second arm, the lifting oil cylinder is fixed on the second arm, a sampling assembly is arranged at the lower end of the lifting oil cylinder, the collecting rack is arranged on one side of the fixed platform, and a removable collecting bucket is arranged inside the collecting rack.
[0006] Furthermore, the base and the upper end surface of the fixed platform are rotatably connected via a slewing bearing; a slewing cylinder is arranged at the upper end surface of the fixed platform, the slewing cylinder is arranged horizontally, one end of the cylinder bottom of the slewing cylinder is hinged to the hinge seat at the upper end surface of the fixed platform, and one end of the piston rod of the slewing cylinder is hinged to the upper end surface of the base; the hinge axes at both ends of the slewing cylinder are kept vertical.
[0007] Furthermore, the first arm is arranged on the front side of the support column, and the rear end of the first arm is hinged to the hinge seat at the lower end of the front end surface of the support column through a pin shaft; two left-right symmetrical first connecting rods are arranged below the first arm, and the rear end of the first connecting rods is hinged to the hinge seat at the lower end of the front end surface of the support column through a pin shaft; two left-right symmetrical first vertical plates are arranged on both sides of the front end of the first arm, and the front end of the first arm is respectively hinged to the upper ends of the two first vertical plates; the front ends of the two first connecting rods are respectively hinged to the lower ends of the first vertical plates on the same side.
[0008] Furthermore, the hinge axis at the rear end of the first connecting rod is located directly below the hinge axis at the rear end of the first arm, the hinge axis at the front end of the first connecting rod is located directly below the hinge axis at the front end of the first arm, and the distance between the intersection axis at the rear end of the first connecting rod and the hinge axis at the rear end of the first arm is equal to the distance between the hinge axis at the front end of the first connecting rod and the hinge axis at the front end of the first arm.
[0009] Furthermore, the second arm is arranged on the front side of the first arm, and the rear end of the second arm is hinged to the front ends of the two first connecting rods through a pin shaft; two left-right symmetrical second connecting rods are arranged above the second arm, and the rear ends of the two second connecting rods are hinged to the front ends of the first connecting rods through a pin shaft; two left-right symmetrical second vertical plates are arranged on both sides of the front end of the second arm, and the front end of the second arm is respectively hinged to the lower ends of the two second vertical plates; the front ends of the two second connecting rods are respectively hinged to the upper ends of the second vertical plates on the same side.
[0010] Furthermore, the hinge axis at the front end of the second connecting rod is located directly above the hinge axis at the front end of the second support arm, and the distance between the hinge axis at the front end of the second connecting rod and the hinge axis at the front end of the second support arm is equal to the distance between the hinge axis at the front end of the first connecting rod and the hinge axis at the front end of the first support arm.
[0011] Furthermore, one end of the cylinder bottom of the first cylinder is hinged to the hinge seat at the upper end of the support column, one end of the piston rod of the first cylinder is hinged to the hinge seat in the middle of the first support arm, and the hinge axes at both ends of the first cylinder are horizontally arranged along the left and right directions; one end of the cylinder bottom of the second cylinder is hinged to the hinge seat in the middle of the first connecting rod, one end of the piston rod of the second cylinder is hinged to the hinge seat in the middle of the second support arm, and the hinge axes at both ends of the second cylinder are horizontally arranged along the left and right directions.
[0012] Furthermore, a mounting seat is fixedly arranged at the front end of the second vertical plate, and the cylinder body of the lifting cylinder is fixedly arranged on the mounting seat, and one end of the piston rod of the lifting cylinder is vertically downward.
[0013] Furthermore, the sampling assembly includes a sampling motor, a sampling tube, a sampling rod, and a sampling cutter head; the sampling motor is fixedly arranged at the lower end of the piston rod of the lifting cylinder, the output shaft of the sampling motor is vertically downward, and a vertical sampling rod is fixedly arranged on the output shaft of the sampling motor; a vertical sampling tube is sleeved on the outer side of the sampling rod, the upper and lower ends of the sampling tube remain open, and the upper end of the sampling tube is fixedly connected to the outer casing of the sampling motor through a circle of vertical rods in a circular array; a spiral sampling cutter head is fixedly arranged at the lower end of the sampling rod, and the sampling cutter head is located inside the lower end opening of the sampling tube.
[0014] Furthermore, the collecting rack is arranged on the ground on one side of the fixed platform, and a trumpet-shaped collecting funnel which is thick at the top and thin at the bottom is fixedly arranged at the upper end of the collecting rack, and a placing plate is fixedly arranged in the middle of the inner side of the collecting rack, and the placing plate is used to hold the collecting bucket; when the collecting bucket is placed on the upper end of the placing plate, the collecting bucket is located below the lower end outlet of the collecting funnel.
[0015] The beneficial effects of the utility model compared with the prior art are:
[0016] (1) The utility model provides a mechanical arm sampling device for testing coal samples. The coal samples on the coal truck are collected by the automatically operated sampling device. There is no need to manually climb to a high platform for sampling. The operator can realize remote control from a distance, thereby ensuring the safety of personnel during sampling.
[0017] (2) The utility model provides a mechanical arm type sampling device for testing coal samples. The mechanical arm type sampling device is fixed on a platform, and the sampling device is driven by an oil cylinder to move as a whole, so that the sampling component can be moved to any position of the coal truck compartment, so that coal samples at different positions in the compartment can be collected; a lifting cylinder is provided to drive the sampling component to descend vertically, so that coal samples deep in the compartment can be collected; through the coordination of the above-mentioned processes, the coal samples in the compartment can be collected at multiple levels and multiple points, avoiding the randomness during sampling, and thus ensuring that the accuracy of the final test meets the requirements.
[0018] (3) The utility model provides a mechanical arm sampling device for testing coal samples. Through two sets of parallelogram four-bar mechanisms, the sampling assembly is always kept at a vertical downward angle. In this way, when collecting coal samples, the sampling tube will not deviate from the angle even during the descent process, thereby ensuring that the sampling tube can collect coal samples at different depths at the same point, thereby improving the stability during sampling. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The utility model is further described in detail below in conjunction with the accompanying drawings:
[0020] Figure 1It is a three-dimensional schematic diagram of the utility model as a whole Figure 1 ;
[0021] Figure 2 It is a three-dimensional schematic diagram of the utility model as a whole Figure 2 ;
[0022] Figure 3 It is a side view of the utility model as a whole;
[0023] Figure 4 yes Figure 3 Schematic diagram of the structure of the sampling mechanism;
[0024] Figure 5 It is a three-dimensional schematic diagram of the sampling mechanism;
[0025] Figure 6 It is a three-dimensional schematic diagram of the components after the sampling tube is cut in half;
[0026] Figure 7 It is a three-dimensional schematic diagram of a collection rack;
[0027] Among them, 1 is a fixed platform, 2 is a collecting rack, 3 is a hydraulic station, 4 is a base, 5 is a supporting column, 6 is a first arm, 7 is a second arm, 8 is a first cylinder, 9 is a second cylinder, 10 is a lifting cylinder, 11 is a sampling assembly, 12 is a fixed plate, 13 is a supporting leg, 14 is a connecting rod, 15 is a ladder, 16 is a rotary cylinder, 17 is a first connecting rod, 18 is a first vertical plate, 19 is a second connecting rod, 20 is a second vertical plate, 21 is a mounting seat, 22 is a sampling motor, 23 is a sampling rod, 24 is a sampling tube, 25 is a sampling knife head, 26 is a collecting funnel, and 27 is a placement plate. DETAILED DESCRIPTION
[0028] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail in combination with the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. The technical solution of the present invention is described in detail below in combination with the embodiments and the accompanying drawings, but the scope of protection is not limited thereto.
[0029] like Figure 1As shown in FIG. 7 , the utility model provides a mechanical arm sampling device for testing coal samples, comprising a fixed platform 1 and a collecting frame 2, a hydraulic station 3 and a sampling mechanism are arranged on the fixed platform 1, the sampling mechanism comprises a base 4, a support column 5, a first arm 6, a second arm 7, a first oil cylinder 8, a second oil cylinder 9, a lifting oil cylinder 10, and a sampling tube 24, the base 4 is rotatably arranged on the fixed platform 1, the support column 5 is fixedly arranged on the base 4, the first arm 6 is hinged on the support column 5, the second arm 7 is hinged on the first arm 6, the first oil cylinder 8 is arranged between the support column 5 and the first arm 6, the second oil cylinder 9 is arranged between the first arm 6 and the second arm 7, the lifting oil cylinder 10 is fixed on the second arm 7, the lower end of the lifting oil cylinder 10 is arranged with a sampling assembly 11, the collecting frame 2 is arranged on one side of the fixed platform 1, and a removable collecting bucket is arranged inside the collecting frame 2.
[0030] The fixed platform 1 comprises a horizontally arranged square fixed plate 12, a vertical support leg 13 is fixedly arranged at each of the four corners of the lower end surface of the fixed plate 12, and a horizontal connecting rod 14 is fixedly arranged between the middle parts of two adjacent support legs 13. A ladder 15 is arranged on one side of the fixed platform 1, and the upper end of the fixed platform 1 can be reached from the ground through the ladder 15.
[0031] The base 4 is a circular plate-like structure arranged horizontally. The base 4 is arranged above the fixed platform 1. The base 4 is rotatably connected to the upper end surface of the fixed platform 1 through a slewing bearing. A slewing cylinder 16 is arranged at the upper end surface of the fixed platform 1. The slewing cylinder 16 is arranged horizontally. One end of the cylinder bottom of the slewing cylinder 16 is hinged to the hinge seat at the upper end surface of the fixed platform 1. One end of the piston rod of the slewing cylinder 16 is hinged to the upper end surface of the base 4. The hinge axes at both ends of the slewing cylinder 16 are kept vertical. The base 4 is controlled to rotate on the upper end of the fixed platform 1 by extending and retracting the piston rod of the slewing cylinder 16.
[0032] The support column 5 is a vertically arranged square columnar structure, and the lower end of the support column 5 is fixedly arranged at the center of the upper end surface of the base 4.
[0033] The first arm 6 is arranged at the front side of the support column 5. The front end height of the first arm 6 is higher than the rear end height of the first arm 6. The rear end of the first arm 6 is hinged to the hinge seat at the lower end of the front end surface of the support column 5 through a pin. Two left-right symmetrical first connecting rods 17 are arranged below the first arm 6. The front end height of the first connecting rod 17 is higher than the rear end height of the first connecting rod 17. The rear end of the first connecting rod 17 is hinged to the hinge seat at the lower end of the front end surface of the support column 5 through a pin. Two left-right symmetrical first vertical plates 18 are arranged on both sides of the front end of the first arm 6. The first vertical plates 18 remain vertical. The front end of the first arm 6 is hinged to the upper ends of the two first vertical plates 18 respectively. The front ends of the two first connecting rods 17 are hinged to the lower ends of the first vertical plates 18 on the same side respectively.
[0034] The hinge axis at the rear end of the first link 17 is located directly below the hinge axis at the rear end of the first arm 6, the hinge axis at the front end of the first link 17 is located directly below the hinge axis at the front end of the first arm 6, and the distance between the intersection axis at the rear end of the first link 17 and the hinge axis at the rear end of the first arm 6 is equal to the distance between the hinge axis at the front end of the first link 17 and the hinge axis at the front end of the first arm 6.
[0035] The second arm 7 is arranged at the front side of the first arm 6, and the front end height of the second arm 7 is lower than the rear end height of the second arm 7. The rear end of the second arm 7 is hinged to the front ends of the two first connecting rods 17 through a pin. Two left-right symmetrical second connecting rods 19 are arranged above the second arm 7, and the front end height of the second connecting rod 19 is lower than the rear end height of the second connecting rod 19, and the rear ends of the two second connecting rods 19 are hinged to the front end of the first connecting rod 17 through a pin. Two left-right symmetrical second vertical plates 20 are arranged on both sides of the front end of the second arm 7, and the second vertical plates 20 remain vertical, and the front end of the second arm 7 is hinged to the lower ends of the two second vertical plates 20 respectively. The front ends of the two second connecting rods 19 are hinged to the upper ends of the second vertical plates 20 on the same side respectively.
[0036] The hinge axis at the front end of the second connecting rod 19 is located directly above the hinge axis at the front end of the second support arm 7, and the distance between the hinge axis at the front end of the second connecting rod 19 and the hinge axis at the front end of the second support arm 7 is equal to the distance between the hinge axis at the front end of the first connecting rod 17 and the hinge axis at the front end of the first support arm 6.
[0037] The first arm 6 and the first connecting rod 17 are both "︿"-shaped rod structures, that is, the middle parts of the first arm 6 and the first connecting rod 17 protrude toward the upper rear side, and the first arm 6 and the first connecting rod 17 include two sections that form an obtuse angle with each other.
[0038] One end of the cylinder bottom of the first oil cylinder 8 is hinged to the hinge seat at the upper end of the support column 5, one end of the piston rod of the first oil cylinder 8 is hinged to the hinge seat in the middle of the first support arm 6, and the hinge axes at both ends of the first oil cylinder 8 are horizontally arranged along the left and right directions.
[0039] One end of the cylinder bottom of the second oil cylinder 9 is hinged to the hinge seat in the middle of the first connecting rod 17, one end of the piston rod of the second oil cylinder 9 is hinged to the hinge seat in the middle of the second support arm 7, and the hinge axes at both ends of the second oil cylinder 9 are horizontally arranged along the left and right directions.
[0040] A mounting seat 21 is fixedly disposed at the front end of the second vertical plate 20 , and the cylinder body of the lifting cylinder 10 is fixedly disposed on the mounting seat 21 , with one end of the piston rod of the lifting cylinder 10 pointing vertically downward.
[0041] The sampling assembly 11 includes a sampling motor 22, a sampling tube 24, a sampling rod 23, and a sampling cutter head 25. The sampling motor 22 is fixedly arranged at the lower end of the piston rod of the lifting cylinder 10, the output shaft of the sampling motor 22 is vertically downward, and a vertical sampling rod 23 is fixedly arranged on the output shaft of the sampling motor 22. A vertical sampling tube 24 is sleeved on the outer side of the sampling rod 23, the upper and lower ends of the sampling tube 24 remain open, and the upper end of the sampling tube 24 is fixedly connected to the outer shell of the sampling motor 22 through a circle of vertical rods in a circular array. A spiral sampling cutter head 25 is fixedly arranged at the lower end of the sampling rod 23, and the sampling cutter head 25 is located inside the lower end opening of the sampling tube 24.
[0042] The rotary cylinder 16 , the first cylinder 8 , the second cylinder 9 , and the lifting cylinder 10 are all connected to the hydraulic station 3 via hydraulic pipelines.
[0043] The collecting rack 2 is arranged on the ground at one side of the fixed platform 1. A trumpet-shaped collecting funnel 26 with a thick top and a thin bottom is fixedly arranged at the upper end of the collecting rack 2. A placing plate 27 is fixedly arranged at the middle of the inner side of the collecting rack 2. The placing plate 27 is used to hold the collecting bucket. When the collecting bucket is placed on the upper end of the placing plate 27, the collecting bucket is located below the lower end outlet of the collecting funnel 26.
[0044] The working principle of the utility model is:
[0045] When the coal truck arrives at the sampling workshop, the coal truck is driven to one side of the fixed platform 1, and the tarpaulin of the coal truck is opened to expose the transported coal.
[0046] The piston rod of the rotary oil cylinder 16 is extended and retracted to drive the base 4 to rotate, so that the sampling mechanism is rotated as a whole, ensuring that the sampling assembly 11 is located above the bucket of the coal truck.
[0047] By controlling the extension and retraction of the piston rods of the first oil cylinder 8 and the second oil cylinder 9, the angles of the first arm 6 and the second arm 7 are adjusted, so that the lifting assembly moves to the position above the coal sample collection position. Since the support column 5, the first connecting rod 17, the first arm 6, and the first vertical plate 18 form a parallelogram structure, the first arm 6 keeps the first vertical plate 18 in a vertical state when rotating; since the first vertical plate 18, the second arm 7, the second connecting rod 19, and the second vertical plate 20 form a parallelogram structure, the second arm 7 keeps the second vertical plate 20 in a vertical state when rotating, thereby keeping the lifting oil cylinder 10 and the sampling assembly 11 in a vertical state.
[0048] When the position of the sampling assembly 11 is determined, the piston rod of the lifting cylinder 10 is controlled to extend, and the sampling motor 22 is controlled to start rotating. The sampling motor 22 drives the sampling cutter head 25 to rotate inside the lower opening of the sampling tube 24 through the sampling rod 23. After the lower end of the sampling tube 24 contacts the coal on the coal truck, the spiral sampling cutter head 25 continuously collects coal samples into the sampling tube 24. The sampling assembly 11 gradually descends while continuously collecting, so that the lower end of the sampling tube 24 continues to penetrate deep into the interior of the transported coal, so that the coal samples inside the transported coal can also be collected. Thus, the coal samples inside the sampling tube 24 or at different depths are finally collected.
[0049] When the sampling is completed, the sampling motor 22 stops rotating, and the piston rod of the lifting cylinder 10 is gradually retracted, thereby driving the sampling assembly 11 to continuously rise, and the sampling tube 24 is gradually pulled out of the coal in the bucket of the coal truck.
[0050] When the sampling tube 24 is completely pulled out, the piston rod of the rotary cylinder 16 is extended and retracted to drive the base 4 to rotate, so that the sampling mechanism rotates as a whole, ensuring that the sampling assembly 11 moves to the side of the collecting funnel 26. Then, by controlling the extension and retraction of the piston rods of the first cylinder 8 and the second cylinder 9, the angles of the first arm 6 and the second arm 7 are adjusted, so that the lifting assembly moves above the collecting funnel 26. Then, the piston rod of the lifting cylinder 10 is controlled to extend, and the sampling tube 24 gradually descends until the lower end opening of the sampling tube 24 is located inside the upper end opening of the collecting funnel 26. At this time, the sampling motor 22 is controlled to rotate in the opposite direction, so that the coal sample continuously slides from the sampling tube 24 into the collecting funnel 26, and finally enters the collecting barrel through the collecting funnel 26.
[0051] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.
Claims
1. A mechanical arm sampling device for testing coal samples, characterized in that: The invention comprises a fixed platform (1) and a collecting frame (2), wherein a hydraulic station (3) and a sampling mechanism are arranged on the fixed platform (1), wherein the sampling mechanism comprises a base (4), a supporting column (5), a first supporting arm (6), a second supporting arm (7), a first oil cylinder (8), a second oil cylinder (9), a lifting oil cylinder (10), and a sampling tube (24), wherein the base (4) is rotatably arranged on the fixed platform (1), the supporting column (5) is fixedly arranged on the base (4), and the first supporting arm (6) is hinged to the supporting column (5). The second support arm (7) is hinged on the first support arm (6), a first oil cylinder (8) is arranged between the support column (5) and the first support arm (6), a second oil cylinder (9) is arranged between the first support arm (6) and the second support arm (7), a lifting oil cylinder (10) is fixed on the second support arm (7), a sampling assembly (11) is arranged at the lower end of the lifting oil cylinder (10), a collecting rack (2) is arranged on one side of the fixed platform (1), and a removable collecting bucket is arranged inside the collecting rack (2).
2. A mechanical arm sampling device for testing coal samples according to claim 1, characterized in that: The base (4) is rotatably connected to the upper end surface of the fixed platform (1) via a slewing bearing; a slewing cylinder (16) is arranged at the upper end surface of the fixed platform (1); the slewing cylinder (16) is arranged horizontally; one end of the cylinder bottom of the slewing cylinder (16) is hinged to a hinge seat at the upper end surface of the fixed platform (1); one end of the piston rod of the slewing cylinder (16) is hinged to the upper end surface of the base (4); and the hinge axes at both ends of the slewing cylinder (16) are kept vertical.
3. A mechanical arm sampling device for testing coal samples according to claim 1, characterized in that: The first support arm (6) is arranged at the front side of the support column (5), and the rear end of the first support arm (6) is hinged to the hinge seat at the lower end of the front end surface of the support column (5) through a pin shaft; two left-right symmetrical first connecting rods (17) are arranged below the first support arm (6), and the rear end of the first connecting rod (17) is hinged to the hinge seat at the lower end of the front end surface of the support column (5) through a pin shaft; two left-right symmetrical first vertical plates (18) are arranged on both sides of the front end of the first support arm (6), and the front end of the first support arm (6) is respectively hinged to the upper ends of the two first vertical plates (18); the front ends of the two first connecting rods (17) are respectively hinged to the lower ends of the first vertical plates (18) on the same side.
4. A mechanical arm sampling device for testing coal samples according to claim 3, characterized in that: The hinge axis at the rear end of the first connecting rod (17) is located directly below the hinge axis at the rear end of the first supporting arm (6), the hinge axis at the front end of the first connecting rod (17) is located directly below the hinge axis at the front end of the first supporting arm (6), and the distance between the intersection axis at the rear end of the first connecting rod (17) and the hinge axis at the rear end of the first supporting arm (6) is equal to the distance between the hinge axis at the front end of the first connecting rod (17) and the hinge axis at the front end of the first supporting arm (6).
5. A mechanical arm type sampling device for testing coal samples according to claim 4, characterized in that: The second support arm (7) is arranged at the front side of the first support arm (6), and the rear end of the second support arm (7) is hinged to the front ends of the two first connecting rods (17) through a pin shaft; two left-right symmetrical second connecting rods (19) are arranged above the second support arm (7), and the rear ends of the two second connecting rods (19) are hinged to the front ends of the first connecting rods (17) through a pin shaft; two left-right symmetrical second vertical plates (20) are arranged on both sides of the front end of the second support arm (7), and the front end of the second support arm (7) is respectively hinged to the lower ends of the two second vertical plates (20); the front ends of the two second connecting rods (19) are respectively hinged to the upper ends of the second vertical plates (20) on the same side.
6. A mechanical arm type sampling device for testing coal samples according to claim 5, characterized in that: The hinge axis at the front end of the second connecting rod (19) is located directly above the hinge axis at the front end of the second supporting arm (7), and the distance between the hinge axis at the front end of the second connecting rod (19) and the hinge axis at the front end of the second supporting arm (7) is equal to the distance between the hinge axis at the front end of the first connecting rod (17) and the hinge axis at the front end of the first supporting arm (6).
7. A mechanical arm sampling device for testing coal samples according to claim 6, characterized in that: One end of the cylinder bottom of the first oil cylinder (8) is hinged to the hinge seat at the upper end of the support column (5), one end of the piston rod of the first oil cylinder (8) is hinged to the hinge seat in the middle of the first support arm (6), and the hinge axes at both ends of the first oil cylinder (8) are arranged horizontally along the left-right direction; one end of the cylinder bottom of the second oil cylinder (9) is hinged to the hinge seat in the middle of the first connecting rod (17), one end of the piston rod of the second oil cylinder (9) is hinged to the hinge seat in the middle of the second support arm (7), and the hinge axes at both ends of the second oil cylinder (9) are arranged horizontally along the left-right direction.
8. The mechanical arm sampling device for testing coal samples according to claim 5, characterized in that: A mounting seat (21) is fixedly arranged at the front end of the second vertical plate (20), the cylinder body of the lifting cylinder (10) is fixedly arranged on the mounting seat (21), and one end of the piston rod of the lifting cylinder (10) is vertically downward.
9. A mechanical arm type sampling device for testing coal samples according to claim 1, characterized in that: The sampling assembly (11) comprises a sampling motor (22), a sampling tube (24), a sampling rod (23), and a sampling blade (25); the sampling motor (22) is fixedly arranged at the lower end of the piston rod of the lifting cylinder (10), the output shaft of the sampling motor (22) is vertically downward, and a vertical sampling rod (23) is fixedly arranged on the output shaft of the sampling motor (22); a vertical sampling tube (24) is sleeved on the outer side of the sampling rod (23), the upper and lower ends of the sampling tube (24) remain open, and the upper end of the sampling tube (24) is fixedly connected to the outer shell of the sampling motor (22) through a circle of vertical rods in a circular array; a spiral sampling blade (25) is fixedly arranged at the lower end of the sampling rod (23), and the sampling blade (25) is located inside the lower end opening of the sampling tube (24).
10. A mechanical arm sampling device for testing coal samples according to claim 1, characterized in that: The collecting rack (2) is arranged on the ground on one side of the fixed platform (1); a trumpet-shaped collecting funnel (26) which is thick at the top and thin at the bottom is fixedly arranged at the upper end of the collecting rack (2); a placement plate (27) is fixedly arranged at the middle of the inner side of the collecting rack (2); the placement plate (27) is used to hold the collecting bucket; when the collecting bucket is placed on the upper end of the placement plate (27), the collecting bucket is located below the lower end outlet of the collecting funnel (26).