Mine hoist emergency braking friction pair temperature rise suppression system and control method

Abstract

The invention discloses a mine hoist emergency braking friction pair temperature rise restraining system which comprises a brake disc cooling assembly, a cooling rotor assembly and a cooling hydraulic system. The brake disc cooling assembly is composed of a brake disc, a cooling disc and a connecting frame, the cooling disc is embedded into an inner cavity of the brake disc, a closed annular flow channel is formed in the cooling disc and the brake disc, and the connecting frame and the cooling disc are provided with a liquid inlet hole and a liquid outlet hole correspondingly in the radial direction. The cooling rotor assembly comprises a cooling rotor and a cooling rotor shell, a liquid inlet flow channel and a liquid outlet flow channel in the cooling rotor are connected with the liquid inlet hole and the liquid outlet hole of the connecting frame through pipelines respectively, and an inner cavity of the cooling rotor shell is provided with annular flow channels communicated with the liquid inlet flow channel and the liquid outlet flow channel in the cooling rotor respectively; the cooling hydraulic system is used for providing cooling liquid into the closed annular flow channel. The invention further discloses a friction pair temperature rise control method based on the system, temperature rise of the friction pair can be effectively restrained in the emergency braking process of the mine hoist, and braking safety is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of mine hoist braking, and in particular to an emergency braking friction pair temperature rise suppression system and control method for a mine hoist. Background Art

[0002] As a key transportation equipment in coal production, a mine hoist undertakes key tasks such as ore hoisting, personnel transportation, material transportation, and safety guarantee. The mine hoist transports the mined coal to the ground through a cage or a skip, and at the same time transports personnel, equipment, and support materials. The operating efficiency of the hoist directly affects the mine production capacity, and the reliability of its braking system is directly related to the life safety and production efficiency of underground personnel. As the core safety guarantee unit of the mine hoist, the braking system needs to quickly respond and stably output braking torque under emergency braking conditions. When the hoist performs emergency braking, a hydraulic or spring mechanism pushes the brake caliper to clamp the rotating brake disc, and the mechanical energy is converted into heat energy through the friction force between the friction pair (brake disc and brake shoe), so as to realize the emergency braking of the mine hoist. However, since the mine hoist often operates under high-speed and heavy-load conditions, if a large amount of heat generated between the brake disc and the brake shoe friction pair during the emergency braking process cannot be dissipated in time, it will cause the temperature of the brake disc to rise sharply, leading to thermal degradation of the material and a sharp drop in the friction coefficient, and then resulting in a decline in the braking force, which is extremely likely to cause insufficient braking force and induce braking safety accidents, seriously threatening the operating safety of the mine hoist. However, there is still a lack of effective methods to effectively suppress the temperature rise of the friction pair during the emergency braking process of mine hoists at home and abroad. Therefore, it is urgent to invent a method that can effectively suppress the temperature rise of the friction pair during the emergency braking process of mine hoists to break through the bottleneck of the existing technology and ensure the braking safety and reliability of mine hoists under high-speed and heavy-load emergency braking conditions. Summary of the Invention

[0003] In order to overcome the defects in the prior art, the present invention provides an emergency braking friction pair temperature rise suppression system and control method for a mine hoist.

[0004] The technical solution adopted by the present invention:

[0005] In a first aspect, the present invention proposes an emergency braking friction pair temperature rise suppression system for a mine hoist, including: a brake disc cooling assembly, a cooling rotor assembly, and a cooling hydraulic system.

[0006] The brake disc cooling assembly includes a brake disc, a cooling disc, and a connecting frame. The brake disc adopts an annular sheet structure with a hollow interior. The cooling disc is a complete ring formed by circumferentially splicing a number of brake cooling blocks. The cooling disc is embedded in the inner cavity of the brake disc. A sealed annular flow channel is formed between the side surface of the cooling disc and the interior of the brake disc through an annular sealing ring. The connecting frame is in the shape of a cylindrical boss with a hollow interior. The connecting frame is sleeved in the annular hole of the brake disc. Corresponding liquid inlet holes and liquid outlet holes are respectively arranged in the radial direction of the connecting frame and the cooling disc. One end of the connecting frame is fixed to the hoist drum;

[0007] The cooling rotor assembly includes a cooling rotor and a cooling rotor housing. The cooling rotor is a solid cylinder. An inlet liquid flow channel and an outlet liquid flow channel are arranged inside the cooling rotor. The inlet liquid flow channel and the outlet liquid flow channel inside the cooling rotor are respectively connected to the liquid inlet hole and the liquid outlet hole of the connecting frame through pipelines. One end of the cooling rotor is fixed in the annular hole at the other end of the connecting frame opposite to the hoist drum. The other end of the cooling rotor is sleeved in the inner cavity of the cooling rotor housing. Two annular flow channels respectively communicating with the inlet liquid flow channel and the outlet liquid flow channel inside the cooling rotor are arranged in the inner cavity of the cooling rotor housing. A coolant inlet and a coolant outlet corresponding to the internal annular flow channel are arranged on the surface of the cooling rotor housing. The cooling rotor housing is fixed to the hoist frame;

[0008] The cooling hydraulic system includes a liquid storage tank, a hydraulic pump, a switch valve, a coolant proportional flow valve, an overflow valve, and an oil suction filter. The hydraulic pump is connected to the coolant proportional flow valve through a pipeline via the switch valve. The coolant proportional flow valve is connected to the coolant inlet on the cooling rotor housing through a pipeline. One end of the overflow valve is connected in parallel to the hydraulic pump, and the other end is connected to the liquid storage tank. The oil suction filter is connected to the hydraulic pump through a pipeline to the liquid storage tank. The coolant outlet on the cooling rotor housing is connected to the liquid storage tank through a pipeline. A return liquid temperature sensor is installed at the coolant outlet on the cooling rotor housing.

[0009] Preferably, the connection between the connecting frame and the brake disc adopts a circumferential bolt connection method.

[0010] Preferably, the connection between the connecting frame and the hoist drum adopts a welding method.

[0011] Preferably, the number of brake cooling blocks used for the cooling disc is 4 - 6.

[0012] Preferably, the liquid inlet hole and the liquid outlet hole on the connecting frame are on the same straight line.

[0013] Preferably, the number of annular sealing rings between the side surface of the cooling disc and the brake disc is 2 - 4.

[0014] Preferably, 1 - 2 annular sealing structures are respectively adopted on both sides of the annular oil channel in the inner cavity of the cooling rotor housing.

[0015] Second aspect, the present invention also proposes a method for controlling the temperature rise of the emergency braking friction pair of a mine hoist, including the following steps:

[0016] Step S1: Collect the current temperature T of the brake disc through a return liquid temperature sensor, and at the same time collect the current braking force F and the current operating speed v of the hoist;

[0017] Step S2: When a braking signal is received, different calculation formulas are selected to calculate the theoretical output flow rate Q according to the different current temperatures T of the brake disc collected, specifically as follows: out , specifically as follows:

[0018] If T < T0, then Q out = 0,

[0019] If T0 ≤ T < T1, then

[0020] If T ≥ T1, then

[0021] Where: T0 is the trigger temperature threshold, T1 is the cooling mode switching threshold, T max is the maximum working temperature of the brake disc, Q max is the maximum output flow rate of the coolant proportion flow valve, Q base is the basic output flow rate, k T is the temperature error gain coefficient, k Fv is the braking power gain coefficient, F max is the maximum braking force, v max is the maximum hoisting speed of the hoist.

[0022] Step S3: Calculate the final output flow rate Q final of the coolant proportion flow valve, and the specific formula is as follows:

[0023]

[0024] Step S4: Convert the obtained Q final into a voltage control signal and output it to the coolant proportion flow valve to control the opening of the valve core of the coolant proportion flow valve and then change the coolant flow rate, and repeat the above steps S1 to S4.

[0025] Preferably, the value range of the basic output flow rate Q base is Q base = (0.1 - 0.3)Q max , and the value range of the temperature error gain coefficient k T is k T = 0.1 - 0.5, and the value range of the braking power gain coefficient k Fv is k Fv = 0.4 - 0.6.

[0026] Preferably, the value range of the triggering temperature threshold T0 is T0 = 0.1 - 0.3T max , and the value range of the cooling mode switching threshold T1 is T1 = (2 - 3)T0, and the maximum operating temperature T of the brake disc max has a value range of T max = 250 - 300 °C.

[0027] The beneficial effects of the present invention are as follows:

[0028] (1) The system for suppressing the temperature rise of the emergency braking friction pair of the mine hoist of the present invention can provide cooling liquid during the emergency braking process of the mine hoist, effectively reducing the heat generated during the emergency braking of the mine hoist, suppressing the surface temperature of the braking friction pair, and reducing the thermal deformation of the brake disc and the thermal attenuation of the friction coefficient;

[0029] (2) In the system for suppressing the temperature rise of the emergency braking friction pair of the mine hoist of the present invention, the cooling liquid can circulate in the annular flow channel between the brake disc and the cooling disc, effectively increasing the contact area between the cooling liquid and the brake disc and improving the effect of suppressing the temperature rise;

[0030] (3) In the system for suppressing the temperature rise of the emergency braking friction pair of the mine hoist of the present invention, the cooling liquid is input into the brake disc through the annular channel between the cooling rotor housing and the cooling rotor and the flow channel inside the cooling rotor, and can effectively circulate when the brake disc rotates without affecting the rotation of the drum and the brake disc of the mine hoist;

[0031] (4) The method for controlling the temperature rise of the emergency braking friction pair of the mine hoist of the present invention, according to the real-time temperature of the brake disc and the temperature error during braking, introduces a temperature error gain coefficient to adjust the control voltage of the cooling liquid proportional flow valve and control the cooling liquid flow rate. And when the temperature exceeds a certain range, based on the real-time temperature of the brake disc and the temperature error, the braking force of the hoist, the running speed of the hoist, and the braking power are considered, and a braking power gain coefficient is introduced to adjust the control voltage of the cooling liquid proportional flow valve and control the cooling liquid flow rate, which can effectively suppress the temperature rise of the emergency braking friction pair of the hoist under different working conditions. Description of the Drawings

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Figure 1 is the overall framework schematic diagram of the system for suppressing the temperature rise of the emergency braking friction pair of the mine hoist of the present invention;

[0034] Figure 2 is the axial sectional view of the assembly of the brake disc cooling assembly and the cooling rotor assembly of the present invention;

[0035] Figure 3Cross-sectional view of the cooling rotor housing of the present invention;

[0036] Figure 4 Temperature rise control flowchart of the emergency braking friction pair of the mine hoist of the present invention;

[0037] In the figure: 1 - Brake disc cooling assembly; 11 - Brake disc; 12 - Cooling disc; 13 - Connecting frame; 2 - Cooling rotor assembly; 21 - Cooling rotor; 22 - Cooling rotor housing; 3 - Cooling hydraulic system; 31 - Liquid storage tank; 32 - Hydraulic pump; 33 - Switch valve; 34 - Coolant proportional flow valve; 35 - Relief valve; 36 - Suction oil filter; 37 - Return liquid temperature sensor. Detailed implementation manner

[0038] As Figures 1 - 3 shown, a temperature rise suppression system for the emergency braking friction pair of a mine hoist is used for suppressing the temperature rise of the emergency braking friction pair of the mine hoist, and includes: a brake disc cooling assembly 1, a cooling rotor assembly 2, and a cooling hydraulic system 3.

[0039] The brake disc cooling assembly 1 includes a brake disc 11, a cooling disc 12, and a connecting frame 13. The brake disc 11 adopts an internally hollow annular sheet structure. The cooling disc 12 is a complete ring formed by circumferentially splicing 4 brake cooling blocks. The cooling disc 12 is embedded in the inner cavity of the brake disc 11. The side surface of the cooling disc 12 forms a sealed annular flow channel with the inside of the brake disc 11 through 4 annular sealing rings, which is used to increase the contact area between the coolant and the brake disc. The connecting frame 13 is in the shape of a hollow cylindrical boss. The connecting frame 13 is sleeved in the annular hole of the brake disc 11. The connecting frame 13 and the cooling disc 12 are respectively provided with corresponding liquid inlet holes and liquid outlet holes in the radial direction. The liquid inlet hole and the liquid outlet hole on the connecting frame 13 are on the same straight line. The connection between the connecting frame 13 and the brake disc 11 adopts a circumferential bolt connection method. One end of the connecting frame 13 is fixed to the hoist drum by welding.

[0040] The described cooling rotor assembly 2 includes a cooling rotor 21 and a cooling rotor housing 22. The cooling rotor 21 is a solid cylinder. An inlet liquid flow channel and an outlet liquid flow channel are arranged inside the cooling rotor 21. The inlet liquid flow channel and the outlet liquid flow channel inside the cooling rotor 21 are respectively connected to the inlet hole and the outlet hole of the connecting frame 13 through pipelines. One end of the cooling rotor 21 is fixed in the annular hole at the other end of the connecting frame 13 opposite to the hoist drum. The other end of the cooling rotor 21 is sleeved in the inner cavity of the cooling rotor housing 22. Two bearings are sleeved in the inner cavities at both ends of the cooling rotor housing for supporting the rotation of the cooling rotor. Two annular flow channels communicating with the inlet liquid flow channel and the outlet liquid flow channel inside the cooling rotor 21 respectively are arranged in the inner cavity of the cooling rotor housing 22 for conveying cooling liquid during the rotation of the brake disc and the cooling rotor. Two annular sealing structures are respectively adopted on both sides of the annular oil channel in the inner cavity of the cooling rotor housing 22. A cooling liquid inlet and a cooling liquid outlet corresponding to the internal annular flow channel are arranged on the surface of the cooling rotor housing 22. The cooling rotor housing 22 is fixed to the hoist frame.

[0041] The described cooling hydraulic system 3 includes a liquid storage tank 31, a hydraulic pump 32, a switch valve 33, a coolant proportional flow valve 34, a relief valve 35, an oil suction filter 36, and a return liquid temperature sensor 37. The hydraulic pump 32 is connected to the coolant proportional flow valve 34 through a pipeline via the switch valve 33. The coolant proportional flow valve 34 is connected to the cooling liquid inlet on the cooling rotor housing 22 through a pipeline. One end of the relief valve 35 is bypassed to the hydraulic pump 32 and the other end is connected to the liquid storage tank 31. The oil suction filter 36 is connected to the liquid storage tank 31 and the hydraulic pump 32 through a pipeline. The cooling liquid outlet on the cooling rotor housing 22 is connected to the liquid storage tank 31 through a pipeline. The return liquid temperature sensor 37 is installed at the cooling liquid outlet on the cooling rotor housing 22.

[0042] The coolant circulation path inside the mine hoist emergency braking friction pair temperature rise suppression system of this embodiment is: liquid storage tank 31 - oil suction filter 36 - hydraulic pump 32 - switch valve 33 - coolant proportional flow valve 34 - cooling liquid inlet of cooling rotor housing 22 - annular flow oil corresponding to the cooling liquid inlet of cooling rotor housing 22 - inlet liquid flow channel of cooling rotor 21 - inlet hole of connecting frame 13 - inlet hole of cooling disc 12 - closed annular flow channel inside the brake disc 11 - outlet hole of cooling disc 12 - outlet hole of connecting frame 13 - outlet liquid flow channel of cooling rotor 21 - annular flow channel corresponding to the cooling liquid outlet of cooling rotor housing 22 - cooling liquid outlet of cooling rotor housing 22 - liquid storage tank 31.

[0043] As Figure 4 shown, the present invention also proposes a method for controlling the temperature rise of the mine hoist emergency braking friction pair, including the following steps:

[0044] Step S1: Collect the current temperature T of the brake disc 11 through the return liquid temperature sensor 37, and at the same time collect the current braking force F and the current running speed v of the hoist.

[0045] Step S2: When a braking signal is received, different calculation formulas are selected to calculate the theoretical output flow rate Q according to the different current temperatures T of the brake disc 11 collected. out Specifically as follows:

[0046] If T < T0, then Q out = 0.

[0047] If T0 ≤ T < T1, then

[0048] If T ≥ T1, then

[0049] Where: T0 is the trigger temperature threshold, T1 is the cooling mode switching threshold, T max is the maximum working temperature of the brake disc 11, Q max is the maximum output flow rate of the coolant proportion flow valve 34, Q base is the basic output flow rate, k T is the temperature error gain coefficient, k Fv is the braking power gain coefficient, F max is the maximum braking force, v max is the maximum hoisting speed of the hoist.

[0050] Step S3: Calculate the final output flow rate Q of the coolant proportion flow valve 34 final Specific formula is as follows:

[0051]

[0052] Step S4: Convert the obtained Q final into a voltage control signal and output it to the coolant proportion flow valve 34 to control the opening of the valve core of the coolant proportion flow valve 34 and thus change the coolant flow rate, and repeat the above steps S1 to S4.

[0053] The value range of the basic output flow rate Q base in this embodiment is Q base = (0.1 - 0.3)Q max The value range of the temperature error gain coefficient k T is k T = 0.1 - 0.5, and the value range of the braking power gain coefficient k Fv is k Fv = 0.4 - 0.6.

[0054] The value range of the trigger temperature threshold T0 in this embodiment is T0 = 0.1 - 0.3T max , and the value range of the cooling mode switching threshold T1 is T1 = (2 - 3)T0, and the maximum working temperature T of the brake disc 11 maxThe value range of is T max = 250 to 300 °C.

[0055] The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited thereto. All changes that can be made within the scope of knowledge possessed by those skilled in the art without departing from the gist of the present invention are within the scope of protection of the claims of the present invention.

Claims

1. An emergency braking friction pair temperature rise suppression system for a mine hoist, characterized in that Comprising: A brake disc cooling assembly (1), a cooling rotor assembly (2), and a cooling hydraulic system (3); The brake disc cooling assembly (1) includes a brake disc (11), a cooling disc (12), and a connecting frame (13). The brake disc (11) has an internally hollow annular sheet-like structure. The cooling disc (12) is a complete ring formed by circumferentially splicing several brake cooling blocks. The cooling disc (12) is embedded in the inner cavity of the brake disc (11). A sealed annular flow channel is formed between the side surface of the cooling disc (12) and the inside of the brake disc (11) through an annular sealing ring. The connecting frame (13) is in the shape of a cylindrical boss with an internally hollow structure. The connecting frame (13) is sleeved in the annular hole of the brake disc (11). The connecting frame (13) and the cooling disc (12) are respectively provided with corresponding liquid inlet holes and liquid outlet holes in the radial direction. One end of the connecting frame (13) is fixed to the hoist drum; The cooling rotor assembly (2) includes a cooling rotor (21) and a cooling rotor housing (22). The cooling rotor (21) is a solid cylinder. An inlet liquid flow channel and an outlet liquid flow channel are provided inside the cooling rotor (21). The inlet liquid flow channel and the outlet liquid flow channel inside the cooling rotor (21) are respectively connected to the liquid inlet hole and the liquid outlet hole of the connecting frame (13) through pipelines. One end of the cooling rotor (21) is fixed in the annular hole at the other end of the connecting frame (13) opposite to the hoist drum. The other end of the cooling rotor (21) is sleeved in the inner cavity of the cooling rotor housing (22). Two annular flow channels communicating with the inlet liquid flow channel and the outlet liquid flow channel inside the cooling rotor (21) respectively are provided in the inner cavity of the cooling rotor housing (22). A coolant inlet and a coolant outlet corresponding to the internal annular flow channel are provided on the surface of the cooling rotor housing (22). The cooling rotor housing (22) is fixed to the hoist frame; The cooling hydraulic system (3) includes a liquid storage tank (31), a hydraulic pump (32), a switch valve (33), a coolant proportional flow valve (34), a relief valve (35), an oil suction filter (36), and a return liquid temperature sensor (37). The hydraulic pump (32) is connected to the coolant proportional flow valve (34) through a pipeline via the switch valve (33). The coolant proportional flow valve (34) is connected to the coolant inlet on the cooling rotor housing (22) through a pipeline. One end of the relief valve (35) is connected in parallel to the hydraulic pump (32), and the other end is connected to the liquid storage tank (31). The oil suction filter (36) is connected to the liquid storage tank (31) and the hydraulic pump (32) through a pipeline. The coolant outlet on the cooling rotor housing (22) is connected to the liquid storage tank (31) through a pipeline. The return liquid temperature sensor (37) is installed at the coolant outlet on the cooling rotor housing (22).

2. The temperature rise suppression system for the emergency braking friction pair of a mine hoist according to claim 1, wherein The connection between the connecting frame (13) and the brake disc (11) adopts a circumferential bolt connection method.

3. The temperature rise suppression system of the emergency braking friction pair of a mine hoist according to claim 1, characterized in that The connection between the connecting frame (13) and the hoist drum adopts a welding method.

4. A temperature rise suppression system for the emergency braking friction pair of a mine hoist according to claim 1, characterized in that The number of brake cooling blocks used for the cooling disc (12) is 4 to 6.

5. The temperature rise suppression system of the emergency braking friction pair of a mine hoist according to claim 1, characterized in that, The liquid inlet hole and the liquid outlet hole on the connecting frame (13) are on the same straight line.

6. The temperature rise suppression system for the emergency braking friction pair of a mine hoist according to claim 1, characterized in that, The number of annular sealing rings between the side surface of the cooling disc (12) and the brake disc (11) is 2 to 4.

7. The temperature rise suppression system for the emergency braking friction pair of a mine hoist according to claim 1, characterized in that, On both sides of the inner cavity annular oil passage of the cooling rotor housing (22), 1 to 2 annular sealing structures are respectively adopted.

8. A temperature rise control method for the emergency braking friction pair of a mine hoist, based on the emergency braking friction pair temperature rise suppression system of the mine hoist described in any one of claims 1-7, characterized in that, It includes the following steps: Step S1: Collect the current temperature T of the brake disc (11) through the return liquid temperature sensor (37), and at the same time collect the current braking force F and the current hoist running speed v. Step S2: When a braking signal is received, different calculation formulas are selected to calculate the theoretical output flow rate Q according to the different current temperatures T of the brake disc (11) collected out , specifically as follows: If T < T0, then Q out = 0, If T0 ≤ T < T1, then If T ≥ T1, then where: T0 is the triggering temperature threshold, T1 is the cooling mode switching threshold, T max is the maximum operating temperature of the brake disc (11), Q max is the maximum output flow rate of the coolant proportion flow valve (34), Q base is the basic output flow rate, k T is the temperature error gain coefficient, k Fv is the braking power gain coefficient, F max is the maximum braking force, v max is the maximum hoisting speed of the hoist; Step S3: Calculate the final output flow rate Q of the coolant proportioning flow valve (34) final , and the specific formula is as follows: Step S4: Output the obtained Q final to a voltage control signal to the coolant proportional flow valve (34), control the opening of the spool of the coolant proportional flow valve (34), thereby changing the coolant flow rate, and repeat Step S1 to Step S4.

9. A method for controlling the temperature rise of the emergency braking friction pair of a mine hoist according to claim 8, characterized in that The basic output flow rate Q base has a value range of Q base =(0.1 to 0.3)Q max , and the temperature error gain coefficient k T has a value range of k T =0.1 to 0.5, and the braking power gain coefficient k Fv has a value range of k Fv =0.4 to 0.

6.

10. A method for controlling the temperature rise of an emergency braking friction pair of a mine hoist according to claim 8, characterized in that, The value range of the triggering temperature threshold T0 is T0 = 0.1 to 0.3T max , the value range of the cooling mode switching threshold T1 is T1 = (2 to 3)T0, and the maximum operating temperature T of the brake disc (11) max The value range of max is T = 250 to 300 °C.

Images