Cooling and flushing system of heavy-load quick-release wet-type brake winch and heavy-load circulating operation crawler crane

Abstract

The invention discloses a cooling and flushing system of a heavy-load quick-release wet-type brake winch and a heavy-load circulating operation crawler crane, which comprise a pump set, a cooler, a hydraulic oil tank and a hydraulic cooling and flushing regulator connected in series on a front driving loop of the cooler, the hydraulic cooling and flushing regulator is driven by a fan pump in the pump set, and cold oil is directly taken from the hydraulic oil tank to cool and flush the heavy-load quick-release wet brake winch. The reliability problem of the dynamic braking working condition of the heavy-load quick-release wet-type braking winch is solved, the optimal temperature control level can be achieved, a film formed by hydraulic oil in the gaps of the braking friction plates is kept in the optimal state, it is guaranteed that dry friction does not happen to the braking plates during braking, and the service life of the braking friction plates is prolonged. And heating ablation caused by dry friction between metal friction plate materials is greatly reduced only by shearing a braking torque formed by a hydraulic oil film between the braking friction plates, so that the metal friction plate can be durable and reliable for a long time.

Description

Technical Field

[0001] The present invention relates to the cooling and flushing technology of a wet brake hoist, and particularly to a cooling and flushing system for a heavy-duty quick-release wet brake hoist and a heavy-duty cyclic operation crawler crane. Background Art

[0002] The heavy-duty quick-release wet brake hoist is the main working mechanism of a heavy-duty cyclic operation crawler crane, which can realize the free-fall rapid descent of a heavy-load tool and the rapid descent function with controllable and adjustable braking force. It can realize dynamic braking during the descent process. Its free rapid descent control and the function control of controllable and adjustable braking force are realized through a wet brake. The wet brake mainly consists of parts such as a hydraulic piston, multiple groups of friction plates, and a brake spring.

[0003] In order to improve the reliability and service life of the brake of the heavy-duty quick-release wet brake hoist and make it durable, it is necessary to design a set of cooling and flushing system to forcibly cool and flush the friction plate assembly, which is the key core part of the quick-release wet dynamic brake, and timely and sufficiently cool and flush the frictional heat generated during its dynamic braking process, so as to ensure that the oil film viscosity between the friction plate groups can always work within the normal standard range, prevent the failure of the ultra-thin support oil film of the friction plate caused by temperature rise, prevent the failure of the dynamic friction braking characteristics protected by the oil film, prevent the dry friction ablation phenomenon without oil film between the brake pads, and at the same time can timely flush out the fine particles between the friction plates that fall off due to friction and flush them out of the brake cavity along with the flow of the hydraulic oil, keep the hydraulic oil inside the brake clean, eliminate the oil film damage and mechanical direct scratches caused by the pollution of fine particles falling off due to friction, and thus fundamentally solve the problem of the need for fault repair of the current heavy-duty quick-release wet brake hoist.

[0004] The cooling of the brake of the existing heavy-duty quick-release wet brake hoist mainly cools and flushes through the return oil of the main system. For example, Figure 1 and 2 shown (1. pump group, 2. check valve, 3. main system control valve, 4. balance valve, 5. hoist motor, 6. heavy-duty quick-release wet brake hoist, 8. brake flushing filter, 9. cooler, 10. hydraulic oil tank), the hydraulic oil is respectively led out from behind the main control valve and behind the cooler, and through the back pressure of the check valve 2 of the return oil, the hydraulic oil is backflushed into the brake for cooling and flushing. However, tracking its effect from the current actual application performance is not ideal, including: when the quick-release function of the hoist is started until the wet brake is started, often the main system of the hoist does not work, there is no flow or very little flow in the system circuit, and during the time when the brake pads of the brake generate frictional heat, no flow can enter the wet brake of the hoist through the return oil of the main system. Only during the non-quick-release operation state within the operation cycle can cooling and flushing be carried out, and timeliness cannot be guaranteed. For example,Figure 3 As shown; at the same time, the oil temperature of the oil return circuit is often relatively high after the main system works. Under the long-term cyclic high-load operation, the oil temperature before the cooler in the principle Figure 1 often reaches as high as about 80°C to 90°C, and it cannot play a cooling role; in the principle Figure 2 Although the oil temperature after the cooler can be controlled at about 70°C to 80°C, the problem of increased back pressure of the main system caused by adding a check valve after the cooler increases the risk of weld opening and oil leakage due to the increase in cooler pressure. At the same time, due to the instability of the oil return flow rate of the main system, the pressure fluctuation caused by the change in flow rate is large, and both the cooling flushing flow rate and pressure are unstable. Summary of the Invention

[0005] Object of the Invention: The object of the present invention is to provide a cooling and flushing system for a heavy-duty quick-release wet brake hoist and a heavy-duty cyclic operation crawler crane, which can achieve full-time, sufficient-flow, and controllable cooling and flushing of the heavy-duty quick-release wet brake hoist during the working process.

[0006] Technical Solution: To achieve the above object, a cooling and flushing system for a heavy-duty quick-release wet brake hoist according to the present invention includes a pump group, a cooler, and a hydraulic oil tank. The cooler is driven by the pump group to draw oil from the hydraulic oil tank, and further includes a hydraulic cooling and flushing regulator connected in series on the drive circuit before the cooler. The hydraulic cooling and flushing regulator is driven by the fan pump in the pump group and directly draws cold oil from the hydraulic oil tank to cool and flush the heavy-duty quick-release wet brake hoist.

[0007] Wherein, the hydraulic cooling and flushing regulator includes a drive motor and a cooling and flushing pump, and the cooling and flushing pump is driven by the drive motor.

[0008] Wherein, the flow rate of the cooling and flushing pump is adjustable.

[0009] Wherein, the drive motor is connected in series on the circuit where the fan pump in the pump group and the fan motor in the cooler are located.

[0010] Wherein, a first safety valve is provided in front of the drive motor.

[0011] Wherein, a second safety valve is provided at the outlet of the cooling and flushing pump.

[0012] Wherein, the displacement of the cooling and flushing pump is greater than the displacement of the fan pump in the pump group.

[0013] Wherein, the working pressure of the cooling and flushing pump is less than the working pressure of the fan pump in the pump group.

[0014] Wherein, a pressure and temperature sensor is provided in the oil sump of the heavy-duty quick-release wet brake hoist.

[0015] A heavy-duty cyclic operation crawler crane according to the present invention includes the cooling and flushing system of the above-mentioned heavy-duty quick-release wet-brake hoist.

[0016] Beneficial effects: The present invention has the following advantages: 1. The flow rate output by the hydraulic cooling and flushing regulator of the present invention is large and sustainable, and can cover the entire working cycle time of the system. It has the advantages of adjustable flushing flow rate and stable flushing circuit pressure; 2. The hydraulic cooling and flushing regulator directly sucks cold oil from the hydraulic oil tank, which can cool and flush the brake of the heavy-duty quick-release wet-brake hoist with the cold oil at the lowest temperature, enabling the brake of the heavy-duty quick-release wet-brake hoist to reach the most ideal temperature control level; 3. The hydraulic cooling and flushing regulator is directly connected in series on the cooling circuit of the original technical system, with flexible and convenient layout and strong versatility. Description of the drawings

[0017] Figure 1 It is a schematic diagram of the flushing system before the cooler;

[0018] Figure 2 It is a schematic diagram of the flushing system after the cooler;

[0019] Figure 3 It is a schematic diagram of the working cycle relationship of the hoist lifting - quick-release braking;

[0020] Figure 4 It is a schematic diagram of the cooling and flushing system of the heavy-duty quick-release wet-brake hoist according to the present invention;

[0021] Figure 5 It is a schematic diagram of the hydraulic cooling and flushing regulator according to the present invention. Detailed implementation manners

[0022] The technical solutions of the present invention will be described in detail below in conjunction with the embodiments and the drawings.

[0023] As Figure 4 shown, the present invention is based on Figure 1 (or Figure 2 ) shown in the flushing circuit before (or after) the cooler for improvement, and a hydraulic cooling and flushing regulator 2 is provided in this circuit to form the cooling and flushing system of the heavy-duty quick-release wet-brake hoist described in the present invention.

[0024] The hydraulic cooling and flushing regulator 2 is connected in series to the drive circuit in front of the fan motor in the cooler 9, and a pressure and temperature sensor 7 is arranged at the heavy-duty quick-release wet brake hoist 6 (the pressure and temperature sensor 7 is screwed into the oil sump of the heavy-duty quick-release wet brake hoist 6 for directly measuring the pressure and temperature in the oil sump). The composed cooling and flushing system for the new heavy-duty quick-release wet brake hoist includes: a pump unit 1, a hydraulic cooling and flushing regulator 2, a main system control valve 3, a balance valve 4, a hoist motor 5, a heavy-duty quick-release wet brake hoist 6, a pressure and temperature sensor 7, a brake flushing filter 8, a cooler 9, and a hydraulic oil tank 10.

[0025] As Figure 5 shown, the hydraulic cooling and flushing regulator 2 includes a drive motor 21, a variable-displacement cooling and flushing pump 22 with adjustable displacement, a first safety valve 23 arranged in front of the drive motor 21 for pressure safety protection of the drive motor, and a second safety valve 24 arranged at the outlet of the cooling and flushing pump 22 for pressure safety protection of the cooling and flushing pump 22 and the heavy-duty quick-release wet brake hoist 6 (excessive flushing oil pressure will also cause excessive pressure in the oil sump of the heavy-duty quick-release wet brake hoist 6, damaging the seal of the container). The cooling and flushing pump 22 can both cool the friction plates and the oil film and flush away pollutants (particulates, various particulates that damage friction braking products or colloidal particulates of hydraulic oil generated by cutting the hydraulic oil film gap).

[0026] Among them, the drive motor 21 is specifically connected in series to the oil circuit between the pump unit 1 (P3 fan pump) and the cooler 9 (fan motor). Under this structural design, the drive motor 21 is not directly driven by the engine, so there is no need to increase the length of the series pump to solve the layout space problem, nor is it necessary to add a power take-off device, saving costs and space. It is also not driven by an electric motor or an air pump, only using the oil source of the cooling fan pump in the original cooling system (the inlet of the cooling and flushing pump 22 is connected to the hydraulic oil tank 10 and directly sucks oil from the hydraulic oil tank 10, and the outlet of the variable-displacement cooling and flushing pump 22 is connected to the heavy-duty quick-release wet brake hoist 6).

[0027] The system matching calculation shows that the pressure difference of this motor is only 0.5 - 2 MPa. Calculated according to the normal working pressure range of the original cooling system, which is 7 - 16 MPa, the working pressure of the P3 fan pump of the pump unit 1 is 7.5 - 18 MPa, fully meeting the technical conditions for safe, durable, and reliable operation (10 bar = 1 MPa). The rated working pressure of a normal gear pump is higher than 200 bar. Therefore, when the hydraulic cooling and flushing regulator 7 operates, the pressure of the first safety valve 23 is set to 200 bar.

[0028] This hydraulic cooling and flushing regulator uses a small-displacement motor (drive motor 21) to drive a large-displacement pump (cooling and flushing pump 22). Through the difference in displacement between the motor and the pump (the drive motor has a small displacement, the cooling and flushing pump has a large displacement, the motor and the pump are connected by a common shaft and have the same rotational speed, the motor outputs a small flow rate, and the pump outputs a large displacement), flow amplification is achieved. Through the Q1 small-flow system, the system of the original 16-displacement P3 fan pump driving the cooler fan motor realizes the production of the Q2 large-flow system and is applied to the cooling and flushing of the brake.

[0029] The displacement of the above-mentioned cooling and flushing pump 22 is greater than the displacement of the fan pump of pump group 1, and the working pressure of the cooling and flushing pump 22 is less than the working pressure of the fan pump of pump group 1.

[0030] When the hydraulic cooling and flushing regulator 2 is working, the adjustable-displacement cooling and flushing pump 22 can perform dynamic displacement adjustment according to the changes in engine speed, the working load of the winch, and the temperature and pressure of the brake temperature and pressure sensor 7, adjust the cooling and flushing flow rate, so that the brake obtains the best flushing and cooling state. At the same time, as long as the engine is started, the flushing flow rate can be generated within the working cycle time. Especially during the dynamic braking time of the quick release operation, the cooling and flushing flow rate is guaranteed, and even the cooling and flushing flow rate is increased, which has obvious advantages over the original technical solution.

[0031] The adjustable-displacement cooling and flushing pump 22 directly sucks oil from the hydraulic oil tank. The hydraulic oil temperature of the hydraulic oil tank is the lowest temperature of the system, and the normal working oil temperature is about 40 - 60 °C. It can use the cold oil at the lowest temperature to cool and flush the brake, which is better than Figure 1 、 2 the system principle shown.

[0032] The hydraulic cooling and flushing regulator 2 is arranged flexibly and conveniently. Since its power input does not directly take power from the engine mechanical rotation port, nor from the pump group mechanical interface, nor through the motor and air pump for power taking. It is only connected in series in the cooling fan drive circuit of the original system through hydraulic pipelines, which is convenient for installation and layout.

[0033] The hydraulic cooling and flushing regulator 2 has a large and adjustable displacement, which can meet different brakes with various braking torques in the current cooling and flushing specifications of 20 L / min - 80 L / min. It has strong versatility and a wide coverage, and can solve the problems of almost all tonnage models in the current industry. At the same time, the brake temperature and pressure sensor 7 can monitor the pressure and temperature status of the wet brake, make the status of the wet brake obvious, and apply it in the cooling and flushing control strategy, solving the problems of uncontrollable flushing flow rate, pressure and temperature in the original technical system, including the problem of brake seal damage caused by excessive pressure fluctuation due to stable flow rate in the original technical system.

[0034] The above-mentioned cooling and flushing system for the heavy-duty fast-release wet brake hoist solves the reliability problem of the dynamic braking condition of the wet brake, enabling it to reach the most ideal temperature control level. The thin film formed by the hydraulic oil between the brake friction plate gaps remains in the most ideal state, ensuring that there is no dry friction between the brake pads during braking. During the sliding braking process of the brake pads, the braking torque is formed only by shearing the hydraulic oil film between the brake friction plates, thus greatly reducing the heat ablation caused by dry friction between the metal friction plate materials, enabling it to maintain long-term durability and reliability, and enabling the heavy-duty fast-release wet brake hoist with high dynamic braking performance to be more widely promoted and applied in domestic heavy-duty cyclic operation crawler cranes, enhancing the international competitiveness of high-end and high-value heavy equipment in this field in our country.

Claims

1. A cooling and flushing system for a heavy-load quick-release wet brake winch, comprising a pump group (1), a cooler (9), and a hydraulic oil tank (10), wherein the cooler (9) is driven by the pump group (1) taking oil from the hydraulic oil tank (10), and is characterized in that: It also includes a hydraulic cooling and flushing regulator (2) connected in series to the front driving circuit of the cooler (9). The hydraulic cooling and flushing regulator (2) is driven by the fan pump in the pump group (1) and directly takes cold oil from the hydraulic oil tank (10) to cool and flush the heavy-load quick-release wet brake winch (6).

2. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 1 is characterized in that: The hydraulic cooling and flushing regulator (2) comprises a driving motor (21) and a cooling and flushing pump (22), wherein the cooling and flushing pump (22) is driven by the driving motor (21).

3. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 2 is characterized in that: The flow rate and displacement of the cooling and flushing pump (22) are adjustable.

4. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 2 is characterized in that: The drive motor (21) is connected in series to the fan pump of the pump group (1) and the circuit where the fan motor in the cooler (9) is located.

5. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 2, characterized in that: A first safety valve (23) is arranged in front of the drive motor (21).

6. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 2, characterized in that: A second safety valve (24) is provided at the outlet of the cooling and flushing pump (22).

7. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 2, characterized in that: The displacement of the cooling and flushing pump (22) is greater than the displacement of the fan pump of the pump group (1).

8. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 2, characterized in that: The working pressure of the cooling and flushing pump (22) is lower than the working pressure of the fan pump of the pump group (1).

9. The cooling and flushing system for the heavy-load quick-release wet brake winch according to claim 1, characterized in that: A pressure and temperature sensor (7) is provided in the oil pool of the heavy-load quick-release wet brake winch (6).

10. A crawler crane for heavy-duty cyclic operation, characterized in that: A cooling and flushing system for a heavy-load quick-release wet brake winch comprising the system described in any one of claims 1 to 9.

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