Hydraulic suspension top supporting mechanism system of girder erection crane

Abstract

The invention belongs to the technical field of hydraulic suspension jacking mechanisms, and particularly relates to a hydraulic suspension jacking mechanism system of a girder erection crane. Comprising a motor, a series plunger variable pump, a supporting mechanism, a clamping mechanism and a walking mechanism, the motor is connected with the series plunger variable pump and used for driving the series plunger variable pump to operate, the series plunger variable pump sucks oil from a hydraulic oil tank, a front pump of the series plunger variable pump is used for providing a pressure oil source for the supporting mechanism and the walking mechanism, and a rear pump of the series plunger variable pump is used for providing a pressure oil source for the clamping mechanism. A rear pump of the series plunger variable pump is used for providing a pressure oil source for the clamping mechanism, pressure oil ports of a front pump and the rear pump of the series plunger variable pump are respectively provided with an electromagnetic overflow valve and a direct-acting overflow valve, an outlet of the front pump of the series plunger variable pump is provided with a pressure gauge, and the hydraulic oil tank is provided with a liquid level and liquid temperature meter and an air filter; according to the invention, the four supporting oil cylinders can actively and uniformly distribute the vertical force applied to the flexible bridge by the single suspension supporting mechanism of the crane, so that the stress requirement of the flexible bridge is met.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic suspension support mechanisms, and in particular relates to a hydraulic suspension support mechanism system of a beam erecting crane. Background Art

[0002] A beam erecting crane is a beam lifting equipment specially used in bridge construction. A beam erecting crane usually has a large lifting capacity to meet the lifting needs of bridge beams. Its stable structure ensures that it can maintain balance and stability during the lifting process. The application range of beam erecting machines is relatively narrow, mainly concentrated in the field of bridge construction. The working principle of a beam erecting crane is mainly based on its special structural design and lifting capacity. By operating the control system, precise control of the crane can be achieved, including lifting, lowering, forward, backward and other actions. During the lifting process, the crane uses its powerful lifting capacity and stable structure to lift the bridge beam from the ground or the transport vehicle and accurately place it in the predetermined position.

[0003] In the process of erecting a flexible bridge by using a beam erecting crane, since the rigidity of the flexible bridge is relatively weak, the beam erecting crane used for erecting the flexible bridge usually needs to specially design the support system so that the load-bearing capacity transmitted to the bridge by the support system can be reasonably distributed regardless of whether the crane is in the lifting condition or the walking condition. The beam erecting crane in the prior art is supported by multiple supporting oil cylinders at the bottom, and it cannot ensure that the multiple supporting oil cylinders actively and evenly distribute the vertical force applied to the flexible bridge by the single suspended supporting mechanism of the crane, resulting in the beam erecting crane in the prior art being unable to meet the force requirements of the flexible bridge. Therefore, it is very critical to design a reliable hydraulic oil pump system and electronic control system of the hydraulic suspended supporting mechanism. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a hydraulic suspension support mechanism system for a beam erecting crane.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A hydraulically suspended supporting mechanism system of a beam erecting crane of the present invention comprises a motor, a tandem piston variable pump, a supporting mechanism, a clamping mechanism and a traveling mechanism, wherein the motor is connected to the tandem piston variable pump, the motor is used to drive the tandem piston variable pump to operate, the tandem piston variable pump draws oil from a hydraulic oil tank, the front pump of the tandem piston variable pump is used to provide a pressure oil source to the supporting mechanism and the traveling mechanism, and the rear pump of the tandem piston variable pump is used to provide a pressure oil source to the clamping mechanism.

[0007] Furthermore, the supporting mechanism includes a supporting cylinder, a longitudinal shift cylinder and an oil return filter. The longitudinal shift cylinder includes a first longitudinal shift cylinder and a second longitudinal shift cylinder, and also includes a first electric proportional reversing valve, a second electric proportional reversing valve and a third electric proportional reversing valve. The outlet pressure oil of the front pump of the tandem plunger variable pump is connected to the oil inlet ports of the three electric proportional reversing valves. The two working oil ports of the first electric proportional reversing valve are respectively connected to the rodless chamber and the rod chamber of the supporting cylinder; the two working ports of the second electric proportional reversing valve and the third electric proportional reversing valve are respectively connected to the rodless chamber and the rod chamber of the first longitudinal shift cylinder and the second longitudinal shift cylinder; the return oil ports of the three electric proportional reversing valves all flow back to the hydraulic oil tank through the oil return filter.

[0008] Furthermore, the clamping mechanism includes a first clamping cylinder and a second clamping cylinder, the outlet pressure oil of the rear pump of the tandem plunger variable pump is connected to the oil inlet of the electromagnetic reversing valve, the two working oil ports of the electromagnetic reversing valve are respectively connected to the two chambers of the first clamping cylinder and the second clamping cylinder, the corresponding working oil ports of the first clamping cylinder and the second clamping cylinder are interconnected, and a two-way hydraulic lock is arranged on the two main pipelines of the first clamping cylinder and the second clamping cylinder.

[0009] Furthermore, the front pump and rear pump pressure oil ports of the series piston variable pump are respectively provided with an electromagnetic relief valve and a direct-acting relief valve.

[0010] Furthermore, there are four supporting top oil cylinders, and the rodless cavity pipelines of the four supporting top oil cylinders are connected, and the connecting pipelines are connected to the unloading valve, the accumulator and the safety valve group.

[0011] Furthermore, pressure sensors are arranged on the connecting pipelines of the four supporting cylinders, displacement sensors with analog output are built into the supporting cylinders, displacement sensors with analog output are arranged on the first longitudinal movement cylinder and the second longitudinal movement cylinder, and pressure sensors are arranged on the oil circuits of the first clamping cylinder and the second clamping cylinder.

[0012] Furthermore, a pressure gauge is provided at the front pump outlet of the tandem piston variable displacement pump.

[0013] Furthermore, the hydraulic oil tank is provided with a liquid level and temperature gauge and an air filter.

[0014] The beneficial effects of the present invention are as follows: under the condition of lifting weight, the middle steel support of the hydraulic suspension support mechanism and the four support cylinders jointly support the crane, the front pump of the series piston variable pump supplies oil to the large chamber of the support cylinder through the electric proportional reversing valve, and at the same time stores energy in the accumulator, when the accumulator pressure reaches the set pressure of the safety valve group, the electronic control system automatically shuts down the motor, the series piston variable pump stops running, and the accumulator ensures that the support force applied to the crane by the support cylinder is constant during the entire lifting process; when the pressure data signal received by the electronic control system from the sensor is lower than the theoretical limit value, the motor starts automatically, and continues to replenish oil to the accumulator through the electric proportional reversing valve until the accumulator pressure reaches the set value; this design can not only ensure that the four support cylinders can actively and evenly distribute the vertical force applied to the flexible bridge by the single suspension support mechanism of the crane, meet the force requirements of the flexible bridge, but also avoid the problems of high heat and high energy consumption caused by the motor and oil pump working under high pressure and large flow conditions for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0016] Figure 1 It is a schematic diagram of the hydraulic system of the present invention;

[0017] Figure 2 It is a three-dimensional schematic diagram of the hydraulic suspension support travel mechanism of the present invention.

[0018] Explanation of the reference numerals in the accompanying drawings: 1. Motor; 2. Serial piston variable pump; 3. Check valve; 4. Electromagnetic overflow valve; 5. Return oil filter; 6. Electromagnetic reversing valve; 71. First electric proportional reversing valve; 72. Second electric proportional reversing valve; 73. Third electric proportional reversing valve; 81. First longitudinal shift cylinder; 82. Second longitudinal shift cylinder; 91. First clamping cylinder; 92. Second clamping cylinder; 10. Bidirectional hydraulic lock; 11. Support cylinder; 12. Unloading valve; 13. Accumulator; 14. Safety valve group; 15. Liquid level and temperature gauge; 16. Air filter; 17. Pressure sensor; 18. Pressure gauge; 19. Direct-acting overflow valve. DETAILED DESCRIPTION

[0019] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0020] like Figure 1-Figure 2As shown, the hydraulic suspension support mechanism system of the beam erecting crane of the present invention is composed of a hydraulic oil pump system and an electric control system. The hydraulic oil pump system is composed of a motor 1, a series plunger variable pump 2, a check valve 3, an electromagnetic overflow valve 4, an electric proportional reversing valve, an electromagnetic reversing valve 6, a support cylinder 11, a longitudinal cylinder, a clamping cylinder, an accumulator 13, a pressure sensor 17, a displacement sensor and a hydraulic oil tank.

[0021] The motor 1 drives the tandem piston variable pump 2 to operate, and the tandem piston variable pump 2 draws oil from the hydraulic oil tank. The front pump of the tandem piston variable pump 2 provides a pressure oil source to the supporting mechanism and the walking mechanism, and the rear pump provides a pressure oil source to the clamping mechanism. The supporting mechanism includes a supporting cylinder 11, a longitudinal cylinder and an oil return filter 5. The longitudinal cylinder includes a first longitudinal cylinder 81 and a second longitudinal cylinder 82, and also includes a first electric proportional reversing valve 71, a second electric proportional reversing valve 72 and a third electric proportional reversing valve 73. The outlet pressure oil of the front pump of the tandem piston variable pump 2 is connected to the oil inlet P of the three electric proportional reversing valves. The two working oil ports A and B of the first electric proportional reversing valve 71 are respectively connected to the rodless chamber and the rod chamber of the supporting top cylinder 11; the two working ports A and B of the second electric proportional reversing valve 72 and the third electric proportional reversing valve 73 are respectively connected to the rodless chamber and the rod chamber of the first longitudinal cylinder 81 and the second longitudinal cylinder 82; the return oil ports of the three electric proportional reversing valves all flow back to the hydraulic oil tank through the return oil filter 5. The hydraulic oil tank is provided with a liquid level and temperature gauge 15 and an air filter 16. The outlet pressure oil of the rear pump of the tandem piston variable pump 2 is connected to the oil inlet P of the electromagnetic reversing valve 6, and the two working oil ports of the electromagnetic reversing valve 6 are respectively connected to the two chambers of the first clamping cylinder 91 and the second clamping cylinder 92. The corresponding working oil ports of the first clamping oil cylinder 91 and the second clamping oil cylinder 92 are interconnected. A two-way hydraulic lock 10 is set on the two main pipelines of the first clamping oil cylinder 91 and the second clamping oil cylinder 92 to lock the oil cylinder when the machine is shut down or the pipe bursts. The front and rear pump pressure oil ports of the series plunger variable pump 2 are respectively provided with an electromagnetic relief valve 4 and a direct-acting relief valve 19. The electromagnetic relief valve 4 plays the role of no-load starting and safety pressure limiting, and the direct-acting relief valve 19 plays the role of setting the clamping force. Since the middle position of the electromagnetic reversing valve 6 is a Y-type function, it has a middle position unloading function.

[0022] The rodless chamber pipelines of the four supporting top oil cylinders 11 are connected, and the connecting pipelines are connected in parallel with the unloading valve 12, the accumulator 13 and the safety valve group 14. The unloading valve 12 is electromagnetic, and plays an active unloading role through electric control. The accumulator 13 plays the role of absorbing pressure flushing and maintaining pressure, and the safety valve group 14 plays the role of safety pressure limiting.

[0023] In addition, a pressure sensor 17 is arranged on the connecting pipeline of the four supporting cylinders 11, the supporting cylinder 11 has a built-in displacement sensor with 4-20mA analog output, the first longitudinal movement cylinder 81 and the second longitudinal movement cylinder 82 have their own displacement sensors with 4-20mA analog output, and a pressure sensor 17 is arranged on the oil circuit of the first clamping cylinder 91 and the second clamping cylinder 92.

[0024] During the control process, it also includes a control device, which is electrically connected to various electrical appliances in the hydraulic oil pump system. Under the lifting condition, the central steel support of the hydraulic suspension support mechanism and the four support cylinders 11 jointly support the crane. The front pump of the series piston variable pump 2 supplies oil to the large chamber of the support cylinder 11 through the electric proportional reversing valve, and at the same time stores energy in the accumulator 13. When the pressure of the accumulator 13 reaches the set pressure of the safety valve group 14, the electronic control system automatically turns off the motor 1, and the series piston variable pump 2 stops running. The accumulator 13 ensures that the support force applied to the crane by the support cylinder 11 is constant during the entire lifting process. When the pressure data signal received by the electronic control system from the sensor is lower than the theoretical limit value, the motor 1 automatically starts and continues to replenish oil to the accumulator 13 through the electric proportional reversing valve until the pressure of the accumulator 13 reaches the set value. This design can not only ensure that the four supporting cylinders 11 can actively and evenly distribute the vertical force applied to the flexible bridge by the single suspended supporting mechanism of the crane to meet the force requirements of the flexible bridge, but also avoid the problems of high heat and high energy consumption caused by the motor 1 and the oil pump working under high pressure and high flow conditions for a long time.

[0025] During the operation, before the crane is ready to move longitudinally, the front pump of the series piston variable pump 2 supplies oil to the large chamber of the support top cylinder 11 through the electric proportional reversing valve, and the electronic control system lifts the crane to the designed height according to the displacement data information fed back by the built-in displacement sensor of the support top cylinder 11. During the longitudinal movement of the crane, when the bearing surface of the flexible bridge is uneven or there is a sudden change in the plane, the four support top cylinders 11 are connected to each other without rod cavities, and automatically adapt to the impact of uneven road surface. When the pipeline between the proportional valve and the working oil port of the cylinder bursts, the integrated balance valve on the support top cylinder 11 will quickly self-lock the cylinder; when the connecting pipeline between the four support top cylinders 11 bursts, the integrated explosion-proof valve on the support top cylinder 11 can also lock the cylinder. This design is highly safe.

[0026] During the operation, under the condition of longitudinal movement of the crane, the front pump of the series piston variable pump 2 supplies oil to the first longitudinal movement cylinder 81 and the second longitudinal movement cylinder 82 through the second electric proportional reversing valve 72 and the third electric proportional reversing valve 73 respectively. The electronic control system identifies the displacement difference between the first longitudinal movement cylinder 81 and the second longitudinal movement cylinder 82 according to the displacement data information fed back by the displacement sensor integrated on the longitudinal movement cylinder. The high-precision PLC controller controls the displacement difference between the first longitudinal movement cylinder 81 and the second longitudinal movement cylinder 82 through the amplifier board of the proportional valve. The program adopts the PID algorithm to adjust the input current value of the electromagnet of the second electric proportional reversing valve 72 and the third electric proportional reversing valve 73 to achieve millimeter-level synchronous control.

[0027] The function of the first clamping oil cylinder 91 and the second clamping oil cylinder 92 is to push the clamping mechanism so that the reaction seat of the longitudinal movement oil cylinder can overcome the horizontal force of the longitudinal movement of the crane. Since the beam erecting crane used for the erection of flexible bridges is supported by a roller car, the horizontal force generated by the longitudinal movement is often relatively small, and the longitudinal movement speed requirements are relatively low, so the clamping force and speed requirements of the first clamping oil cylinder 91 and the second clamping oil cylinder 92 are very low. The action of the clamping mechanism is powered by the tail pump of the series piston variable pump 2, which has a small flow rate. The first clamping oil cylinder 91 and the second clamping oil cylinder 92 are supplied with oil through the switch type electromagnetic reversing valve 6. During the clamping process, the accumulator 13 is no longer set separately. The clamping force is set by the direct-acting relief valve 19, and the electronic control system can receive the clamping pressure through the pressure sensor 17 set in the rodless cavity of the first clamping oil cylinder 91 and the second clamping oil cylinder 92.

[0028] Furthermore, a pressure gauge 18 is provided at the front pump outlet of the tandem piston variable pump 2.

[0029] The bottom of the beam erecting crane has a set of identical trolleys to support the weight of the whole machine and serve as the driving mechanism for the longitudinal movement of the whole machine. Each set of trolleys is equipped with a hydraulic pump station. Along the direction of the bridge, the two trolleys at the front are independent of each other; the two trolleys at the rear are independent of each other under the beam hoisting condition, and all the 11 large chambers of the supporting cylinders of the two trolleys are connected to each other under the longitudinal movement condition.

[0030] There are two main operating conditions for the trolley, including longitudinal movement and beam lifting.

[0031] When in longitudinal shifting condition: before longitudinal shifting, the four trolleys are in independent mode, and the bolts between the trolleys and the steel beams are first released manually. Then the four trolley groups are electrically operated to lift 50mm respectively. Operate the shut-off valve interconnection button to connect the 11 large chambers of all the supporting cylinders of the two rear trolleys. Then, operate the longitudinal shifting of the whole machine. At this time, the program controls the 8 longitudinal shifting cylinders of the whole machine to synchronously drive the crane forward or backward. The longitudinal shifting mechanism of the whole machine consists of 8 longitudinal shifting cylinders and 8 clamping cylinders. The longitudinal shifting cylinder is the driving mechanism, and the clamping cylinder only provides the clamping force, which is the reaction seat of the longitudinal shifting cylinder.

[0032] When in the beam lifting condition, before the beam is lifted, all the supporting cylinders 11 of the two rear trolleys are in a connected state. First, the four trolleys are operated by electric control to retract their legs at the same time, so that the middle steel support of each trolley is in close contact with the top surface of the "Π"-shaped beam, and then all the steel supports on the four trolleys are manually locked with bolts to the "Π"-shaped beam. Reset the stop valve interconnection button to make the two rear trolleys independent of each other. Operate the four trolleys to extend the piston rods of the jacking cylinders. When the large chamber pressure signal of each set of trolley jacking cylinders indicates 12.5MPa, the lifting action stops. At this time, the trolley state has met the conditions for beam lifting operations. During the beam lifting process, when the pressure sensor 17 of the jacking cylinder of any of the four trolleys drops to 10.5MPa, the electronic control system automatically operates the trolley jacking cylinder piston rod to extend until the pressure signal indicates that it stops at 12.5MPa.

[0033] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A hydraulic suspension support mechanism system for a beam erecting crane, characterized in that: It includes a motor, a tandem piston variable pump, a support mechanism, a clamping mechanism and a traveling mechanism, wherein the motor is connected to the tandem piston variable pump, and the motor is used to drive the tandem piston variable pump to operate. The tandem piston variable pump draws oil from a hydraulic oil tank, the front pump of the tandem piston variable pump is used to provide a pressure oil source to the support mechanism and the traveling mechanism, and the rear pump of the tandem piston variable pump is used to provide a pressure oil source to the clamping mechanism.

2. The hydraulic suspension support mechanism system of a beam erecting crane according to claim 1, characterized in that: The supporting mechanism includes a supporting cylinder, a longitudinal movement cylinder and an oil return filter. The longitudinal movement cylinder includes a first longitudinal movement cylinder and a second longitudinal movement cylinder, and also includes a first electric proportional reversing valve, a second electric proportional reversing valve and a third electric proportional reversing valve. The outlet pressure oil of the front pump of the tandem plunger variable pump is connected to the oil inlet ports of the three electric proportional reversing valves. The two working oil ports of the first electric proportional reversing valve are respectively connected to the rodless chamber and the rod chamber of the supporting cylinder; the two working ports of the second electric proportional reversing valve and the third electric proportional reversing valve are respectively connected to the rodless chamber and the rod chamber of the first longitudinal movement cylinder and the second longitudinal movement cylinder; the oil return ports of the three electric proportional reversing valves all flow back to the hydraulic oil tank through the oil return filter.

3. The hydraulic suspension support mechanism system of a beam erecting crane according to claim 2, characterized in that: The clamping mechanism includes a first clamping cylinder and a second clamping cylinder. The outlet pressure oil of the rear pump of the tandem plunger variable pump is connected to the oil inlet of the electromagnetic reversing valve. The two working oil ports of the electromagnetic reversing valve are respectively connected to the two chambers of the first clamping cylinder and the second clamping cylinder. The corresponding working oil ports of the first clamping cylinder and the second clamping cylinder are interconnected. A two-way hydraulic lock is arranged on the two main pipelines of the first clamping cylinder and the second clamping cylinder.

4. The hydraulic suspension support mechanism system of a beam erecting crane according to claim 1, characterized in that: The front pump and rear pump pressure oil ports of the series piston variable pump are respectively provided with an electromagnetic relief valve and a direct-acting relief valve.

5. The hydraulic suspension support mechanism system of a beam erecting crane according to claim 3, characterized in that: There are four supporting top oil cylinders, and the rodless cavity pipelines of the four supporting top oil cylinders are connected, and the connecting pipelines are connected with an unloading valve, an accumulator and a safety valve group.

6. The hydraulic suspension support mechanism system of a beam erecting crane according to claim 5, characterized in that: Pressure sensors are arranged on the connecting pipelines of the four supporting cylinders, displacement sensors with analog output are built in the supporting cylinders, displacement sensors with analog output are arranged on the first longitudinal movement cylinder and the second longitudinal movement cylinder, and pressure sensors are arranged on the oil circuits of the first clamping cylinder and the second clamping cylinder.

7. The hydraulic suspension support mechanism system of a beam erecting crane according to claim 1, characterized in that: A pressure gauge is provided at the front pump outlet of the tandem plunger variable pump.

8. The hydraulic suspension support mechanism system of a beam erecting crane according to claim 1, characterized in that: The hydraulic oil tank is provided with a liquid level and temperature gauge and an air filter.

Images