阅读说明：本技术 一种强夯机的自由下落夯锤减速控制方法及系统 (Deceleration control method and system for free falling rammer of dynamic compaction machine ) 是由 张俊强 于 2019-11-12 设计创作，主要内容包括：本发明公开了一种强夯机的自由下落夯锤减速控制方法及系统,在非脱钩模式夯锤自由下落过程中,在夯锤未着地之前,控制卷扬机进行一级制动；在夯锤着地时,控制卷扬机进行二级制动。本发明可以在非脱钩模式工作,减少对卷扬机冲击力,防止造成卷扬机损坏,减少卷扬机的起重钢丝绳出绳量,防止影响下一次夯击。(The invention discloses a speed reduction control method and system for a free falling rammer of a dynamic compactor, wherein in the free falling process of the rammer in a non-unhooking mode, a winch is controlled to perform primary braking before the rammer is not grounded; and when the rammer lands, controlling the winch to perform secondary braking. The invention can work in a non-unhooking mode, reduces the impact force on the winch, prevents the damage of the winch, reduces the rope outlet amount of a hoisting steel wire rope of the winch and prevents the influence on next tamping.)

1. A speed reduction control method for a free falling rammer of a dynamic compactor is characterized in that a winch is controlled to perform primary braking before the rammer is not grounded in the free falling process of the rammer in a non-unhooking mode; and when the rammer lands, controlling the winch to perform secondary braking.

2. The method for deceleration control of a free-falling ram of a dynamic compactor according to claim 1, wherein the braking force of the primary brake is smaller than the secondary braking force, the primary brake decelerates the hoist without stopping rotation, and the secondary brake stops rotation of the hoist.

3. The method for controlling the deceleration of the free falling rammer of the dynamic compactor according to claim 1, wherein the falling distance height of the rammer of the dynamic compactor and the deceleration braking height before the rammer is not grounded are set, the ramming frequency is set, and the current ramming frequency is obtained by obtaining a hammer starting execution feedback signal and calculating; setting different deceleration braking heights according to different drop heights; the smaller the drop height is, the smaller the deceleration braking height is; the larger the drop height, the larger the deceleration braking height.

4. A speed reduction control system of a free falling rammer of a dynamic compaction machine is characterized by comprising a controller, a primary brake pump (108), a secondary brake pump (102), a primary brake clamp (105) and a secondary brake clamp (103); the primary brake clamp (105) and the secondary brake clamp (103) are arranged on a brake disc of the winch; the primary brake pump (108) drives the primary brake clamp (105) to brake, the secondary brake pump (102) drives the secondary brake clamp (103) to brake, and the pressure of a primary brake air source supplied to the primary brake pump (108) is smaller than the pressure of a secondary brake air source supplied by the secondary brake pump (102);

in the free falling process of the rammer in the non-unhooking mode, before the rammer is not landed, the controller sends a primary braking instruction to enable a primary braking pump (108) to drive a primary braking clamp (105) to brake for primary braking; when the rammer lands, the controller sends out a secondary braking command, so that the secondary braking pump (102) drives a secondary braking clamp (103) to perform secondary braking.

5. The free-fall ram deceleration control system of a dynamic compactor according to claim 4, comprising a primary altitude braking electromagnetic gas valve (115), a secondary altitude braking electromagnetic gas valve (116), a first pneumatic valve (114), a second pneumatic valve (113), a primary vent valve (109), a secondary vent valve (101); the air inlet of the first-level brake pump (108) is communicated with the air outlet of the first pneumatic valve (114), the air outlet of the first-level height brake electromagnetic air valve (115) is communicated with the air inlet of the first-level exhaust valve (109), and the air outlet of the first-level exhaust valve (109) is communicated with the control port of the first pneumatic valve (114); the air inlet of the first pneumatic valve (114) is connected with a primary brake air source;

an air inlet of the secondary brake pump (102) is communicated with an air outlet of the second pneumatic valve (113), an air outlet of the secondary height brake electromagnetic air valve (116) is communicated with an air inlet of the secondary exhaust valve (101), and an air outlet of the secondary exhaust valve (101) is communicated with a control port of the second pneumatic valve (113); an air inlet of the second pneumatic valve (113) is connected with a secondary braking air source;

the air inlet of the first-level height braking electromagnetic air valve (115) and the air inlet of the second-level height braking electromagnetic air valve (116) are connected with a pilot control air source;

the controller sends a primary braking instruction to the primary height braking electromagnetic air valve (115), so that an air inlet and an air outlet of the primary height braking electromagnetic air valve (115) are communicated, and a primary brake pump (108) drives a primary brake clamp (105) to brake to perform primary braking; the controller sends a secondary braking instruction to the secondary height braking electromagnetic air valve (116), so that an air inlet and an air outlet of the secondary height braking electromagnetic air valve (116) are communicated, and the secondary braking pump (102) drives the secondary braking clamp (103) to perform secondary braking.

6. The free-fall ram deceleration control system of a dynamic compactor according to claim 4, comprising a primary altitude braking electromagnetic gas valve (115), a secondary altitude braking electromagnetic gas valve (116), a first pneumatic valve (114), a second pneumatic valve (113), a primary vent valve (109), a secondary vent valve (101); an air inlet of the primary brake pump (108) is communicated with an air outlet of the primary exhaust valve (109), and an air outlet of the first pneumatic valve (114) is communicated with an air inlet of the primary exhaust valve (109); the air outlet of the first-level height braking electromagnetic air valve (115) is communicated with the control port of the first pneumatic valve (114); the air inlet of the first pneumatic valve (114) is connected with a primary brake air source;

an air inlet of the secondary brake pump (102) is communicated with an air outlet of the second pneumatic valve (113), an air outlet of the secondary height brake electromagnetic air valve (116) is communicated with an air inlet of the secondary exhaust valve (101), and an air outlet of the secondary exhaust valve (101) is communicated with a control port of the second pneumatic valve (113); an air inlet of the second pneumatic valve (113) is connected with a secondary braking air source;

the air inlet of the first-level height braking electromagnetic air valve (115) and the air inlet of the second-level height braking electromagnetic air valve (116) are connected with a pilot control air source;

the controller sends a primary braking instruction to the primary height braking electromagnetic air valve (115), so that an air inlet and an air outlet of the primary height braking electromagnetic air valve (115) are communicated, and a primary brake pump (108) drives a primary brake clamp (105) to brake to perform primary braking; the controller sends a secondary braking instruction to the secondary height braking electromagnetic air valve (116), so that an air inlet and an air outlet of the secondary height braking electromagnetic air valve (116) are communicated, and the secondary braking pump (102) drives the secondary braking clamp (103) to perform secondary braking.

7. The system for deceleration control of a free-falling ram of a dynamic compactor according to any one of claims 4 to 6, wherein the braking force of the primary brake is smaller than the secondary braking force, the primary brake decelerates the hoist without stopping rotation, and the secondary brake stops rotation of the hoist.

8. The system for controlling the deceleration of a free-falling ram of a dynamic compactor according to any one of claims 4 to 6, wherein the falling distance height of the ram of the dynamic compactor and the deceleration braking height before non-landing are set in the controller, the number of times of ramming is set in the controller, and the current number of times of ramming is calculated by obtaining a ram-up execution feedback signal; setting different deceleration braking heights according to different drop heights; the smaller the drop height is, the smaller the deceleration braking height is; the larger the drop height, the larger the deceleration braking height.

9. The free-fall ram deceleration control system of a dynamic compactor according to any one of claims 4 to 6, comprising an oil tank, an oil pump (107), a first one-way valve (106), a second one-way valve (104);

an oil outlet of the first check valve (106) is connected with an oil inlet A of the primary braking clamp (105), and an oil inlet of the first check valve (106) is connected with an oil inlet path; an oil outlet B of the primary brake clamp (105) is connected with an oil outlet P of a primary brake pump (108), and an oil return port T of the primary brake pump (108) is connected with an oil return path;

an oil outlet of the second check valve (104) is connected with an oil inlet A of the secondary braking clamp (103), and an oil inlet of the second check valve (104) is connected with an oil inlet path; an oil outlet B of the secondary brake clamp (103) is connected with an oil outlet P of the secondary brake pump (102), and an oil return port T of the secondary brake pump (102) is connected with an oil return path;

hydraulic oil in the oil tank sequentially passes through the oil pump (107) to be divided into two hydraulic oil paths, and the first hydraulic oil path sequentially passes through the first one-way valve (106), an oil inlet A of the primary brake clamp (105), an oil outlet B of the primary brake clamp (105), an oil outlet P of the primary brake pump (108) and an oil return port T of the primary brake pump (108) to return to an oil tank to form heat dissipation circulation; and the second hydraulic oil path sequentially passes through a second one-way valve (104), an oil inlet A of the secondary brake clamp (103), an oil outlet B of the secondary brake clamp (103), an oil outlet P of the secondary brake pump (102) and an oil return port T of the secondary brake pump (102) to form heat dissipation circulation.

10. The deceleration control system of the free fall rammer of the dynamic compactor according to any one of claims 5 to 6, characterized by comprising a non-unhooking mode pneumatic control valve (100), wherein a pilot control air source is communicated with an air inlet of the non-unhooking mode pneumatic control valve (100), and an air outlet of the non-unhooking mode pneumatic control valve (100) is communicated with an air inlet of a primary height braking electromagnetic air valve (115) and an air inlet of a secondary height braking electromagnetic air valve (116).

Technical Field

The invention relates to the field of machinery, in particular to a foot-operated braking method and system for a winch.

Background

The dynamic compactor uses a winch to repeatedly and vertically lift a rammer, and uses high impact generated by the high fall of the rammer to tamp the foundation. The tamping energy of the dynamic compactor is the height of the falling distance x the weight of the rammer, for example: the weight of the rammer is 30T, the drop height is 15m, and the ramming energy is 30 multiplied by 15 to 450KN. The drop height refers to the free drop height of the ram. The working mode of the dynamic compactor comprises a unhooking mode and a non-unhooking mode, wherein the unhooking mode refers to the mode that a unhooking device is connected to a hoisting steel wire rope of the dynamic compactor, the unhooking device hooks a rammer to the height of a falling distance (namely a ramming state), the unhooking device releases the rammer (namely a ramming state), the rammer falls freely, and the unhooking device does not fall along with the rammer. The unhooking mode is that a hoisting steel wire rope of the dynamic compactor is directly connected with a rammer, after the rammer is lifted to a falling distance height (namely, in a rammer lifting state), a brake mechanism and a clutch mechanism of the winch are loosened, the rammer falls freely (namely, in a rammer releasing state), and the winch rotates reversely under the pulling force of the rammer. Because the unhooking mode is ramming the in-process at every turn, all need transfer jack-up wire rope and detacher and rammer couple the action, cause the work efficiency of unhooking mode very low, non-unhooking mode is ramming the in-process at every turn, need not transfer jack-up wire rope and couple the action, consequently, the work efficiency of non-unhooking mode is higher than the work efficiency of unhooking mode far away.

At present, current dynamic compactor can only work under unhook mode, can not work under non-unhook mode, because when non-unhook mode, the hoist engine reverses under the pulling force of ram, the ram falling speed of free fall is very fast, make hoist engine reverse speed very high, it is very big to the hoist engine impact force, cause the hoist engine to damage easily, in addition, after the ramming, the ram lands, the hoist engine is under inertial effect, the hoist engine chance continues to rotate, the jack-up wire rope play rope volume that causes the hoist engine can be many, next ramming of influence. Therefore, before the rammer lands, the speed is reduced, the descending speed of the rammer is controlled, the braking distance of secondary braking is reduced, and when the rammer lands, the winch needs to be fully braked, so that the rope outlet quantity of a hoisting steel wire rope of the winch is reduced. Because the existing dynamic compactor only comprises a brake mechanism, the functions cannot be realized. Therefore, a new braking system and a new winch need to be developed, and the dynamic compactor can work in a non-unhooking mode.

Disclosure of Invention

In view of the above, the invention provides a foot-operated braking method and system for a winch, which can work in a non-unhooking mode, reduce impact force on the winch, prevent the winch from being damaged, reduce the rope discharging amount of a hoisting steel wire rope of the winch, and prevent the next tamping from being influenced.

On one hand, the invention provides a speed reduction control method for a free falling rammer of a dynamic compactor, wherein in the free falling process of the rammer in a non-unhooking mode, a winch is controlled to perform primary braking before the rammer lands; and when the rammer lands, controlling the winch to perform secondary braking.

Furthermore, the braking force of the primary brake is smaller than that of the secondary brake, the primary brake enables the winch to decelerate without stopping rotation, and the secondary brake enables the winch to stop rotation.

Furthermore, setting the falling distance height of the rammer of the dynamic compaction machine and the deceleration braking height before the rammer is not landed, setting the ramming times, and obtaining a rammer starting execution feedback signal to calculate to obtain the current ramming times; setting different deceleration braking heights according to different drop heights; the smaller the drop height is, the smaller the deceleration braking height is; the larger the drop height, the larger the deceleration braking height.

In addition, the invention also provides a free falling rammer deceleration control system of the dynamic compactor, which comprises a controller, a primary brake pump, a secondary brake pump, a primary brake clamp and a secondary brake clamp; the primary brake clamp and the secondary brake clamp are arranged on a brake disc of the winch; the primary brake pump drives the primary brake clamp to brake, the secondary brake pump drives the secondary brake clamp to brake, and the pressure of a primary brake air source supplied to the primary brake pump is smaller than the pressure of a secondary brake air source supplied by the secondary brake pump;

in the process of free falling of the rammer in the non-unhooking mode, when the rammer is not landed, the controller sends a primary braking instruction to enable a primary braking pump to drive a primary braking clamp to brake for primary braking; when the rammer lands on the ground, the controller sends a secondary braking instruction to enable the secondary braking pump to drive the secondary braking clamp to perform secondary braking.

The first embodiment of the invention comprises a first-level height braking electromagnetic air valve, a second-level height braking electromagnetic air valve, a first pneumatic valve, a second pneumatic valve, a first-level exhaust valve and a second-level exhaust valve; the air inlet of the first-level brake pump is communicated with the air outlet of the first pneumatic valve, the air outlet of the first-level height brake electromagnetic air valve is communicated with the air inlet of the first-level exhaust valve, and the air outlet of the first-level exhaust valve is communicated with the control port of the first pneumatic valve; the air inlet of the first pneumatic valve is connected with a primary braking air source;

the air inlet of the second-stage brake pump is communicated with the air outlet of the second pneumatic valve, the air outlet of the second-stage height brake electromagnetic air valve is communicated with the air inlet of the second-stage exhaust valve, and the air outlet of the second-stage exhaust valve is communicated with the control port of the second pneumatic valve; an air inlet of the second pneumatic valve is connected with a secondary braking air source;

the air inlet of the first-level height braking electromagnetic air valve and the air inlet of the second-level height braking electromagnetic air valve are connected with a pilot control air source;

the controller sends a first-level braking instruction to the first-level height braking electromagnetic air valve, so that an air inlet and an air outlet of the first-level height braking electromagnetic air valve are communicated, and a first-level brake pump drives a first-level brake clamp to brake to perform first-level braking; the controller sends a second-level braking instruction to the second-level height braking electromagnetic air valve, so that an air inlet of the second-level height braking electromagnetic air valve is communicated with an air outlet, and a second-level brake pump drives a second-level brake clamp to perform second-level braking.

A second embodiment of the invention comprises a primary height braking electromagnetic air valve, a secondary height braking electromagnetic air valve, a first pneumatic valve, a second pneumatic valve, a primary exhaust valve and a secondary exhaust valve; the air inlet of the first-stage brake pump is communicated with the air outlet of the first-stage exhaust valve, and the air outlet of the first pneumatic valve is communicated with the air inlet of the first-stage exhaust valve; the air outlet of the first-level height braking electromagnetic air valve is communicated with the control port of the first pneumatic valve; the air inlet of the first pneumatic valve is connected with a primary braking air source;

the air inlet of the second-stage brake pump is communicated with the air outlet of the second pneumatic valve, the air outlet of the second-stage height brake electromagnetic air valve is communicated with the air inlet of the second-stage exhaust valve, and the air outlet of the second-stage exhaust valve is communicated with the control port of the second pneumatic valve; an air inlet of the second pneumatic valve is connected with a secondary braking air source;

the air inlet of the first-level height braking electromagnetic air valve and the air inlet of the second-level height braking electromagnetic air valve are connected with a pilot control air source;

the controller sends a first-level braking instruction to the first-level height braking electromagnetic air valve, so that an air inlet and an air outlet of the first-level height braking electromagnetic air valve are communicated, and a first-level brake pump drives a first-level brake clamp to brake to perform first-level braking; the controller sends a second-level braking instruction to the second-level height braking electromagnetic air valve, so that an air inlet of the second-level height braking electromagnetic air valve is communicated with an air outlet, and a second-level brake pump drives a second-level brake clamp to perform second-level braking.

Furthermore, the braking force of the primary brake is smaller than that of the secondary brake, the primary brake enables the winch to decelerate without stopping rotation, and the secondary brake enables the winch to stop rotation.

Furthermore, the falling distance height of the rammer of the dynamic compaction machine and the deceleration braking height before the rammer is not landed are set in the controller, the ramming times are set in the controller, and a rammer starting execution feedback signal is obtained to calculate the current ramming times; setting different deceleration braking heights according to different drop heights; the smaller the drop height is, the smaller the deceleration braking height is; the larger the drop height, the larger the deceleration braking height.

Further, the oil pump comprises an oil tank, an oil pump, a first one-way valve and a second one-way valve;

an oil outlet of the first one-way valve is connected with an oil inlet A of the primary braking clamp, and an oil inlet of the first one-way valve is connected with an oil inlet path; an oil outlet B of the primary brake clamp is connected with an oil outlet P of the primary brake pump, and an oil return port T of the primary brake pump is connected with an oil return path;

an oil outlet of the second one-way valve is connected with an oil inlet A of the secondary braking clamp, and an oil inlet of the second one-way valve is connected with an oil inlet path; an oil outlet B of the secondary brake clamp is connected with an oil outlet P of a secondary brake pump, and an oil return port T of the secondary brake pump is connected with an oil return path;

hydraulic oil in the oil tank sequentially passes through the oil pump to divide two hydraulic oil paths, and a first hydraulic oil path sequentially passes through the first one-way valve, the oil inlet A of the primary brake clamp, the oil outlet B of the primary brake clamp, the oil outlet P of the primary brake pump and the oil return port T of the primary brake pump to return to the oil tank to form heat dissipation circulation; and the second hydraulic oil way sequentially passes through the second one-way valve, the oil inlet A of the secondary brake clamp, the oil outlet B of the secondary brake clamp, the oil outlet P of the secondary brake pump and the oil return tank T of the oil return port T of the secondary brake pump to form heat dissipation circulation.

And the air outlet of the non-unhooking mode pneumatic control valve is communicated with the air inlet of the first-level height braking electromagnetic air valve and the air inlet of the second-level height braking electromagnetic air valve.

Compared with the prior art, the free falling rammer deceleration control method and the system of the dynamic compaction machine have the beneficial effects that:

1. the invention can work in a non-unhooking mode, reduces the impact force on the winch, prevents the damage of the winch, reduces the rope outlet amount of a hoisting steel wire rope of the winch and prevents the influence on next tamping.

2. Under the condition that the first-stage brake clamp and the second-stage brake clamp are not braked, the first hydraulic oil path and the second hydraulic oil path are both heat dissipation circulating oil paths, heat dissipation is carried out through an oil tank heat dissipation system, the brake heat dissipation effect is good, and the brake performance is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic structural diagram of a first embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a second embodiment of the present invention;

FIG. 3 is a schematic view of the first and second brake caliper mounting structures of FIGS. 1 and 2.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in FIGS. 1 and 2, the invention provides a deceleration control method and a system for a free falling rammer of a dynamic compactor, which comprises a primary brake pump 108, a secondary brake pump 102, a primary brake clamp 105 and a secondary brake clamp 103; the primary brake caliper 105 and the secondary brake caliper 103 are mounted on the brake disc of the hoist (as shown in fig. 3); the primary brake pump 108 drives the primary brake clamp 105 to brake, the secondary brake pump 102 drives the secondary brake clamp 103 to brake, and the pressure of a primary brake air source supplied to the primary brake pump 108 is smaller than that of a secondary brake air source supplied to the secondary brake pump 102.

The primary braking clamp 105 implements primary braking and the secondary braking clamp 103 implements secondary braking. Since the primary brake air supply pressure supplied to the primary brake pump 108 is less than the secondary brake air supply pressure supplied by the secondary brake pump 102. The braking force of the first-stage brake is smaller than that of the second-stage brake, the first-stage brake enables the winch to decelerate without stopping rotation, and the second-stage brake enables the winch to stop rotation.

Setting the falling distance height of a rammer of the dynamic compaction machine and the deceleration braking height before the rammer is not landed in a controller, setting ramming times in the controller, and obtaining a rammer starting execution feedback signal to calculate the current ramming times; setting different deceleration braking heights according to different drop heights; the smaller the drop height is, the smaller the deceleration braking height is; the larger the drop height, the larger the deceleration braking height.

During the free falling process of the rammer in the non-unhooking mode, when the rammer reaches the set deceleration braking height before the rammer is not grounded, namely when the rammer falls freely to the set height before the rammer pit, the controller sends a primary braking instruction, so that the primary braking pump 108 drives the primary braking clamp 105 to brake for primary braking, and the winch cannot be locked. When the rammer lands, namely after the rammer falls freely to the rammer pit, the falling distance height is zero, the rammer lands, the controller sends out a secondary braking instruction, so that the secondary brake pump 102 drives the secondary brake clamp 103 to perform secondary braking, and the winch is locked. Therefore, multi-stage soft deceleration braking of free falling of the rammer of the winch is realized. The design can reduce the impact on the winch and reduce the rope outlet amount of the hoisting steel wire rope of the winch. The controller can judge whether the rammer lands according to the height of the falling distance, and when the height of the falling distance is zero, the rammer lands.

As shown in fig. 1, the free-fall ram deceleration control system of the dynamic compactor in the first embodiment includes a controller, a non-unhooking mode pneumatic control valve 100, a primary brake pump 108, a secondary brake pump 102, a first pneumatic valve 114, a second pneumatic valve 113, a primary exhaust valve 109, a secondary exhaust valve 101; the pilot control air source is communicated with an air inlet of the non-unhooking mode pneumatic control valve (100), and an air outlet of the non-unhooking mode pneumatic control valve (100) is communicated with an air inlet of the first-level height braking electromagnetic air valve (115) and an air inlet of the second-level height braking electromagnetic air valve (116).

The air inlet of the first-level brake pump 108 is communicated with the air outlet of the first pneumatic valve 114, the air outlet of the first-level height brake electromagnetic air valve 115 is communicated with the air inlet of the first-level exhaust valve 109, and the air outlet of the first-level exhaust valve 109 is communicated with the control port of the first pneumatic valve 114; the air inlet of the first pneumatic valve 114 is connected with a primary brake air source;

an air inlet of the secondary brake pump 102 is communicated with an air outlet of the second pneumatic valve 113, an air outlet of the secondary height brake electromagnetic air valve 116 is communicated with an air inlet of the secondary exhaust valve 101, and an air outlet of the secondary exhaust valve 101 is communicated with a control port of the second pneumatic valve 113; the air inlet of the second pneumatic valve 113 is connected with a secondary brake air source;

a first shuttle valve 110 is arranged in a pipeline of the air outlet of the first-level height braking electromagnetic air valve 115 communicated with the air inlet of the first-level exhaust valve 109, and second shuttle valves 111, 112 and 117 are arranged in a pipeline of the air outlet of the second-level height braking electromagnetic air valve 116 communicated with the air inlet of the second-level exhaust valve 101.

The non-unhooking mode pneumatic control valve 100 is opened, the dynamic compactor is opened in a non-unhooking mode, at the moment, the air inlet of the first-level height braking electromagnetic air valve 115 and the air inlet of the second-level height braking electromagnetic air valve 116 are connected with a pilot control air source, and the non-unhooking mode pneumatic control valve 100 can be opened by being controlled by a controller and can be opened manually. In the process of freely falling the rammer in the non-unhooking mode, when the rammer reaches the set deceleration braking height before the rammer is not landed, namely when the rammer freely falls to the set height before the rammer pit, the controller sends a first-level braking instruction to the first-level height braking electromagnetic air valve 115, the first-level height braking electromagnetic air valve 115 is electrified, an air inlet and an air outlet of the first-level height braking electromagnetic air valve (115) are communicated, the first pneumatic valve 114 is opened, and a first-level braking air source enters the first-level braking pump 108 through the first pneumatic valve 114 to drive the first-level braking clamp 105 to perform first-level braking. The braking distance of the second-stage braking can be reduced by the first-stage braking, and the rope outlet amount of a hoisting steel wire rope of the winch after the rammer falls to the ground is reduced.

When the rammer lands, namely after the rammer falls freely to the ramming pit, the falling distance height is 0, the rammer falls to the ground, the controller sends a secondary braking instruction to the secondary height braking electromagnetic air valve 116, the secondary height braking electromagnetic air valve 116 is electrified, so that an air inlet and an air outlet of the secondary height braking electromagnetic air valve 116 are communicated, the second pneumatic valve 113 is opened, and a secondary braking air source enters the secondary braking pump 102 through the second pneumatic valve 113 to drive the secondary braking clamp 103 to perform secondary braking, so that the winch is locked.

As shown in fig. 2, the free-fall ram deceleration control system of the dynamic compactor in the second embodiment differs from that in the first embodiment in that:

the air inlet of the first-stage brake pump 108 is communicated with the air outlet of the first-stage exhaust valve 109, and the air outlet of the first pneumatic valve 114 is communicated with the air inlet of the first-stage exhaust valve 109; the air outlet of the first-level height braking electromagnetic air valve 115 is communicated with the control port of the first pneumatic valve 114; the air inlet of the first pneumatic valve 114 is connected with a primary brake air source; a first shuttle valve (110) is arranged in a pipeline of the air outlet of the first pneumatic valve (114) communicated with the air inlet of the first-stage exhaust valve (109).

As shown in fig. 1 and 2, the oil tank comprises an oil tank, an oil pump 107, a first check valve 106 and a second check valve 104;

an oil outlet of the first check valve 106 is connected with an oil inlet A of the primary braking clamp 105, and an oil inlet of the first check valve 106 is connected with an oil inlet path; an oil outlet B of the primary brake clamp 105 is connected with an oil outlet P of the primary brake pump 108, and an oil return port T of the primary brake pump 108 is connected with an oil return path;

an oil outlet of the second check valve 104 is connected with an oil inlet A of the secondary brake clamp 103, and an oil inlet of the second check valve 104 is connected with an oil inlet path; an oil outlet B of the secondary brake clamp 103 is connected with an oil outlet P of the secondary brake pump 102, and an oil return port T of the secondary brake pump 102 is connected with an oil return path;

hydraulic oil in the oil tank sequentially passes through the oil pump 107 to be divided into two hydraulic oil paths, and the first hydraulic oil path sequentially passes through the first one-way valve 106, the oil inlet A of the primary brake clamp 105, the oil outlet B of the primary brake clamp 105, the oil outlet P of the primary brake pump 108 and the oil return tank T of the primary brake pump 108 to form heat dissipation circulation; the second hydraulic oil path sequentially passes through the second check valve 104, the oil inlet A of the secondary brake clamp 103, the oil outlet B of the secondary brake clamp 103, the oil outlet P of the secondary brake pump 102 and the oil return tank T of the oil return port T of the secondary brake pump 102 to form heat dissipation circulation.

Under the condition that the first-stage braking clamp 105 and the second-stage braking clamp 103 are not braked, the first hydraulic oil path and the second hydraulic oil path are both heat dissipation circulating oil paths, heat dissipation is carried out through an oil tank heat dissipation system, the braking heat dissipation effect is good, and the braking performance is improved.

The techniques not described above are common general knowledge of the skilled person. The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.