SU1742417A1 - Air-hydraulic soil compactor - Google Patents

Abstract

Use: for surface compaction of soils in cramped conditions. Essence: the hydropneumatic impact tamper contains a tamping plate, a housing with radial holes, a firing pin with grooves. Under the head is placed a joint, connected by a hinge with a tamping plate. A control unit with a spool is mounted in the housing. The tamper moving control unit is connected to the housing and includes a spool and a limit switch. The tamper motion control unit is hinged to the power cylinder. The cylinder rod is pivotally connected to the tamping plate. The rammer is equipped with a hollow inertial element and throttles. The case of the power cylinder is made with a groove and a hole in the rod end. The control unit spool is made with an annular groove. The throttle mounted on the control unit can be made adjustable. 1 hp ff, 2 ill.

Description

The invention relates to the field of road building machines intended for the surface compaction of soils in cramped conditions, and may find application in the compaction of bonded and non-bonded soils over large areas.

A hydropneumatic percussion device is known primarily for compacting soils, containing a pressure and discharge lines, a housing with inlets for inlets, draining and distributing the working fluid, a firing pin forming a striker cavity with the hull, an inertial element forming an inertia flexion cavity with the housing, and brisk and body - drain cavity, control valve and tool.

The disadvantage of this impact device is the inability to control the quality of compaction, which reduces the effectiveness of its use in soil compaction.

The closest in technical essence to the present invention is a hydropneumatic impact tamper containing a working member, a tamper movement control unit rigidly connected to the working member and pivotally with a tilt hydraulic cylinder, the stem of which is movably fixed on the tamping plate having a hinge connection to the working member through an intermediate link.

The disadvantages of the known tamper are the uneven loading of the drive,

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caused by the design of the working body, as well as the effect of the gas-release reaction of the pneumatic accumulator on the tamping plate and on the operation of the tamper motion control unit.

The aim of the invention is to improve the reliability of operation and the effectiveness of soil compaction.

The goal is achieved by the fact that a hydropneumatic impact tamper containing a tamping plate, a housing with radial holes, connected to a pressure and drain lines, in which is located a firing pin with grooves forming a cavity of the platoon, drain and control located under the striking junction, is hinged connected to the tamping plate; mounted in the housing; a control unit with a spool; connected to the housing; a tamping movement control unit in the form of a housing with channels for connection to the pressure and drain lines The valve of the working fluid flow distributor and the end switch mounted on the tamping plate and pivotally connected to the body of the tamper control unit of the ram cylinder, the rod of which is pivotally connected to the tamping plate, is provided with a hollow inertial element located in the body covering the upper part of the striker and forming the pneumoaccumulator cavity with the latter, and in the body of the control unit of the working body there are three radial holes connected, respectively, to the drain line w, drain cavity percussion device and throttle control set at blo.ka, wherein the distance between the axes of the holes are connected with the drain line, equal to the length of the spool formed on the surface of the bore.

In addition, a bore with an aperture is made in the case of the power cylinder, which connects the pressure line to the overzol cavity through an adjustable choke, thereby switching the spool of the tamper moving control unit to the second position, and therefore applying the minimum number of strokes to ensure the required density.

The spool chamber of the tamper motion control unit is connected to the pressure thrust chamber through an adjustable choke and limit switch, which allows the tamper speed to be regulated within the limits ensuring the required density,

The throttle installed at the control unit of the working body, made

adjustable, which provides the additional possibility of manually adjusting the impact energy by increasing the driving force of the striker.

FIG. 1 shows the hydropneumatic impact on the tamper in the initial position defined by the extreme upper position of the spool of the tamper movement control unit, general view; Fig. 2 shows the same, in the lowest position of the spool of the tamper motion control block. The hydropneumatic impact tamper consists of a working body 1, which is a two-mass hydropneumatic impact device with a housing 2 with

0 there are movable and stationary elements, a tamper movement control unit 3 rigidly connected to the housing 2, and a power cylinder 4, in the case of which a groove with an aperture 5 is made,

5, the power cylinder 4 is pivotally connected to the tamper movement control unit 3 and the tamping plate 6, which is pivotally connected to the working member 1 through the tappet 7. Limit switch 8 is mounted on the tamping plate 6.

The working body 1 consists of a housing 2, in which the firing pin 9 is located, which forms with the housing a platoon cavity 10 of the striker and a control cavity 11, an inertial element 12, which forms an inertia platoon cavity 15 with the housing 13 and 14 and an opening control cavity 16 spool and having a channel 17, the spool 18 control, forming with

0 by the housing of the control unit 19 of the overhead guard 20 and spool 21 cavities, with a groove 22 on the surface of the spool. The inertial element 12 and the upper part of the striker 23 form a cavity

5 pneumoaccumula torus 24, and the housing 2, the striker 9 and the inertial element 12-drain cavity

25.On the striker 9 there is an end groove.

26 forming a closed control cavity with the end face of the inertia element 12. For supplying and discharging the working fluid, there are a pressure head 27 and a discharge pipe 28. Parallel to the drain line, an adjustable throttle 29 is installed in the control block 19.

5 cavities are connecting pipes 30-32. In case 2, an axial groove 33 is made, press on 1; 34 and 35, drain holes 36 and 37, and also openings 38-44 for supplying a working fluid. In housing 2, a guide sleeve 45 is rigidly mounted, along the surface of which the jigs 7 are mated, and the fingers 46 restrict the movement of the jig 7 and the housing 2 relative to each other.

The tamper moving control unit 3 consists of a body 47, divided by a slide valve 48 into a slide valve 49, an upper turret 50, and two intermediate cavities 51 and 52, and an adjustable spring 53 with an adjusting screw 54 is installed in the slide cavity 49. Channel 55 with a regulating throttle 56 , and the flexible pipe 57, the spool cavity 49 is connected to the end switch 8. The superasol cavity 50 through the channel 58 and the pipe 59 is connected by a groove to the hole 5 of the power cylinder 4, and in the channel 58 there is an adjustable other Scelle 60. The intermediate chamber 51 channel 61 is connected with the pressure line and with the stem cavity 62 of the actuator 4, which through a channel 63, conduit 32 and the control unit 19 is connected with the drain line. The delivery line through channel 64 is connected to the over piston cavity 65 of the power cylinder 4 and channel 66 and pipeline 32 to the drain line, and depending on the position of the spool 18 of the control unit 19, the drain occurs either through the drain hole 37 or through an adjustable choke 29 installed control unit 19 and allowing adjustment of the time for returning the power cylinder 4 to its initial position, at which the operating element 1 is set by it in vertical position. The intermediate cavity 52 by the channel 66 is connected to the over piston cavity 65 and to the drain line, and the channel 63 is connected to the rod cavity 62 and to the drain line. According to valves 67 and 68, depending on the position of the spool 48, the rod 62 and the over-piston 65 of the cavity of the power cylinder 4, they are connected either to the drain or to the pressure line.

Hydropneumatic shock tamper works as follows.

When the operator actuates the drive fluid through the pressure line 27 goes to the working body 1 and the unit 3 controls the movement of the rammer. At the same time, through channel 61 and intermediate cavity 51, the rod cavity 62 is connected to the pressure line, as a result of which the body of the power cylinder 4 is drawn in and sets the working member 1 to its original (vertical) position, Cheoez bore with hole 5. Pipe 59, channel 58 and an adjustable choke 60 of the overzolotnik cavity 50 is connected to the pressure line, and the spool cavity 49 through the channel 55, the adjustable choke 56, the flexible pipe 57 and the limit switch 8 is connected to the drain line, with at that moment is determined by the setting of adjustable throttle 60. When the cylinder body 4 is pulled in, the working fluid is displaced from the piston chamber 65 through the channel 66 and the intermediate cavity 52 into the pipeline 32 and further into the drain line, and 67 68 spool 48 exclude in this position the message of the rod 62 and over piston

5 65 cavities of the power cylinder, respectively, with drain and pressure lines. At this moment, under the action of the pressure of the gas, the pneumatic accumulator 24, the firing pin 9 and the inertial element 12 are in opposition to the false end positions. The working fluid from the pressure line 27 through the axial groove 33 enters the cavity 11 of the control by closing the spool, then through the connecting line 31 into the pinhole cavity 21 and, acting on the valve 18, moves it up to the stop. The holes 41 and 43 overlap along the spool 18, and the working fluid from the overzol cavity 20 through the opening 44, the valve 16 controls the opening of the valve and the channel 17 enters the drain cavity 25, then through the drain hole 36, pipe 32, hole 42, groove 22 the spool and the drain hole 37 into the drain line 5 28. After the stop of the spool 18 into the upper wall of the housing of the control block 19, the working fluid from the pressure head 27 continues to flow into the cavities of the striker 10 and inertial

0 of the element 15. At the same time, the hammer 9 and the inertial element 12 begin to move towards each other, compressing the gas in the pneumatic accumulator 24 (platoon phase). When moving upwards, the firing pin 9 with its wean section divides the axial groove 33 from the control cavity 11 and opens the hole 38, jointly the striking platoon 10 with the connecting pipe 30. At the end of the platoon phase, the lower end of the inertial gland 12 enters the end groove 26 of the striker 9, thus forming a closed control cavity. In this case, the control cavity 11 communicates through the drain hole 36 with the pipe 32. With a further platoon of the striker and the inertial element, the working fluid displaced from the closed cavity 26 through the channel 17, the control opening cavity 16 of the spool and the hole 44 enters the backward hollow cavity 20 and, affecting the top

the end of the spool 18, moves it down (Fig, 2). At the same time, openings 41 and 43 are opened along spool valve 18 and drain hole 37 is closed. From the spool cavity 21, the working fluid through the pipeline

31 enters the control cavity 11, then through the drain hole 36 into the pipeline

32 and through the bore 22 of the spool through the hole 41 and the adjustable choke 29 into the drain line 28. As a result, the pressure line 27, the platoon cavity of the striker 10 and the inertial element 15, the connecting pipe 30, the backward cavity of the spool opening channel 16 17 and a closed cavity 26. Forces due to the pressure of the working fluid on the expansion and upper end platforms of the striker 9

and the inertial element 12, are balanced, and due to the gas pressure in the pneumatic accumulator 24, the latter begin to accelerate (the acceleration phase).

When the striker 9 and the inertial element 12 are dispersed, the cavity 26 and the discharge cavity 25 communicate and form a single cavity into which the working fluid flows from the pressure line 27, the platoon cavities of the striker 10 and the inertial element 15, pipeline 30, the wiper cavity 20, the cavity control 16 opening of the spool and channel 17. Moreover, the active surface area of the striker 9 and inertial element 12 from the side of the combined cavities 25 and 26 is larger than from the side of the cavities 10 and 15 of the platoon. Consequently, when the pressures of the working fluid in these cavities are equal, a large driving force acts on the side of the combined cavities 25 and 26, which, besides the pressure force of the gas in the pneumatic accumulator 24, accelerates the firing pin 9 and the inertial element 12. therefore, large driving forces on its way into the drain line are installed adjustable throttle 29. Therefore, in the acceleration phase, the flow of working fluid from the combined cavities 25 and 26, passing into the drain line through the drain hole 36, t Pipeline 32, spool bore 22 and bore 41 are limited by throttle 29. This allows the impact device to be maintained even if an emergency leak of compressed gas from the pneumatic accumulator 24. In this case, acceleration of the striker 9 and the inertial element occurs only due to force , due to the pressure of the working fluid on their end surfaces from the side of the combined cavities 25 and 26.

At the end of the acceleration phase, the dimple 9 strikes at work 7. In this case, it covers the opening 38 and, with respect to the control cavity 11, disengages from the drain hole 36. At the same time, the axial bore 33 communicates with the control cavity 11 and through the pipeline 31 to the spool cavity 21, into which the working fluid starts to flow from the pressure line 27, the platoon cavities of the striker 10 and the inertial element 15, moving the valve 18 upwards. At the same time, the working fluid is expelled from the insolary cavity 20 through the channel 17, the drain cavity 25, the drain hole 36 and the pipeline 32 into the spool duct 22 and further, depending on the position of the spool 18 through the closing hole 41 or the opening drain 37 to the drain line 28. This is the end of the next duty cycle.

The amount of fluid entering the spool cavity 21 from the die 10 of the strike plate depends on the amount of penetration of the tamping plate 6 into the soil, i.e. on its degree of compaction. The duration of movement of the spool 18 upward to overlap it through the holes 41 and 43 depends on this. The length of movement of the inertial element 12 depends on the duration of movement of the spool 18 upward until it stops completely. At high soil resistances, the introduction of tamping plate 6 is small, therefore, the amount of fluid displaced from cavity 10 of the striker through axial groove 33, control cavity 11 and pipeline 31 into spool cavity 21 is small. The duration of the upward movement of the spool 18 increases, and consequently, the path of the coasting of the inertia element 12 to a stop also increases. At low soil resistances, on the contrary, the amount of penetration of the striker 9 with tamping plate 6 increases. At the same time, a larger volume of fluid is displaced from the striker cavity 10, which enters the spool cavity 21 and reduces the duration of the spool 18 moving upwards, which leads to reduced stick down inertial element 12 to stop.

In the next working cycle, the stroke of the striker 9, and consequently, the energy and frequency of its impacts depend on the amount of overrun of the inertial element 12 in the previous cycle. Since the striker 9 and the inertial element 12 are cocked synchronously, when cocked, they travel the same way and at the end of the cocking they meet at a point located some distance from their original position. The stroke of the hammer is equal to the distance from this meeting point to the point of contact with shaft 7. As the soil resistance increases, the penetration rate of the hammer 9 increases. This means that during the next operating cycle, the spool 18 will have a relatively long travel time, and the inertial element 12 during this time will go a long way before the start of the platoon. Consequently, upon further cocking, the meeting point of the striker 9 and the inertial element 12 shifts away from the soil being compacted. As a result, the striker stroke increases, and hence the energy of the subsequent impact increases. Thus, with a lower soil resistance, a smaller stroke and a smaller impact energy occur, and, conversely, with a higher soil resistance, a larger stroke, and, consequently, a greater impact energy, takes place. In addition, the change in the size of the working stroke of the striker 9 leads to a change in the cycle time of the working body. With smaller values of the working stroke, the platoon and acceleration times of the striker will also be short. This means that at low impact energies, the frequency of their application increases, while at high energies, it decreases. In addition, the frequency change also occurs due to a change in the closure time of the spool 18. Due to the fact that the closure time of the spool depends on the insertion of the striker 9, then with low ground resistance the amount of fluid displaced from the striker cavity 10 is large, time to close the spool is short. This, in turn, leads to a decrease in the cycle time of the percussion device and an increase in the frequency of impacts. On the other hand, as the resistance of the soil increases, the amount of fluid displaced from the die 10 of the striking platoon decreases and the closure time of the spool increases, resulting in a decrease in the frequency of impacts. Thus, as the degree of compaction of the soil changes, the frequency of impacts of the impact device changes in such a way that the greater the resistance of the soil, the lower the frequency of impacts, and vice versa.

Thus, the working body 1 of the hydro-pneumatic impact tamper provides automatic regulation of energy and frequency of impacts, depending on the degree of compaction of the soil, and also increases the drive load.

The achievement of the required density of the soil is determined by the number of impacts of the percussion device on each seal trail. At the same time guaranteed to apply the minimum number of strokes required to obtain the required

density is provided by adjusting the speed of tamper movement. This is done as follows.

In the initial position (Fig. 1), the working fluid 5 from the pressure line 27 through the intermediate cavity 51 of the tamper control unit 3, the channel 61, the rod cavity 62 of the power cylinder 4, the bore with the hole 5, the pipeline 59 and

0, the channel 58 with adjustable throttle 60 enters the suprapolar cavity 50 and, acting on the spool 48, moves it to the lower position, expels the liquid from the spool cavity 49 through channel 55, adjustable throttle 56, flexible pipe 57 and limit switch 8 to the drain line (figure 2). Next, the pressure line through channel 64 is connected to the over piston cavity 65, with the piston cavity 65 above 0, skose 68 being cut off from the drain line. Under the action of the pressure of the working fluid, the body of the power cylinder 4 moves and tilts the working member 1 from the vertical axis of the boom, thereby displacing the working fluid to the drain line through the channels 61 and 63 and the intermediate cavity 51 from the rod end 62, which pressure line. At the end of the working stroke, by pressing the rod of the ram 4, the limit switch 8 is turned on. In this case, the pressure line through the flexible pipe 57, channel 55 and adjustable throttle 56 is connected to the spool valve

5 cavity 49.

The pressure of the working fluid in the spool 49 and suprazolotic cavities 50 is equalized, and by the spring 53 the spool 48 returns to its original position, removing the working fluid from the superzolotnoy cavity 50 through channel 58,. adjustable throttle 60. pipe 59 and bore with hole 5 into the piston crown 65 and then through the opening

5 channel 66 and the intermediate cavity 52 in the drain line. At the same time, the pressure line is connected through channel 51 to the rod cavity 62 of the power cylinder 4, the casing of which is moved by the action of the flow rate of working fluid, returning the working body 1 to its original position (figure 1). Then the cycle repeats.

Due to the fact that the working body 1 is at a certain time tilted,

5 This hydropneumatic impact tamper has the ability to move to a new seal track. Considering that the duration of the switching of the spool 48 from one position to another, and consequently, the response time of the power cylinder 4 depends

from the flow rate of the working fluid entering the supratolar 50 and the spool 49 cavity through adjustable throttles 60 and 56, then by changing the settings of these throttles, you can adjust the speed of tamper movement. In this way, on each trail of compaction, the number of blows required to obtain the required density is ensured.

Soil compaction in the new position is similar.

Claims (2)

Claim 1. Hydropneumatic impact tamper, comprising tamping plate, housing with radial holes, connected to pressure and drain lines, in which is located a firing pin with grooves, which forms pivotally attached to the housing of discharge, drainage and control, pivotally connected to a tamping plate; a control unit with a spool mounted in the housing; a tamper moving control unit connected to the housing; and a housing with channels for connection to the pressure and drain lines; spredelitel working fluid stream and a limit switch, mounted on a tamping plate, pivotally connected to the tamper control unit casing, a ram cylinder, the rod of which is pivotally connected to the tamping plate, is characterized by the fact that, in order to increase the reliability and efficiency of soil compaction, it is equipped with hollow inertial the element covering the upper part of the striker and forming the pneumo-accumulator cavity with the latter, and the throttles, one of which is installed at the control unit 1, parallel to the drain line, and the other is in the body of the tamper moving control unit and is hydraulically connected to the limit switch, the power cylinder body being made with a groove and a hole in the rod cavity, which is connected by a pipeline with the suprasolar cavity of the tamper moving control unit, the spool of the control unit has an annular groove, the length of which is equal to the distance between the axes holes connected to the drain line. 2. Rammer pop. 1, characterized in that the throttle of the control unit is adjustable. 52 # 40 7 ft W v N YV4 NN FIG. I