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EP0447552A1 - Dispositif de frappe - Google Patents

Dispositif de frappe Download PDF

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Publication number
EP0447552A1
EP0447552A1 EP90901091A EP90901091A EP0447552A1 EP 0447552 A1 EP0447552 A1 EP 0447552A1 EP 90901091 A EP90901091 A EP 90901091A EP 90901091 A EP90901091 A EP 90901091A EP 0447552 A1 EP0447552 A1 EP 0447552A1
Authority
EP
European Patent Office
Prior art keywords
housing
chamber
striking
piston
space
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP90901091A
Other languages
German (de)
English (en)
Other versions
EP0447552A4 (en
Inventor
Petr Yakovlevich Fadeev
Vladimir Yakovlevich Fadeev
Vladlen Viktorovich Korobkov
Rim Asmanovich Kulagin
Nikolai Petrovich Ermilov
Andrei Gennadievich Podkorytov
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Institut Gidrodinamiki Imeni Ma Lavrentieva Sibi
Original Assignee
Institut Gidrodinamiki Sibirskogo
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Institut Gidrodinamiki Sibirskogo filed Critical Institut Gidrodinamiki Sibirskogo
Publication of EP0447552A1 publication Critical patent/EP0447552A1/fr
Publication of EP0447552A4 publication Critical patent/EP0447552A4/de
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D17/00—Details of, or accessories for, portable power-driven percussive tools
    • B25D17/28—Supports; Devices for holding power-driven percussive tools in working position
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D17/00—Details of, or accessories for, portable power-driven percussive tools
    • B25D17/24—Damping the reaction force
    • B25D17/245—Damping the reaction force using a fluid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D9/00—Portable percussive tools with fluid-pressure drive, i.e. driven directly by fluids, e.g. having several percussive tool bits operated simultaneously
    • B25D9/14—Control devices for the reciprocating piston
    • B25D9/145—Control devices for the reciprocating piston for hydraulically actuated hammers having an accumulator

Definitions

  • the present invention relates to force pulse systems which are used to generate force pulses of a specific frequency and intensity, which act on a medium to be processed for the purpose of changing its shape, in particular it relates to a striking device for generating high-performance impact pulses.
  • a percussive device for generating percussion impulses acting on a medium for the purpose of changing its shape (SU, A, 761652) is known, which device is installed on a work machine and contains a percussion mechanism, a longitudinal slide valve device and a work tool.
  • a piston with a two-sided piston rod is arranged to be able to move back and forth.
  • One end of the piston rod is located in the first cavity, while the other end cooperates with the working tool intended for changing the shape of the medium to be processed.
  • the piston divides the second cavity into a pressure chamber, which is connected to the liquid medium source by a pressure line, and an overflow chamber, which is always connected to a drain line and periodically in communication with the pressure chamber.
  • a spring-loaded slide element is arranged in the housing of the longitudinal slide valve device and divides the cavity of the housing of this valve device into two chambers. The first chamber is always connected to the drain line, while the second chamber is always in communication with the overflow space and periodically with the pressure chamber of the impact mechanism.
  • the known device works as follows.
  • the piston and the working tool assume the end position to be extended to the medium to be processed under the effect of the gas medium pressure in the first cavity.
  • the overflow and the pressure chamber of the impact mechanism are isolated from each other by means of the longitudinal slide valve device.
  • the piston makes a progressive movement in the direction away from the medium to be processed by additionally compressing the gas medium located in the first cavity.
  • the liquid medium is displaced freely from the overflow space of the impact mechanism for the outflow. The movement mentioned lasts until the piston covers with its cylinder surface a hole in the housing wall which connects the overflow space to the drain line.
  • the piston executes a working stroke by starting, at the end of which the piston interacts via its piston rod with the working tool, which transmits a percussion impulse to the medium to be processed.
  • the longitudinal slide valve device is in the open position (that is, in such a position in which the second chamber has the maximum volume) due to a pressure drop of the liquid medium in the Overflow and the pressure chamber connecting channel held.
  • the known striking device has a relatively high efficiency. Furthermore, this device is characterized by the simple construction of its main elements. However, the known device is attached to the manipulator of the working machine with the aid of steep articulated elements which do not ensure absorption of the energy of the dynamic action on the impact mechanism and the working machine on the part of the medium to be processed. As a result, the dynamic loads of the known device at "oblique blows" and “empty blows" reach inadmissible values, which reduces the reliability and service life of the device.
  • the working tool in the end position extended to the medium to be processed, interacts directly with the housing of the striking mechanism, and if there is a medium of very low strength to be processed in front of the working tool, the working tool will collide hard with it Impact mechanism housing possible, which is accompanied by the creation of high dynamic loads.
  • the volume of the overflowing liquid increases significantly with the increase in the energy of a single blow, which requires an increase in dimensions or a change in the design of the longitudinal slide valve device in order to maintain constant efficiency.
  • the overflow of the liquid medium from the pressure into the overflow space of the percussion mechanism takes place only via the longitudinal slide valve device, and this fact prevents the creation of a series of striking devices with a high degree of unification.
  • the present invention is based on the object of a striking device with such a structural design of the striking mechanism, with a design of the hydraulic connections of the same with the longitudinal slide valve device and with a design of the resilient connections of the working tool with the striking mechanism and the latter with the working machine, which would make it possible to increase the reliability of both the actual device and the working machine as a whole.
  • the striking device for generating impact pulses acting on a medium to be processed for the purpose of changing its shape which device is installed on a work machine and a striking mechanism in its housing, which has two mutually insulated cavities which the first is filled with a pressurized gas medium and the second cavity with a liquid medium source is connected, a piston with a two-sided piston rod is arranged to be able to move back and forth, one end of which is located in the first cavity and the second end of which cooperates with a working tool intended for changing the shape of the medium to be processed, the piston forming the second cavity in a pressure chamber , which is connected to the liquid medium source by a pressure line, and divides an overflow space, which is always and periodically in communication with a discharge line, and contains a longitudinal slide valve device, in the housing of which a spring-loaded slide element is arranged, which the Divides the cavity of the housing of the valve device into two chambers, of which the first is always connected to the drain line, while the second chamber is always connected
  • Equipping the striking mechanism with a means for ensuring its resilient-elastic connection to the working machine creates the possibility of limited longitudinal displacement of the striking device relative to the working machine and the possibility of its limited angular rotation in all vertical planes passing through the longitudinal axis of the device.
  • the aforementioned limited displacements of the striking device in space are accompanied by a compression of the liquid medium which fills the interior of the means of the resilient-elastic connection, and by forces arising for this reason, which are applied to the housing of the striking mechanism and counteract said displacements .
  • connection of the first chamber of the longitudinal slide valve device to the drain line via an annular recess in the overflow space ensures a constant connection of the first chamber of the longitudinal slide valve device to the drain line regardless of the position of the piston in the impact mechanism, which excludes the possibility of accidental adjustment of the slide element .
  • the means for ensuring a resilient-elastic connection of the striking mechanism to the working machine is an annular housing, which is arranged concentrically with the housing of the striking mechanism and is rigidly connected to it, with a spherical lateral surface in which a closed annular space is embodied, which is carried out by means of a channel a built-in check valve in connection with the pressure chamber, and contains at least three uniformly attached to the circumference on each end face of the annular housing, each of which its piston rod is arranged substantially parallel to the axis of the housing of the impact mechanism, protrudes outwards and cooperates with the inner surface of the corresponding end face of a ring socket which surrounds the housing of the said means and is arranged on the housing of the striking mechanism so as to be longitudinally displaceable, the piston chamber of each hydraulic cylinder however, is connected to the closed annular space via a throttling means, while the piston rod space is connected to the overflow space of the impact mechanism by means of a channel.
  • the design of the housing of the means for ensuring a resilient-elastic connection of the striking mechanism with the working machine in the form of a ring with a spherical outer surface enables the longitudinal displacement and angular rotation of the means and the housing of the striking mechanism rigidly connected to it within the two enclosing Ring setting in all planes that run through its longitudinal axis.
  • the closed annular space within the annular housing of said means makes it possible to most efficiently connect the piston spaces of the hydraulic cylinders attached to each end face of the annular housing to one another and to the pressure space.
  • the connection of the annular space to the piston space of each hydraulic cylinder by means of a throttle means ensures that the resistance forces are approximately constant against any displacement of the means relative to the surrounding ring frame and that these forces are independent of the amount of displacement.
  • the connection of the annular space of the medium through channels to the pressure and the overflow space of the striking mechanism guarantees a constant filling of the annular space with the liquid medium and a constant change during the operation of the striking mechanism.
  • each hydraulic cylinder has an interior space that is connected to the piston chamber.
  • the ring holder has the shape of a stepped cylinder, which faces the working tool with the end face of smaller diameter.
  • the longitudinal slide valve device on the pressure line, which connects the pressure chamber of the percussion mechanism with the liquid medium source, and to arrange a hydropneumatic accumulator with a stepped piston, which is arranged in a reciprocating manner in the housing, parallel to the device on the pressure line the cavity of the case this memory into one with the first
  • the cavity of the impact mechanism always connects the gas space and a fluid space that is always connected to the liquid medium source, the ratio of the area of the face of the stepped piston delimiting the fluid space to the area of the face of the stepped piston delimiting the gas space being smaller than the ratio of the area of the face delimiting the pressure space in the impact mechanism End face of the piston for the area of the end face of the piston rod of the piston mentioned in the first cavity of the striking mechanism.
  • Such an arrangement of the aforementioned elements makes it possible to separate the liquid medium source from the pressure chamber of the striking mechanism during the working stroke and to accumulate a supply of the liquid medium which is unusable during the working stroke in the liquid chamber of the hydropneumatic accumulator with subsequent use of this medium when the piston of the striking mechanism is re-opened.
  • a stepped piston with the aforementioned ratio of the cross-sectional areas of its larger and smaller step is used in the hydropneumatic accumulator makes it possible to fill the accumulator with the gas medium under a pressure which is equal to the gas medium pressure in the first cavity of the impact mechanism. The easiest way to ensure this is to connect the gas space of the hydropneumatic accumulator directly to the first cavity of the impact mechanism by means of the channel.
  • the construction is simplified and the reliability of the striking device as a whole is increased.
  • the longitudinal slide valve device on the pressure line, which connects the pressure chamber of the percussion mechanism with the liquid medium source, and to arrange at least one additional valve in series with the device on the pressure line, the antechamber of which with the liquid medium source is connected via the longitudinal slide valve device, while the rear space is connected to the pressure chamber and is periodically connected to the overflow chamber of the impact mechanism.
  • the variant of the striking device described above can be further perfected if the longitudinal slide valve device is installed parallel to the pressure line and at least one additional valve is arranged parallel to it, the anteroom of which is periodically connected to the pressure or drain line via the longitudinal slide valve device stands, while the back space is always in connection with the pressure line and periodically in connection with the overflow space of the impact mechanism.
  • a recess is provided in the stepped piston of the hydropneumatic accumulator on the side facing the gas space, in which a pneumatic cylinder is arranged coaxially and rigidly, the piston rod of which is rigidly connected to the stepped piston, and the piston chamber of which is connected to the via a suction valve Is connected to the environment and is connected via a first pressure valve to the piston rod space of the pneumatic cylinder, which piston rod space is connected to the first cavity of the impact mechanism via a second pressure valve.
  • the pneumatic cylinder described above ensures the movement of the stepped piston of the hydropneumatic accumulator, the suction of the gas medium from the surrounding space, the two-stage compression and the pressing of the same into the first cavity of the impact mechanism, whereby the leakage of the gas medium from the first cavity is compensated for possible leaks becomes.
  • the hydropneumatic accumulator prefferably has a safety valve which is designed in the form of a sprung, controlled slide which is accommodated in the housing of the hydropneumatic accumulator, the control chamber of the slide being in communication with the gas space of the hydropneumatic accumulator.
  • a blind annulus offers the possibility, with smaller transverse dimensions of the housing of the striking mechanism, to ensure a low hydraulic resistance against the overflow of the liquid medium during the working stroke and thereby to increase the efficiency of the striking device.
  • the hydraulic shock absorber of the working tool is a bushing, which is arranged in the housing of the striking mechanism with the possibility of a reciprocating movement coaxial to the housing, comprises the working tool and has a recess on its cylindrical outer surface which is in line with the wall of the Housing of the striking mechanism forms a blind annular chamber, which is divided by an annular projection on the inner surface of the housing of the striking mechanism into two parts which communicate with one another via an annular gap, one of which, which faces the medium to be processed, communicates with the drain line stands, while a stop is formed on the working tool on the side of the face of the bushing facing the medium to be machined, which contacts the bushing in the interaction of the work tool with the medium to be processed, being on the other side
  • Forehead of the socket with fixing elements contacting it are arranged to be longitudinally displaceable relative to the working tool in the housing of the striking mechanism, which fixing elements with the working tool cooperate in a "blank space".
  • the striking device designed in accordance with the invention contains a striking mechanism 1 (FIG. 1) and a longitudinal slide valve device 2.
  • the housing 3 of the striking mechanism 1 is divided into two cavities that are insulated from one another: a first cavity 4 that contains a pressurized gas medium is filled, and a second cavity 5, which is always connected to a liquid medium source 6.
  • a piston 7 with a bilateral piston rod 8 is arranged in the housing 3 so that it can be moved back and forth along the axis.
  • One end 9 of the piston rod 8 is located in the first cavity 4, the second end 10 interacts with a work tool 11 which is intended to change the shape of a medium to be processed.
  • the piston 7 divides the second cavity 5 of the impact mechanism 1 into a pressure chamber 12 and an overflow chamber 13.
  • the pressure chamber 12 is always connected to the liquid medium source 6 by means of a channel 14 in the housing 3 and a pressure line 15, while it is connected by means of a channel 16, one Hydraulic line 17 and a line 18 parallel to this is connected to the longitudinal slide valve device 2, the housing 19 of which is divided by a spring-loaded slide element 20 into a first and a second chamber 21 and 22, respectively.
  • the overflow space 13 is always connected to the by means of a channel 24 and a drain line 25 via an annular recess 23, which is carried out on the inner surface of the housing 3 of the impact mechanism 1 Drain in connection, while it is always connected to the first chamber 21 of the longitudinal slide valve device 2 by means of a channel 26 and a hydraulic line 27.
  • the overflow space 13 is connected by means of a hydraulic line 29 to the housing 19 of the longitudinal slide valve device 19 by means of a channel 28 which (as seen in the axial direction) is closer to the first cavity 4 of the housing 3 than the annular recess 23, while it is connected by means of a channel 30 is connected via a check valve 31 to the housing 19 and the second chamber 22 of the longitudinal slide valve device 2.
  • the striking mechanism 1 is provided with a means 32 for ensuring a resilient-elastic connection thereof to the working machine .
  • the means 32 is rigidly attached to the housing 3 of the striking mechanism 1 in a plane perpendicular to its longitudinal axis and extending through the striking center 0.
  • the means 32 contains an annular housing 33 with a spherical outer surface 34, which is arranged concentrically with the housing 3 of the striking mechanism.
  • a closed annular space 35 (FIG. 2) is embodied in the annular housing 33, which is always filled with the liquid medium which is discharged from the pressure chamber 12 ( 3) arrives via a channel 36 with a check valve 37 installed in it.
  • At least three hydraulic cylinders 38 are arranged uniformly on the circumference and parallel to the axis of the housing 33 on the two end faces of the annular housing 33 (FIG. 1).
  • the piston rods 39 of each hydraulic cylinder 38 protrude outwards and interact with the inner surface of the corresponding end face of a ring mount 40, which encloses the annular housing 33 of said means 32.
  • each hydraulic cylinder 38 is always connected to the closed annular chamber 35 via a throttle means 42 (FIG. 4), for example via a throttle bore.
  • the piston rod chamber 43 is always connected to the overflow chamber 13 by means of channels 44 via the annular recess 23.
  • the hydraulic cylinders 38 are arranged in pairs coaxially and symmetrically with respect to the annular space 35.
  • the piston rod 39 (FIG. 4) of each hydraulic cylinder 38 has an inner cavity 45 which is connected to the piston chamber 41, as a result of which the volume of the annular space 35 filled with the liquid medium is significantly increased, which is necessary to increase the efficiency of the means 32.
  • the ring holder 40 (FIG. 1) has the shape of a stepped cylinder which faces the working tool 11 with the end face of smaller diameter. Such a form of the ring holder 40 ensures in the best possible way that it is accommodated in the means 32 and offers the possibility of protecting the striking mechanism 1 against overloads.
  • the working tool 11 is arranged in the axial rotation of the housing 3 of the striking mechanism 11 on the side of its end face facing the medium to be processed, with the possibility of a limited reciprocating movement along the axis. In the axial direction, the working tool 11 cooperates with the housing 3 of the impact mechanism via a hydraulic shock absorber 46.
  • the hydraulic shock absorber 46 consists of a movable along the axis of the housing 3 of the impact mechanism 1 and the work tool 11 from the outside cylindrical sleeve 47, which has an annular recess 48 on the cylindrical outer surface.
  • the annular recess 48 forms, together with the side surface of an axial recess 49, a blind annular chamber 50.
  • An annular projection 51 is implemented on the inner side surface of the axial recess 49 in the housing 3.
  • the annular projection 51 divides the blind annular chamber 50 into two parts 53 and 54 which communicate with one another via an annular gap 52.
  • the part 54 of the blind annular chamber 50 facing the medium to be processed is connected to the drain line 25 by means of a channel 55 in the housing 3 and a hydraulic line 56 always in touch.
  • the bushing 47 With its forehead facing the medium to be processed, the bushing 47 cooperates in the axial direction with the stop 57 of the working tool 11, while with its other forehead it is supported against fixing elements 58 which are movable along the axis of the housing 3 and the working tool 11.
  • At least one recess 59 is provided on the side surface of the working tool 11 on the side of the pressure chamber 12, the side surface of which contacts the aforementioned fixing elements 58, while the end face of the recess with the fixing elements 58 on the side of the end surface 60 of the working tool 11 during movement of the working tool 11 cooperates in the direction of the medium to be processed.
  • the work of the striking device designed according to the invention takes place in the following manner.
  • the piston 7 (FIG. 1) assumes the end position in the first cavity 4 of the striking mechanism 1 under the action of the compressed gas medium on its end face 9 in the first cavity 4 of the impact mechanism 1 and makes contact with its end face 10 with the end face 60 of the Working tool 11, which is supported against the surface of the medium to be processed.
  • the sprung slide element 20, the Piston rods 39 of the means 32 to ensure a resilient-elastic connection, the check valves 31 and 37, the bushing 47, the stop 57 and the fixing elements 58 assume the position shown in FIG. 1.
  • the piston 7 moves by overcoming the gas medium pressure in the first cavity 4 of the impact mechanism 1, away from the medium to be processed.
  • the liquid medium is freely displaced from the overflow space 13 via the ring-shaped recess 23, the channel 24 and the drain line 25 to the drain.
  • the piston 4 is pulled open.
  • the piston 7 covers with its cylindrical surface the annular recess 23 and isolates the overflow space 13 from the drain line 25.
  • the impulse of which via the channel 28 Hydraulic lines 29 and 30 under the action of the check valve 31 is transferred into the second chamber 22 of the longitudinal slide valve device 2 acts on the spring-loaded slide element 20 and adjusts it in the direction of the first chamber 21 until it stops.
  • the liquid medium is freely displaced from the first chamber 21 via the hydraulic line 27, the channel 26, through the annular recess 23 and then via the channel 24 and the drain line 25 to the drain.
  • the first chamber 21 of the longitudinal slide valve device 2 is always connected to the annular recess 23, the free outflow of the liquid medium from the first chamber 21 and consequently the adjustment of the slide element 20 is possible even if the annular recess 23 is covered by the side surface of the piston 7.
  • the spring-loaded is set Slide element 20 connects the pressure chamber 12 and the liquid medium source 6 to the overflow chamber 13 via the channel 16, the hydraulic lines 17 and 29 and the channel 28.
  • the pressure chamber 12 is connected to the second chamber 22 of the longitudinal slide valve device 2 via the channel 16 and the hydraulic line 18.
  • the pressure in the overflow chamber 12 and in the overflow chamber 13 also increases as a result of an increase in the hydraulic resistance to the overflow of the liquid medium via the line, which the pressure chamber 12 via the line 18, the throttle means 61 and Line 27 connects at the beginning of the stroke with the drain.
  • the piston 7 releases the annular recess 23 and connects the overflow space 13 to the drain line 25 again via the channel 24.
  • the pressure of the liquid medium in the overflow space 13 decreases and becomes the same Discharge pressure.
  • the liquid medium pressure in the pressure chamber 12 continues to increase monotonously with the increase in the speed of the working movement of the piston 7 and the associated hydraulic resistance to the overflow of the liquid medium from the pressure chamber 12 into the overflow chamber 13 via the hydraulic lines 17 and 29.
  • the release of the annular recess 23 basically takes place at the beginning of the working stroke of the piston 7.
  • the hydraulic lines 17 and 29 are connected to one another and the pressure chamber 12 is connected to the second chamber 22 of the longitudinal slide valve device 2 via the hydraulic line 18.
  • the liquid medium which has entered the second chamber 22 of the longitudinal slide valve device 2 via the hydraulic lines 29 and 30 is passed through the throttle means 61 present in the spring-loaded slide valve 20 via the hydraulic line 27, the channel 26, the annular recess 23, the channel 25 and the drain line 25 for the drain.
  • the slide element 20 under the action of the spring 62 strives to return to its original position.
  • the throttling means 61 Thanks to the rationally chosen small dimensions of the throttling means 61, the prevention of the liquid throughput for the outflow from the second chamber 22 via the hydraulic lines 30 and 29 due to the existing check valve 31, and the fact that the liquid medium into the second chamber 22 from the pressure chamber 12 via the Hydraulic line 18 flows in, however, the speed of movement of the spool element 20 in the direction of the second chamber 22 is so low that the spool element 20 does not come to separate the hydraulic lines 29 and 17 and the hydraulic line 18 until that moment shut off, since the speed of the piston 7 is sufficient to ensure in the pressure chamber 12 and consequently in the hydraulic line 18 and in the second chamber 22 of such a liquid medium pressure that is required to overcome the force of the spring 62. In the manner described above, a reliable retention of the slide element 20 in the first chamber 21 is ensured, which allows the piston 7 to move freely along the entire length of the working stroke in the direction of the medium to be processed.
  • Retaining the slide element 20 in the first chamber 21 is made considerably easier if the check valve 31 is installed in the hydraulic line 30 and prevents the liquid from flowing out of the second chamber 22 via the lines 30 and 29 at the moment when the speed of the piston 7 has not yet reached a value which is necessary for ensuring a liquid medium pressure in the pressure chamber 12, in the hydraulic line 18 and in the second chamber 22 which is sufficient for overcoming the force of the spring 62.
  • the piston 7, with the end face 10 of its piston rod 8 strikes the end face 60 of the working tool 11 supported against the medium to be processed, by transmitting an impact pulse to the medium to be processed and thereby performing the useful work.
  • the piston 7 comes to a standstill, as a result of which the overflow of the liquid medium from the pressure chamber 12 into the overflow chamber 13 via the hydraulic lines 17 and 29 ceases and the pressure gradient between the said chambers 12 and 13 becomes zero.
  • the liquid medium pressure in the second chamber 22 drops and becomes equal to the discharge pressure.
  • the slide element 20 returns to the starting position under the action of the spring 62 and displaces the liquid medium from the second chamber 22 through the throttle means 61 via the hydraulic line 27 into the drain line 25.
  • the above-mentioned deviations are accompanied by the occurrence of additional, extremely undesirable dynamic loads of high intensity applied to the striking mechanism 1 and the working machine, which not only reduce the reliability and service life of the same, but can also lead to breaks and malfunctions.
  • the striking device according to the invention is equipped with additional means which allow to prevent harmful consequences of the deviations from normal operation.
  • the working tool 11 When interacting with the medium to be processed, in this case, the working tool 11 has a dynamic force that is considerable in terms of size and perpendicular to the axis of the striking mechanism 1, in addition to the axial impact reaction.
  • the force mentioned generates a dynamic torque of considerable size, which loads the housing 3 of the striking mechanism 1 and is transmitted to the working machine via the kinematic connection.
  • the liquid medium flows from its source 6 via the channel 16 and the hydraulic lines 17 and 36 through the check valve 37 into the annular housing 33 of the means 32 and fills the annular space 35, whereupon it passes through the throttle means 42 into the piston chambers 41 of the hydraulic cylinders 38.
  • the piston rods 39 of the hydraulic cylinders 38 assume the end position extended from the annular housing 33 and are supported with their free end faces against the inner surfaces of the corresponding end faces of the ring holder 40.
  • the housing 33 of the means 32 assumes a position which is coaxial and symmetrical with respect to the larger step of the said socket 40.
  • the elastic compression of the liquid medium in the closed annular space 35 is accompanied by an increase in the hydraulic pressure in the latter and, as a result, by the occurrence on the piston rods 39 of axial forces which are opposite to the aforementioned axial reactions on the part of the annular mount 40 and the movement of the Counteract piston rods 39 inside said housing 33 of means 32. Under the action of these forces, the movement of the housing 3 in the direction of the medium to be processed is slowed down and the subsequent stopping the same. The work of the counteracting axial forces on the path of movement of the housing 3 is converted into the potential energy of the elastically compressed liquid medium which fills the closed annular space 35.
  • the movement size of the piston rods 39 and the volume of the liquid medium in the annular space 35 are selected such that the total size of the piston rods 39 and via the ring holder 40 the working machine applied opposing axial forces equal to or less than a predetermined limit permissible according to the strength.
  • the braking of the housing 3 of the impact mechanism 1 is most effective when the counteracting axial forces which are applied to the piston rods 39 by the liquid medium in the annular space 35 have a constant value.
  • this is achieved in that the piston chamber 41 of each hydraulic cylinder 38 is connected to the closed annular chamber 35 via the throttle means 42.
  • the movement quantities of the piston rods 39 and the axial forces counteracting their movement reach a maximum.
  • the piston rods 39 move in the opposite direction after stopping, by returning the housing 3 of the striking mechanism 1 to the original position.
  • the throttle means 42 limits the throughput of the liquid medium from the closed annular space 35 into the piston space 41 of the hydraulic cylinders 38 by reducing the speed of movement of the piston rods 39 and thereby possible collisions of the elements of said means 32 during the Return prevented.
  • the agent works in the manner described above.
  • At least one piston rod 39 on the front end facing the first space 4 and at least a piston rod 39 on the end of the annular housing 3 of the means 32 facing the medium to be processed cooperates with the ring holder 40, and from the latter side the same forces are applied to the movement of the piston rods 39 in the direction of the closed annular space 35 effect, which in turn causes the creation of axial forces which counteract the aforementioned movement of the piston rods 39.
  • the force applied to the working tool 11 (FIG. 1), which is perpendicular to the axis of the striking mechanism 1, can exceed the computational force in terms of size.
  • the predetermined stroke of the piston rods 39 in the hydraulic cylinders 38 of the means 32 may be insufficient to ensure the force required in terms of size, which counteracts the rotation of the housing 3 of the striking mechanism 1.
  • the described case is prevented in that the ring holder 40 of the means 32 has the shape of a stepped cylinder, with its smaller end surface facing the medium to be processed, which ring holder has its inner side surface 40a with the outer surface of the Housing 3 of the impact mechanism 1 cooperates by the Angle of rotation of the latter around the center of impact 0 is limited in the predetermined range and thereby precludes hard support of the piston rods 39 against the bottom of the hydraulic cylinders 38.
  • the striking device according to the invention interacts with a medium of very low strength to be processed, then a considerable part of the energy of the piston 7 of the striking mechanism 1 performing the working stroke is converted into the kinetic energy of the working tool 11 (FIG. 1), and the latter comes moving towards the medium to be processed.
  • the working tool 11 acts on the fixing elements 58 on its side surface by means of the end surface of the recess 59 which is closer to the end surface 60 and which in turn set the cylindrical bushing 47 in motion along the axis.
  • the liquid medium that fills the annular chamber 50 between this bushing 47 and the housing 3 of the striking mechanism 1 passes through the bushing 47 from the part 53 via the annular gap 52 into the part 54 displaced this annular chamber 50. Due to a high hydraulic resistance of the aforementioned annular gap 52, a high liquid medium pressure is generated in the part 53 of the annular chamber 50, which acts on the bushing 47 and the work tool 11 connected to it at the moment via the fixing elements 58 and reduces the speed of movement thereof to zero , wherein the kinetic energy of the work tool 11 is converted into the thermal energy of the liquid.
  • the working tool 11 is supported on its side surface with the end surface of the recess 59, which is remote from its end surface 60, against the fixing elements 58, which in turn are supported against the end surface of the axial recess 49 in the housing 3.
  • the working tool 11, the cylindrical bushing 47 and the fixing elements 58 assume a position shown in FIG. 1 and are again ready for operation as described above.
  • the absorption of the kinetic energy of the work tool 11 in the predetermined computational way allows the process of the interaction of the work tool 11 with the housing 3 to be extended in time and to exclude the possibility of the creation of impermissible dynamic loads which are impermissible in terms of size, which affects the reliability and service life of the impacting device and the working machine has a favorable effect.
  • a hydropneumatic one Arrange memory 64 In the housing 65 of this accumulator 64, a stepped piston 66 is arranged to be able to move back and forth, which divides the cavity of the housing 65 into a gas space 67 and a liquid space 68.
  • the ratio of the surface area of the end face 69 delimiting the hydraulic space 68 of the stepped piston 66 to the area of the end face 70 delimiting the gas space 67 of the stepped piston 66 is smaller than the ratio the end face 71 of the piston 7 delimiting the pressure chamber 12 in the striking mechanism 1 is selected for the area of the end face 9 of the piston rod 8 of the piston 7 located in the first cavity 4 of the striking mechanism 1.
  • the striking device using the hydropneumatic accumulator 64 functions similarly to the embodiment of the device shown in FIG. 1. The difference is that at the moment of the connection of the pressure chamber 12 (FIG. 6) and the overflow chamber 13 of the striking mechanism 1 via the hydraulic lines 17 and 29, the slide element 20 isolates the liquid medium source 6 from the pressure chamber 12 at the same time as the piston 7 is working . During this time, the liquid medium flows from the source 6 via the hydraulic line 73 into the liquid space 68 of the hydropneumatic accumulator 64 and, by moving the step piston 66 thereof, displaces the gas medium contained in its gas space 67 via the line 72 into the first cavity 4 the striking mechanism 1.
  • the liquid medium flows out of the liquid space 68 of the Hydropneumatic accumulator 64 under the effect of the pressure of the gas medium contained in the gas chamber 67 via the hydraulic line 73 through the longitudinal slide valve device 2 and via the hydraulic line 17 into the pressure chamber 12 of the impact mechanism 1 and together with the liquid medium source 6 guides the lift of the piston 7 out. Thanks to the fact that in the described variant of the device the liquid medium from the source 6 is not pushed through for the outflow during the working stroke of the piston 7 but is accumulated in the liquid space 68 of the hydropneumatic accumulator 64, the efficiency of the striking mechanism 1 increases significantly.
  • a compensation of the escape of the gas medium from the first cavity 4 of the striking mechanism 1 is made possible by a pressure medium in the form of an additional pneumatic cylinder 74 (FIG. 7), which is built into the hydropneumatic accumulator 64.
  • a recess is carried out in the stepped piston 66 on the side facing the gas space 67, in which the pneumatic cylinder 74 is arranged coaxially and is rigidly fastened.
  • the piston rod 75 of this pneumatic cylinder 74 is rigidly connected to the smaller step of the step piston 66.
  • the piston chamber 76 of the pneumatic cylinder 74 is connected to the environment via a channel 77 through a suction valve 78.
  • the piston rod chamber 79 of the pneumatic cylinder 74 is connected to the piston chamber 76 by means of a channel 80 in its housing via a first pressure valve 81 and is connected to the first cavity 4 of the striking mechanism 1 by a second pressure valve 82 via a channel 83 and the line 72.
  • a safety valve is installed in the housing 65 of the hydropneumatic accumulator 64, which is in the form of a cushioned, pneumatically controlled slide 84, the control chamber of which is connected via channels 86 and 87 in the housing 65 to the gas chamber 67 of the hydropneumatic accumulator 64 and via channels 88 and 83 to the line 72.
  • the striking device using the pneumatic cylinder 74 functions as follows.
  • the liquid medium source is isolated from the pressure chamber 12 of the striking mechanism 1, and the liquid medium flows via the hydraulic line 73 into the liquid chamber 68 of the hydropneumatic accumulator 64 by moving its stepped piston 66 in the direction of Gas space 67 moves.
  • the piston rod 75 (FIG. 7) of the pneumatic cylinder 74 rigidly connected to it moves in the same direction.
  • the piston 89 attached to the end of the piston rod 75 compresses the gas medium in the piston chamber 76, which passes through the channel 77 through the first pressure valve 81 passes through the channel 80 into the piston rod chamber 79.
  • the hydropneumatic accumulator 64 works together with the liquid medium source 6, and its stepped piston 66 moves in the direction of the liquid chamber 68 by displacing the liquid medium therein into the pressure chamber 12 of the striking mechanism 1 .
  • the piston rod 75 rigidly connected to the stepped piston 66 moves in the same direction and, with its piston 89, displaces the gas medium with additional compression of the same from the piston rod chamber 79 via the channel 80 through the second pressure valve 82 through the channel 83 and the line 72 into the first cavity 4 of the impact mechanism 1.
  • the gas medium which has entered the piston chamber 76 during suction in the manner described above is pressed into the first cavity 4 of the impact mechanism 1. If the gas medium pressure in the first cavity 4 of the impact mechanism 1 does not drop due to leakage through the leaks, the spring-loaded and pneumatically controlled slide 84 assumes, under the effect of the gas medium pressure in the gas chamber 67, the end position on the left in the drawing, in which the channel 80 and the Piston rod chamber 79 of the compressed air cylinder 74 are always connected to the environment via a channel 90 in the housing 65. In this case, the gas medium is not pressed into the first cavity 4 of the impact mechanism 1.
  • the striking device works in the manner described above and the difference is that the liquid medium into the pressure chamber 12 of the striking mechanism 1 via the longitudinal slide valve device 2 and at least one additional valve 91, which are arranged one behind the other on the pressure line 15, flows in.
  • the closure element 94 of the valve 91 separates the hydraulic lines 17 and 29 from one another by isolating the pressure chamber 12 and the overflow chamber 13 from one another.
  • the liquid medium from the source 6 flows through the pressure line 15 through the axial bore 95 in the closure element 94 through the hydraulic line 17 into the pressure chamber 12 of the striking mechanism 1 and ensures the lift of the piston 7.
  • the antechamber 92 of the additional valve 91 is connected to the overflow space 13 via the hydraulic lines 15 and 96, and the closure element 94 moves by the action of the liquid medium in the pressure chamber 12 while overcoming the force of the spring 97 in the direction of the antechamber 92 and connecting the pressure chamber 12 and the overflow chamber 13 of the percussion mechanism 1 via the hydraulic lines 17 and 29.
  • the working stroke of the piston 7 takes place.
  • the slider element 20 and the closure element 94 are held in the open position in the manner described above Wise.
  • An essential difference of the striking device according to the invention described in this case is that the overflow of the liquid medium from the pressure chamber 12 into the overflow chamber 13 during the working stroke of the piston 7 while avoiding the longitudinal slide valve device 2 through at least one additional valve 91 happens, which on the one hand significantly simplifies the geometry of the hydraulic line via which the overflow takes place and on the other hand enables a substantial increase in its transverse mass. As a result, the hydraulic resistance can be significantly reduced and consequently the efficiency of the impact mechanism 1 can be increased.
  • the longitudinal slide valve device 2 is arranged on the pressure line 15 and When eliminating an overflow of the liquid medium through it between the spaces 12 and 13 mentioned during the working stroke of the piston 7, it is therefore possible on the one hand to significantly reduce the geometric dimensions of the longitudinal slide valve device 2 and on the other hand - with a constant output of the liquid medium source 6 - To use the longitudinal slide valve device 2 of the same type for striking devices with different single impact energy.
  • valve 91 instead of just one additional valve 91, two or more valves of the same size can be installed on the hydraulic lines 17 and 29, which makes it possible in the simplest way to use a series of impact devices in a wide range of energies Build individual components.
  • the device can be perfected if the longitudinal slide valve device 2 (FIG. 9) is installed parallel to the pressure line 15 and at least one additional valve 98 is arranged parallel to the same line.
  • the antechamber 99 of this valve 98 is always connected to the pressure chamber 12 of the striking mechanism 1 via the longitudinal slide valve device 2 and is periodically connected to the overflow chamber 13 of the striking mechanism 1 via hydraulic lines 100, 101 and 102.
  • the rear space 103 of this valve 98 is always connected to the pressure chamber 12 via the hydraulic line 17 and is periodically connected to the overflow space 13 of the striking mechanism 1 via the hydraulic line 29.
  • the difference of this embodiment variant from that described above is that the liquid medium reaches its source 6 into the pressure chamber 12 directly, while avoiding the longitudinal slide valve device 2.
  • the longitudinal slide valve device 2 is only intended to periodically connect the antechamber 99 of the additional valve 98 to the pressure or overflow chamber 12 or 13 and thereby to control the position of the closure element 104.
  • the striking device works in this case as follows.
  • the liquid medium flows from its source 6 into the pressure chamber 12 of the striking mechanism 1 and at the same time reaches the antechamber 99 of the additional valve 98 via the hydraulic lines 17, 103, 100.
  • the piston 7 is lifted.
  • the sprung slide element 20 is displaced by a pressure pulse of the liquid medium in the remaining volume of the overflow space 13 in the direction of the first chamber 21 and sets the antechamber 99 of the additional valve 98 over the hydraulic lines 100, 101, 102 through the annular recess 23 with the drain line 25 in connection, by simultaneously separating the antechamber 99 mentioned from the pressure chamber 12 of the striking mechanism 1.
  • the closure element 104 is moved in the direction of the antechamber 99, connecting the pressure and the overflow chamber 12 or 13 via the hydraulic lines 17 and 29.
  • the working stroke of the piston 7 takes place. Otherwise, the function of the striking device is similar to that described above.
  • the arrangement of the longitudinal slide valve device 2 on the line parallel to the pressure line 15 additionally allows the dimensions of this valve device 2 to be reduced and these dimensions not only to be independent of the energy of the single impact of the impacting device according to the invention, but also of the performance of the liquid medium source 6 close.
  • the possibility is achieved to further simplify the additional valve 98 and to increase its reliability, which considerably simplifies the task and expands the possibilities for the construction of the aforementioned type of striking devices.
  • a blind cavity 105 is guided in the housing 3 of the striking mechanism 1 coaxially with its second cavity 5 (FIG. 5) out.
  • This blind annulus 105 is on the side of the first cavity 4 of the striking mechanism 1 via the longitudinal slide valve device 2 with the pressure line 15 and the overflow space 13 of the striking mechanism 1 periodically in communication, while on the side facing the medium to be processed this annulus 105 by means of channels 106 in the housing 3 of the impact mechanism 1 is always connected to the pressure chamber 12.
  • the flow of the liquid medium passes from the source 6 into the pressure chamber 12 via the annular space 105 and the channels 106
  • Piston 7 is the pressure chamber 12 with the overflow chamber 13 via the channels 106, the blind annulus 105, the longitudinal slide valve device 2 and a channel 107 in connection.
  • the device according to the invention operates similarly to that described above.
  • the use of the blind annulus 105 makes it possible to reduce the hydraulic resistances and consequently to increase the efficiency of the striking mechanism 1, to reduce its size, to simplify the construction and to increase the reliability.
  • the striking mechanism 1 is connected to the manipulator 63 of the working machine by means of a bracket 108 rigidly connected to the ring socket 40 and a bolt 109.
  • a hydraulic cylinder of the working machine via a bolt 111 fastened in the console 108 controls the position of the striking mechanism 1 in space.
  • the piston 7 (FIG. 10) is provided on the end 10 side of the piston rod 8 with an exchangeable cylindrical rod (firing pin) 112.
  • This rod 112 with its frustoconical end piece 113 (FIG. 11), which has a spherical end face 114, is inserted into a recess 115 of corresponding geometry in the piston 7.
  • the striking device described above designed according to the invention, allows effective and automatic operation of the medium to be processed by impulses of high energy for the purpose of changing the shape thereof.
  • This device works reliably in the case when different types of deviations from the operating state are observed: "oblique impacts”, “empty impacts”, impacts on media of very low strength to be processed.
  • the simple construction and the low hydraulic resistance of the channels ensure high efficiency, reliability and service life of the device according to the invention.
  • the striking device according to the invention can be operated far from the production base if there is a lack of gas medium.
  • the striking device according to the invention makes it possible to exert a direct influence on the medium to be processed or to use an intermediate body (working tool) for this purpose.
  • the described striking device is intended for the generation of high-energy impact pulses and can be widely used in the mining, destruction and comminution of various rock-like materials in construction, metallurgy and mining.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Disintegrating Or Milling (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Processing Of Solid Wastes (AREA)
  • Junction Field-Effect Transistors (AREA)
  • Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
  • Percussive Tools And Related Accessories (AREA)

Abstract

Dans un dispositif de frappe, le mécanisme de frappe (1) est doté d'un moyen (32) permettant la connexion élastique résiliente avec la machine de travail, et fixé de manière rigide sur une structure (3) dudit mécanisme de frappe (1) dans un plan perpendiculaire à son axe longitudinal, et passant par le centre de la course (0). La première chambre (21) d'un mécanisme (2) de distribution à vanne, est reliée au conduit de décharge (25) par une gorge annulaire (23). Ladite gorge annulaire (23) est réalisée sur la surface intérieure de ladite structure (3) dudit mécanisme de frappe (1), laquelle forme une chambre de trop-plein (13) et est située plus loin le long de l'axe partant de la première chambre (4) qu'un canal (28) ménagé dans ladite structure (3) pour relier ladite chambre de trop-plein (16) à ladite seconde chambre (22) dudit mécanisme (2) de distribution à vanne, dont le canal d'admission (30) contient une vanne (31) de limitation unidirectionnelle. L'instrument de travail (11) lors de courses à vide agit mutuellement avec ladite structure (3) dudit de mécanisme de frappe (1) par l'intermédiaire d'un amortisseur (46) de chocs hydraulique.
EP19900901091 1989-07-11 1989-07-11 Striking device Withdrawn EP0447552A4 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/SU1989/000189 WO1991000952A1 (fr) 1989-07-11 1989-07-11 Dispositif de frappe

Publications (2)

Publication Number Publication Date
EP0447552A1 true EP0447552A1 (fr) 1991-09-25
EP0447552A4 EP0447552A4 (en) 1991-12-18

Family

ID=21617510

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19900901091 Withdrawn EP0447552A4 (en) 1989-07-11 1989-07-11 Striking device

Country Status (3)

Country Link
EP (1) EP0447552A4 (fr)
NO (1) NO912078L (fr)
WO (1) WO1991000952A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1674209A3 (fr) * 2004-12-24 2009-08-12 J.C. Bamford Excavators Limited Outil de percussion à moteur
RU2418949C1 (ru) * 2010-01-11 2011-05-20 Александр Васильевич Мельников Способ наращивания энергии разгона основной механической системы при изменении ее консервативности и механизм для дробления горных пород при его реализации
WO2014116400A1 (fr) 2013-01-28 2014-07-31 Caterpillar Inc. Accumulateur de pression à volume variable

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2330507A1 (fr) * 1975-11-04 1977-06-03 Montabert Roger Machine de percussion
AU536689B2 (en) * 1981-11-24 1984-05-17 John Bennetto Rock breaking apparatus
SU1078051A2 (ru) * 1982-12-24 1984-03-07 Карагандинский Ордена Трудового Красного Знамени Политехнический Институт Гидропневматическое ударное устройство
DE3443542A1 (de) * 1984-11-29 1986-06-05 Fried. Krupp Gmbh, 4300 Essen Hydraulische schlagvorrichtung
DE3504871C2 (de) * 1985-02-13 1994-02-10 Krupp Ag Hoesch Krupp Gerät bestehend aus Trägereinheit und Schlagaggregat
JPH0513509Y2 (fr) * 1986-09-09 1993-04-09

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1674209A3 (fr) * 2004-12-24 2009-08-12 J.C. Bamford Excavators Limited Outil de percussion à moteur
RU2418949C1 (ru) * 2010-01-11 2011-05-20 Александр Васильевич Мельников Способ наращивания энергии разгона основной механической системы при изменении ее консервативности и механизм для дробления горных пород при его реализации
WO2014116400A1 (fr) 2013-01-28 2014-07-31 Caterpillar Inc. Accumulateur de pression à volume variable
EP2948275A4 (fr) * 2013-01-28 2016-08-24 Caterpillar Inc Accumulateur de pression à volume variable

Also Published As

Publication number Publication date
WO1991000952A1 (fr) 1991-01-24
NO912078D0 (no) 1991-05-29
NO912078L (no) 1991-07-23
EP0447552A4 (en) 1991-12-18

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