Classifications

• • 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
• • 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
• • 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
• • 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
  • B25D9/16—Valve arrangements therefor
  • B25D9/18—Valve arrangements therefor involving a piston-type slide valve
• • 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
  • B25D9/26—Control devices for adjusting the stroke of the piston or the force or frequency of impact thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25D—PERCUSSIVE TOOLS
  • B25D2217/00—Details of, or accessories for, portable power-driven percussive tools
  • B25D2217/0011—Details of anvils, guide-sleeves or pistons
  • B25D2217/0023—Pistons
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25D—PERCUSSIVE TOOLS
  • B25D2250/00—General details of portable percussive tools; Components used in portable percussive tools
  • B25D2250/221—Sensors
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/8593—Systems
  • Y10T137/86493—Multi-way valve unit

Definitions

• Percussion apparatus driven by an incompressible fluid under pressure.
• the present invention relates to a percussion apparatus driven by an incompressible fluid under pressure.
• Percussion devices driven by an incompressible fluid under pressure are supplied with fluid, so that the resultant hydraulic forces successively applied to the striking piston, moves it alternately in one direction and then in the other.
• the piston moves alternately inside a bore or cylinder in which are arranged at least two opposing chambers of different sections.
• One, constantly supplied with pressurized fluid, called the lower chamber ensures the rise of the piston and another antagonist of larger section, called upper chamber, is alternately fed with pressurized fluid during the accelerated stroke of the piston for striking and connected to the return circuit of the device during the ascent of the piston.
• the devices are also provided with a chamber, called a braking chamber, which serves to hydraulically stop the piston stroke when the tool is not resting on the material to be destroyed. There is never any metal shock between the striking piston and the cylinder.
• This braking chamber can be advantageously formed in the extension of the annular recovery chamber.
• the energy per stroke is the kinetic energy given to the piston, which depends on the stroke stroke and the supply pressure.
• Patent EP 0 214 064 describes an apparatus which makes it possible to obtain an automatic adaptation of the percussion parameters, thanks to the presence in the cylinder of the apparatus of a channel supplied with fluid according to the position of the piston after the impact and the eventual rebound of the latter on the tool.
• Patent EP 0 256 955 describes an apparatus which makes it possible to obtain the same result, as a function of the pressure variations in the upper chamber or the lower chamber, following the effect of rebound of the piston on the tool, thanks to the presence of the hydraulic element sensitive to these variations.
• EP 0 715 932 describes a simplified system that can equip small and medium power devices. This system consists, during the rebound phase of the piston after the impact, to determine the possible existence of an instantaneous flow of fluid flowing from the upper chamber to the feed circuit and to use this signal to control the percussion parameters such as typing pressure or frequency of the device.
• the object of the invention is to provide a percussion apparatus driven by an incompressible fluid under pressure which is simple, reliable and inexpensive, while allowing protection of the apparatus against the vacuum strikes.
• the invention relates to a percussion apparatus driven by an incompressible fluid under pressure, comprising:
• a control device for varying the stroke of the striking piston between a long stroke and a short stroke and vice versa the control device being connected on the one hand to the distributor and on the other hand to at least one channel opening into the cylinder of the striking piston and capable of being placed in communication with the lower chamber during the movement of movement of the striking piston upwards,
• control device comprises a cylinder , in which at least one channel also opens into the cylinder of the striking piston and a channel connected to the distributor, and in which is mounted a slide having a first face is located in a first chamber permanently subjected to a predetermined pressure and the second face is located in a second chamber connected to the braking chamber.
• the apparatus according to the invention is simpler, more reliable and less expensive.
• the first face of the spool of the control device is subjected to the action of a spring while the second face is subjected to the pressure prevailing in the braking chamber, the latter being in communication with an adjacent annular chamber formed in the cylinder, as the piston has not exceeded its theoretical strike position, the annular chamber being connected to the high pressure.
• a calibrated orifice constituted by a nozzle, is arranged on the channel connecting the braking chamber and the second chamber of the control device.
• a non-return valve is arranged on the channel connecting the braking chamber and the second chamber of the control device, and this second chamber is connected by a channel comprising a calibrated orifice constituted by a nozzle, the channel connecting the control device to the distributor.
• the first chamber of the control device is permanently connected to a high pressure circuit by a channel comprising a calibrated orifice constituted by a nozzle.
• the first chamber of the control device is permanently connected to the high pressure circuit by a channel opening into the lower chamber of the cylinder of the striking piston.
• the first chamber of the control device is permanently connected to the high pressure circuit by a channel connected to the high pressure fluid supply source.
• the cylinder of the control device comprises several successive different sections
• the drawer comprises several successive different sections
• the drawer and the cylinder defining an annular chamber permanently connected to the distributor, the drawer being arranged to allow, during its displacement under the effect of fluid from the braking chamber, the communication of the annular chamber with the other channel (s) opening into the cylinder of the striking piston.
• the slide of the control device comprises a central bore in which is slidably mounted a piston comprising two successive sections of different diameters, a large diameter on the side of the first chamber and a small diameter on the side of the second chamber, an annular chamber being formed in the central zone of the slide, between the latter and the central piston, this annular chamber being permanently connected to the annular chamber of the slide connected to the distributor, the latter also being connected to the second chamber by a channel having a calibrated orifice, and the small section end of the piston being disposed facing the channel connecting the second chamber to the braking chamber.
• the slide of the control device comprises a central bore in which is slidably mounted a piston comprising two successive sections of different diameters, a large diameter on the side of the first chamber and a small diameter on the side of the second chamber, an annular chamber being formed in the central region of the drawer, between the latter and the central piston, this annular chamber being permanently connected to an annular chamber of the connected drawer; constant to the low pressure circuit, the latter also being connected to the second chamber by a channel having a calibrated orifice, and the small section end of the piston being disposed facing the channel connecting the second chamber to the braking chamber.
• the slide of the control device comprises a central bore in which is slidably mounted a piston comprising two successive sections of different diameters, a large diameter on the side of the first chamber and a small diameter on the side.
• the second chamber, an annular chamber (60) being formed in the central zone of the slide, between the latter and the central piston, this annular chamber being permanently connected to an annular chamber of the slide connected constantly to the low pressure circuit, the second chamber being connected to the first chamber by a channel having a calibrated orifice, and the small section end of the piston being disposed facing the channel connecting the second chamber to the braking chamber.
• Figure 1 shows a longitudinal sectional view of a first device.
• Figures 2, 3 and 4 show longitudinal sectional views of this apparatus in other operating positions.
• Figure 5 shows a longitudinal sectional view of a variant of the same device.
• Figures 6, 7 and 8 show longitudinal sectional views of the apparatus of Figure 5 in other operating positions.
• Figure 9 shows a longitudinal sectional view of another variant of the same apparatus.
• Figures 10, 11 and 12 show longitudinal sectional views of the apparatus of Figure 9 in other operating positions.
• Figure 13 shows longitudinal sectional views of a variant of the stroke control valve described in Figures 1 to 4 in three different operating phases.
• Figures 14 to 16 show longitudinal sectional views of other variants of the same apparatus.
• Figures 17 and 18 show longitudinal sectional views of two variants of the regulation slide described in Figures 5 to 8.
• the apparatus shown in FIGS. 1 to 4 is a percussion device driven by an incompressible fluid under pressure, between a long stroke and a short stroke and vice versa.
• the percussion apparatus comprises a stage piston 1 alternately movable inside a bore or stage cylinder formed in the body 2 of the apparatus, and coming to strike each cycle a tool 3 slidably mounted in a bore in the body 2 coaxially with the cylinder.
• the piston 1 defines with the cylinder 2 a lower annular chamber 4 and a higher chamber 5 of larger section formed above the piston.
• a main distributor 6 mounted in the body 2 makes it possible to put the upper chamber 5, alternatively in connection with a supply of high pressure fluid 7 during the accelerated descent stroke of the piston for striking, as shown in FIG. 2, or with a low pressure circuit 8 during the ascent of the piston, as shown in FIG.
• the annular chamber 4 is permanently supplied with fluid under high pressure through the channel 9, so that each position of the spool of the distributor 6 causes the strike stroke of the piston 1, then the return stroke.
• the piston 1 also forms with the body 2, an annular chamber 10, called the braking chamber, formed in the extension of the lower chamber 4 and supplied with fluid under high pressure by the latter.
• the braking chamber allows, by the principle of "DASH POT", to dissipate the striking energy of the piston 1 when the tool 3 is not close to its theoretical position of operation, ie in support on the conical part 11 of the body 2.
• the choice of small or large stroke is established from a steering device.
• the control device comprises a slide 12 mounted in a cylinder formed in the body 2 and into which, axially offset, two channels 13 and 14 open out into the cylinder of the piston 1.
• the channel 13 is connected to a control section of the piston. main distributor 6 through an annular groove 15 and a channel 16.
• the channel 14 opens into the cylinder containing the piston 1 and serves as control channel of the main distributor 6 in case of short stroke.
• the control device may connect the channels 13 and 14 or keep them isolated from one another.
• the drawer 12 defines with the body 2 three separate chambers.
• a chamber 17 constantly connected to the fluid under high pressure through the channel 18 containing a calibrated orifice 19, the annular chamber 4 and the channel 9.
• An annular chamber 20 subjected to the piloting pressure of the channel 13 and finally a chamber 21 opposed to the chamber 17 and connected to the braking chamber 10 by a channel 22.
• the pilot pressure transmitted by the channel 16 to the main distributor 6 is equal to the supply pressure during the accelerated descent of the striking piston 1 and equal to the return pressure during the ascent of the same piston.
• the pressure changes are effected thanks to the edges of the striking piston 1, these pressures are maintained during the movement of the piston by calibrated orifices (not shown) being an integral part of the main distributor 6.
• the tool 3 When the apparatus works in homogeneous hard ground, the tool 3 remains close to its support 11 under the effect of the thrust exerted by the carrier on the device. At each impact, the edge 23 of the piston 1 does not cross the edge 24 of the lower chamber 4.
• the pressures established in the annular chambers 4 and 10 are identical and equal to the supply pressure.
• the pressure that is established in the chamber 20 is therefore either equivalent to or less than that established in the chambers 17 and 21.
• the drawer 12 is in compression or pushed down and thus takes a position which isolates the circuits 13 and 14. Only the long stroke controlled directly by the channel 16 is possible.
• Figure 1 shows the apparatus when the piston 1 has made an impact and begins its climb stroke.
• FIG. Figure 2 shows the apparatus when the piston 1 has completed its rise and begins its descent stroke.
• the channel 16 is connected to the high pressure circuit 7 via the channel 9 and the lower chamber 4, which causes a displacement of the distributor valve 6 in the position shown in Figure 2.
• the upper chamber 5 is connected to the high pressure circuit 7.
• the resultant hydraulic forces on the plunger piston moves it in the direction of typing.
• the channel 16 is connected to the low pressure circuit 8 via the channel 25 and the groove 15, which causes a displacement of the distributor valve 6 in the The position shown in Figure 3. It follows that the upper chamber 5 is connected to the low pressure circuit 8 and thus the striking piston initiates its accelerated recovery.
• the orifice 19 positioned on the circuit 18 has the function of limiting the speed of movement of the slide 12, thus avoiding any end-of-stroke shocks.
• FIGS. 5 to 8 show a variant of the apparatus which has a different stroke selection drawer.
• FIGS. 5 and 6 respectively represent the apparatus when the tool 3 is close to its zone its striking with the piston 1 initiating its ascent and the piston initiating its accelerated descent.
• FIGS. 7 and 8 respectively represent the apparatus when the tool 3 is moved away from its theoretical striking zone with the beginning of raising of the piston 1 and the beginning of the descent of the piston 1.
• the drawer 30 delimits with the body 2 four chambers. Two opposite chambers 31 and 32 and of identical section, the chamber 32 being constantly connected to the supply circuit by the channel 18 and the chamber 31 constantly connected to the braking chamber 10 by the channel 22. Finally the drawer 30 delimits with the body 2 two annular chambers of identical sections 33 and 34 opposite.
• the chamber 33 is constantly connected to the low pressure circuit 8 of the apparatus.
• the chamber 34 is connected to the control circuit of the main distributor 6 by the channels 13 and 16. As previously, the drawer 30 will be displaced by the pressure created in the chamber 10 when the piston 1 extends its striking stroke in soft ground, determining thus running in short race.
• the return to the low position of the spool 30 will be done at each cycle when the chamber 34 is supplied with pressurized fluid by the control circuit 16, 13.
• the chambers 31 and 32 subjected to the same pressure and of sections Similarly, the respective pressures of the annular chambers 33 and 34 allow the unbalance of the slide 30 downwards according to the schematic representation.
• Figures 9 to 12 show a variant of the apparatus with a piston assembly 1 and body 2 which define three separate chambers including the annular braking chamber 10 constantly connected to the return circuit 8.
• Figures 9 to 12 respectively representing the beginnings of upward and downward acceleration of the piston 1 in cases of uniform homogeneous hard or heterogeneous terrains.
• the travel selector drawer 37 delimits, with the body 2, four distinct chambers, of which two opposite chambers 38 and 39 and of equivalent sections, the chamber 38 being always connected to the return circuit 8, and the chamber 39 being connected to the braking chamber 10 by the channel 22.
• the other two annular chambers 40 and 41 are as previously, respectively connected to the return circuit and the control circuit.
• the pressurization of the control circuit at each cycle ensures the reinitialization of the system.
• FIG. 13 shows three operating phases of a variant of the stroke control slide 12 described with reference to FIGS. 1 to 4.
• the slide valve 42 always determines three chambers 17, 20 and 21 with the bore in which it is mounted, as was the case for the drawer 12.
• the slide 42 comprises a central bore in which is slidably mounted a piston 43 having two successive sections of different diameters, a large diameter on the side of the chamber 17 and a small diameter on the side of the 21.
• An annular chamber 44 is formed in the central zone of the slide, between the latter and the piston 43, this annular chamber being permanently connected to the annular chamber 20 via an orifice 45.
• annular 20 is also connected to the chamber 21 by a channel 46 having a calibrated orifice 47, and the small section end of the piston is disposed facing the channel 22 connecting the chamber 21 to the braking chamber 10.
• the piston 43 acts as a non-return valve which allows the injection of pressurized fluid between the channel 22 and the chamber 21 and constrains, when it bears against the body 2, the fluid contained in the chamber 21 at s escape through the channel 46 and the orifice 47 to the annular chamber 20.
• This provides a system independent of any negative pressure waves transmitted by the channel 22 during repeated impacts on the tool 3.
• the annular sections of the slide 42 and the piston 43 are dimensioned so that they move in the same pressure conditions as the slide 12 described with reference to Figures 1 to 4.
• FIG. 14 shows the operation of another variant of the stroke control slide 12 described with reference to FIGS. 1 to 4.
• the slide 48 comprises a first face subjected to the action of a spring 49 and a second face subjected to the pressure prevailing in the braking chamber 10.
• a calibrated orifice 50 constituted by a nozzle, is disposed on the channel 22 connecting the braking chamber and the slide 48. The speed of the slide 48 is limited in both direction through the calibrated orifice 50, and the return of the drawer to its original position is provided by the spring 49.
• FIG. 15 represents a variant of the apparatus of FIG. 14 in which the spring 49 has been replaced by a hydraulic return powered by a channel 51 having a calibrated orifice 52 which limits the speed of movement of the slide 48.
• Figures 17 and 18 show two variants of the regulating slide 30 described with reference to Figures 5 to 8.
• the drawers 57 and 58 always determine four chambers 31, 32, 33 and 34 with the bores in which they are mounted, as was the case for the drawer 30.
• the drawer 57 comprises a central bore in which is slidably mounted a piston 59 comprising two successive sections of different diameters, a large diameter on the side of the chamber 32 and a small diameter on the side of the chamber 31.
• An annular chamber 60 is formed in the central zone of the slide, between the latter and the piston 59, this annular chamber being permanently connected to the annular chamber 33 via an orifice 61.
• the annular chamber 33 is also connected to the chamber 31 by a channel 62 having a calibrated orifice 63, and the small section end of the piston is disposed facing the channel 22 connecting the chamber 31 to the chamber e braking 10.
• the drawer 58 differs from the drawer 57 essentially in that the chamber 31 is not connected to the chamber 33 by the channel 62 but is connected to the chamber 32 by a channel 64 having a calibrated orifice 65.
• the piston 59 acts as a check valve which allows the injection of fluid under pressure.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Mechanical Engineering (AREA)
• Automation & Control Theory (AREA)
• Percussive Tools And Related Accessories (AREA)
• Fluid-Pressure Circuits (AREA)
• Reciprocating Pumps (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=37775489

Family Applications (1)

Country Status (12)

Cited By (1)

Families Citing this family (11)

Family Cites Families (18)

• 2006
  • 2006-06-27 FR FR0605764A patent/FR2902684B1/fr active Active
• 2007
  • 2007-06-27 WO PCT/FR2007/001082 patent/WO2008000958A2/fr active Application Filing
  • 2007-06-27 BR BRPI0714073-8A patent/BRPI0714073A2/pt not_active Application Discontinuation
  • 2007-06-27 ES ES07803791T patent/ES2424361T3/es active Active
  • 2007-06-27 AU AU2007264799A patent/AU2007264799A1/en not_active Abandoned
  • 2007-06-27 CA CA 2654547 patent/CA2654547A1/fr not_active Abandoned
  • 2007-06-27 US US12/227,768 patent/US8151900B2/en active Active
  • 2007-06-27 EP EP20070803791 patent/EP2032316B1/de active Active
  • 2007-06-27 CN CN2007800241542A patent/CN101500761B/zh active Active
  • 2007-06-27 KR KR1020087030354A patent/KR101383219B1/ko active IP Right Grant
• 2008
  • 2008-10-30 IL IL195012A patent/IL195012A0/en unknown
• 2009
  • 2009-01-26 NO NO20090380A patent/NO20090380L/no unknown

Non-Patent Citations (1)

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