WO1982002468A1 - Appareillage de rupture de materiaux - Google Patents

Appareillage de rupture de materiaux Download PDF

Info

Publication number
WO1982002468A1
WO1982002468A1 PCT/US1981/000117 US8100117W WO8202468A1 WO 1982002468 A1 WO1982002468 A1 WO 1982002468A1 US 8100117 W US8100117 W US 8100117W WO 8202468 A1 WO8202468 A1 WO 8202468A1
Authority
WO
WIPO (PCT)
Prior art keywords
seal
shank
housing
impact
sealing surface
Prior art date
Application number
PCT/US1981/000117
Other languages
English (en)
Inventor
Tractor Co Caterpillar
Original Assignee
Fox Lawrence E
Reinsma Harold L
Woody Albert L
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 Fox Lawrence E, Reinsma Harold L, Woody Albert L filed Critical Fox Lawrence E
Priority to JP50201681A priority Critical patent/JPS57502209A/ja
Priority to PCT/US1981/000117 priority patent/WO1982002468A1/fr
Priority to AU72910/81A priority patent/AU7291081A/en
Priority to CA000387968A priority patent/CA1140167A/fr
Priority to EP19810305806 priority patent/EP0057791A1/fr
Publication of WO1982002468A1 publication Critical patent/WO1982002468A1/fr

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21C—MINING OR QUARRYING
    • E21C27/00—Machines which completely free the mineral from the seam
    • E21C27/20—Mineral freed by means not involving slitting
    • E21C27/28—Mineral freed by means not involving slitting by percussive drills with breaking-down means, e.g. wedge-shaped tools
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F5/00—Dredgers or soil-shifting machines for special purposes
    • E02F5/30—Auxiliary apparatus, e.g. for thawing, cracking, blowing-up, or other preparatory treatment of the soil
    • E02F5/32—Rippers
    • E02F5/323—Percussion-type rippers
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
    • E21D9/10—Making by using boring or cutting machines
    • E21D9/106—Making by using boring or cutting machines with percussive tools, e.g. pick-hammers

Definitions

  • This invention relates generally to impact apparatus for fracturing material and, more particularly, to a relatively reciprocatable shank/housing configuration which facilitates sealing therebetween.
  • Numerous apparatus are available for fracturing rock formations and other materials in mining, excavation, and earthmoving in general.
  • Fracturing materials by blasting with explosives can be an efficient technique, but may, under some circumstances, present an unacceptably high risk when used near population centers.
  • Mechanical impact apparatus such as jack hammers and/or crank driven impactors are known but are relatively slow and inefficient or constitute bulky devices which are not easily manipulated into limited access places.
  • U.S. Patent 3,868,145 which issued
  • each of the devices includes a fracturing shank which is reciprocatably mounted adjacent a power supply housing.
  • the shank during operation, reciprocates between a first impact receiving position and a second, material fracturing position where the fracturing shank is in penetrating contact with the fracturable material.
  • U.S. Patent 3,868,145 the fracturing shank has an impact receiving portion which protrudes into the housing and is intermittently impacted by a rotatable eccentric to provide such reciprocating motion.
  • an intermediate hammer member extends into the energy supply housing and is used to transfer energy generated and stored within that housing to an impact receiving portion of the shank which is external to the housing.
  • Such intermediate hammer member extends into and is, likewise, reciprocably mounted relative to the housing.
  • a material fracturing impact apparatus which has a fracturing shank which is arcuately, reciprocatably mounted about a pivot axis and which has a cylindrically shaped sealing surface which is arranged about a longitudinal sealing surface axis which is perpendicular to a radial line extending from the pivot axis to the sealing surface's longitudinal axis.
  • An annular seal which is connected to both the shank's sealing surface and a housing into which the shank is arcuately reciprocatable has a flexible portion which is bounded by an inner margin that lies along the radial line. When in an unstrained configuration, the annular seal is symmetrically disposed about a longitudinal seal axis extending therethrough.
  • the seal assumes such unstrained configuration only when the shank's sealing surface occupies a position along the arcuate reciprocation path in which the longitudinal sealing surface axis coincides with the longitudinal seal axis.
  • Non-symmetric disposition of the seal due to radial deflection thereof relative to the longitudinal seal axis necessarily obtains for all other shank positions along such arcuate reciprocation path as a result of securing the seal to both the housing and the sealing surface which is arcuately reciprocatable relative to the housing.
  • Such radial deflection of the seal during the shank's arcuate reciprocation is minimized by arranging the longitudinal sealing surface axis perpendicular to the pivot axis' radial line and arranging the seal's flexible portion's inner nargin along such radial line. Minimization of the seal's radial deflection contributes to a longer seal life, provides greater fracturing apparatus reliability, and improves the productivity thereof.
  • Fig. 1 is a partial transverse sectional view of a material fracturing apparatus in which the invention is incorporated;
  • Fig. 2 is an enlarged view of a portion of
  • Fig. 3a is a front elevational view of a portion of a seal used in the apparatus illustrated in
  • Fig. 1 and 2; Fig. 3b is a transverse sectional view of the seal illustrated in Fig. 3a;
  • Fig. 4 is a front elevational view of a seal retaining ring used to secure the seal to a housing illustrated in Fig. 1 and 2; and Fig. 5 is a rear elevational view of a portion of a shank illustrated in Fig. 1 and 2.
  • FIG. 1 illustrates an impact fracturing apparatus 10 having an arcuately reciprocatable shank member 12, a housing 14 having an interior 15 into which the shank 12 is arcuately reciprocatable, and an annular seal member 16 connected to the reciprocatable shank 12 and the housing 14 and having a longitudinal seal axis 16a.
  • the shank 12 is reciprocatable between a first, extreme impact receiving position (illustrated in full) and a second, extreme material fracturing position (illustrated in phantom) .
  • Arcuate reciprocation of the shank 12 to the right (as viewed in Fig. 1) beyond its first, extreme impact receiving position is precluded by a stopping member 18 which abuts the shank 12 when it reaches its first extreme position.
  • a stopping member 20 which is disposed on the opposite side of the shank 12 and is preferably attached to a stationary casing member 21 (attachment not shown) , abuts the shank 12 when it reaches the second, extreme material fracturing position.
  • a pin 22 pivotally joins the shank 12 to the casing member 21 which also supports the housing 14 to constrain the reciprocation of the shank 12 along an arcuate path about a pivot axis 24.
  • the shank 12 includes a sealing portion 26, an impact receiving portion 28, and a fracturing tip 29.
  • the shank's sealing portion 26 has a cylindrical sealing surface 26a and a longitudinal axis 26b about which the cylindrical sealing surface 26a is disposed.
  • the impact receiving portion 28 has a longitudinal axis 28b and an impact receiving surface 28a which is engageable at intermittent times with a rotatable eccentric impacting member 30.
  • a shank guide structure 31 includes two shank guides 32 (the one nearer the viewer having been removed to provide better visibility of the impact receiving portion 28) which are fixedly attached to the housing interior 15 and together transversely define an opening within which the impact receiving portion 28 is receivable.
  • the shank guides 32 are arranged in closely spaced, transverse relation with the impact receiving portion 28 so as to direct the impact receiving surface 28a into an optimum impact receiving relationship with the impact member 30 and to resist transversely directed forces exerted on the shank 12 by the impacting member 30 and by the fracturable material.
  • the shank guides 32 have an axial length 32a which is greater than the distance separating the extreme reciprocation positions of the shank's impact receiving surface 28a as illustrated in Fig. 1.
  • the mechanism for intermittently engaging the impacting member 30 with the impact receiving surface 28a is better described in U.S. Patent 3,868,145 which issued February 15, 1975, and is assigned to the present invention's assignee.
  • the sealing surface's longitudinal axis 26b is perpendicular to a line 33 which extends radially from the pivot axis 24. As a result, the longitudinal axis 26b remains perpendicular to the.radial line 33 for all positions assumable by the shank 12 along its arcuate reciprocation path.
  • the sealing surface's longitudinal axis 26b is inclined relative to the impact receiving portion's longitudinal axis 28b by an angle of approximately 10° by example.
  • the annular elastomeric seal 16 (best illustrated in Fig. 3A and 3B) has a relatively rigid inner terminating portion 36 and a relatively rigid outer terminating portion 38 which are respectively fixedly attached to the sealing surface 26a and the housing 14 so as to prevent debris intrusion into the housing's interior 15 and to prevent lubricant leakage out of the housing's interior 15.
  • the seal apparatus 16 is unstrained symmetrically disposed about the longitudinal seal axis 16a and the sealing surface's longitudinal axis 26b coincides with the seal's longitudinal axis 16a.
  • the seal 16 includes an annular flexible portion 40 which is disposed between and joined to the relatively rigid terminating portions 36 and 38.
  • the convolutions 42 and- 44 have a convoluted centersurface 16b which appears as a centerline in Fig. 3B. It is to be understood that the centersurface 16b is the locus of points traced by the centerline illustrated in Fig. 3 as it is rotated about the longitudinal axis 16a. It is to be further understood that the centersurface 16b is an imaginary surface which is introduced for reference purposes only.
  • the convolutions 42 and 44 respectively include an inner and an outer margin 46 and 4S which bound the flexible portion 40, interface with the inner and outer terminating portions 36 and 38 respectively, and have exemplary thicknesses perpendicular to the centersurface 16b of 4 mm and 3 mm, respectively.
  • the inner margin 46 constitutes the effective inner edge of the flexible portion 40 and is disposed along the radial line 33.
  • the inner convolution 42 has a smaller radius of curvature R, of 17.77 mm by example as measured from an axis of curvature 0, to the centersurface 16b than does the outer convolution 44 whose radius of curvature R 2 of 23.69 mm by example is measured from an axis of curvature 0- to the centersurface 16b.
  • the axes of curvature 0, and 0 anxiety are separated, or offset, by a distance which is designated generally by the reference letter 0 and, by example, equals 16.0 mm.
  • seal 16 corresponds to a seal which utilizes an elastomer material commonly known in the trade as Hytrel.
  • a suitable alternative seal material constitutes fabric reinforced neoprene rubber which varies in exemplary thickness from 7 mm at the inner margin 46 to 5 mm at the outer margin 48.
  • the offset 0 of the radii of curvature by example equals 10.0 mm while the radii of curvature for the inner and outer convolutions 42 and 44, respectively, constitute 16.78 mm and 22.37 mm for such fabric reinforced neoprene seal material.
  • the inner and outer margins 46 and 48 respectively interface with and are connected to the inner and outer terminating portions 36 and 38.
  • the thickness of seal 16 perpendicular to the centersurface 16b varies from the inner margin 46 to its outer margin 48 with decreases from the inner margin's thickness being proportional to the radial distance H (illustrated in Fig. 3B) separating the centersurface 16b at.the inner margin 46 from the centersurface 16b at the seal location in question.
  • the seal's terminating portions 36 and 38 have thicker cross sections (as measured perpendicularly to the centersurface) than the flexible portion 40 since the terminating portions 36 and 38 are actually joined to the relatively reciprocatable shank 12 and housing 14.
  • the flexible seal portion 40 has isolation faces 50 and 52 which are equidistant from the convoluted centersurface 16b and are respectively exposed to the environment surrounding the impact apparatus 10 and that existing in the housing's interior 15.
  • the seal 16 further includes an annular connection member 54 of U-shaped cross section v/hich is disposed about and vulcanized bonded to the inner terminating portion 36.
  • the U-shaped connection member 54 is open along the axial end adjacent the inner margin 46 and is closed on the opposite axial end.
  • the connection member 54 has a radially inv/ardly facing surface 56 which is threadably engageable with the sealing surface 26a.
  • a plurality (two in the illustrated case) of openings 57 in the connecting member 54 are provided to receive a tightening tool used to relatively rotate and threadably engage the seal 16 and the sealing surface 26a with a predetermined torque.
  • a cylindrical locking extension 58 protrudes from the connection member 54 and is deformable into a plurality of restraining slots 59
  • a retainer ring 60 illustrated in Figs. 1, 2, and 4 is engagable with the seal's outer terminating portion 38 and is securable to the housing 14 by a plurality of threaded screw bolts 62.
  • the retaining ring 60 is annular relative to the longitudinal seal axis 16a except in the vicinity of a vertical centerline therethrough where the retaining ring's radial thickness is reduced to permit disposition thereof betv/een the seal's outer terminating portion 38 and the casing member 21.
  • the retaining ring 60 and the outer terminating portion 38 are engageable along cooperatively ramped interfacing surfaces 38a and 60a which are respectively disposed thereon. Tightening the screw bolts 62 displaces the retaining ring 60 relative to the outer terminating portion 38, increases the interference therebetween as a result of the cooperative inclination of the ramped surfaces 38a and 60a, compresses the seal's outer terminating portion 38. Optimum sealing of the seal's outer terminating portion 38 with the housing 14 and the retaining ring 60 obtains when the retaining ring 60 engages the housing 14.
  • a securing bead 38b of the terminating portion 38 extends radially inwardly and is receivable in a circular notch 14a formed in the housing 14.
  • FIG. 5 An enlarged view of the impact receiving portion 28 is illustrated in Fig. 5 as viewed from a vantage point A as indicated in Fig. 1.
  • the impact receiving portion 28 has an outer periphery 28c which constitutes a four-sided figure whose corners have been rounded.
  • the longest protrusion of the outer periphery 28c from the impact receiving portion's longitudinal axis 28b is the radius 28d which is smaller than the . radius separating the sealing surface 26a from the sealing longitudinal axis 26b.
  • Such size differential enables axial displacement of the seal 16 over the impact receiving portion's outer periphery 28c.
  • this oscillation produces an arcuate motion which may be resolved into two perpendicular components of displacement: an axial displacement component parallel to the longitudinal axis 16a of the unstrained seal 16 and a radial displacement component perpendicular to the unstrained seal axis 16a.
  • axial displacement parallel to the longitudinal axis 16a of the unstrained seal 16
  • radial displacement perpendicular to the unstrained seal axis 16a.
  • Seal strain produced by the combined axial and radial displacements is greater than that produced by the axial displacement alone, primarily because the radial displacement deforms the seal into an unsymmetrical configuration relative to the longitudinal axis 16a of the unstrained seal. It was found that the additional strain resulting from such radial deflection of the seal 16 could be minimized by: (1) canting the seal 16 and the sealing portion 26 to provide perpendicularly between the radial line 33 and the longitudinal axis 25b; and (2) arranging the seal's inner margin 46 (located where the seal 16 becomes rigid or is effectively attached to the shank 12) along the radial line 33. Cooperatively canting the longitudinal axes 26b and 16a to provide coincidence thereof when the shank configuration of Fig.
  • seal 16 which are responsible for providing such substantially equalized maximum strains are the tapered thickness which is a function of the radial distance H, the convolutions' different radii of curvature R, and 2 and the offset distance 0 between the axes of curvature.
  • the seal 16 may be removed from the material fracturing impact apparatus 10 by extracting the screw bolts 62, removing the retaining ring 60, disengaging the deformed areas of the locking extension 58 from the locking slots 59, and rotating the seal 16 and integral connection member 54 to threadably disengage them from the sealing surface 26a.
  • the shank 12 After moving the stopping member 20 to an unobstructing position, the shank 12 is arcuately displaced to a convenient position where the impact receiving portion 28 is disengaged from the shank guides 32 and is resident outside the housing's interior 15.
  • the seal 16 is then axially displaced along the outer periphery 28c of the impact receiving member 28 until it passes the impact receiving surface 28a and can be removed to a remote location.
  • the stopping member 20 is moved to an unobstructing position; the shank 12 is arcuately displaced to a position where the impact receiving portion 28 is exterior to the housing 14; the seal 16 is slidingly displaced over the impact receiving portion's outer periphery 28c; the seal 16 and integral connection member 54 are rotated relative to the threaded sealing surface 26a until they are threadably engaged to a suitable tightness; areas of the locking extension 58 which are aligned v/ith the restraining slots 59 are deformed thereinto; the terminating portion 38 of seal 16 is engaged with the housing 14 such that the restraining bead 38b is inserted in the notch 14a to secure the seal 16 in place and facilitate assembly of the retaining ring 60; the retaining ring 60 is disposed on the opposite side of the seal's terminating portion 38 from the housing 14; and the screw bolts 62 are inserted through the retaining ring 60 and torqued into the housing 14 to provide the desired
  • the cross section of the flexible seal portion 40 flexes betv/een an "S-shape" and a nearly straight line as illustrated in Fig. 1.
  • the respective orientation of the convolusions 42 and 44 toward and away from the housing 14 cause fracturable material and other debris exposed to the isolation face 50 to be expelled therefrom during seal flexure and thus avoid potentially debilitating, seal immobilizing debris accumulation on the isolation face 50.
  • connection member 54 shields the vulcanized bond from direct impingemen-t by fracturable material during shank reciprocation and maximizes the bonding area between the seal material (preferably Hytrel) and the connection member 54 (preferably carbon steel) for the purpose of reducing the stress (and thus increasing the life) imposed thereon during shank reciprocation.
  • seal material preferably Hytrel
  • connection member 54 preferably carbon steel

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Mechanical Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Sealing Devices (AREA)
  • Confectionery (AREA)
  • Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)
  • Heating, Cooling, Or Curing Plastics Or The Like In General (AREA)

Abstract

Un marteau piqueur (10) pour effectuer la rupture de materiaux comprend un boitier (14) et une tige (12) qui est montee de facon adjacente au boitier (14) de facon a etre animee d'un mouvement de va-et-vient autour d'un axe de pivotement (24). La tige (12) comporte une partie (28) recevant l'impact et une partie formant joint (26). La partie formant joint (26) presente une surface d'etancheite cylindrique (26a) qui est disposee autour d'un axe longitudinal (26b). Un tel axe longitudinal (28b) est perpendiculaire a une ligne radiale (33) qui s'etend depuis l'axe de pivotement (24) et est incline selon un angle predetermine par rapport a un axe longitudinal (28b) qui traverse la partie (28) recevant l'impact. Un joint annulaire (16) est relie a la surface d'etancheite (26a) et au boitier (14) afin d'empecher le passage de materiaux dans et hors du boitier (14). Le joint (16) presente une partie flexible (40) dont le bord interne (46) s'etend le long de la ligne radiale (33).
PCT/US1981/000117 1981-01-26 1981-01-26 Appareillage de rupture de materiaux WO1982002468A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
JP50201681A JPS57502209A (fr) 1981-01-26 1981-01-26
PCT/US1981/000117 WO1982002468A1 (fr) 1981-01-26 1981-01-26 Appareillage de rupture de materiaux
AU72910/81A AU7291081A (en) 1981-01-26 1981-01-26 Material fracturing apparatus
CA000387968A CA1140167A (fr) 1981-01-26 1981-10-15 Concasseur
EP19810305806 EP0057791A1 (fr) 1981-01-26 1981-12-09 Concasseur

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
WOUS81/00117810126 1981-01-26
PCT/US1981/000117 WO1982002468A1 (fr) 1981-01-26 1981-01-26 Appareillage de rupture de materiaux

Publications (1)

Publication Number Publication Date
WO1982002468A1 true WO1982002468A1 (fr) 1982-08-05

Family

ID=22161066

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1981/000117 WO1982002468A1 (fr) 1981-01-26 1981-01-26 Appareillage de rupture de materiaux

Country Status (5)

Country Link
EP (1) EP0057791A1 (fr)
JP (1) JPS57502209A (fr)
AU (1) AU7291081A (fr)
CA (1) CA1140167A (fr)
WO (1) WO1982002468A1 (fr)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1493768A (en) * 1920-08-28 1924-05-13 Rice Portable Rock Drill Corp Dustguard for percussion machines
US2305265A (en) * 1942-05-01 1942-12-15 Letourneau Inc Sealing boot assembly
US2748750A (en) * 1953-01-13 1956-06-05 Armour Res Found Vibrationless pneumatic impact tool
US3381987A (en) * 1965-06-04 1968-05-07 Ford Motor Co Double wall seal for articulated joints
US3611816A (en) * 1969-06-02 1971-10-12 Continental Gummi Werke Ag Sleeve for sealing coaxially arranged parts
US3770322A (en) * 1971-04-12 1973-11-06 Caterpillar Tractor Co Apparatus for fracture of material in situ with stored inertial energy
US3788628A (en) * 1972-11-10 1974-01-29 Wright Barry Corp Pneumatic isolator
US3868145A (en) * 1973-08-23 1975-02-25 Caterpillar Tractor Co Eccentric ring impacting mechanism for in-situ rock breakers
US3998466A (en) * 1973-08-31 1976-12-21 Aisin Seiki Kabushiki Kaisha Flexible sealing boot

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1980001188A1 (fr) * 1978-12-11 1980-06-12 R Livesay Mecanisme d'impact actionne mecaniquement

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1493768A (en) * 1920-08-28 1924-05-13 Rice Portable Rock Drill Corp Dustguard for percussion machines
US2305265A (en) * 1942-05-01 1942-12-15 Letourneau Inc Sealing boot assembly
US2748750A (en) * 1953-01-13 1956-06-05 Armour Res Found Vibrationless pneumatic impact tool
US3381987A (en) * 1965-06-04 1968-05-07 Ford Motor Co Double wall seal for articulated joints
US3611816A (en) * 1969-06-02 1971-10-12 Continental Gummi Werke Ag Sleeve for sealing coaxially arranged parts
US3770322A (en) * 1971-04-12 1973-11-06 Caterpillar Tractor Co Apparatus for fracture of material in situ with stored inertial energy
US3788628A (en) * 1972-11-10 1974-01-29 Wright Barry Corp Pneumatic isolator
US3868145A (en) * 1973-08-23 1975-02-25 Caterpillar Tractor Co Eccentric ring impacting mechanism for in-situ rock breakers
US3998466A (en) * 1973-08-31 1976-12-21 Aisin Seiki Kabushiki Kaisha Flexible sealing boot

Also Published As

Publication number Publication date
CA1140167A (fr) 1983-01-25
EP0057791A1 (fr) 1982-08-18
AU7291081A (en) 1982-08-16
JPS57502209A (fr) 1982-12-16

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