US1001298A - Pneumatic hammer. - Google Patents

Pneumatic hammer. Download PDF

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US1001298A
US1001298A US59806010A US1910598060A US1001298A US 1001298 A US1001298 A US 1001298A US 59806010 A US59806010 A US 59806010A US 1910598060 A US1910598060 A US 1910598060A US 1001298 A US1001298 A US 1001298A
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valve
port
cylinder
ring
exhaust
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US59806010A
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Reinhold A Norling
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AURORA AUTOMATIC MACHINERY Co
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AURORA AUTOMATIC MACHINERY CO
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L21/00Use of working pistons or pistons-rods as fluid-distributing valves or as valve-supporting elements, e.g. in free-piston machines
    • F01L21/02Piston or piston-rod used as valve members

Definitions

  • This invention relates to a portable pneumatic tool er hammer of that class embracing a barrel or cylinder, a piston or plunger adapted to move therein, and a controlling ⁇ valre through which the air or other tiuid under pressure is admitted to and permitted to escape from the opposite end oi. the barrel or cylinder to give reciprocatory movement to the plunger therein.
  • the invention is illustrated and deseribetl herein as applied to a chipping hammer, otherwise l-:nown as a short strolro hammer, and consists oi' the combination et parts hereinafter described and more particularly pointed out in the appended claims.
  • Fig. 2 is a longitudinal section through the valve which controls the supply and exhaust oit air to and trom the opposite endsl et the cyliinler, the section being in the same plane as that of Fig. l, but the movable member et' the valve being shown in a di'tleront position than that in which it is shown in ittig. l. Fig.
  • FIG. B is a longitudinal sectional -view et.” the central axis of the valve, the plane ot the section being at an angle to that ot the section shown in Figs. l and 2.
  • Fig. 4t is a longitudinal section through the central axis ol the Valve, the plane ot the section being at an angle to that of liig. 3, with the movable member ot the valve in a ditiferent position from that shown in ll ⁇ ig. $3, lti ⁇ ig. 5 is a cross-section through Fig. 4ton the line 5-5 thereo t, the planes ot lthe seetions ot ltigs. 2, and 4t being ⁇ respectively indicated by the lines Q-Q., 3--3 and t--At on said Fig. 5.
  • A represents the barrel or cylinder oit the hammer; B, the piston or plunger adapted to reciprocate therein; (l the tool-carrying nozzle; D the tool, in this case, a chisel; and E the hollow head which is rigidly secured to the rear end o't the cylinder or barrel A and has a rear end wall lill.
  • valve mechanism i'or controlling the admission and exhaust oi air into and trom the cylinder embraces a valve block llX provided with exhaust and admission ports and an annular or cylindric valii'e-ring J surrounding said alive-block, and arranged to slide endwise thereon to open and close said ports, said valvc-ring being provided with oppositely iacing ditlerential pressure areas.
  • tiaid valve-bloel is contined between the rear end ot the barrel and the end wall ll oit the hollow head and, as shown in the drawings, is made in two parts, a body member lvl and a cap member l.
  • valve block Il* is provided with a recess or chamber /t at its torward end, said chamber having a rear end wall 7a2 and an annular wall t, and with a recess or chamber l at its rear end.
  • the valve-ring ⁇ member has a larger pressure area .l1 and a smaller pressure area J which are respectively opposed to annular shoulders H1 and I2 :formed in the outer annular surface of the valve block Il".
  • I( indicates the main exhaust ports adapt ed 'tor the exhaust of air from the inner end ol the cylinder, said exhaust ports extemling through the annular wall 7L of the chan'iber at the forward end of the valve block HX and opening through the outer surtace ol said valve block.
  • lt indicates the main admission ports adapted :tor the supply et air to the inner end of the cylinder, said ports opening ⁇ at their inner ends through the rear end wall 7i? of said chamber t and at their ou ter ends into an annular groove R1 formed in the outer surface of the valve block and located a little forward of the annular shoulder T2 thereof.
  • T4 indicates the main supply ports which extend from the live air chamber I3 at the rear end of the valve block to an annular groove Tf formed in the outer surface of the valve block adjacent to and in front of its shoulder T2 of smaller area. A constant supply of live air is thus provided against the smaller pressure area J 5 of the valve ring.
  • M is a longitudinal exhaust passage in the wall of the cylinder which opens by a port m into the cylinder at its forward end and extends through the valve-block HX to an exhaust port M1 opening through the outer surface of the valve-block at a point near the rear end thereof.
  • the port M constitutes the main exhaust port for the exhaust of air from the forward end of the cylinder.
  • Said exhaust port M1 is covered by the valve ring J when in its rearward position and is uncovered thereby so as to open into the exhaust space X about the valve, when said valve ring is in its forward position.
  • a port P which opens into the passage M and constitutes the supply port adapted for the admission of air into the forward end of the cylinder to drive the piston on its return stroke.
  • T indicate auxiliary, longitudinal exhaust passages located in the wall of the barrel A and opening into the cylinder at their forward ends by ports T2 which are adapted to be uncovered by the forward end of the piston on its return stroke simultaneously with the uncovering of the exhaust port Q3, and opening at their rear ends by ports T1 into the exhaust space X about the controlling valve.
  • N is a longitudinal passage in the cylinder which opens at its forward end by a port Nl into the cylinder at a point in a transverse plane with the port Q2 and adapted to be uncovered simultaneously with said port by the channel or groove B1 in the piston so as to connect the passage il with the passage Q leading to the larger pressure area of the valve ring.
  • the rear end of said longitudinal passage N extends through the valve block HX to a port N2 by means of which it opens into the live air chamber T3 at the rear end of the valve block.
  • the passage lT thus receives a const-ant supply of live air which is adapted to be directed through the port N1, the port Q2, the passage Q and the port Q1, the larger pressure area J1 of the valve ring to shift the same rearwardly against the constant live air pressure on its smaller pressure area J 5 when the piston in its outward stroke, places the ports N1 and Q3 in communication by means of the slot B1 in its outer surface.
  • a channel or groove J X formed in the inner surface of said valve-ring, which channel is adapted to open into t-he supply port P adapted for the supply of air to the forward end of the cylinder when the valve-ring is in its rearward position.
  • Said channel at the same time opens into' a port N3 by means of which thelive air passage N opens through the outer surface of the valve-block HX.
  • the live air passage N is connected by the port N3, the channel J X and the port l) with the longitudinal passage M, so as to supply air t0 the forward end of the cylinder to drive the piston on its return stroke.
  • the passage N thus serves to supply live air not only to the larger pressure area of the valve ring to shift the same rearwardly, but to supply air to the admission port for the forward end of the cylinder when the valve ring has been thus shifted.
  • the operation of the hammer is apparent from the above description.
  • the live air chamber I3 is directly open to the throttle valve chamber as in the hammer described in the application above referred to, so that the opening of the throttle-valve admits a supply of live air through the ports T3 to the smaller pressure area J 5 of the valvering.
  • the port Q is closed by the forward end of the piston and comnninication is opened between the ports N1 and Q2, by the channel or groeve i3' of the piston, thus connectine ⁇ the live air passage N ⁇ with the passage t@ leading te the larger pressure area .ll of the valve-ring. rl'his effects a rearward movement of the vaflvea'ing, against the constant live air pressure on its smaller pressure area J5.
  • said live, air passage having' a port opening through the bearing' surface of said valve-block intermmliate said valvebloclt shoulders, means controlled by the piston for connecting ⁇ said live air passage with the larger pressure area of the valve ring,
  • Valve ring being provided with a as niy invention :LHX my signature in the eirouniferentaiiy extending channel adagted presence of two witnesseses7 this 15th day of to connect said admission port of the eX- December A. D. 1910. hanst passage with said port of the live air REINHOLD A. NORLNG. 4 passage when said Valve ring ⁇ is in its rear Witnesses: position.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Portable Nailing Machines And Staplers (AREA)

Description

R. A. NORLING.
PNEUMATIG HAMMER.
APPLIGATION FILED 11110.19, 1010.
Patented Aug. 22, 1911.
\ w f Twhhbm l@ Inkl w .H u. 1/ Y. ILH` 1 L l l l l l v I I I l I I l l l l nllll lllllll'faL .www 1\|\ Ww/MN .NJW `a @N m im J .......1....H..... -..n----msm,UQHHHHMU mw A. ,I .Q f... `SN f.//\\. EN. U FN.. `PN1 \MNANI..W\NJ Hm. .Nl
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REINI'IOLD A. NORIJING, OF AURORA, ILLINOIS, ASSIGNOR TO AURORA AUTOMATIC lVIACI-IINERY COMPANY, OF AURORA, ILLINOIS, A CORPORATION OF ILLINOIS,
PNEUMATIC HAMMER.
Specification of Letters Patent.
Application filed December 19, 1910. Serial No. 598,060.
To all whom it may concern:
ie .it lznown that I, ltr-narrow A. No1:- Liixo, a citizen ot the United States, and a resident et' Aurora, in the county ot Kane and State oit Illinois, have invented certain new and uset'ul Improvements in Pneumatic llan'nners; and l do hereby declare that the following is a i'ull, clear, and exact description thereof, reference being` had Ato the accompanying drawings, and to the letters ot reference marked thereon, which form a part ot' this specification.
This invention relates to a portable pneumatic tool er hammer of that class embracing a barrel or cylinder, a piston or plunger adapted to move therein, and a controlling` valre through which the air or other tiuid under pressure is admitted to and permitted to escape from the opposite end oi. the barrel or cylinder to give reciprocatory movement to the plunger therein.
The invention is illustrated and deseribetl herein as applied to a chipping hammer, otherwise l-:nown as a short strolro hammer, and consists oi' the combination et parts hereinafter described and more particularly pointed out in the appended claims.
In the drawings :-lt`igure jt re} resents a longitudinal sectional view through the ha1n mer in a plane containing the central axis et the barrel or cylinder. Fig. 2 is a longitudinal section through the valve which controls the supply and exhaust oit air to and trom the opposite endsl et the cyliinler, the section being in the same plane as that of Fig. l, but the movable member et' the valve being shown in a di'tleront position than that in which it is shown in ittig. l. Fig. B is a longitudinal sectional -view et." the central axis of the valve, the plane ot the section being at an angle to that ot the section shown in Figs. l and 2. Fig. 4tis a longitudinal section through the central axis ol the Valve, the plane ot the section being at an angle to that of liig. 3, with the movable member ot the valve in a ditiferent position from that shown in ll` ig. $3, lti`ig. 5 is a cross-section through Fig. 4ton the line 5-5 thereo t, the planes ot lthe seetions ot ltigs. 2, and 4t being` respectively indicated by the lines Q-Q., 3--3 and t--At on said Fig. 5.
The main features of the hammer are Patented Alle'. 22, 1911.
substantially identical with those oi: the hammer shown in an application ior liet* ters Patent oit. the United States, tiled by mo on the '17th day of December, 191i), Serial ANumber 597,865, the particular improvements referred to herein relating to certain novel :features of construction .in the valve block and valve ring.
In the drawings, A represents the barrel or cylinder oit the hammer; B, the piston or plunger adapted to reciprocate therein; (l the tool-carrying nozzle; D the tool, in this case, a chisel; and E the hollow head which is rigidly secured to the rear end o't the cylinder or barrel A and has a rear end wall lill.
The valve mechanism i'or controlling the admission and exhaust oi air into and trom the cylinder embraces a valve block llX provided with exhaust and admission ports and an annular or cylindric valii'e-ring J surrounding said alive-block, and arranged to slide endwise thereon to open and close said ports, said valvc-ring being provided with oppositely iacing ditlerential pressure areas. tiaid valve-bloel is contined between the rear end ot the barrel and the end wall ll oit the hollow head and, as shown in the drawings, is made in two parts, a body member lvl and a cap member l. rlhc valve block Il* is provided with a recess or chamber /t at its torward end, said chamber having a rear end wall 7a2 and an annular wall t, and with a recess or chamber l at its rear end. The valve-ring` member has a larger pressure area .l1 and a smaller pressure area J which are respectively opposed to annular shoulders H1 and I2 :formed in the outer annular surface of the valve block Il".
I( indicates the main exhaust ports adapt ed 'tor the exhaust of air from the inner end ol the cylinder, said exhaust ports extemling through the annular wall 7L of the chan'iber at the forward end of the valve block HX and opening through the outer surtace ol said valve block.
lt indicates the main admission ports adapted :tor the supply et air to the inner end of the cylinder, said ports opening` at their inner ends through the rear end wall 7i? of said chamber t and at their ou ter ends into an annular groove R1 formed in the outer surface of the valve block and located a little forward of the annular shoulder T2 thereof.
T4 indicates the main supply ports which extend from the live air chamber I3 at the rear end of the valve block to an annular groove Tf formed in the outer surface of the valve block adjacent to and in front of its shoulder T2 of smaller area. A constant supply of live air is thus provided against the smaller pressure area J 5 of the valve ring.
M is a longitudinal exhaust passage in the wall of the cylinder which opens by a port m into the cylinder at its forward end and extends through the valve-block HX to an exhaust port M1 opening through the outer surface of the valve-block at a point near the rear end thereof. The port M constitutes the main exhaust port for the exhaust of air from the forward end of the cylinder. Said exhaust port M1 is covered by the valve ring J when in its rearward position and is uncovered thereby so as to open into the exhaust space X about the valve, when said valve ring is in its forward position. At a point forward of the admission slot R1 in the valve block is located a port P which opens into the passage M and constitutes the supply port adapted for the admission of air into the forward end of the cylinder to drive the piston on its return stroke.
Q indicates a longitudinal passage which extends at its rear end into the valve block HX and there opens by a port Ql against the larger pressure area J1 of the valve ring. At its forward end said passage opens by ports Q2 and Q3 into the cylinder, the port Q2 being an admission port which is adapted to be uncovered by an annular groove or channel B1 in the piston on its outward stroke, while the port Q3, which is located forward of the port Q2, is an exhaust port adapted to be covered by the forward end of the piston on the outward stroke but to be uncovered thereby on its return stroke to relieve the pressure on the larger pressure area of the valve-ring J.
T, T indicate auxiliary, longitudinal exhaust passages located in the wall of the barrel A and opening into the cylinder at their forward ends by ports T2 which are adapted to be uncovered by the forward end of the piston on its return stroke simultaneously with the uncovering of the exhaust port Q3, and opening at their rear ends by ports T1 into the exhaust space X about the controlling valve.
N is a longitudinal passage in the cylinder which opens at its forward end by a port Nl into the cylinder at a point in a transverse plane with the port Q2 and adapted to be uncovered simultaneously with said port by the channel or groove B1 in the piston so as to connect the passage il with the passage Q leading to the larger pressure area of the valve ring. The rear end of said longitudinal passage N extends through the valve block HX to a port N2 by means of which it opens into the live air chamber T3 at the rear end of the valve block. The passage lT thus receives a const-ant supply of live air which is adapted to be directed through the port N1, the port Q2, the passage Q and the port Q1, the larger pressure area J1 of the valve ring to shift the same rearwardly against the constant live air pressure on its smaller pressure area J 5 when the piston in its outward stroke, places the ports N1 and Q3 in communication by means of the slot B1 in its outer surface.
Located at the rear of the larger pressure area J l of the valve-ring is a channel or groove J X formed in the inner surface of said valve-ring, which channel is adapted to open into t-he supply port P adapted for the supply of air to the forward end of the cylinder when the valve-ring is in its rearward position. Said channel at the same time opens into' a port N3 by means of which thelive air passage N opens through the outer surface of the valve-block HX. Thus, when the valve-ring is in its rearward position, the live air passage N is connected by the port N3, the channel J X and the port l) with the longitudinal passage M, so as to supply air t0 the forward end of the cylinder to drive the piston on its return stroke. The passage N thus serves to supply live air not only to the larger pressure area of the valve ring to shift the same rearwardly, but to supply air to the admission port for the forward end of the cylinder when the valve ring has been thus shifted.
The operation of the hammer is apparent from the above description. The live air chamber I3 is directly open to the throttle valve chamber as in the hammer described in the application above referred to, so that the opening of the throttle-valve admits a supply of live air through the ports T3 to the smaller pressure area J 5 of the valvering. Starting with the piston B at the rear end of its return-stroke and the valve-ring J at the forward limit of its movement, the main exhaust ports K for the rear end of the cylinder are closed; the exhaust port Ml is open, communication of the exhaust space X with the forward end of the barrel being thus established and the smaller pressure area J 5 of the valve ring is forward of the admission slot R1 in the outer surface of the valveblock ,so that the live air acting against said smaller pressure area has free access to the admission ports R leading to the rear end of the cylinder. A large amount of air is thus admitted to drive the piston on its power stroke. At this time the channel J X of the valve-ring is forward of the plane of the adlmission port P for the admission of air to the forward end of the cylinder. As the valve nears the outer limit of its power stroke, the port Q is closed by the forward end of the piston and comnninication is opened between the ports N1 and Q2, by the channel or groeve i3' of the piston, thus connectine` the live air passage N `with the passage t@ leading te the larger pressure area .ll of the valve-ring. rl'his effects a rearward movement of the vaflvea'ing, against the constant live air pressure on its smaller pressure area J5. By this rearward movement, the main exhaust ports K for Ythe rear end of the cylinder are opened; the smaller pres sure area J5 is shifted to the rear of the admission slot RL, thus cutting oil the supply of live air to the rear end of the cylinder; the exhaust port l) for the :forward end of the cylinder is closed; and the channel JX ef the valve-ring` is brought into the plane of the supply port l) and of the port N3 lead ing,` 'to the live air passage N, thus connecting the forward end of the barrel with the live air supply, so as to drive the piston on its return-stroke. l/Vhen in this rearward movement of the piston the forward end of the piston uncovers the exhaust port Q3 of the passage Q leading to the larger pressure area of the valve-ring, it at the same time opens the exhaust ports ,l2 opening into the exhaust passages rl, thus rel'eving the pressure on said larger pressure area of the valve-ring` and permitting the valve ring te nieve to its forward position under the con stan't live air pressure on its smaller pressure area. The parts are then in the posi tion first described, the piston starts back on its power stroke, and the operation contiir ues as before.
lt will be noted that in this case as in the case of the harnn'ier described in the application referred to above, the admission ports lit for the inner end oil' the cylinder and the supply ports l are inclined outwardly and the slots lll and in the outer annular surface of the valve-block into which they respectively open are closely adjacent. it will also be seen that the longitudinal passages which pass into or through the valve block are drawn inward toward its longitudinal central axis. A short valve block and one of comparatively small diameter is thus made possible, without liiniting the numbe' and cross-sectional area of the ports and passages therein.
l claim as my invention l. rilhe combination with a cylinder and a reciprocating` plunger therein, of a controlling,l valve at the rear of 'the cylinder for mintrollingg' the admission and exhaust of air into and from the cylinder embracing a valve block member and a valve rino,i member, said valve ring member having;` oppositely facing' diillferential pressure areas and being adapted to nieve endwise en said valve block, and said valve block ha vingl annular shoulders, each opposed to one of the pres sure areas of said valve ring, said valve blocl: and cylinder wall beine' provided with a loire'itiulimil exhaust passage adapted for the exhaust of air from the forward end of the cylilnler and with a longitudinal live air pass ire laterally separated therefrom, said exhaust passage having; an exhaust port opening through the bearing surface of said valve-block at a point located near the rear end of said valve bloclt and adapted to be uncovered when said valve ring is in its fois ward position, and an admission port located intermediate the shoulders of said valve block, said live air passage having a port openingn through the bearing: surface of said iailve-bloeli intermediate said valveblocl shoulders, meanscontrolled by the piston for connecting said live air passage with the larger pressure area of the valve ring, and said. valve ring beineI provided with a circumferentially extending,` channel adapted to connect said admission port ef the exhaust passagre with said port of the live air passage when said valve rino; is in its rear position.
2. 'lhe combination with a cylinder and a reciprocalingrl plunger therein, of a controlling valve at the rear of the cylinder for controlling the admission and exhaust of air into and from the cyliinler embracing` a valve block member and a valve ring;l member, said' valve ring;l member having;I opposit'ely facing;` ditl'erential pressure areas and beine' adapted to move end wise on said valve block, and said valve block having;` annular shoulders, each opposed to one of the pressure areas of said valve ring, a plurality of supply ports opening?) through the bearing surface of said valve block at points forward of said valve-bloeitr shoulder of smaller area, a plurality of admission ports for the rear end of the cylinder opening through the bearing surface of said valve bleek at points spaced longitudinally forward of said supply ports, said valve block and cylinder wall being;` provided with a long {itlulinal ex haust passage adapted for the exhaust of air from the forward end of the cylinder and with a longitudinal live air passage laterally separated therejli'rom, said exhaust passage ha vini;l an exhaust port opening' through the bearing' surface of said valve-block at a point located near the rear end of said valve block and adapted te he uncovered when said valve ringr is in its forward position, and an admissien port for the forward end of the cylinder located. at a point spaced longitudinally forward of the admission ports for the rear end of the cylinder, said live, air passage having' a port opening through the bearing' surface of said valve-block intermmliate said valvebloclt shoulders, means controlled by the piston for connecting` said live air passage with the larger pressure area of the valve ring,
and said Valve ring being provided with a as niy invention :LHX my signature in the eirouniferentaiiy extending channel adagted presence of two Witnesses7 this 15th day of to connect said admission port of the eX- December A. D. 1910. hanst passage with said port of the live air REINHOLD A. NORLNG. 4 passage when said Valve ring` is in its rear Witnesses: position. CHARLES BROS,
in testimonya that ela-iin the foregoing CHAs. H. G'REENY.
Copies of this patent may be obtained for ive cents each, by addressing the Commissioner of lEatents. Washington, D. C.
US59806010A 1910-12-19 1910-12-19 Pneumatic hammer. Expired - Lifetime US1001298A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2641510A (en) * 1947-06-02 1953-06-09 Case Co J I Wheel suspension

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2641510A (en) * 1947-06-02 1953-06-09 Case Co J I Wheel suspension

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