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US1222663A - Multiple-plunger impact-hammer. - Google Patents

Multiple-plunger impact-hammer. Download PDF

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Publication number
US1222663A
US1222663A US13531016A US13531016A US1222663A US 1222663 A US1222663 A US 1222663A US 13531016 A US13531016 A US 13531016A US 13531016 A US13531016 A US 13531016A US 1222663 A US1222663 A US 1222663A
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United States
Prior art keywords
hammers
bores
housing
tool holder
tool
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Expired - Lifetime
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US13531016A
Inventor
Harold D Penney
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HENRY B NEWHALL
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Individual
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Priority to US13531016A priority Critical patent/US1222663A/en
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Publication of US1222663A publication Critical patent/US1222663A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25DPERCUSSIVE TOOLS
    • B25D11/00Portable percussive tools with electromotor or other motor drive
    • B25D11/06Means for driving the impulse member
    • B25D11/10Means for driving the impulse member comprising a cam mechanism
    • B25D11/102Means for driving the impulse member comprising a cam mechanism the rotating axis of the cam member being coaxial with the axis of the tool

Definitions

  • This invention relates to percussion instruments in general, and more particularly to drills in which the tool is actuated to strike the work with a number of blows followingone another in rapid succession.
  • One of the main objects of the present in- 5 vention is to provide a percussion instrument by which a number of blows following one another in rapid succession may be produced with great facility, and the wear be distributed to a number of the parts of the instrument.
  • a percussion instrument having a plurality of hammers for engaging the tool of theinstrument and means for actuating such plurality of ham-
  • Still another object of the present invention is to provide in a percussioninstrument the arrangement in which a plurality of so hammers may engage a single tool and such from the subjoined detail description of one specific embodiment thereof illustrated in the accompanying drawings, in which Figure 1 is a plan view partly broken away.
  • Fig. 2 is a section along the line 22 of Fig. 1. c
  • Fig. 3 is an enlarged section along the line 33 of Fig. 2.
  • Fig. 4 is an enlarged fragmental section alongthe line 4-4 of Fig. 1.
  • Fig. 5 is a diagrammatic view showing the positions of the hammers relative to one another at an instant during a cycle of operation.
  • a main housing member H having a lower cylindrical portion 2 and an upper portion 3 flaring outwardly.
  • the bore of the lower cylindrical portion is of suliicient 66 diameter to slidingly accommodate the head 4 of the tool holder 5 which has a stem 6 of less diameter than the head and slidable in the bushing 7 which is screw threadedly connected to the inside of the portion 2.
  • the head 4: of the toolholder 5 is normally spaced from the bushing 7 by means of the spring 8.
  • the stem 6 of the tool holder 5 is provided with a tapered opening to receive the tool, such as the drill 9.
  • the upper face of the head 4 is preferably rounded to present a proper working face to the active ends 11 of any number of hammers 10.
  • hammers are provided which are disposed in the bores 12 of the flaring portion 3.
  • the bores 12, as illustrated, converge as they approach the cylindrical portion 2 so that the hammers 10 will travel in a path of movement that is in clined to the path of movement of the tool holder 5.
  • the housing H Centrally of the bores 12 the housing H is provided with a bore 13 which terminates at its lower end in the bearing recess 14 and intermediate of its length com-. municates with each of the bores 12, the bore 13 diminishing in diameter as it approache the cylindrical portion 2.
  • each hammer comprises essentially a lower active end 10, a cam groove 15, and a spring guiding stud 16 at its upper end.
  • the cam member 17 which has a stud 18 at its lower end to seat in the recess 14:, and a tapering body portion 19 rotatably mounted in the lower tapering portion of the bore 13around which body is formed the spiral cam ledge 20, which starts at the enlarged end of the body portion 19 and terminates at the diminished portion of the body portion 19, the terminating ends being so disposed relative to one another that when a hammer, as shown in Fig.
  • the cam member 17 is guided not only by the stud 18 but also by the cam ledge 20 which conforms to the bore 13.
  • the springs 26, which are disposed in the bores 12, are strained between the ends of the hammers 11 surrounding the stud 16 and the abutments secured to the upper ends of the bores 12.
  • the abutments for the springs 26 of two of the bores 12 disposed diametrically opposite to one another consist of plain screw caps 27, as shown in Fig. 1, while the abutments for the other bores 12 consist of the lower ends of the posts 28, to the outer free ends of which the fixed handle 29 is secured.
  • the upper edges of the hammers 11 at the upper ends of the grooves will, of course, be the active faces of the hammers when cooperating with the ledge 20, and thus are therefore rounded to facilitate such cooperation.
  • any greater or less number than four hammers may be provided in accordance with the general arrangement herein disclosed, and that these hammers, if only one cam ledge is provided, will succeed one another during a single revolution of the cam member 17.
  • the timing of the cam ledge relative to the hammers 11 is such, as illustrated in Fig. 5, that the hammer 11 last released will be drawn upward out of the path of movement of the succeeding hammer before such succeeding hammer is released.
  • a percussion instrument the combination with a housing, of a tool holder having a conical impact top-face, slidably mounted in said housing, a plurality of reciprocating hammers (with their respective axes located at the outer ends upon a circle, and at their inner impacting ends located in like manner upon a circle of less diameter than the outer, both circles having the axis of the tool-holder as a common center) adapted to actuate said tool-holder, and means for actuating said hammers.
  • a percussion instrument the coinbination with a housing, of a tool-holder slidably mounted in said housing, a plurality of reciprocating hammers (with their respective axes located at the outer ends upon a circle, and at their inner impacting ends located in like manner upon a circle of less diameter than the outer, both circles having the axis of the tool-holder as a common center) adapted to actuate said tool-holder, means for normally maintaining said hammers under tension in a direction toward said tool holder, and means for successively releasing said hammers to strike said tool holder and again retracting such hammers.
  • a percussion instrument the combination with a housing, of a tool holder slidably mounted in said housing, there be ing a plurality of bores in said housing converging as they approach the tool holder, hammers slidably mounted in said bores, means for successively retracting said hammers out of tool holder engaging position, and means for maintaining said hammers under tension against'said retracting means.
  • a percussion instrument the combination with a housing, of a tool holder having a conical impact top-face slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, a plurality of reciprocating hammers adapted to actuate said tool-holder, slidably mounted in said bores (with their respective axes located at the outer ends upon a circle, and at their innerimpacting ends located in like manner upon a circle of less diameter than the outer, both circles having the axis of the toolholder as a common center) means for successively retracting said hammers out of tool-holder engaging position, means for maintaining said hammers under tension against said retracting means, and means for maintaining the tool holder under tension and in the path of movement of the hammers.
  • a percussion instrument the combination with a housing, of a tool-holder having a conical impact top face, slidably mounted in said housing, a plurality of reciprocating hammers impacting with the conical impact top face of the tool-holder, having their respective axes located at the outer ends upon a circle, and their inner impacting ends located iii like manner upon a circle of less diameter than the outer, both circles having the axis of the tool-holder as a common center; means for normally maintaining said hammers under tension in a direction toward said tool-holder, means for successively retracting and releasing said hammers to strike the conical impact face of said tool holder and again retracting such hammers, and means for maintaining the tool-holder under tension in the path of movement of the hammers when released.
  • a percussion instrument the combination with a housing, ofa tool holderslidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, ham- 1 mers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, means for normally maintaining said hammers under tension in a direction toward said tool holder, there being a bore direction toward said tool holder, there being a bore centrally disposed of said con-.
  • cam ledge on said cam member there being cam'grooves in said hammers to receive said cam ledge and coeperate. therewith to retract said hammers after having struck said tool holder, and means for rotating said cam member.
  • a percussioninstrument the combination with a housing, of a tool holder slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, hammers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, means for normally maintaining said hammers under tension in a direction toward said tool holder, there being a bore centrally disposed of said converging bores,
  • a cam member rotatably mounted in said centrally disposed bore, a cam ledge on said cam member, there being cam grooves in said hammers toreceive said cam ledge and ooeperate therewith to retract said hammers after having struck'said tool holder, a bevel gear at the upper edge of said cam member, a shaft extending through said housing, a second bevel gear at the end of Copies of this patent may be obtained for said shaft in mesh with said first mentioned bevel gear, and a handle on said shaft wherea by said shaft may be actuated.
  • a percussion instrument thecombination with a housing, of a tool holder slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, hammers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, abutments at the diverging ends of said hammer bores, springs disposed between said abutments and said hammers to maintain said hammers under tension in .a direction toward said toolholder, there being a bore centrally disposed of said converging bores, and a cam member rotatably mounted in said centrally disposed bore and coeperating with the hammers to retract said hammers after having struck said tool holder.
  • a percussion instrument the combination with a housing, of a tool holder slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder,
  • hammers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, abutments at the diverging ends of said hammer bores, springs disposed between said abutments and said hammers to maintain said hammers under tension in a direction toward saidtool holder, there being a borecentrally disposed of said converging bores, a cam member rotatably mounted in said centrally disposed bore and cotiperating with the hammers to retract said hammers after having struck said tool holder, extensions on two of said abutments, and a handle secured to such extensions.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Percussive Tools And Related Accessories (AREA)
  • Drilling And Boring (AREA)

Description

H. D. PENNEY. I MULTIPLE PLUNGER IMPACT HAMMER.
APPLICATION FILED DEC-6.19m-
' Patented Apr. 17,1917.
2 SHEETS-SHEET .16 '/2.f 16 I I 0, III I 21 a 5 24 M'lzesses; W 6 a J fiaml (122720 7- lyfiz'slzg, I Q
run 90.. nmm unm. wAsnmcmN. u. c.
H. D. PENNEY.
MULTIPLE PLUNGER IMPACT HAMMER.
cmou FILED 050.6, m
Patented Apr. 17, 1917. 2 shins-5min '2.
In ventor:
Iii
Witnesses! UNITED STATES PATENT OFFICE.
HAROLD D. PENNEY, OF PELHAMQIIEW YORK, ASSIGNOR T HENRY 13.
LITTLETON, NEW HAMPSHIRE.
NEWHALL, OF
MULTIPLE-PLUNGER IMPACT-HAMMER.
Specification of Letters Patent.
Patented Apr. 17, 1917.
Application filed December 6, 1916. Serial 110. 135,310.
.Plunger Impact-Hammers, of which the following is a specification.
This invention relates to percussion instruments in general, and more particularly to drills in which the tool is actuated to strike the work with a number of blows followingone another in rapid succession.
One of the main objects of the present in- 5 vention is to provide a percussion instrument by which a number of blows following one another in rapid succession may be produced with great facility, and the wear be distributed to a number of the parts of the instrument.
To this endone of the main objects of the present invention is to provide a percussion instrument having a plurality of hammers for engaging the tool of theinstrument and means for actuating such plurality of ham- Still another object of the present invention is to provide in a percussioninstrument the arrangement in which a plurality of so hammers may engage a single tool and such from the subjoined detail description of one specific embodiment thereof illustrated in the accompanying drawings, in which Figure 1 is a plan view partly broken away.
Fig. 2 is a section along the line 22 of Fig. 1. c
Fig. 3 is an enlarged section along the line 33 of Fig. 2.
Fig. 4 is an enlarged fragmental section alongthe line 4-4 of Fig. 1.
Fig. 5 is a diagrammatic view showing the positions of the hammers relative to one another at an instant during a cycle of operation.
In the embodiment illustrated, there is shown a main housing member H having a lower cylindrical portion 2 and an upper portion 3 flaring outwardly. The bore of the lower cylindrical portion is of suliicient 66 diameter to slidingly accommodate the head 4 of the tool holder 5 which has a stem 6 of less diameter than the head and slidable in the bushing 7 which is screw threadedly connected to the inside of the portion 2. The head 4: of the toolholder 5 is normally spaced from the bushing 7 by means of the spring 8. The stem 6 of the tool holder 5 is provided with a tapered opening to receive the tool, such as the drill 9. The upper face of the head 4 is preferably rounded to present a proper working face to the active ends 11 of any number of hammers 10.
In the present instance, four hammers are provided which are disposed in the bores 12 of the flaring portion 3. The bores 12, as illustrated, converge as they approach the cylindrical portion 2 so that the hammers 10 will travel in a path of movement that is in clined to the path of movement of the tool holder 5. Centrally of the bores 12 the housing H is provided with a bore 13 which terminates at its lower end in the bearing recess 14 and intermediate of its length com-. municates with each of the bores 12, the bore 13 diminishing in diameter as it approache the cylindrical portion 2. I
In the bores 12, the hammers 11 are slidably disposed. Each hammer comprises essentially a lower active end 10, a cam groove 15, and a spring guiding stud 16 at its upper end.- In the lower end of the bore 13 there is disposed the cam member 17 which has a stud 18 at its lower end to seat in the recess 14:, and a tapering body portion 19 rotatably mounted in the lower tapering portion of the bore 13around which body is formed the spiral cam ledge 20, which starts at the enlarged end of the body portion 19 and terminates at the diminished portion of the body portion 19, the terminating ends being so disposed relative to one another that when a hammer, as shown in Fig. 5,-is raised to the highest portion of the ledge 20 and drops therefrom, it will, after dropping, be received on the ledge 20 adjacent to the lowest end. To the enlarged endof the body portion 19, there is secured a bevel gear 21 which is in mesh with the bevel gear 22 secured to the shaft 23 extending through the extension 24 and body portion 3. The outer end of the shaft 23 may be connected to any suitable source of power. In thepresent instance, to the outer end of the shaft 23 there is secured a handle 25.
The cam member 17 is guided not only by the stud 18 but also by the cam ledge 20 which conforms to the bore 13.
For normally maintaining the hammers depressed against the cam ledge 20 and in turn for actuating them in a downward direction, the springs 26, which are disposed in the bores 12, are strained between the ends of the hammers 11 surrounding the stud 16 and the abutments secured to the upper ends of the bores 12. The abutments for the springs 26 of two of the bores 12 disposed diametrically opposite to one another consist of plain screw caps 27, as shown in Fig. 1, while the abutments for the other bores 12 consist of the lower ends of the posts 28, to the outer free ends of which the fixed handle 29 is secured.
The upper edges of the hammers 11 at the upper ends of the grooves will, of course, be the active faces of the hammers when cooperating with the ledge 20, and thus are therefore rounded to facilitate such cooperation.
From the foregoing it will be seen that any greater or less number than four hammers may be provided in accordance with the general arrangement herein disclosed, and that these hammers, if only one cam ledge is provided, will succeed one another during a single revolution of the cam member 17. The timing of the cam ledge relative to the hammers 11 is such, as illustrated in Fig. 5, that the hammer 11 last released will be drawn upward out of the path of movement of the succeeding hammer before such succeeding hammer is released.
It is obvious that various changes and modifications may be made to the details of construction without departing from the general spirit of the invention.
I claim:
1. In a percussion instrument, the combination with a housing, of a tool holder having a conical impact top-face, slidably mounted in said housing, a plurality of reciprocating hammers (with their respective axes located at the outer ends upon a circle, and at their inner impacting ends located in like manner upon a circle of less diameter than the outer, both circles having the axis of the tool-holder as a common center) adapted to actuate said tool-holder, and means for actuating said hammers.
2. In a percussion instrument, the coinbination with a housing, of a tool-holder slidably mounted in said housing, a plurality of reciprocating hammers (with their respective axes located at the outer ends upon a circle, and at their inner impacting ends located in like manner upon a circle of less diameter than the outer, both circles having the axis of the tool-holder as a common center) adapted to actuate said tool-holder, means for normally maintaining said hammers under tension in a direction toward said tool holder, and means for successively releasing said hammers to strike said tool holder and again retracting such hammers.
3. In a percussion instrument, the combination with a housing, of a tool holder slidably mounted in said housing, there be ing a plurality of bores in said housing converging as they approach the tool holder, hammers slidably mounted in said bores, means for successively retracting said hammers out of tool holder engaging position, and means for maintaining said hammers under tension against'said retracting means.
4:. In a percussion instrument, the combination with a housing, of a tool holder having a conical impact top-face slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, a plurality of reciprocating hammers adapted to actuate said tool-holder, slidably mounted in said bores (with their respective axes located at the outer ends upon a circle, and at their innerimpacting ends located in like manner upon a circle of less diameter than the outer, both circles having the axis of the toolholder as a common center) means for successively retracting said hammers out of tool-holder engaging position, means for maintaining said hammers under tension against said retracting means, and means for maintaining the tool holder under tension and in the path of movement of the hammers.
5. In a percussion instrument the combination with a housing, of a tool-holder having a conical impact top face, slidably mounted in said housing, a plurality of reciprocating hammers impacting with the conical impact top face of the tool-holder, having their respective axes located at the outer ends upon a circle, and their inner impacting ends located iii like manner upon a circle of less diameter than the outer, both circles having the axis of the tool-holder as a common center; means for normally maintaining said hammers under tension in a direction toward said tool-holder, means for successively retracting and releasing said hammers to strike the conical impact face of said tool holder and again retracting such hammers, and means for maintaining the tool-holder under tension in the path of movement of the hammers when released.
6. In a percussion instrument, the combination with a housing, ofa tool holderslidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, ham- 1 mers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, means for normally maintaining said hammers under tension in a direction toward said tool holder, there being a bore direction toward said tool holder, there being a bore centrally disposed of said con-.
verging bores, a cam member rotatably mounted in said centrally disposedbore, a
cam ledge on said cam member, there being cam'grooves in said hammers to receive said cam ledge and coeperate. therewith to retract said hammers after having struck said tool holder, and means for rotating said cam member.
8. In a percussioninstrument, the combination with a housing, of a tool holder slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, hammers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, means for normally maintaining said hammers under tension in a direction toward said tool holder, there being a bore centrally disposed of said converging bores,
a cam member rotatably mounted in said centrally disposed bore, a cam ledge on said cam member, there being cam grooves in said hammers toreceive said cam ledge and ooeperate therewith to retract said hammers after having struck'said tool holder, a bevel gear at the upper edge of said cam member, a shaft extending through said housing, a second bevel gear at the end of Copies of this patent may be obtained for said shaft in mesh with said first mentioned bevel gear, and a handle on said shaft wherea by said shaft may be actuated.
9. In a percussion instrument, thecombination with a housing, of a tool holder slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder, hammers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, abutments at the diverging ends of said hammer bores, springs disposed between said abutments and said hammers to maintain said hammers under tension in .a direction toward said toolholder, there being a bore centrally disposed of said converging bores, and a cam member rotatably mounted in said centrally disposed bore and coeperating with the hammers to retract said hammers after having struck said tool holder.
10. In a percussion instrument, the combination with a housing, of a tool holder slidably mounted in said housing, there being a plurality of bores in said housing converging as they approach the tool holder,
hammers slidably mounted in said bores and adapted to engage the tool holder to actuate the same, abutments at the diverging ends of said hammer bores, springs disposed between said abutments and said hammers to maintain said hammers under tension in a direction toward saidtool holder, there being a borecentrally disposed of said converging bores, a cam member rotatably mounted in said centrally disposed bore and cotiperating with the hammers to retract said hammers after having struck said tool holder, extensions on two of said abutments, and a handle secured to such extensions.
HAROLD D. PENNEY. Witnesses: I
FRED. J. DOLE, GUsTAv DREWS.
five cents each, by addressing the Commissioner of Patents Washington, D. 0.
US13531016A 1916-12-06 1916-12-06 Multiple-plunger impact-hammer. Expired - Lifetime US1222663A (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2451063A (en) * 1944-06-02 1948-10-12 Brown Morris Riveting tool
US3251629A (en) * 1962-12-31 1966-05-17 William B Terry Material stripping machine
US3952813A (en) * 1975-02-07 1976-04-27 Nikolai Prokhorovich Chepurnoi Percussive device for driving holes in soil
US20070000674A1 (en) * 2005-02-10 2007-01-04 Stefan Sell Hammer
US20070012466A1 (en) * 2005-02-10 2007-01-18 Stefan Sell Hammer
US20080000663A1 (en) * 2005-02-10 2008-01-03 Stefan Sell Hammer
US20160138238A1 (en) * 2013-06-07 2016-05-19 Progressive Ip Limited Improvements in & relating to pile and post driving equipment
US20180036842A1 (en) * 2015-02-26 2018-02-08 Ecoroll Ag Werkzeugtechnik Hammering device for influencing workpieces and associated method

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2451063A (en) * 1944-06-02 1948-10-12 Brown Morris Riveting tool
US3251629A (en) * 1962-12-31 1966-05-17 William B Terry Material stripping machine
US3952813A (en) * 1975-02-07 1976-04-27 Nikolai Prokhorovich Chepurnoi Percussive device for driving holes in soil
US20070000674A1 (en) * 2005-02-10 2007-01-04 Stefan Sell Hammer
US20070012466A1 (en) * 2005-02-10 2007-01-18 Stefan Sell Hammer
US20080000663A1 (en) * 2005-02-10 2008-01-03 Stefan Sell Hammer
US20160138238A1 (en) * 2013-06-07 2016-05-19 Progressive Ip Limited Improvements in & relating to pile and post driving equipment
US20180036842A1 (en) * 2015-02-26 2018-02-08 Ecoroll Ag Werkzeugtechnik Hammering device for influencing workpieces and associated method
US10549392B2 (en) * 2015-02-26 2020-02-04 ECOROLL AG Werkzengtechnik Hammering device for influencing workpieces

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