US1554128A

US1554128A - Pneumatic hammer

Info

Publication number: US1554128A
Application number: US707239A
Authority: US
Inventors: Joseph A C Robertson
Original assignee: Individual
Current assignee: Individual
Priority date: 1924-04-17
Filing date: 1924-04-17
Publication date: 1925-09-15
Anticipated expiration: 1942-09-15

Description

Scpt. l5, 1925.

1,54,128 J. A. c. ROBERTSON NEUMATIG HAMMER Filed April 17. 1924 l Patented Sept. l5, 1925.

UNITED STATES PATENT ersten.

Josera A. c. ROBERTSON', or ronoNfro, onreine.

canapa.

rNnUMarIc Y nannten.`

Appiication medapru 17, 1924. seriaiiwo. 707,239.

To all whom t may concern.'

Be it known that I, Josnrir A. C. Bonner soN, of the city ot Toronto, in the county of York, Province of Ontario, Canada, a subject of the King of Great Britain, have invented certain new and useful Improve- `ments in Pneumatic Hammers, of which the following is a specification.' y

This invention relates to pneumatic hammers adapted to automatically feed a nail into position under the hammer and to drive it home, and my object is to provide-aide- Avice of this character whichis of' simplecf Fig. 4;;

Fig. 6 a diagrammatic view showing the construction employed to cause the hammer to be reciprocated;

V the plunger tube; and

Fig.. 7 a crosssection of the nail feeding device;

Fig. 8 a Fig. 9 a plan view of Fig. 10 a plan Lview ott horizontal section ot the same;

the hopper;

the underside of Fig. 11 a plan view of the underside of the base. Y

ln the drawings like numerals of reerence indicate corresponding parts in the diderent figures.

l is a cylinder having exhaust and inlet ports 2 and 3, the latter communicates with a valve controlled iiuid supply pipe 4 carried by the cyinder head 5 connected to the cylinder. A handle 6 is also formed on or connected with the head. In the cylinder is slidabiy and rotatably mounted a ham-r mer or piston 7 having a pair of inlet passages 8 and 8 and a pair ci" exhaust passages 9 and 9a formed therein. The inlet passage 8 is adapted to lregister with the inlet port 3 to direct the 'duid to the top of the cylinder and at thev same time the exhaust passa-ge 9 is adapted to register with the exhaust port 2 to exhaust the air below l the cylinder and thus cause the piston to `be moved downwardly in the cylindersee Figs. 1 and 4. `The otherset of passa es 8and 9 are adapted to register with t e inlet and outlet. ports and' 2 to cause the piston to be moved upwardly 1n the cylinder and there- Vfore the passage 8'* communicates'- with the space below the iston and the passage 9* communicates wit the space above the piston, vseeFig. 3.

To cause these two

sets ovf'passages

8 and 9, 8a and 9,l to alternately register with the inletV and exhaust ports respectively, and thus automatically causethe piston to be reciprocated, 'the iston at theend of each stroke is partial y rotated' alternatelyy in opposite directions in the following Inanner.

Stationary members

10 and 11 are suit# ably secured at opposite ends of `the cylinder, the member 1() being located at one side of the cylinder and having its lower face` inclined in one direction. `The member'll is located at the opposite side of the 'cylinder and has its upper face inclined in the opposite direction to `the inclined face of the `member 10, These members are tted in recesses formed in the wall of the cylin der and project into the bore thereof.' The piston is provided with

inclined shoulders

12 and 13 adapted toengage the inclined faces of the members 10 and l1 respectively.y These shoulders are formed by forming re` cesses 12a and 13 in the periphery of the piston, the shoulder 12 being inclined in the v. same direction as the inclined ace of the member 10 and is also of greater width than the latter. With this arrangement as the piston -moves upwardly, with the passages 8 and 9 in register with the ports 3 and 2 respectively, see Fig. 3, the shoulder 12 engages the member 10 and rides up the inclined face of the latter which causes the piston` to be rotated suiiiciently to cut o the said communications and bring the passages 8 and 9 into register with the ports 3 and 2 retpectively. The fluid is then directedlto the space above the piston which forces the latter downwardly land causes the shoulder 13 to engage the inclined face of the member 11. This 'shoulder is inclined in the same direction `as the inclined face of the last mentioned member and is of greater width than the latter whereby the piston is partially rotated in the opposite direction to that caused by the engagement of the shoulder 12 and the memberlO. The communications between the passages 8 and 9 and the ports 3 and 2 are thus out off and whichthenailis to be driven.

the passages 8 and 9 are registered with the said ports respectively and thepiston is moved upwardly in the cylinder as here inbefore described. It will readily be seen that with the above construction the pistontuate a nail set4 `orlplunger '14, which isv axially movable v,in a""tube 15, removably carried by the lcylinder 1. 'The tube is slidably mounted on Ia-tilbular base 16 Aadapted to rest on ,or against the object, through y On the base is suitably carried a feed chamber 17 which communicates-with the bore thereof and carries a magazine comprising a hopper 18 and intermediate magazine sections '17* The sections and the hopper have a telescopic connection with one'another and with the feedV chamber so that they may be easily and quickly separated from one another or from the `feed chamber.` The 'magazine sections are of curved tubular shape so that by re- I kmoving one or both of them the hopper may i be positioned relative to the feed chamber rvsofthat the nails in the hopper will feed y gravity intothe feed chamber when the device is used in a horizontal aosition. The

' lower end of the hop r is re uced in width so that only one nail at a time can dro into the magazine sections 17'* and the fee chamber 17.

Referring to Figs.- 1, 3 and 5, it will he noted that the plunger 14 is provided with an integral collar -19 adapted to enga e an annular shoulder 20 formed in the tu e 15 which limits the downward movement of the lungerv to prevent it falling through the evice when the latter is lifted off the part being nailed. To limit the upward movement` of theQplunger relative to the tube, the collar 1'9 is adapted to engage a bushing 21- carried inthe bottom portion of the cylinderL. The upper end ofthe plunger passes through this bushing, which is removable, so that it may be easily replaced when worn, as it i's important that no fluid leakage should occur at this point. The lower end of the plunger is slidably mounted in the bore ofthe base 16 whereby the plunger, thetube 15, and the cylinder 1 maybe moved axially of the base to cause a. nail to be driven home or to permit these parts to be positioned so that a nail may be fed into the bore of the base as hereinafter described.

The lower end of the tube 15 is slotted at'22 to provide clearance for the feed chamber 17 see Fig. 10. To position this slot. relative to the feed chamber and to limit the upward movement of the tube l5 relative to the base 16,v a in andl slot connection 23 is provided in t ese parts. To limit the downd ward movement of the ytube 15 relative to the base, the latter is provided with a shoulder 16* adapted to engage the bottom of the said tube.. ,l

Toautomatically feed a nail into the bore of the base 16, when the plunger 14'is raised, I provide a pair of feeders 24 formed of disks having eripheral teeth cut therein (see Figs. 7 and) 8) and adapted to be actuated as follows. The feeders operate through slots formed in the chamber 17 and are secured, with their teeth in vertical alinement, to opposite ends of a tube 25 journalled on an actuating rod 26 which is 'ournalled in a pair of brackets 27 secure to the feed chamber 17. A disk 28 secured to the actuating rod has a. dog 29 pivotally connected thereto which is adapted to ick a ratchet wheel 30 secured to one of t e feeders 24. The actuating rod has a laterally extending arm 26a formed on or secured thereto, whichr arm is normally held, by means of a spring 31, in engagement with the outer surface of the tube 15 as indicated in full lines in Fig. 8. The lower end of `this tube is provided with a cam 32 adapted toy engage the arm E 26, when the handle 6 and thus the tube 15 is raised, to swing it 'sufficiently to cause the ratchet wheel and thus the Jfeeders to be rotated one tooth forward. This movement causes a. nailfwhich has been fed by gravity from the ho per 18 into the feed chamber 17, to be forced aterally, by the alined teeth a of the feeders, see Fig. 8, through the feed chamber 17 and into the bore of the .base 16 where it drops by gravity. This same movement causes the teeth b of .the feeders to engage and single out the first nail from the column of nails lying in the chamber' 17 and move it forward so that on the next partial rotation of the feeders it will be fed forward into the bore of the base 16.

,To prevent lateral movement ofthe lower ends of the nails in the chambers, and to prevent the nails striking 4the base and bouncing back into the chamber' I provide the lower end of the hopper, the

chambers

17 and 17 and the communication between the chamber 1.7 and the base 16 with a channel 33 (see Figs. 1 and 7) of greater width than the remainder of these parts and adapted to receive the heads of the nails. As the nail is forced forward by the feeders 24 it ydrops into the tubular base 16 as hereinbefore described, but as the lower end of the communication between the bore of the latter and the chamber 17 is of less width than the width of the channel, the head of the nan prevents lateral movement of the nail with# in the bore of the base.

The nail is positioned in axial alinement` with the plunger 14 by means of its head engaging the bore of the base 16 and its point enaging a centering groove 34 formed in each of a pair of fingers 35. These fingers are pivotally mounted on lugs formed on the lower end of the base 16 and have their lower ends projecting through a slot formed in the lower end of the base (see Fig. l1).

l Springs 36 of any suitable shape are ada ted to engage the base and the upper ends o the fingers to normally hold the lower ends of the latter in contact with one another and thus centrally position the grooves 34. When the nail receives its first blow, the

springs permit the fingers to Slightly separate to permit the passage ofthe stem of the nail between them. s

To swing the lower ends' of the fingers 35 clear of the head of the nail, the lower end same size as the head of the nail to obtain of the tube 15 is provided with oppositely directed extensions having inclined faces 36 formed therein adapted to engage the upper ends of the fingers and squeeze them towards one another (see Fig.

To permit the use of various lengths of spikes or nails having the same sized heads,

the hopper is provided with a plurality ofsets of

grooves

37 and 37. Each set of these grooves is adapted to receive and position a false bottom (not shown) for the hopper so that lthe heads of the nails will be positioned for 'entry into the channel 33.

As hereinbefore mentioned, the tube is removably carried by the cylinder 1, a set screw 38 being provided to hold these parts together, the purpose of this arrangement is to enable the same cylinder and hammer to be used with various sized plungers and bases 16 which have to be substantially'the the best results.

Assuming nails have been placed in the v hopper and the lower end of the base 16 set against the board to be nailed, the mode of operation is as follows. The handle is raised te the position shown in lig. 1. which causes the actuating rod 26 to be functioned by the cam 32 to move the feeders to single out the forward nail in the feed chamber and position it so that when the actuating rod -is again actuated by the cam 32 the.

nail will be forced into the bore of the base 16 and a second nail will be singled out and positioned for feeding when the handle 6 is again raised to its upper position. This does not occur until the first nail is driven home. and it' will be understood that only the first nail requires two movements of the rod 26 to position it for engagement with the plunger 14. The handle 6 is then lowered until the plunger engages the head of the neil. the cylinder 1 being supported by the After each blow of the hammer is imparted tothe nail, the

plunger rests 'on the head-thereof and the tube 15 is slid farther down on the base 16. This tube is yassisted in its downward move-yk inent by means ofthe fluid pressure on the bottom of the cylinder when the hammer is being returnedto the top ofthe cylinder. When the lowerend of the tube gets near the shoulder 16, the fingers 35 are engaged by the. inclined faces 36 and squeezed together to permit -thevhead of the naillto pass lbetween them. When the nail is driven home, the Huid valve is manually closed.

and the handle 6 raised to its upper position, which causes the cam 32 to actuate the rod. 26 to cause a partial rotation of the feeders 24 to feed the second nail into the bore of the base 16 andk at the same `time to singleout the third nail and position'it for feeding.

' When the device'is used for drivin large nails or spikes, a foot rest 39, suitab y carriedl on 'the lower end of the tube 15, enables the operator to hold the ,device to its uio work. The foot rest is adapted to bethrownf.

back out of they way or removed `when not required. It will be understood that, while i i the terms nail and nail-set have 4been used throughout the specification, thedevieemay tok whichV it is suited.

1. In a device of the class describedthe be used for rivetingor any other purposel combination of a base havinga passage-- therein; a fluid pressure means including s. cylinder slidably mounted on the base; a hammer adaptedI to drive a nail; means for feeding one nail at a time into the base passage; a pair of fingers pivoted at the lower -end of the base and normally -adapted to contact with one another to center the int of the'nail; and means carried on the `ower end of the cylinder to open the said fingers to permit the passage of the nail head therebetween.

2. In a device of the class described the combination of a base having a .passage therein; fluid pressure .means including a cylinder slidab y mounted on the base; a hammer adapted to drive a nail; means for feeding one nail at a time into the base passage; a pair of fingers pivoted on the lower t e base and provided with a centerend of ing groove adapted to receive the point of a 130 nail, the base being provided with a slot'to receive the said ngers; springs adapted to normally hold the fingers in contact with one another to centerthe point of the nail;

and means carried on the lower end of the' cylinder to open the said fingers to permit the passage of the nail headtherebetween. 3. In a device of the lclassdescribed the combination of a base having 'a passage therein; fluid pressuremeans including :a cylinder slidably mounted on the base; a hammer adapted to drive a 'nail;-'means for feeding one nail at a timeinto the base passage; apair of fingers pivoted intermediate their ends adjacent the lower end of the base and provided with centering grooves adapted to receive the point. of a nail, the

vbase being provided 'with 2a slotto receive `the said fingers; springs adapted to engage the upper ends of the v.fingerstofnormally holdthe lowerends thereof `contact with one another to 'center the said nail point; andmeans carried on thelower end ofthe cylinder for engaging'. the upper ends of the said fingers to spread apart the lower-ends thereof to permit the head ofthe nail to pass through the 'end ofl the base passage.

4. In a device of the class deseribedthe combination of a base lhaving a *passage therethrough; a chamber carried by theV base communicating with the 7passage thereof; fluid'pr'essure means adapted to drivelanail including' a cylinder slidable on the said base; means vfor feeding one'nailat a time from the chamber into the base passage; ratchet means for operatin'gthe said feeding means; an actuating rod foroperating `the said ratchet means.;'and a cam `carried by 4the saidy Cylinderand adapted to engage the actuating rodto operate'the feeding means; when the cylinder is raised to positionthe fluid pressuremeansfor engagement with-Ia., fresh nail.

v5.; In a device of the class described the combination of a base having a. passage therethrough; ya chamber carried by the base communicating -with the "passage thereof; fluid pressure means adapted "to drive a nail including acylinder; a ytube detachably connected withthe cylinder and slidably mounted on the base, the tube having a slot adapted to provide clearance A-f-or the chamber and provided with a cam; a pair `of rotatable feeders adapted to engage a :nia-il. in the chamber; a ratchet yvvheelsecured to one of the feeders; `a dog adapted to pick the ratchet wheel ;-and\an-actuating rod adapted to operate the dog andnormallyfheld in engagement with the outer surface `of the tube andadapted to be engaged `-byfthe'said ca m to cause the nail` to be forced from thechamber 4into the basepassage. i

6. In a device ofthe 'class described the combination `of a tubular base; la chamber carriedv by the baseand communicating with yable by the said cam.

the vbore thereof; fluid pressure means adapted to drive a nail includin a cylinder; an axially` alined tube detachab y connected therewith and slidably mounted on the tubularbase, the tube having a slot adapted to provide 'clearance for tlie chamber, a pin and slot connection between the 'tube and the base for positioning the slot relative to the chamber and for limiting the upward movement-of the tube relative to the base; and means for feeding one nail at a time from the chamber into the boreof .the base.

7.111 a device of the class described the combination of a tubular base; a chamber carried by the base and communicating with the bore thereof; fluid pressure means adapted todrive a nail includ-ing a cylinder; an axially alined tube detachably connected base for positioning the slot relative to the ychamber and for limiting the upward movement of the tube relative to the base; means vfor feeding one nail at a timefrom the chamber into the bore of the base; and means for automatically actuating the feeding means, when the fluid pressure means is raised to position it for engagement with a vfresh nail. 4 8. In; a device of the class 'described the combination of a tubular base; a chamber carried by the said base and communicating with the bore thereof; fluid pressure means adapted to drive ya nail including acylinder having an axially alined tube detachably connected therewith, the tube being slidably mounted on the tubular base and being slottedto provide clearance for the chamber; and a pin and slot connection between the tube and the base for positioning the slot relative to the chamber and for limiting the upward movement of the tube relative to the base.

9. In a device of the class described the combination of a tubular base; a chamber carried by the said base and communicating with the bore thereof; fluid pressure means ada ted to drive a nail including a cylinder having an axially alined tube detachably connected therewith, the tube being slidably mounted on the tubular base and being vslotted to provide clearance for the chamvfrom the chamber into the base bore; and

means for actuating the feeding means oper- 10. In a device of the class described the combination of a tubular base; a chamber carried by the said base and communicating the tube having a slot adapted to with the bore thereof, fluid ressure means adapted to drive a nail inclu ing a cylinder having an axially alined vtube detachably connected therewith, the tube being slidably mounted on the tubular base and being slotted to provide clearance for thechamber I and provided with a cam at its lower end; a

pin and slot connection between the tube and the base for positioning the slot relative to the chamber and for limiting the upward movement of the tube relative to the base; means for feeding one nail at a time from the chamber into the base bore; means for actuating the feeding means operable by the said cam; fingers adapted to engage the point of a nail to center it in the bore of the base; and means carried by the lower end of the tube for spreading the fingers apart to permit the passage of the nail head between t em.

11. The combination of a base having a passage therethrough; a tube slidably mounted on the. base; a nail set slidably mounted in the said passage; movable fingers carried on the base and adapted to center the point of a nail lying in the base passage; and releasing means carried on the tube for spreading the fingers apart, the tube being adapted to follow the driven movement o the nail set whereby the releasing means will actuate the fingers to provide clearance for the nail head. Y

12. The combination of a base havin a passage therethrough; a tube slidaly mounted on the base; a nail set slidably mounted in the said passage; fingers pivoted intermediate their ends on the base and having their lower ends adapted to contact with one another to centrally locate the point of a nail; and releasing means carried on the tube adapted to engage the upper ends of the said ngers to spread their lower ends apart, the tube being adapted to follow the driven movement of the nail set whereby the re-` leasing means will actuate the fingers to provide clearance for the nail head.

' 13. In a device of the class described the combination of a base;la feed chamberi connected therewith; a magazine comprising detachably connected curved tubular sec# tions;` and a hopper adapted to be detachably connected with the cuter end of any one of the sections to enable the device to be used at various angles to its work. t Si ed at Toronto, Canada, this 29th day of arch, 1924.

JOSEPH A. C. ROBERTSON.