US1932723A

US1932723A - Vibratory tool

Info

Publication number: US1932723A
Application number: US303703A
Authority: US
Inventors: Hugh S Brown
Original assignee: Individual
Current assignee: Individual
Priority date: 1928-09-04
Filing date: 1928-09-04
Publication date: 1933-10-31
Anticipated expiration: 1950-10-31

Description

H. 5. BROWN (Jet. 31, 1933.

VIBRATORY TOOL Filed. Sept. 4, 1928 3 Sheets-Sheet l gig/f H. 8. BROWN 1,932,723

VIBRATORY TOOL Filed Sept. 4, 1928 3 Sheets-Sheet 2 Oct. 31, 1933.

villi/1111!! ill! ll Wzeaax Patented Oct. 31, 1933 f UNITED STATES PATENT OFFICE VIBRATORY TOOL Hugh S. Brown, Harvey, 1H.

7 Application September 4, 1928. Serial No. 303,703

1 Claim. (o1.125 s3) This invention relates to portable reciprocating tools, such, for example, as rock drills, 'tampers and other devices which can be handled and controlled in a convenient manner by a single operator.

It is highly desirable that devices of the above type be as light as possible'and that the vibratory impulses, except those delivered to the tool itself, be reduced. to a minimum in order that as little power as possible will be required to operate the tool and as little efiort as possible will be required to control the same.

One of the primary objects of this invention 'is accordingly to provide a vibratory tool in which the vibration through the casing is reduced to a minimum.

Another object of this invention is to provide a vibratory type of tool which is light in weight,

simple in construction and efiicient in operagot Fig; 1.

tion.

A further object of the invention is'to provide a tool of the above type in which the operating parts of the tool, except for that part which is necessary to contact the work, ar completely inclosed. A further object of the invention is to provide a vibratory type of tool employing a hammer in which the extreme withdrawal movements of the hammer are retarded by means providing an air cushion, thus reducing the amount of vibration transmitted to the casing.

A further object of this invention is to provide atool of the above character the operating parts of which are inolosed, but are readily accessible for inspection, renewal, or repair.

Other and further objects of this invention will' be apparent as the same becomes better understood from an examination of the specification and. claim in connection with the accompanying drawings, wherein Fig. 1 represents a vertical fragmentary sectional view of'a device embodying this invention.

Fig. 2 is a section taken on the line 2---2 of Fig. 1' showing parts in elevation.

Fig. 3 is a detail section with parts in elevation of the drivingv motor taken on the line 3--3 Fig. 4 is an enlarged detail view partly in section of the connecting rod for connecting the crank shaft and rocker;

Fig. 5 is a section taken onthe line 5-5 of Fig. 4, and r Fig. 6 is an enlarged detail vertical section of theadjustable plug by means of which a rocker drives the hammer on its downward stroke.

Referring to theedr'awings more particularly, numeral 7 designates a casing for the operating mechanism. This casing may be cast to provide a lower section 3 and an upper or cover section .9, .which may be bolted thereto in a suitable manner as by bolts (not shown) extending intoears formed integrally with adjacent contacting portions of the section. The section 9 is provided with an upwardly extending sleeve 11 which is adapted to receive and have secured therein apipe 12 the upper end of which is provided with a suitable handle (not shown). The housing member 9 isalso provided with a laterally projecting bracket 13 which is provided with a handle 14. By means of these handles the tool may be conveniently controlled.

The lower end of the housing section 8 is provided with a downwardly extending sleeve 15. Supported with its upper end extending into this sleeve is a tool 16, such as a drill or tamping tool. A bushing 17 is provided within the sleeve 15 for the reciprocable tool 16. This bushing acts as a bearing for an upper portion 18 of the tool 16. A collar 19 integrally formed on the tool 16 beneath the portion 18 engages an annular shoulder 21 formed by an enlargement 22 of the lower portion of, the bushing 17 to limit the upward movement of the tool 16. An annular flanged member 23 is removably secured to the open end of the sleeve 15 by means, of studs 24. A bushing 25 provided with an annular flange 26 projecting radially over the inneredge of the member 23 is carried thereby'and acts as a bearing for the lower portion of the tool 16.

be described.

Formed integrally with the casing section 8 are

bosses

29 and 31 whichsupport a pin 32.

This pin serves to pivotally support a lever or helve portion 33 of a hammer and a rocker memthroughout its travel.

-to thecasing.

her 34 concentric therewith. This rocker member is oscillated about its pivot by the driving motor through the medium of operating connections, which will presently be described. A yieldable connection is provided between the helve 33 and the rocker 34 at a position spaced from their common pivot whereby the helve may be driven with a minimum of vibration imparted to the casing. To this end I provide a yieldable plug, generally designated 35, adjustably threaded in an upper arm 36 of the rocker in a direction at right angles to the normal position of the helve.

As shown in Fig. 6, this plug 35 includes a metaL portion 3'7 threaded on its outerperiphery to cooperate with threads in the arm 36 and includes a cylindrical rubber portion'38 depending from the metal portion and formed by vulcanizing the rubber thereto. The lower end of the plug is provided with a downwardly rounded cap 39 for contacting the helve. This cap, like the metal portion of the plug is attached to the rubber during the vulcanizing process.

A screw plug 41 threaded in a lower arm 42' of :the rocker 34;.at right anglesto the normal position of the helve acts to holdthe a same against the, yieldable plug 35. ,By means ,of ,the yieldable connection .providedpby the plug 35, the .force of thehelve is not atoitsmaximum at the end of a downward or striking stroke, .but, on .the other hand, considerable potential energy isibuilt'up'within the rubber in the plug during the striking strokeandthis energyis expended .at .the end .of the stroke .as the .head of the helve strikes the upper'end of thetool 16.

..In.order..to further reduce the .vibrations impartedtothe casing, it is desirable .to'cushion rtheupperilimitsioftravel of the helve. For this epurposetheihammerheadili is in the form of a piston which :is slidable within a cylinder 44 supported betweenthesleeves 11 and 15. This head-=43 is transversely apertured orreoessed, as 'at-46, intermediate its ends, into which the free and of the helve 33-fits the freeendibeing provided withanenlarged ball shaped portion 46 which extends into the recess for connecting the helve to the head; The upper end of the cylinder is blanked'off by a disk 47 below'the pipe 12 and the cylinder is provided with a longitudinal slot48 for accommodating the-helve The travel of the head 43 extends for a considerable distance beyond the upper limit-of the slot 48, whereas it does not extend-an appreciable distancebeyondthe lower extremity of this slot. Forthis' reason, a predetermined amount ofair is compressed by the head 43 at its extreme upper limits of travel for cushioning the extreme withdrawal movements of the head and reducing the vibration imparted The mecham'sm 'for oscillating the rocker 34 will now be described. The outer lower surface of the casing secton 8 isshaped cylindrically j to form' a cradle for a driving motor 49 and casing therefor. ,The casing for thismotor 49 .is provided with a centralcircumferential groove 51 for accommodating a strap 52 by means of which the ,motor attached to the casing section 8. One end of the strap 52 is pivotally ;attached to'the latter casing section by means of a pin 53 :extendingbetween a pair-of lugs inwrallyricrmed: onsaid section. The other end vof. said strap is provided lwithalug 55 ,adaptshaft 62 mounted in the casing section 8 on spaced ball bearings 63 and 64. The ball beared to cooperate with a screw dog 56 pivotally attached to the sleeve 15.

In order that none of the moving parts of the motor or its connections to the vibratory mechanisms may be exposed, the motor is so constructed that the bearings 57 for the armature shaft are supported by the motor casing at the respective ends thereof, the ends of the shaft being entirely enclosed and the driving pinion 58 of the motor mounted on the shaft inside of one of these bearings instead of outside the motor on an outer end of the armature shaft as in the usual practice. The motor casing is provided withan opening 59 and the casing section 8 for the vibratory or operating mechanism is provided with a corresponding opening for permitting a large gear 61 mounted within the casing section 8 to mesh with the pinion 58.

The gear 61 is rigidly mounted upon a crank ing 63 is carried in a cap 65 inclosing the outer end -of the shaft 62 and bolted to the casing section 8 by means of bolts 66. An annular disk 67 fitting within cooperating recesses in the contacting surfaces of the cap 65 and casing section '8 surrounds the shaft 62 and acts to hold the ball bearing unit against an annular sh0ulder68 on the interior of'said cap whenthe bolts 66 are tightened. The ball bearing 1111113 64 is centrally carried in a,partition'69 inte- .grally formed within the section 8 in a manner to segregate the gear 61 from the rest of the interior of said section.

The inner end of the shaft 62 extends into the interior of the section 8 beyond the partition 69 and is in the form of a crank '71. A connecting rod 72 is connected at one end to the crank 71 through the intermediary of a ball bearing unit .73. The other ,end of the connecting rod 72 is enlarged and provided with a longitudinally extending opening '74 in which is vulcanized under pressure a bodyof rubber 7 5 for floating .a ,bushing'lfi. This bushing acts asa bearing for a transverse pin "17 extending through rocker member 34.

In the operation the motor may-be controlled by means of a suitable switch in proximity to either one of the handles of the device. When the motor is driven it will act through the pinion 58 and gear 61 to drife the shaft 62. This .shaft through the intermediary of the crank ,71 .and connecting rod '72 will oscillate the rocker 34. The rocker 34 acts, as previously described, to reciprocate the helve 33 and head 43 to 180 strike the tool '16.

It will be seen that by reason of the .provision of the air cushion for retarding the .extreme withdrawal movements of the head 43 considerable vibratory impulses, which would otherwise be imparted to the casing, are avoided. The yieldable connection between the rocker34 and the'helve afforded by the yieldable plug35, and the floating bearing 76 of the .connectingrod '72 also reduce thevibratory impulses imparted tothecasing. 7/ 3 An oil well'lfi is formed Within the 'wall of the casingsection 8 and runs longitudinally with respect to the cylinder 44. This well is pro -vided .with inlets 79, whereby it may be filled 1.45

.from without, and ducts 81 communicating with the interior of said cylinder for lubricating the head 43.

It will also be apparent that the aforedescribed construction is rugged-and thatit issimpie to manufacture and convenient to operate. The parts are readily accessible for inspection, renewal or repair.

I am aware that many changes may be made without departing from the principles of this invention and I therefore do not wish to be limited to the details described.

I claim:

In a portable self-contained vibratory tool, a

portable casing having a cylinder therein closed at one end and slotted at one side for a portion of its length, said slot terminating short of said closed end to form a sealed cylinder portion, a