AU593585B2 - Space cleaning impact tool - Google Patents

Description

ranas~ AU-AI 63 7 8 6 WORLD INTELLECTUAL PROP OIZ q 5 84 Internationtl B 4. 4 PCT INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 4 (11) International Publication Number: WO 87/ 01325 15/00, 15/02, 17/20 Al (43) International Publication Date: 12 March 1987 (12.03.87) (21) International Application Number: PCT/AU86/00268 (81) Designated States: AT (European patent), AU, BE (European patent), CH (European patent), DE (Euro- (22) International Filing Date: 10 September 1986 (10.09.86) pean patent), FI, FR (European patent), GB (European patent), IT (European patent), JP, LU (European patent), NL (European patent), SE (European (31) Priority Application Numbers: PH 2360 patent), US.

PH 2911 (32) Priority Dates: 10 September 1985 (10.09.85) Published October 1985 (15.10.85) With international search report.

Before the expiration of the time limit for amending the (33) Priority Country AU claims and to be republished in the event of the receipt of amendments.

(71)(72) Applicant and Inventor: ISENRING, Fritz, Niklaus [AU/AU]; Cnr. Beak Butler Streets, Clinton Heights, Gladstone, QLD 4680 A P. 3 0 APR 1987 (74) Agent: FISHER, Peter, Cullen Halford Maxwell, 82 Ann Street, Brisbane, QLD 4000

AUSIRAIAN

Thiis document contains the 2 4 MAR 8187 anmslndniants imade under Section 49 and is correct for PATENT OFFICE printing,.

(54) Title: IMPACT DEVICE 7- 10 11 -9 .12 8 1 .19 (57) Ab:tract An impact tool comprises a housing having a hollow cylindrical ap'rture therein and a rotatabl. member ro.

tatable about an axis coaxial with a central axis of the cylindrical aperture, the rotatable member comprising radially spaced rods supported by end plates Captively located on the rods are annular masses (10) wi(h a central aperture of larger diameter than the rods to permit radial movement of the masses (10) relative to the rod The rotatable member is driven by a motor and as it rotates the masses (10) strike impact tools supported in a housing extension and impart kinetic energy to the impact tools ~ii~i WO 8701325 PCT/AU86/00268 "IMPACT DEVICE" The present invention relates to improvements in impact devices and particularly although not exclusively to needle guns.

Needle guns generally comprise a number of hardened steel rods or "needles", tapered at one ekd and retainably mounted in a housing with the tapered or pointed ends extending outwardly. The retained ends of the needles are subjected to a "hammering" action to generally by a rotating hammer or anvil device.

Needle guns and impact chisels may be used for a variety of purposes including removal of rust, dirt, paint or other coatings from surfaces prior to painting or other treatment. In addition, welding slag is readily removable from welded surfaces by the use of a needle gun or impact chisel. Needle guns have been found to be particularly suitable for roughening the surface of cured concrete where reconcreting is required.

Previously known impacting devices such as needle guns scalers, chippers and the like have hitherto suffered a number of serious disadvantages.

Prior art devices have been either large, cumbersome and heavy to operate, they suffered from considerable vibration, they were subject to inordinately rapid Swear, or most usually they suffered from combinations of the above problems. Such prior art devices are exemplified in United States Patent No. 3193908, i 2 Australian Patent No. 154157, French Patent No. 874708 and German Patent Nos. 442532, 463948.

In an endeavour to overcome or at least alleviate the problems of prior art impact devices there has been proposed a device employing a plurality of inertia members in the form of steel balls movable in radially bored recesses in a rotatable member. This is described in my European Patent No. 058 677.

S The present invention is herein particularly S described as applied to an impact tool in the form of a needle gun, chipper, scaler or the like, but the 0g S.

SS invention is equally applicable to other impact tools *se such as hammers, drills and chisels.

According to the invention there is provided an impact tool comprising a housing, a rotary member se mounted within said housing for rotation about a fixed axis and including a plurality of axially-extending retaining elements spaced about rings captively mounted *sees: on said retaining elements, each of said rings having a 0555 S central circular aperture the diameter of which is .se greater than the diameter of the associated retaining element whereby the ring can move radially relative to the retaining element, and impact means mounted to be struck by the rings, whereby in use, rotation of said rotatable member causes impact energy to be imparted to said impact means by the said energy transfer rings.

C, ~lrE -3- According to a preferred feature of the invention said retaining elements comprise shafts equiangularly spaced about said axis and disposed parallel to said axis, said shafts having their two ends secured to respective rotary carriers.

Preferably a plurality of said rings are mounted on each of said retaining elements and are axially spaced from each other, conveniently by lowfriction discs mounted on the elements.

According to another preferred feature of the .invention, the rings on the retaining elements are arranged in one or more helical arrays.

In order that the invention may be more readily understood reference will be made to preferred 15 embodiments described in the accompanying drawings in which: FIG 1 is a side elevation of a first impact tool according to the invention 0 FIG 2 is an end elevation of the tool shown in 0 FIG 1 0 20 FIG 3 is a cross section along A-A in FIG 2 FIG 4 is a cross section along B-B in FIG 2 FIG 4 is a cross section along B-B in FIG 2 SFIG 5 is a cross section along C-C in FIG 1 FIG 6 shows an alternative embodiment in corss section corresponding to the plane A-A of FIG 2 Qi 1 ,I WO 87/01325 PCT/AU86/00268 FIG 7 shows a cross section along B-B in FIG 2 of the alternative embodiment.

FIG 8 shows a cross section along D-D in FIG 2 of the alternative embodiment.

FIG 9 shows a side elevation of yet another embodiment.

FIG 10 shows an end elevation of the device of FIG 9.

FIG 11 is a cross section through A-A in FIG FIG 12 is a cross section through C-C in FIG 9.

FIG 13 is a cross section through B-B in FIG FIG 14 is a plan view of a needle module.

FIG 15 shows a gouging tool suitable for use with the invention.

FIG 16 is a cross section through D-D in FIG In FIG 1 the apparatus comprises a body 1 having a flange or mounting lugs 2 for attachment of an electric drive motor and housing assembly 3. The 2 housing 3 is adapted for use as a hand grip. A lower body extension 4 serves as an attachment means and guide for needles FIG 2 shows an end elevation of the apparatus of FIG 1 when viewed from the end of body 1.

FIG 3 is a cross section along A-A of FIG 2. L i k

A.

WO 87/01a325 PCT/AU86/00268 Rotatably mounted within body 1 is a cage-like rotatable member 6 comprising end members 7 and 8 connected by retaining member shafts 9. Captively mounted on shafts 9 are energy transfer members in the form of thick annular discs 10. The diameter of shafts 9 is considerably less than the diameter of the central apertures 11 in discs 10 thereby allowing discs 10 to move in a radial direction while remaining captive.

The discs 10 are arranged in a helical array on the three shafts 9 as shown in FIG 5. Each disc is separated from an adjacent disc 10 by separator plates 12 which constrain each disc to move in a fixed rotary path or radial plane. The separator plates are of metal or a durable low friction plastics material to facilitate free movement of the discs 10 about respective shafts 9 without friction losses between adjacent discs.

The rotatable member 6 is at one end mounted for rotation in body 1 by a stub axle 13 journalled in a roller bearing 14 in end member 7. Rotatable member 6 is similarly mounted at its other end by a stub axle journalled in a roller bearing 16 in end member 8.

End member 8 is formed as a drive gear having internal teeth 17 which engage the teeth of pinion gear 18 formed in the end of the drive shaft 19 of motor assembly 3. An end cap 20 closes the body 1.

FIG 4 shows the cross section along B-B in FIG Chipping or scaling needles 5 are mounted in body 1 i i i ;i r f i b j Ci 6 extension 4 which includes guide apertures 21 at the upper end 22 and lower end 23 of extension 4.

Referring to FIG 5 it can be seen that the needles are mounted in groups of six, each group having an intermediate follower 24 slidably mounted in a follower guide Needles 5 are preferably resiliently biassed by a spring means to a retracted position shown generally by the position of the top'of follower 24 shown at 24a. For the S i6 sake of clarity all other needles and followers are shown in the extended position and the spring means in the form of helical coil springs are omitted.

In FIG 5 it can be seen that the rotational axis of rotatable member 6 is offset from the lines of sliding movement of followers 24.

In use, as the rotatable member 6 is caused to rotate by electric drive motur assembly 3, discs 10 are urged outwardly under the effects of centrifugal force. The discs 10 strike followers 24 and transfer a substantial part sees** of their kinetic energy to the followers which in turn •*eg transfer the energy to the needles as an impact.

The helical array of discs 10 permits a progressive striking action on the needles thus substantially reducing the vibration normally associated with needle guns. Should one group of needles be prevented from being fully extended by an f t r

P

i "i 1 r. WO 87/0,1325 -4 PCT/AU86/00268 irregularity on a surface being treated, the disc 10 is still able to impart an impact on that group of needles due to the difference in respective diameters of shaft 9 and disc aperture 11.

Figures 6-8 show an alternative embodiment of the invention wherein for each follower 24 an array of two diametrically opposed discs 10 are mounted on the retainer shafts 9 of a rotatable member having six retainer shafts. Adjacent paired arrays of discs 101 are arranged in a helical fashion as with the embodiment of FIGS 3-5. It can be seen that for the same operating speeds the rate of impacting is increased by a factor of two.

FIGS 9-16 show yet another embodiment of the invention.

FIGS 9 and 10 respectively show side and end elevations of the apparatus FIG 11 is a cross section through A-A in FIG This embodiment differs from that shown in FIG 3 in that the separator plates 12 of FIG 3 are omitted.

As the successive discs 10 overlap it is not necessary to have separator plates but some form of separation is preferred. In lieu of separator plates, spacers 30 are employed. These spacers are of variable length due to the helical disposition of discs 10 about shafts 9.

The spacers 30 comprise cylindrical steel members having a diameter less than discs 10 and each includes an eccentrically bored aperture 31 for mounting the SO 87/01325 8 PCT/AU86/00268 spacers 30 on shafts 9. The diameter of aperture 31 .is slightly larger than that of shaft 9 to permit a smooth sliding fit thereon. Rotatable member 6 is driven by a drive shaft 32 (connected to a suitable drive means) via pinion 33 and a drive gear 34 formed integrally in -nd member 8 of rotatable member 6.

FIG 12 is a cross section through C-C in FIG 9. Although spacers 30 are rotatably mounted on an eccentric axis on shafts 9, in use, centrifugal force will cause the spacers to adopt the configuration shown in FIG 12. In this manner additional mass is concentrated towards the periphery of rotatable member 6 thereby enabling in use an increase in rotational momentum without a proportional increase in mass of the device. The pirvotally mounted spacers 30 effectively act as shock absorbers and it will be found in use that very little of the uncomfortable vibration associated with prior art devices is transmitted via body 1 or motor housing 3 to a user.

FIG 12 shows the mounting of the needles Into body 1 are mounted studs 36 having a threaded spigot 37 on one end and a threaded socket 38 on the other end. Studs 36 serve to retain a guide 39 for ,follower 40. An intermediate follower 41 mounted between follower 40 and the heads 42 of the needles 35. Intermediate follower 41 inclludes semicircular apertures at its opposed ends and these apertures align LL with the opposed studs 36 to guide the sliding path of S* i s i 1 1 1 WO 87/01325 PCT/AL'86/00268 intermediate followers 41. The needles 35 are mounted in groups of say 22 in a collar 43 slidably mounted on studs 36. FIG 14 shows a plan view of collar 43 with apertures 44 in which studs slidably locate the collar 43. Helical springs 44 are located around studs 36 to bias collar 43, intermediate follower 41 and follower towards the rotating discs 10. A lower retaining plate 45 serves as a lower guide for needles 35 and a retainer for springs 44. Plate 45 is retained by threaded screws located in sockets 38 on each alternate stud 36. A dust seal in the form of a lubricated felt pad 47 is retained by a shim plate 48 which in turn is retained by body extension housing 49 and screws located in alternate sockets 38.

FIG 13 shows an enlarged partial cross section through B-B in FIG FIG 15 shows an alternate form of tool 51 which may be suitable for gouging holes in a surface such as brick or concrete walls for insertion of electrical wiring or the like. The impact device is simply moved along a predetermined path to cut an elongate groove in the surface.

The tool 51 comprises a shank 52 a follower 53 and a gouging bit 54. Bit 54 comprises a thin walled tubular member 55 having an elongate slot 56 extending lengthwise thereof to enable removal of material gouged by the end of the bit 54. FIG 16 shows a cross section through D-D.

S

T 1 1 e i t WO 87/01325 PCT/AU86/00268 Devices according to the invention may be in the form of portable hand held devices driven by electrib or fluid powered motors for the removal of scale, rust, welding slag, paint etc from surfaces.

With fluid powered motors they may be used in aggressive or dangerous environments or they could be used underwater e.g. in removal of rust, scale or marine growth on ships or marine structures.

In other forms the apparatus may be in an elongate form to descale planar objects such as sheet steel or the like. The elongate apparatus may be arranged transversely to the direction of motion of a sheet of steel emerging from a steel rolling mill or the like. The apparatus may also be adapted for treatment of rolled steel products as a post rolling or pre-rolling surface treatment.

In yet a further embodiment the apparatus may be adapted for mounting on a mobile vehicle for breaking road surfaces or demolishing structures.

It will be readily apparent to a skilled addressee that many modifications and variations are possible with the present invention without departing from the spirit and scope thereof.

U1 A

S,.

Claims (9)

1. An impact tool comprising a housing, a rotary member mounted within said housing for rotation about a fixed axis and including a plurality of axially- extending retaining elements spaced about rings captively mounted on said retaining elements, each of said rings having a central circular aperture the diameter of which is greater than the diameter of the 0* *associated retaining element whereby the ring can move \radially relative to the retaining element, and impact means mounted to be struck by the rings, whereby in use, rotation of said rotatable member causes impact energy to be imparted to said impact means by the said energy transfer rings. 0.0,

2. An impact tool as claimed in claim 1, wherein said retaining elements comprise shafts equi-angularly 000o0 spaced about said axis and disposed parallel to said OO0•O: axis, said shafts having their two ends secured to 0000 respective rotary carriers.

3. An impact tool as claimed in claim 1 or claim 2, wherein a plurality of said rings are mounted on each of said retaining elements and are axially spaced from each other. PLU rl:: i 1 i 12

4. An impact tool as claimed in claim 3, wherein the rings on each retaining element are axially spaced from each other by low-function discs mounted on the elements. S

5. An impact tool as claimed on any one of the preceding claims, wherein the rings on the retaining elements are arranged in one or more helical arrays.

6. An impact tool as claimed in any one of the 0S preceding claims, wherein the impact means are mounted S 10 for linear sliding movement in a plane or planes r. parallel to but laterally offset from said axis.

7. An impact tool comprising a housing, a rotary cage mounted in the housing and comprising two parallel end members and a plurality of axially-extending 15 retaining shafts each having it opposite ends secured to the two end members respectively, the cage being rotatable about its central axis and the retaining rIr0 So shafts being equi-angularly circumferentially spaced about the central axis, a plurality of energy 20 transmitting rings each having a central aperture S0 00 through which one of the shafts extends and the diameter of which is greater than the diameter of the shaft, and a plurality of impact elements arranged in line parallel to said central axis and mounted for sliding movement in a plane offset from said central axis, said .~U F, V 13 impact elements each having one end disposed so as to be struck by at least one of said rings during each revolution of the cage.

8. An impact tool as claimed in claim 7, wherein the shafts are arranged in pairs the two shafts of each pair being diametrically opposite each other and wherein each of the two shafts carries an energy transmission ring disposed in the same radial plane as -the ring carried by the other of the two shafts. 10

9. An impact tool as claimed in claim 7, wherein all the shafts carry equal numbers of rings and wherein the rings are disposed in a helical array on the cage. 0* b S .0 06 SO S. 00 550 0. d S a 05 S a DAIMD this 28th day cf November 1989. FRITZ NIKLAJS ISENRING By his Patent Attorneys I G.R. CULLEN COMPANY 0 TS 0O08U0 *ell *SSS