US 2783790 A
Description (OCR text may contain errors)
March 5, 1957 T. B. KEESLING T 2,
POWER OPERATED TOOL. ATTACHMENT FOR ELECTRIC DRILLS AND THE LIKE;
Filed Feb. 24, 1954 T 35a FIG-.3. 13
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lNVENTO/Q mow/A: BKEL'SL/A/G BY 14 .QM Arm/away United t res Patent v POWER OPERATED TGOL ATTACHMENT FOR ELECTRIC DRILLS AND THE LIKE Thomas B. Kees ling, Los Gatos, Calif., assignor of onehalf to C. H. Keesling, San Jose, Calif.
Application February 24,1954, Serial No. 412,359
Claims. (Cl. 143-68) .The present invention relates to power-operated reciprocating tools, such as saws, and is concerned more particularly with a power operated tool attachment for drive means such as an electric drill, which can be manually controlled in application to the work.
This application is a continuation in part of my copending application Serial No. 323,370, filed December 1,. 1952.
It is the general object of the invention to provide a power operated saw attachment of the above character of improved construction and economical design.
It is a still further object of the invention to provide a power operated attachment of the above character hav ing improved means for shielding the working parts from particles.
Other objects and advantages of the invention will be apparent from the following description of a preferred embodimentthereof, as illustrated in the accompanying drawings, in which:
Figure 1 is an elevational view of the saw.
Fig. 2 is a sectional view taken on the line 22 in Figure 1.
Figure 3 is an elevational view-of the saw with the cover portion of the body removed.
Figure 4 isjasectional view taken in a plane indicated by the line 4-4 in Figure 2. 1
Figure 5 is an end elevational view taken in a plane indicated by the line 5-5 in Figure 2.
Figure 6 is a fragmentary elevational view of the cover-V I r.
Figure 7 is aperspective view of the saw clamping head shown'in exploded fashion.
Figure 8 is an elevational view of the dirt shield.
Figure 9 is a sectional view taken on the line 9-9 in Figure 8.
Figure 10 is a fragmentary sectional view illustrating a modified form of dirt shield. I
The power-operated hand-controlled tool ofthe instant invention comprises a body including a body 10 and a cover 11 both of die'cast construction whose parting line lies in a plane parallel to certain working parts of the tool including a reciprocating drive link 12. The cover 11 (Figures 2 and 6) is provided about its periphery-with a flat surface 16'which engages flush with a corresponding peripheral edge surface 17 of the body 10. The cover 11 is also provided with an inwardly spaced outwardly projecting rib 18 which seats within a recessed portion 19 of the body in flush engagement with the side wall 21 adjacent the flat peripheral edge portion 17. As seen in Figure 6, the front end portions of the rib 18 of the cover 11 merge with a bearing pad 36 for the reciprocating elements of the tool. The cover 11 is provided with four threaded apertures 22 to receive the threaded ends of a socket cap screws 23 seated in corresponding aligned apertures 24 of the base 10.
The body 10 (Figure 2) is provided with a boss or extension 26 to journal internally threaded drive thimble I 2,783,790 Patented Mar, 5, 1957 I 2 end face of boss 26. The other end face of boss 26 is engaged by a drive disc 28 secured to and against the end of thimble 27 by a threaded extension 28a. A chucking shaft 30 is threaded into the thimble 27 and is provided with a hexagonal collar 30a for engaging the thimble 27. The driver or disc 28 carries an eccentric drive pin 31 by which it is pivoted to the rearward end of the drive link 12. The drive link 12 is guided by an integral pad of bearing portion or pad 36 at its front end, where it is connected by a pivot pin 33 carried in a slide 34. The slide 34 is mounted for longitudinal movement in a track formed by side. walls 35 of the body, is supported at its lower side by walls 35a adjacent sidewalls 35 and by a pad 37 of the body 10. The slide 34 is engaged by the side guide flanges 39a of a channel-shaped, clamping head 39 of sheet metal construction, which flanges are also guided in the respective guide walls 41 of the body 10. As seen in Figures 3 and 7, the top wall of the head 39 has a concave recess to provide clearance for the link 12, and the side flanges 39a extend rearwardly in overlapping relation therewith. The head 39 has its upper surface engaged with the pad 36 which also guides the link 12 at its forward end. The front edges of the head 39 are made sharp and close-fitting for cleaning out of metal chips and other particles. The head 39 has as a part of its structure an insert plate or spacer 42 which is interposed between the head and the saw blade 47 when the blade is clamped in place. This plate 42 has a suitable central aperture to engage over the counters sunk portion of the head and is notched to engage a downwardly formed ear 3% of the head, the ear 39b and the cooperating notch forming interlocking portions to maintain the position of the parts. By employing plates 42 of suitable thickness tools of differing thickness can be secured in place in the head.
The head 39 (Figures 2, 4 and 7) forms a part of the saw securing means or clamp and for this purpose has a countersunk recess receiving a clamping screw 46 threaded into the slide 34. Clearance for the end of screw 46 is provided by a recess 38 in pad or surface 37. The saw 47 is clamped between spacer plate 42 of the head 39 and the slide 34, the saw having a longitudinal slot47a which enables endwise positioning of the saw over the screw 46. The molded recess 48 of the cover provides for access to the screw 46 in the extended positionof the saw as seen in Figure 2. The straight side edges 47b engage the inner surfaces of the side flanges 39a of the head 39. The shoe 51 forms a work guide or work-engaging piece and is formed with a front edge 51a which is perpendicular to the path of movement of the slide 34 and the head 39 and end portions 51b bent to form an included angle of less than degrees The saw blade 47 is" thus mounted for a'straight line movement-with theslide 34 having its edges confined by the side flanges 39a of the head as seen in Figure 4 so that the saw is definitely located in place and is securely held in performing the work.
Referring to Figures 1, 2, 3, 8 and 9, a dust or dirt shield 56 is shown which is interposed between the teeth of the saw blade 47 and the head 39 and the slide 34. The shield 56 is preferably formed of a resilient flexible material such as synthetic rubber and is provided with a central slit 57 to engage closely over the saw, this slit 57 merging with inclined recessed walls 58a opening to ward the operating parts for the saw including the slide 34 and the head 39. The shield 56 is also provided with 27 having a hexagonal flange portion 27a engaging one apertures 58 which engage over the two ends of the shoe 51 to secure the shield in place stretched across the end of "the saw attachment. As seen in Figure "3, for example with the slide 34 projected the shield 56 is stretched slightly, so that as the slide .34 and the head.39.recipro care, they vibrate the shield to dislodge particles resulting from the sawing operation from the .face thereof. The slit 57 engages closely over blade 47 and tends to open as the blade moves outwardly and to close as it moves inwardly. The tendency of the lips to flex and grasp the blade as it moves inwardly 'is enhanced by the recessed construction provided by the beveled walls 58.2, which extend through .a major portion of the thickness so as to provide thin lips.
In Figure 10 there is shown a modified form of shield 59 having outwardly projecting taperedlips 59a defining the slit engaging the saw blade. The shield 59 also has tapering molded side walls 59b around its-entire periphery for engagir walls of the body 10 and the cover 11. The recess 3 is only partially .covered by the wall 5912 so that access can be had to the screw 46. The shield '59 is secured on the saw attachment in thesame manner as the shield 56 and functions inthe same manner with respect to the saw blade.
Referring to Figures 1 and 3 it is seen .thatthe body and cover form together concave hand grip portions 53 whereby the tool may be gripped in onehand and the other hand can carry the handle of a power drill with which it is used. If it is used with a fiexibleshaft drive,
both hands may be employed in holding the tool with respect to the work.
While 1 have shown and-described a preferred embodiment of the invention,'it will be understood that the invention is capable of variations and modification from the particular form shown, so that its scope should be lim ited only by the scope of the claims appended hereto.
1. In an attachment for a portable electric drill and the like, a body structure of elongated longitudinal shape forming a hand grip, said body structure having an apertured boss disposed transverse to the direction of elongation thereof, guide means extending longitudinally of said body structure, a reciprocatory slide mounted in said guide means, means for detachably securing a working tool to said slide, and means for operating said slide including a chucking shaft journalled in said boss, said chucking shaft providing for connection to an electric drill, and also providing a pivot axis about which said body structure can be freely rotatively adjusted during use of the attachment.
2. In an attachment for a portable electric drill, a body of elongated shape having an apertured boss disposed transverse to the direction of elongation and also having guide means extending longitudinally thereof, a cover for said body. having pad portions opposed to the guide means of said body, means for securing the cover on the body, operating means in said body including a chucking shaft journalled in said boss and a slide driven by said shaft, said shaft providing a pivot axis for said attachment, 2. tool, a tool clamping head releasably secured to said slide, said head being channel-shaped and having guide portions, each guide portion engaging freely over an edge of the slide on one side and slidably engaging the guide means in the body on the other, and se. curing means extending through said head and said slide and clamping the tool therebetween.
3. In an attachment for a portable electric drill, a body of elongated longitudinal shape forming a hand grip and having a boss transverse to the direction of elongation, said body also having integrally formed guide means extending longitudinally thereof, a cover for said body and similarly elongated, and said cover having pad portions opposed to the guide means of said body, 'a reciprocatory slide mounted in'the guide means of said body and engaged by said pad portions, drive means in Said boss for said slide including a chucking shaft, and means for detachably securing a 'Workingtool to said slide, said chucking shaft providing for connection to an electric drill, and also providing a pivot axis about which said body structure can be freely rotatively adjusted during use of the attachment.
4. In an attachment for a portable electric drill a body of elongated longitudinalshape having a boss transverse to the direction .of elongation, a cover for said body similarly elongated, saidbody and said :cover being symmetrical with respect to a longitudinal plane disposed centrally thereof'and parallel to the axis of said boss to form a hand grip, a reciprocatory slide mounted in said body for reciprocation longitudinally of said body, drive means for said slide including a chucking shaft-mounted in said boss having a drive connection to said slide, and means for detachably securing a working tool to said slide, said chucking shaft providing for connection to .an electric drill, and also providing a pivot axis about which said body structurecan be freely rotatively adjusted during use of the attachment.
5. A tool attachment as recited in claim 1 in which said securing means includes a channel shaped clamping head to receive the tool, a spacer plate received within the head for clamping engagement with the tool, and se- References (Jited in the file of this'patent UNITED STATES PATENTS 938,680 Martin Nov. 2, 1909 1,116,640 Sporleder Nov. 10, 1914 1,322,873 Brull Nov. 25, 1919 1,569,301 Reed Jan. 12,1926 1,679,884 Thomas Aug. '7, 1928 1,698,788 Gibson Jan. 15., 1929 1,793,053 Cahill et al. Feb. 17, ,1931 1,826,188 Pickering et al'. Oct. .6, 1931 2,143,981 Harding Jan. '17, 1939 2,146,777 Strong Feb. 14, 1939 2,452,148 Rhodes Oct. 26, 1948 2,619,132 Pierce Nov. 25, 1952 2,668,567 Olson Feb. 9, 1954 FOREIGN PATENTS 208,301 Switzerland .Apr. 16, 1940 916,733 France Aug. 26, 1946 and...