US3131735A

US3131735A - Circle attachment for band saws

Info

Publication number: US3131735A
Application number: US210038A
Authority: US
Inventors: Janiak Alexander
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-07-16
Filing date: 1962-07-16
Publication date: 1964-05-05
Anticipated expiration: 1981-05-05

Description

May 5, 1964 A. JANIAK 'CIRCLE ATTACHMENT FOR BAND sAws Filed July 16, 1962 INVENTOR ALEXANDER JANIAK ATTORNEY FIGA FIGC

United States Patent() 3,131,735 CIRCLE ATTACHMENT FOR BAND SAWS Alexander .laniak, 9904 Walnut St., Oakland, Calif. Filed July 16, 1962, Ser. No. 210,038

. 3 Claims. (Cl. 143-26) This invention relates to improvements in means for cutting circles and other arcuate forms on conventional band saws in Which the Work-supporting table can be swung into an angular position with respect to a horizontal plane and the invention provides an attachment which is mounted on the head of a band saw and having an arm which is pivotally connected to the mounting bracket and provided with clamping means, with the arm adjustable in a vertical plane and which is to be adjusted to a planeparallel to the plane of the band saw table to provide for perpendicular cooperation of the centering pivot with the blank to be cut to form.

This attachment is of the simplest possible construction While providing the maximum rigidity for ecient operation, the angular adjustment of the arm permittingv the use of rectangular tubular sections for the various adjustable elements to maintain proper orientation between the adjustable members.

With this invention it is possible to cut discs with the peripheral edge at right angles to the faces or with the peripheral edge beveled to any desired angle, and which equally applies to other arcuate forms. j

Furthermore, a universal mounting bracket is provided as standard equipment, and which is secured on a second bracket `which is adapted to the specific band saw on which it is to be mounted, thus only the second bracket is varied for the diierent installations.

The objects and advantages of the invention are as follows:

First, to provide a circle attachment for band saws in which the centering pivot is adjustable to a position perpendicular to the blank from which a form is to be cut.

Second, to provide an attachment as outlined inwhich the perpendicular position of the centering pivot is` obtained through angular adjustment of the main supporting arm in a vertical plane. v v

Third, to provide an attachment with a main supporting arm which is pivotally mounted in a supporting bracket on a horizontal axis and provided with clamping means for securing the main supporting arm in adjusted position.

Fourth, to provide a mounting bracket which is adapted to the speciiic band saw on which it is to be mounted and to iixedly attach the supporting bracket to the mounting bracket for ease of installation and maintenance of a standard circle attachment construction.

Fifth, to provide an attachment as outlined which is universally adjustable for thickness of material, angularity of cut, radius of cut, and for relative spacing of the front of the head relative to the path of the saw blade.

Sixth, to form all elements other than the supporting bracket and centering pivot housing and clamp of rectangular material for maximum rigidity and maintenance of orientation.

In describing the invention reference will be had to the accompanying drawings, in which:

FIG. 1 is a side elevation of the invention and indicating the angular position for bevel sawing of a disc or the like.

FIG. 2 is a front elevation of the invention.

FIG. 3 is a side elevation of the supporting bracket with clamping means and the adapter bracket.

FIG. 4 is a front elevation of the clamping means and brackets with the supporting arm sectioned.

FIG. 5 is an enlarged sectional elevation through the centering pivot housing and showing the pivot.

3,131,735 Patented May 5,v 1964 FIG. 6 is an enlarged top plan View of a modication of the centering pivot arm, with the center-ing pivot arm oli-set for deep gaps between the front of the housing and the saw blade.

The invention consists of a supporting arm 10 which is preferably formed of rectangular tubing and which terminates at its inner end in a clamping element consisting of a disc ixed on each side of the arm as indicated at 11 and 12 and having an axial passage formed therethrough for the clamping bolt 13.

The supporting bracket includes a base 14 which is attachable to the mounting bracket 15 as indicated at 16, with the mounting bracket adapted to the speciiic make and model of band saw.

The supporting bracket is provided with a pair of spaced, fairly extended

ears

17 and 18 with the ear 18 having a passage formed therethrough and in which the clamping screw 13 is rotatable; the other ear having a hub 19 which has a threaded passage for the threaded end 20 of the clamping screw, While the other end of the clamping screw has a lever 21 fixed thereon, the Iit between the discs 11 and 12 and the

ears

17 and 18 being normally frictional and thus requiring very little movement of the clamping lever 21 for securely clamping the arm in any desired adjusted position. The arm 10 can be swung into a position parallel to the work-supporting table and then held in this position by actuating the clamping lever 21.

A sleeve 22 is slidable on the arm and is provided with a clamping screw 23 for securing the sleeve in adjusted position, and a second sleeve 23' is ixedly attached at right angles to one side Wall of the rst mentioned sleeve as indicated at 24, this second sleeve also being provided with a clamping screw 25. A drop arm 26 is slidable in this second sleeve and is secured in perpendicular adjustment by the clamping screw 25.

The drop arm 26 terminates at its lower end in a third sleeve which is positioned at right angles thereto and to the supporting arm, and is also provided with a clamping screw 27, this sleeve 28 being xed to the end of the drop arm as indicated at 29.

A centering pivot arm 30 is slidable in the third sleeve and releasably secured by the clamping screw 27, and the centering pivot housing 31 is xed to the terminal end of the centering pivot arm as indicated at 32. For deep gaps it may be necessary to provide the centering pivot arm with a right-angled extension 33, for minimum radii.

The centering pivot includes the housing 31 having an inturned flange 34 at its lower end, and a removable cap 35 at the upper end.

'Ihe centering pivot 36 is shown as conically formed and is limited as to projection by an annular collar 37 which froms a part of the centering pivot and normally seats on the ange 34 and is slidable in the housing. A Washer 38 is slidable in the housing with the shank 39 of the centering pivot 36 slidable therein, and a sleeve 40 provides a spacer between the washer and the head 35. A compression spring has its respective ends seated on the washer and on the annular shoulder 37. This arrangement provides for quick assembly, which consists in the depression of the sleeve 40 by the cap, followed by screwing the cap on the housing for placing the spring 41 under suitable tension for effective securing of the form or blank 42 on the table 43.

FIGURES 1 and 5 show the shank 39 of the centering pin 36, as extending upwardly through an opening provided in the cap 35 and provided with a head 44 that is normally spaced above the cap. If the blank 42 that is to be held against the table 43 is a harder wood so that the spring 41 will not force the center point 36 into it to the desired extent, the operator can hit the head 44 with his hand for moving the shank 39 downwardly and forcing the center point 36 farther into the blank. The centering pin 36 will now hold the blank 42 against the table 43 with sufcient force for preventing transverse movement of the blank with respect to the center point while permitting the operator to rotate the blank for causing the band saw to make a circular cut in it.

As will be noted by the dotted iigure indicated at 3l' and 36', by adjusting the supporting arm to a plane parallel with the bed or table 43 as indicated at 43', an exacting operation can be depended upon since al1 inembers are rigidly connected, none of the members being rotatable one relative to the other, with the exception of the centering pivot which rotates with the blank.

I claim:

l. A circle attachment for a band saw having an adjustable table swingable into different angular positions with respect to a horizontal plane, and a head, comprising:

(a) a support arm;

(b) means for pivotally mounting one end of said support arm on said head of the band saw, said means permitting said support arm to be swung into different angular positions about a horizontal axis and in a vertical plane and to be held in the desired angular position;

(c) clamping means for securing said support arm in the desired angular position;

(d a sleeve slidable along said support arm and being manually movable into a desired position on said arm, said sleeve having a second sleeve whose axis extends at right angles to the axis of the first-mentioned sleeve;

(e) a drop arm slidably mounted in said second sleeve and carrying a third sleeve at its lower end, the axis of said third sleeve extending at right angles to the axis of said drop arm and to the axis of said support arm;

(f) means for securing said drop arm in adjusted position in said second sleeve for positioning said third sleeve;

(g) a centering pivot arm slidably mounted in said third sleeve and having one end supporting a pivot housing that extends at right angles to the axis of the centering pivot arm; and

(h) a spring urged centering pivot mounted in said i housing and having a pivot point projecting from the lower end for centering and securing a blank to said table for cutting an arcuate member therefrom. 2. A structure as dencd in claim 1, and in which said 5 mounting means comprises (a) a base plate having spaced ears projecting at right angles to the base, and with the supporting arm having a friction disc fixed to each side wall and frictionally tting between said ears;

(b) a clamp bolt passing through one of said ears, the discs and the arm and being threaded into the other of said ears;

(c) said clamp bolt having a lever for manual operation and in combination providing said pivotal mounting and clamping means; and

(d) a mounting bracket having said base plate removably seeured thereto as adapted to the specific band saw to which it is to be attached;

(e) said adjustable table being tiltable into a desired angular position; and

(f) said support arm being swingable about its supporting means into an angular position Where the longitudinal axis 0f the supporting arm will parallel the plane of the inclined adjustable table.

3. The combination as set forth in claim l, and in which (a) said pivot housing having a guide opening in its top;

(b) said centering pivot having a shank slidably extending through the guide opening in the top of said pivot housing; and

(c) said shank having a head on its upper end that is normally spaced above the top of said housing;

(d) said head adapted to be manually hit for creating a temporary downward force on said shank for driving the pivot point of said centering pivot down into the blank on said table for holding the blank thereagainst While permitting the blank to be rotated while cutting the arcuate member therefrom.

References Cited in the file of this patent UNITED STATES PATENTS

Claims

1. A CIRCLE ATTACHMENT FOR A BAND SAW HAVING AN ADJUSTABLE TABLE SWINGABLE INTO DIFFERENT ANGULAR POSITIONS WITH RESPECT TO A HORIZONTAL PLANE, AND A HEAD, COMPRISING: (A) A SUPPORT ARM; (B) MEANS FOR PIVOTALLY MOUNTING ONE END OF SAID SUPPORT ARM ON SAID HEAD OF THE BAND SAW, SAID MEANS PERMITTING SAID SUPPORT ARM TO BE SWUNG INTO DIFFERENT ANGULAR POSITIONS ABOUT A HORIZONTAL AXIS AND IN A VERTICAL PLANE AND TO BE HELD IN THE DESIRED ANGULAR POSITION; (C) CLAMPING MEANS FOR SECURING SAID SUPPORT ARM IN THE DESIRED ANGULAR POSITION; (D) A SLEEVE SLIDABLE ALONG SAID SUPPORT ARM AND BEING MANUALLY MOVABLE INTO A DESIRED POSITION ON SAID ARM, SAID SLEEVE HAVING A SECOND SLEEVE WHOSE AXIS EXTENDS AT RIGHT ANGLES TO THE AXIS OF THE FIRST-MENTIONED SLEEVE; (E) A DROP ARM SLIDABLY MOUNTED IN SAID SECOND SLEEVE AND CARRYING A THIRD SLEEVE AT ITS LOWER END, THE AXIS OF SAID THIRD SLEEVE EXTENDING AT RIGHT ANGLES TO THE AXIS OF SAID DROP ARM AND TO THE AXIS OF SAID SUPPORT ARM; (F) MEANS FOR SECURING SAID DROP ARM IN ADJUSTED POSITION IN SAID SECOND SLEEVE FOR POSITIONING SAID THIRD SLEEVE; (G) A CENTERING PIVOT ARM SLIDABLY MOUNTED IN SAID THIRD SLEEVE AND HAVING ONE END SUPPORTING A PIVOT HOUSING THAT EXTENDS AT RIGHT ANGLES TO THE AXIS OF THE CENTERING PIVOT ARM; AND (H) A SPRING URGED CENTERING PIVOT MOUNTED IN SAID HOUSING AND HAVING A PIVOT POINT PROJECTING FROM THE LOWER END FOR CENTERING AND SECURING A BLANK TO SAID TABLE FOR CUTTING AN ARCUATE MEMBER THEREFROM.