Patent Publication Number: US-3877500-A

Title: Rotary tool guard

Description:
United States Patent 1 1 1111 3,877,500  
 Ulmer Apr. 15, 1975 ROTARY TOOL GUARD 955,482 4/1910 Stewart 144/251 A [76] Inventor: Jamie F. U lmer, Rt. 1, Hwy. 70, Mount Juhet Tenn- 3,568,567 3/1971 Seck 90/11 R x [22] Filed: July 13, 1973 Primary Examiner-Andrew R. Juhasz 21 A LN 378 987 1 pp 0 Assistant Examiner-W. D. Bray Attorney, Agent, or FirmHarrington A. Lackey [52] US. Cl 144/251 A; 83/544; 90/11 R [51] Int. Cl. B27g 19/00 [58] Field of Search 90/11 R, 12 R; 144/134 R, [57] ABSTRACT l44/134A,251R, 251A, 2518,252 R, 252 A l d d l l h A, 253 R; 83/544 545 546 397i, 478 rotary too guar an more partlcu ary a s aper guard, mcludrng a disc-shaped transparent guard [56] Reterences Cited member fixed to the vertical spindle above the rotary UNITED STATES. PATENTS tool, for rotary movement w1th the tool. 828,706 8/1906 Bohling et a1 144/251 A 4 Claims, 2 Drawing Figures ROTARY TOOL GUARD BACKGROUND or THE INVENTION This invention relates to a rotary tool guard, and more particularly to a shaper guard.  
  Heretofore, shaper guards have been of various designs, primarily ring-shaped, and mounted above the rotary shaper tool by a standard or bracket&#39;fixed to the shaper table at a laterally remote position from the shaper tool spindle. I  
  The prior art shaper guards, because of their stationary position and stationary mounting are oftentimes removed by the operator because the shaper guard, or its mounting bracket, gets in the operators way, or obscures the operators vision of his work. The removal of the shaper guard and its mounting bracket, of course, maximizes the danger of injury to the operator.  
  Such prior art shaper guards are clearly shown in US. Pat. No. 1,706,156 issued to Hall on Mar. 19, 1929, and US. Pat. No. 2,642,104issued to Brown on June l6, 1953.  
  The broad idea of the transparency of a shaper guard, as an optional feature, is disclosed in US. Pat. No. 2,895,518 of Rhett, issued July 21, 1959, in column 4, lines 44-50. However, the Rhett shaper guard is also supported in a fixed position relative to the spindle by a support spaced laterally of the spindle.  
 SUMMARY OF INVENTION It is therefore an object of this invention to provide a rotary tool guard, and more particularly a shaper guard, which has an annular transparent body, and which is adapted to be fixed to the spindle of a rotary tool. The transparent body permits continuous and clear visibility of the work beneath the guard, regardless of the position of the guard; while fixing the guard to the spindle discourages removal of the guard from the spindle, particularly while the spindle and guard are both rotating.  
  Another object of this invention is to provide a shaper guard which has no mounting portions or brackets projecting laterally beyond the periphery of the guard itself.  
  The rotary tool guard made in accordance with this invention includes a unitary disc-shaped guard member having a hole in the center thereof adapted to be fitted over the vertical spindle, and means holding the guard rigidly upon the spindle above the rotary tool for rotation with the tool. The guard member also includes a major annular body portion of transparent material, such as transparent acrylic plastic, and preferably surrounded by an annular peripheral rim of soft, resilient material, such as rubber or polyurethane.  
 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top perspective view of the guard made in accordance with this invention mounted upon the spindle of a shaper tool, with portions of the shaper table and fence shown fragmentarily;  
  FIG. 2 is an enlarged fragmentary section taken along the line 22 of FIG. 1.  
 DESCRIPTION OF THE PREFERRED EMBODIEMENT Referring now to the drawings in more detail, the table 11 and fence 12 of a conventional spindle shaper machine are disclosed fragmentarily.  
 Projecting upward through an opening 13 in the table shown, within the machine 10 and below the table 11. Fixed upon the spindle 14 is the shaper tool 15 having blades 16 of the desired configuration for forming or shaping a wooden piece or work fed over the top of the table for cutting engagement with the shaper blades 16. The fence 12, of course, is employed to guide the work as it is shaped. 1  
  The shaper blades 16 are fixed upon the lower portion of the upper section 18 of the spindle 14, the upper section 18 being that part of the spindle 14 which projectsabove the hole 13 in the table 11. The upper spindle section 18 is adapted to project above the shaper blades 16, and is also preferably threaded, as shown.  
  The rotary tool guard or shaper guard 20 is discshaped and provided with a hole 21 in the center thereof to fitsnugly over the upper spindle section 18. The hole 21 may be defined by an annular bearing sleeve or liner 22 forming the inner periphery of a bearing hub 23.  
  Surrounding the hub 23 and forming the major portion of the guard member 20 is an annular body portion 24 preferably of solid, transparent material, such as a transparent acrylic resin, for example Plexiglas.  
  A groove 25 is formed circumferentially around the periphery of the annular body portion 24 to receive the annular rib 26 of the annular rim 27 of the guard member 20. The annular rim 27 is made of a soft resilient material, such as rubber or polyurethane for protection of the operator against accidental contact with the periphery of the guard member while rapidly rotating with the spindle 14.  
  The bottom surface of the guard member 20 may be separated from the shaper tool 15 by a washer or spacer 28 around the spindle section 18. The spacer 28 also provides a surface against which the guard member 20 is forced and held in clamped position by the nut member 30. The nut member 30 threadedly engages the upper spindle section 18 and is tightened down upon the guard member 20 which is forced against the spacer 28. In this manner, the guard member 20 is held in fixed position relative to the spindle 14 and the shaper tool 15, so that the guard member 20, as well as the shaper tool 15, rotates as a unit with the spindle 14.  
  By fixing the shaper guard 20 to the spindle 14, the rapid rotation of the shaper guard 20 with the blades 16 discourages the operator from attempting to remove the guard member 20 from the spindle 14.  
  Since the guard member 20 rotates rapidly with the spindle 14, maximum visibility by the operator through the guard member 20 into the work engaging the shaper blades 16, is obtained by the incorporation of the large annular transparent body portion 24. Since the transparent body portion 24 is completely annular and of uniform radial dimensions, visibility through the guard member 20 is uniform and continuous regardless of the rotational position or rotational speed of the guard member 20.  
  Although a bearing hub 23 and sleeve 22 are disclosed, it is of course within the scope of this invention to provide a guard member 20 which is of uniformly solid, transparent material having a hole 21 therethrough for fitting over the spindle section 18. The absence or presence of the bearing elements 22 and 23 depends upon the structural nature of the transparent material 24 or the structural requirements of the member 20, vis-a-vis the degree of transparency desired. The annular rim 27 also may be an optional&#39;feature, but is preferred because of its additional safety characteristics in minimizing injury to the operatorof the shaper apparatus 10. a l  
  Furthermore, since the sole mounting means for the guard member 20 is the hole 21 fitted about the upper spindle section 18 and the nut 30 and spacer-28, there are no laterally projecting mounting means or brackets which will be in the way of the operation of the rotary tool upon the work. Also, because of the maximum vision provided by the transparent annular body portion 24, there is less likelihood of the tool operator being sufficiently annoyed or discommoded even to desire to remove the guard member from the spindle member 14.  
 What is claimed is:  
  1. A guard for a rotary tool apparatus having a platform, a vertical spindle projecting above said platform and rotatably driven about its vertical axis, and a rotary tool fixed to the portion of the spindle adjacent and above said platform for operating upon work upon said 4. said rotary tool, b. means supporting said guard member coaxially upon said spindle above said rotary&#39; tool, and c. said guard member comprising an annular body portion of solid, circumferentially uninterrupted, transparentmaterial, to permit continuous vision through said annular body portion, even while said guard member is rotating, said guard member further being provided with a rim of soft resilient material fixed to and surrounding the periphery of said transparent annular body portion.  
  2. The invention according to claim 1 in which the transparent material of said annular body portion is rigid.  
  3. The invention according to claim 2 in which said means supporting said guard member comprises bearing means in the center of and fixed to said annular body portion for supporting said guard member coaxially upon said spindle.  
  4. The invention according to claim 3 in which said transparent annular body portion constitutes the major portion of said guard member and lies substantially in a horizontal plane with said bearing means and said annular rim, said rigid transparent material being structurally self-supporting and integrally connecting said bearing means and said annular rim.