US 3005477 A
Description (OCR text may contain errors)
Oct. 24, 1961 T. SHERWEN 3,
ROTARY TOOL WOOD WORKING MACHINES Filed Dec. 3, 1958 4 Sheets-Sheet 1 Oct. 24, 1961 T. SHERWEN ROTARY TOOL WOOD WORKING MACHINES 4 Sheets-Sheet 2 Filed Dec. 3, 1958 Oct. 24, 1961 T. SHERWEN ROTARY TOOL WOOD WORKING MACHINES 4 Sheets-Sheet 3 Filed Dec. 5, 1958 Oct. 24, 1961 T. SHERWEN ROTARY TOOL WOOD WORKING MACHINES 4 Sheets-Sheet 4 Filed Dec. 3, 1958 United States 3,005,477 ROTARY TOOL WOQD WORKING MACHINES Theo Sherwen, Minchinhampton, England, assignor to Horstmann & Sherwen Limited, Leafield, Corsham, Wiltshire, England, a British company Filed Dec. 3, 1958, Ser. No. 777,892 Claims priority, application Great Britain Dec. 23, B 57 2 Claims. (Cl. 14347) This invention relates to Wood Working machines of the kind employing a rotary tool such as a circular saw, and is concerned with the provision of a generally improved machine of this nature which is both safe and easy to operate and is, at the same time, capable of performing a wide range of extremely accurate work.
The term wood as used throughout the specification is intended to include any other material which can be similarly worked.
According to the invention there is provided a wood working machine of the kind-specified having a worktable with an elongated working slot therein, through which a rotary tool can be projected from underneath the table to operate on a workpiece located on the table top, and having a slideway disposed below the table and lengthwise of the table slot for carrying the said rotary tool, said slideway being adapted for adjustment about an axis parallel to the table top in order to vary the working angle of said tool in relation to the table top.
In order that the invention may be clearly understood and readily carried into effect, an embodiment thereof will now be described in detail with reference to the accompanying drawings in which:
FIGURE 1 is an end elevational view of a wood working machine of the invention, the view being partially broken away and sectioned at one corner,
FIGURE 2 is a plan view according to FIGURE 1,
FIGURE 3 is a cross-sectional view of the machine shown in FIGURES l and 2 and is taken on the line III-III of FIGURE 4,
FIGURE 4 is a longitudinal part-section taken on the line IV-IV of FIGURE 3,
FIGURE 5 (Sheet 1) is a sectional detail view showing one form of mounting bracket for a work-locating fence, and
FIGURE 6 is a further detail view taken in the direction of the arrow VI in FIGURE 4.
Referring now to the drawings, the wood working machine illustrated is intended mainly for use as a circular saw and is provided with a main framework in the form of a U-shaped open-ended cradle with a flattened bottom or base 1, which is intended to rest on a work bench, and upstanding arms 2 which support a work table 3. The arms 2 of the main framework may be constituted by two substantially identical castings, these castings being secured by bolts 4 to opposite ends of the base 1 which is conveniently constituted in box-like section from two channel members one of which is inverted over the other as can be seen in FIGURE- 1. The base 1 is centrally apertured at 5 to receive a single fastening bolt or the like which will be passed through the work bench. This mode of fastening enables the entire machine to be swung around an axis perpendicular to the plane of the work bench so that a long length of timber, for example, can be most conveniently located on the work table when space in the work room is limited.
Encircling the upper ends of the main frame arms 2 is a metal band 6 the upper edge of which serves to support the work table 3. This work table 3 is of generally flat rectangular form, as can be seen in FIGURE 2, and is conveniently divided longitudinally into two coplanar parts which are slightly spaced, in the mounted Patented Oct. 24, 1961 position to provide a narrow working slot or opening 7 therebetween which extends over the full length of the table between the main frame arms. The two co-planar parts of the table 3 are conveniently secured to inturned flanges 2a at the tops of the main frame arms 2 by means of bolts 8 which extend through elongated slots 2b in the flanges 2a for engagement with co-operating nuts 20 one of which can be seen in FIGURE 4. The bolts 8 are conveniently projection welded to the under sides of the table parts and these table parts are further located on the main frame by the engagement of dependent studs on the table in locating holes 2d provided in the arm lips 2:1. It is to be noted from FIGURE 2 that a series of three such locating holes 2d are provided beneath each end of one table part, the purpose being to enable this latter part to be adjusted away from the other table part for the purpose of enlarging the working slot 7 in cases where such enlargement is made necessary by the type of cutting tool employed. Each table part is also preferably provided with a strengthening strip 9, these strips being secured beneath the respective table parts along the edges thereof which bound the working slot 7.
Mounted beneath the work table between the arms 2 of the U-frame is an oblong sub-frame which can be seen most clearly in FIGURE 4 and which provides a slideway mounting for a circular saw blade 10 as will later become clear. The sub-frame consists of an upper rod 11 and a lower parallel tube member 12 which are joined together at their ends by the side arms 13- to complete the sub-frame. This jointing is effected by pinning the ends of rod 11 in apertured bosses 13a formed at one end of each arm and by extending the ends of tube 12 through similar bosses 13b provided on the other arm ends. The rod 11 and tube member 12 are disposed parallel to the plane of the work table 3 and are of such length that the side arms 13 of the sub-frame are located one adjacent the inside surface of each of the two arms 2 of the main frame.
The sub-frame is supported by means of arcuate projections 14 which extend outwardly from the sub-frame side arms 13 and engage in arcuate face grooves 15 (seen particularly in FIGURES 3 and 6) on the inside of the main frame arms 2. This enables the sub-frame to be angularly adjusted in relation to the plane of the work table about a longitudinal axis which is positioned in the centre of, both horizontally and vertically, and parallel to the work table slot 7. To enable the sub-frame to be clamped in various positions of angular adjustment, a long bolt 16 is passed through the lower tubular member 12 of the sub-frame and through arcuate slots 17 in the respective main frame arms 2. This bolt 16 has a head 18 at one end which can be brought to bear against the outside surface of the adjoining main frame arm, and which is prevented from rotating by means of a tab washer. At the other end the bolt engages a handle-operated nut 19 which can be brought to bear against the outside surface of the other main frame arm. Thus, by tightening down the nut 19, the sub-frame can be securely clamped in any position of angular adjustment to which it may be brought. Locating bushes 20 may be provided between the bolt and the ends of tube 12 as required.
The location of the longitudinal adjustment axis of the sub-frame is of some importance in enabling a minimum width of working slots 7 for the saw blade to be used as will be later explained, and, this in turn makes for cleaner and better sawing results.
Arranged to ride along the upper rod 11 and lower tube member 12 of the sub-frame is a carriage 21 which is conveniently constituted by a four-sided frame-like casting having an open centre. The carriage 21 is provided with a transverse bored boss 22 at each upper corner, these bosses being slidably engaged over the subframe rod 11. At the lower end of one side memher. of, the carriage there are provided upper and lower trunnionbearings 23, 24 these bearings being arranged respectively to engage trunnions 2.5 which project from opposite sides of a collar 26 slidably mounted on the sub-frame tube member 12. This manner of attaching the lower end of the carriage to the tube member 12 of the: sub-frame ensures reasonable manufacturing tolerances;
Two posts 27 and 28 are mounted on the carriage 21 in spaced relationship and parallel to the carriage side members so as to extend across the carriage centre opening approximately perpendicular to the sub-frame rod-l1 and tube member 12 and project below the carriage. These posts have narrowed upper ends 27a, 28a which are located respectively in upper bearings 29a, 29b and lower bearings 30a, 301; on the carriage, the post 27 at least being freely rotatable in its bearings but being anchored against axial movement in relation to the carriage. The upper end of post 27 has screw threads 27b and the lower end is provide withan operating handle 31 whereby this post can be rotated in its carriage bearings 29a, 30a for a purpose which will later become clear.
An electric saw driving motor 32 is carried by the twoposts 27 and 28 so as to project on one side of the sub-frame from what may be termed, for convenience of description, the rear face of the carriage 21 (.see- FIGURES 2 and 3). For the purpose of attaching the motor to the posts, a casting 33 is bolted to the front face of the motor and provides a casing for gearing 34 whereby a drive is transmitted from a motor spindle 35 to a saw blade spindle 36. This saw blade spindle 3'6 is arranged to project through a ball bearing 37 seated in an opening in the front motor casting 33 and, at the rear end 36a is supported by a needle roller bearing on the main motor casing. The saw blade spindie 36 is arranged to project between the two posts 27 and 28 and through the upper and lower sub-frame members 11 and 12 to carry the saw blade 10 on the side of the sub-frame remote from the motor and with part of the blade periphery projecting through the working slot 7 in the table. Upper and lower apertured projecting parts 39a, 40a and 39b, 40b (FIGURE 4) on the front motor casing 33 respectively provide aligned bearfor posts 27 and 28. The bearing 39a is internally screw-threaded and co-operates with the screw-threads 27b on the upper end of post 27 so that, by rotating the post 27' by means of the handle 31, the motor and attached saw blade can be raised and lowered on the carriage with reference to the work table.
Extending forwardly from the projecting part 4% of front motor casing 33 is a bracket arm at having a downturned extremity to which the lower end of a riving knife 42 is secured by means of a bolt 43. This riving knife is arranged to follow the trailing periphery of the saw blade 19 through approximately 180 so that the upper end of the knife projects with the saw blade through the working slot '7. About midway along its length, the riving knife 42 is also secured by a bolt 44 to a further bracket 45 which extends laterally and forwardly from the front motor casing 33.
For the purpose of traversing the carriage 21, a tubular rod -46 extends from the carriage 21 approximately parallel to the rod 11 and tube member 12 of the subframe and projects, at the outer end, through an arouate slot 47 (see FIGURE 1) in the adjoining main frame arm. At the inner end this rod 46' is anchored to the carriage 21 by engagement within a laterally projecting boss 48 on the carriage. At its outer end, the traversin rod 4a is provided with a handle 49 which can be grasped by the saw operator and pulled outwardly of the frame to cause the carriage 21 to move along the sub-frame, and thus also the saw blade to traverse along the working slot 7 from one end of the work table to the other. This operating handle 49 may incorporate a switch 50 for the saw blade motor, the leads for which can be taken down the inside of the tubular traversing rod 46. It will. be observed that the operating handle 49 and the hand-operable clamping nut 1.9 of the sub-frame projectthrough the same main frame arm so as to be readily accessible to an operator of the machine without having to move from one end of the machine to the other. A. pointer 51 is secured to the sub-frame opposite the arcu-ate slot 47 and is arranged to work against a scale 52; provided along; the edge of this slot to indicate the angle of tilt at which the sub-frame, and thus also the saw blade, is set.
A shield member, not shown, will normally be provided over the front of the sub-frame, i.e. onthe side thereof remote from the motor 62, this shield beingattached to the end arms of the sub-frame and serving to cover the exposed face of the blade part which lies beneath the Work table. A further shield may also. be provided on the opposite side of the saw blade beneath the work table between the motor and. carrying posts. With these two shields, the possibility of an operator accidentally touching theblade beneath the table is virtually eliminated.
The part of the blade which projects above the work table top will normally be fully protected by a saw guard which forms no part of the present invention and. which may be mounted on the upper end of the riving knife 42.
To enable a sawing fence to be readily located on or removed from the work table, a sawing fence bracket 53 (see FIG. 5) is arranged for rapid attachment to or detachment from the main frame arm 2 through which the traversing rod 46 projects. To this end, the bracket 53, which is intended to carry a cross-cutting fence, is arranged to straddle a screw 54, which projectsv from the main fiarne arm, andis clamped thereon bymeans of a screw collar 55 having a turning handle 56 at the outer end. To locate the bracket 53 against tilting. on the main frame arm 2, studs 57 positioned at the three corners of a triangle project from the frame arm and band 6 to enter pro-formed recesses in face SS'aof bracket 5-3. To provide for rapid to and fro adjustmentof the cross-cutting fence of the work table, the bracket 53 is conveniently provided with a hollow boss 58 at the upper end in which an arm 59 for carryingthe fence is slidably mounted. To control sliding movement of the arm 59- inboss 58, the boss 58 is conveniently split and the parts connected by a hand-operable clamping screw 60. In cases where a ripping fence is to be employed, a fourth projecting stud 57a (FIGURE 1) may be provided on the frame arm to provide an additional laterally ofiset locating point for the fence bracket.
To enable the machine to be adapted for spindle. moulding, a hole 61' (FIGURE 2) is provided in one of the table parts to one side of the working slot 7 in such'a position that the spindle of the saw motor will be positioned approximately centrally the'rebeneath if the sub-frame is swung into substantially parallel relationship with the work table. For this purpose the. traversing rod 46 is removed and the bolt 16 through the lower tubular member 12 of the sub frame is disengaged from, the arcuate slots 17 in the main frame arms and reengaged through alternative holes 62 (FIGURE -l) in the main frame arms. Before adjusting the machine for. spindle moulding, the saw blade 10 and riv-ing. knife 42 will, of course, also be removed and a modified-fence,- which forms no part of the present invention may also be employed if desired; When the sub-frame is in parallel relationship with the working table, the end. of bracket arm 41' onthe front motor casing, which normally sup ports the bottom of the riving knife 22, will bear against the under surface of the table.
For performing angular cuts, the blade 22 can be tilted in the slot through an appreciable angle, one such limiting position for this an le of tilt being indicated in chain-dotted lines in FIGURE 3 of the drawings.
By making one half of the work table adjustable it also becomes possible to employ a routing cutter with this machine. For this purpose the working slot is widened by moving back one half of the table to receive the routing cutter which will project through the widened working slot.
1. A woodworking machine comprising a main frame having opposed arms upstanding from a turntable base adapted for releasable clamping against a support surface on a pivot axis normal to said surf-ace, a slotted work table carried by said arms, a slideway also carried by said arms beneath and substantially parallel to the plane of said work table, carriage means on said slideway for supporting a rotary tool with a working part thereof projecting through said slot, driving means on said carriage for rotating said tool, said slideway being constituted by an oblong sub-frame having upper and lower frame members extending parallel to each other and to the plane of the work table and side armswhich extend transversely to the aforesaid upper and lower members, said side arms having arcuate outer projections thereon and the main frame arms having arcuate inner face grooves in which said projections are slidably engaged to support said sub-frame for angular adjustment about a longitudinal axis which is centered both horizontally and vertically in said table slot, said lower sub-frame member being hollow and a clamping bolt extending therethrough and, at opposite ends, through registering 6 arcuate slots in the respective main frame arms, said bolt being operable from one end of the machine to clamp said sub-frame in a desired position of angular adjustment.
2. A woodworking machine as claimed in claim 1 further including a hollow traversing rod extending from said carriage through a further arcuate slot in the main frame arm at the end of the machine at which said clamping bolt is operable, said traversing rod being longitudinally displaceable by an operator to traverse the carriage, an operating handle at the outer end of said rod, and an electric switch in said handle and electric current leads housed within the said hollow traversing rod and connecting said switch with an electric tool driving motor on said carriage.
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