BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the preferred embodiment thereof which is illustrated in the appended drawings, which drawings are incorporated as a part hereof.
It is to be noted however, that the appended drawings illustrate only a typical embodiment of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
In the Drawings:
FIG. 1 is a plan view of a machine tool holder, such as a boring bar, having a coolant fluid supply passage therein according to the principles of the present invention, and representing the preferred embodiment of the present invention;
FIG. 2 is a longitudinal sectional view of the machine tool holder of FIG. 1, showing a swivel fitting for supply of coolant fluid, showing the coolant supply passage of the cutter support head and further showing a cutter retaining clamp and clamp retainer having a coolant fluid distribution passage directing a jet of coolant fluid to the cutting interface of a cutter insert;
FIG. 3 is a partial exploded isometric illustration showing the cutter support head portion of the machine tool holder of FIGS. 1 and 2, showing the relationship of the various components of the tool holder, coolant distributing clamp and cutter insert;
FIG. 4 is a sectional view taken along line 4-4 of FIG. 1, and showing an internal coolant flow passage that is cooperatively defined by a cutter retaining clamp and a clamp retaining fastener member and showing seals for sealing of the coolant fluid flow and distribution passages of the clamp retaining fastener member and cutter insert retaining clamp;
FIG. 4A is a diagrammatic illustration of the clamping and clamp and cutter insert positioning forces that are achieved upon tightening of the clamp retaining fastener member;
FIG. 5 is an exploded isometric illustration of the cutter retaining clamp and a clamp retaining fastener member and coolant fluid seals of FIG. 4;
FIG. 6 is a plan view of the integral shank and cutter insert support head structure of a machine tool holder representing an alternative embodiment of the present invention wherein a coolant fluid supply passage extends longitudinally through the shank or bar of the machine tool and supplies coolant fluid to fluid distribution and chip removal passages in the cutter support head portion of the tool;
FIG. 7 is a longitudinal sectional view of the integral shank and head structure of the machine tool holder taken along line 7-7 of FIG. 6 and showing coolant fluid supply and distribution flow passages and further showing cutter insert positioning with respect to the cutter support head portion of the tool;
FIG. 8 is an exploded isometric illustration of view of the cutter support head portion of the tool the machine tool holder of FIGS. 6 and 7, showing cutter insert positioning with respect to a cutter support seat and cutter support and showing positioning of cooling and chip removal jets with respect to the structure of the cutter insert support head;
FIG. 9 is an exploded isometric illustration of the coolant fluid emitting clamp member, the clamp retainer member and the cutter insert and cutter insert support member of the machine tool holder embodiment of FIGS. 6-8;
FIG. 10 is an exploded isometric illustration of the cutter support and coolant fluid distribution head portion of the machine tool of FIGS. 6-9;
FIG. 11 is a plan view showing the machine tool holder of FIGS. 6-10, with the tool holder shank being of rectangular cross-sectional configuration and the coolant fluid supply being directly connected to the cutter support head;
FIG. 12 is a longitudinal sectional view taken along line 12-12 of FIG. 11;
FIG. 13 is a plan view of a machine tool holder representing another embodiment of the present invention which is adapted for threading and grooving operations and which defines a cutter pocket for edgewise support of a cutter insert and which also includes a coolant fluid supply and distribution according to the principles of the present invention;
FIG. 14 is a longitudinal sectional view taken along line 14-14 of FIG. 13;
FIG. 15 is an exploded isometric illustration of the cutter support and coolant fluid distribution head portion of the machine tool holder of FIGS. 13 and 14;
FIG. 16 is an exploded isometric illustration showing the cutter retaining clamp and clamp retainer screw member of FIGS. 13 and 14;
FIG. 17 is a plan view showing a machine tool holder for threading and notching or grooving operations and having a coolant fluid distribution system according to the teachings of the present invention;
FIG. 18 is a longitudinal sectional view taken along line 18-18 of the machine tool holder of FIG. 1;
FIG. 19 is an exploded isometric illustration of the cutter support head portion of the machine tool holder of FIGS. 17 and 18;
FIG. 20 is an exploded isometric illustration of a cutter insert tool holder with the head portion of the tool being substantially identical to the head structure of FIGS. 17-19 and with the shank of the tool holder being of generally octagonal cross-sectional configuration rather than rectangular cross-sectional configuration;
FIG. 21 is a plan view taken of the machine tool holder of FIG. 20 and having a length depending on the length of the workpiece being machined;
FIG. 22 is a longitudinal sectional view taken along line 22-22 of FIG. 21;
FIG. 23 is an exploded isometric illustration showing the cutter insert retaining clamp and clamp retaining screw of FIGS. 17-22;
FIG. 24 is another exploded isometric illustration showing the cutter insert retaining clamp and clamp retaining screw of FIGS. 17-22 showing different cutter insert orientation as compared with the illustration of FIG. 23;
FIG. 25 is an isometric illustration of a boring bar assembly showing a tool holder with a boring bar in assembly therewith and having a sealing mechanism minimizing the potential for leakage of coolant fluid along the exterior flats of the boring bar;
FIG. 26 is a plan view of the boring bar assembly of FIG. 25;
FIG. 27 is a longitudinal sectional view taken along line 27-27 of FIG. 26;
FIG. 28 is a transverse sectional view taken along line 28-28 of FIG. 27;
FIG. 29 is an elevational view of a coolant seal support member of the boring bar assembly of FIGS. 25-27;
FIG. 30 is a transverse sectional view taken along line 30-30 of FIG. 29;
FIG. 31 is an elevational view of a coolant seal retainer member of the boring bar assembly of FIGS. 25-27; and
FIG. 32 is a sectional view taken along line 32-32 of FIG. 31.
FIG. 33 is another isometric illustration showing a boring bar and tool holder assembly similar to that of FIG. 25;
FIG. 34 is an end view of the reducer bushing of the boring bar assembly of FIG. 33;
FIG. 35 is a longitudinal sectional view taken along line 35-35 of FIG. 34;
FIG. 36 is a plan view showing the boring bar and tool holder assembly of FIG. 33;
FIG. 37 is a longitudinal sectional view taken along line 37-37 of FIG. 36;
FIG. 37A is an enlarged fragmentary sectional view showing the encircled region of FIG. 37; and
FIG. 38 is a transverse sectional view taken along line 38-38 of FIG. 37.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
For purposes of simplicity, the present invention is discussed herein particularly with respect to its form as a boring bar for cutting or boring operations on the interior of a work-piece being rotated by a metal working machine. However, it is to be understood that the present invention has application to a wide range of machine tool holders for external as well as internal machining operations; thus this specification is to be intended as descriptive of a wide range of cutter support machine tools and is not as intended as restricting the spirit and scope of the invention to boring bars or any other type of cutter supporting machine tools.
Referring now to the drawings and first to FIGS. 1-3 a coolant fluid supplying machine tool or cutter insert holder, such as a boring bar, is shown generally at 10, having an elongate tool shank 12 with cutter insert support head 14 at one end thereof and representing a preferred embodiment of the present invention. The cutter insert holder of FIGS. 1-3 is referred to as a JETSTREAM™ SCREW-LOCK™ (trademarks of Dorian Tool International) positive style square or rectangular shank tool holder The cutter insert support head 14 defines a coolant fluid supply passage 16 which in the embodiment of FIGS. 1 and 2 is internally threaded at 18 and threadedly receives a coolant supply fitting 20 such as the 90° swivel fitting that is shown in FIG. 2. The coolant supply fitting 20 is provided with a connector 22 adapting the fitting for connection with the corresponding quick-disconnect connector of a coolant supply hose (not shown).
The cutter insert support head 14 of the machine tool holder 10 defines a cutter insert seat 24 which provides stable support for a cutter insert member 26 which establishes a cutting interface with a workpiece being moved rotationally or linearly relative thereto depending upon the character of machining that is involved. The cutter insert member 26 is composed of hardened metal and defines a proper cutting edge rake angle for efficient machining of the workpiece. When the cutter insert member 26 becomes worn to the point that the efficiency of metal cutting becomes degraded the cutter insert member will be removed and replaced with a new cutter insert member.
Typically the cutter insert member 26 is provided with a central opening within which a retainer member such as a set screw is received and defines an internal shoulder or tapered surface that is engaged by a corresponding retainer portion of the set screw, thus positively securing the cutter insert member in immovable relation with respect to the cutter insert seat 24. The cutter insert seat is further defined by seat shoulders 28 and 30 of the head portion 14 which also function to stabilize the cutter insert member with respect to the head portion of the tool. The seat shoulders 28 and 30 may be slightly tapered or inclined at corresponding angles as compared with edge portion of the cutter insert member and the intersection of the shoulder surfaces is relieved as shown at 31 thus permitting the cutter insert member 26 to establish tight motion preventing engagement with the seat shoulders. This feature permits the cutter insert member to be firmly and immovably seated in the head portion of the tool and capable of withstanding extremely heavy cutting loads.
A clamp and coolant distribution member 32, best shown in FIGS. 3-5, is mounted to the head portion 14 and defines an insert retainer projection 34 that extends downwardly into a circular opening 36 of the cutter insert member 26. The clamp and coolant distribution member 32 defines a generally vertical passage 38 through which extends the threaded shank 40 of a clamp retainer screw 42. The threaded shank 40 is received by an internally threaded passage 44 of the head 14 and defines a central flow passage 46 through which coolant fluid flows from coolant fluid supply passage 16. The shank 40 of the clamp retainer screw 42 also defines a transverse flow passage 48 which intersects the central flow passage 46 also intersects a circular external groove 47 and provides for communication of the coolant medium with the generally vertical passage 38. Generally planar surfaces 50 and 52 and defined by the clamp member 32 for movement limiting engagement by the head portion 54 of the clamp retainer screw and for engagement by an annular seal member. A circular seal recess 56 is formed in the upper portion of the clamp member 32 and contains an annular, typically O-ring type resilient sealing member 58. The head portion 54 of the retainer screw 42 is sufficiently large to overlie the seal recess 56, to retain the resilient seal member 58 within the seal recess and to engage the upper surface 50 of the clamp member 32. The seal recess 56 is of such dimension, relative to the dimension of the seal member 58 that the seal member is maintained under sufficient compression to establish a positive seal between the clamp member and the head portion 54 of the retainer screw. If desired, a circular washer 59 may be interposed between the head of the retainer screw and the annular seal member 58.
As the retainer screw is tightened, it serves to cause compression of a lower annular typically O-ring type resilient seal 60 that is positioned around the shank of the retainer screw, thus establishing a seal between the clamp member and the shank 40 of the retainer screw to prevent leakage of the coolant fluid from the passage 38. The clamp and coolant distribution member 32 defines one or more coolant distribution passages 62 that intersect the generally vertical passage 38 and terminate at a coolant jet opening 64. The coolant jet opening or openings 64 is located in overlying relation with the upper portion of the metal cutting insert 26 and directs one or more jets of coolant fluid at the cutting interface of the metal cutting insert with a moving workpiece, thus efficiently cooling the cutting interface and significantly enhancing the service life of the metal cutting insert.
The clamp and coolant distribution member 32 also defines a depending projection 66 that is located at the rear portion of the clamp member and defines an angulated cam surface 68. When the clamp member 32 is tightened by forcible rotation of the retainer screw 42 the depending projection will enter a clamp recess 70 and will establish camming engagement with a corresponding angulated cam surface 72. As the angulated cam surfaces 68 and 72 interact during tightening of the clamp retainer screw 42 the clamp and coolant distribution member 32 is moved downwardly and rearwardly as shown by the clamping force distribution diagram of FIG. 4A. The downward and rearward force vectors evident from FIG. 4A cause the insert retainer projection 34 to apply downward and rearward clamping force to the metal cutting insert 26 thus ensuring that the metal cutting insert is retained in properly seated and supported immovable relation within the cutter insert seat 24. The rear portion of the clamp and coolant distribution member 32 also defines an orienting recess 74 within which is received an orienting pin 76 that is seated within a pin receptacle of the cutter insert support head 14. The orienting pin 76 is fitted tightly within the orienting recess 74 and serves to restrain the clamp and coolant distribution member 32 against potential rotation from its insert clamping position due to the forces of metal cutting operations. The combined effects of the clamp member 32, the angulated cam surfaces 68 and 72 and the orienting pin 76 cause the metal cutting insert to be positively locked within its seat and prevent any movement, vibration or chattering of the insert during the machining process.
As disclosed in FIGS. 6-12, an alternative embodiment of the present invention is referred to as a JETSTREAM™, LAY-DOWN™ style threading bar, shown generally at 80, having a threading insert clamping mechanism that also provides for coolant and chip removal flow through the clamping mechanism to provide jets of coolant fluid that are precisely directed to the threading interface and chip accumulation region of the threading tool. As shown in FIGS. 6 and 7, the threading bar 80 has an elongate shank 82 which is shown with an intermediate break since the shank can be of any desired length that is suitable for the threading operation that is to be conducted. A coolant supply passage 84 extends longitudinally through the shank 82 and a suitable coolant supply fitting, such as the swivel fitting 86, is threaded into an internally threaded portion 88 of the coolant supply passage. A coolant supply hose, not shown, is connected with the swivel fitting, typically by means of a quick-disconnect connector, to conduct coolant fluid from the coolant pump of the machining system. The threading bar 80 is typically of octagonal external configuration though it may have any other suitable configuration as well. A cutter support head 90 is integral with the elongate shank 82 and is provided with an internal coolant fluid distribution passage 92 that is typically defined by a drilled bore which intersects the coolant supply passage 84. A chip flush nozzle 94 is threaded into an internally threaded outer portion of the coolant fluid distribution passage 92. The chip flush nozzle defines an orifice from which a flushing jet of coolant fluid as a flushing medium is emitted, the jet being oriented to the machining region at which metal chips or cuttings are likely to undesirably accumulate during the threading or machining process. The flushing jet of coolant fluid is of proper dimension and force to dislodge accumulated metal chips or cuttings and to flush them away from the machining interface. When different machining operations, such as heavy cuts or light cuts are being accomplished, it may be desirable to unthread the chip flush nozzle from its threaded receptacle and replace it will a chip flush nozzle having an orifice of different dimension.
The cutter support head 90 defines a cutter insert seat recess 96, which in the case of threading bars is of generally triangular configuration and defines a seat surface 98. Seat shoulders 97 and 99 also define portions of the cutter insert seat recess and establish orientation and support for a threading or other metal cutting insert. An internally threaded hole 100 is also defined by the cutter support head 90 and receives a set screw or other suitable retainer member 101 which is employed to secure a cutter seat member 102 in fixed relation with the seat surface 98. A threading or thread cutting insert 104 or other suitable machining insert is positioned on the cutter seat member 102 and is clamped in place by a clamp member 106. The thread cutting insert 104 defines a thread cutting portion 106 having a thread cutting point 108 and having a desire rake angle for the optimum cutting of internal or external threads in a rotating workpiece. The thread cutting insert 104 defines a generally circular opening 110 within which is received a depending locking projection 112 that is integral with and extends downwardly from the clamp and coolant fluid distribution member 106. The depending locking projection 112 may be of tapered configuration as shown particularly in FIGS. 8 and 9 and may fit within a correspondingly tapered opening of the threading insert member thereby ensuring that the threading insert is positively locket at its optimum thread cutting position with respect to the head portion 90 of the threading bar. The geometry of the threading insert recess 96 and the geometry of the seat member 102 and the interfitting relation of the depending locking projection 112 within the insert opening 110 function in concert to prevent rotation of the threading insert relative to the seat recess and to prevent vibration or chattering of the threading insert as a threading operation is being accomplished. Stabilization and orientation of the seat member 102 and threading insert 104 is also enhanced by the seat recess shoulders 97 and 99.
The clamp and coolant fluid distribution member 106 is of substantially the same construction and purpose as compared with the clamp and coolant fluid distribution member 32 of FIGS. 1-5. The clamp member is forcibly retained to the head portion 90 of the threading bar 80 by a clamp retainer screw 114 having an externally threaded screw shank 116 that extends through a passage 118 of the clamp member and is received in threaded engagement within a threaded bore 120 that is defined within the cutter support head 90. The clamp retainer screw 114 has an internal longitudinal passage such as is shown and described at 46 in FIG. 4 and a transverse passage and circumferential groove as shown at 47 and 48 in FIGS. 4 and 5. The clamp and coolant fluid distribution member 106 further defines an internal coolant distribution passage, such as is shown at 62 in FIG. 4, which terminates at a coolant jet opening 122 that is of a suitable dimension and orientation to project a jet of coolant fluid directly onto the metal cutting interface of the threading insert 104 with a rotating workpiece. If a smaller or larger jet opening is needed, it is a simple process to remove the clamp member 106 and replace it with a jet opening of desired dimension and orientation. Also, if desired the clamp member may be provided with a removeable and replaceable jet nozzle that is threaded into an internally threaded outlet portion of the coolant distribution passage, thus providing a simple and efficient means for changing the coolant jet application to the cutting or threading interface of the threading or cutting insert without necessitating removal of the clamp member.
The downward and rearward force vector application exemplified by the force vector diagram of FIG. 4A is achieved by the clamp and clamp retainer screw members in the manner discussed above. The clamp and coolant fluid distribution member 106, as shown in the exploded view of FIG. 9 and in FIGS. 10-12, is provided with a depending locking projection 124 having a tapered cam surface 126. As the clamp member is forced downwardly by tightening its clamp retainer screw 114 the tapered cam surface 126 reacts with a correspondingly tapered surface 128, best shown in FIG. 12, and applies downward and rearward forces to the clamp member. These downward and rearward forces are represented by the force vectors shown in the vector diagram of FIG. 4A and are transferred via the clamp member 106 to the threading or other metal cutting insert 104. In this manner the threading or other metal cutting insert 104 is positively secured in firmly seated relation within the seat 96 and in supported relation with seat shoulder surfaces 97 and 99. The clamp member is further oriented and stabilized by means of a clamp orienting pin 129.
With reference to FIG. 10, a threading bar embodying the principles of the present invention and shown generally at 130 may also have a square or rectangular shank 82a which may have an internal longitudinal coolant supply passage and coolant supply fitting similar to that shown at 84 in FIG. 7. However, as shown in FIGS. 10 and 12, a coolant fluid supply fitting 131, such as a swivel fitting, is threaded into an internally threaded outer portion 132 of a coolant fluid supply passage 134 that is drilled or otherwise formed only in the cutter support head portion 90a. The coolant fluid supply passage 134 is in fluid communication with the internally threaded bore 120 into which the threaded shank portion 116 of the clamp retainer screw 114 is received. The threading insert clamp and clamp retainer screw are of essentially identical configuration and function as described above in connection with FIGS. 1-5. Though the coolant fluid flow passage through the clamp retainer screw is shown to be defined by an internal longitudinal bore which intersects a transverse passage, it should be borne in mind that this particular clamp retainer screw construction is not intended to limit the spirit and scope of the present invention in any manner whatever. If desired, the threaded shank of the clamp retainer screw may define an external groove or the threaded bore 120 may define an internal groove which functions as a coolant flow passage. It is only necessary that the clamp and coolant distribution member 106 be sealed to the threading insert support head 90a of the threading bar or other machine tool 130 and that the retainer screw be sealed to the clamp and coolant distribution member to prevent leakage of the coolant fluid at these mechanical joints. The elongate configuration of the threading insert clamp member 106 provides for location of the coolant fluid jet orifice or nozzle 122 in overlying relation with the threading or metal cutting insert 104 and position for directing a jet of coolant fluid directly onto the cutting interface of the threading or metal cutting insert with a rotating or otherwise moving workpiece. This feature causes efficient cooling of the threading or other metal cutting interface and thereby significantly extends the service life of the insert. And, as explained above, the volume, velocity or other character of the jet of coolant fluid may be selectively changed simply by replacing the clamp member with another clamp having different nozzle or orifice characteristics.
A further embodiment of the present invention is shown generally at 136 of FIGS. 13-16 wherein a threading or cutting insert holding tool, referred to as a JET-STREAM™ ON-EDGE™ threading and grooving bar or tool, and embodying the principles of the present invention, is shown to support a threading or grooving metal cutting insert positioned on its edge rather than being horizontally positioned and supported as shown in FIGS. 1-12. The threading or cutting insert holding tool 136 is shown to have an elongate shank 138 of square or rectangular cross-sectional configuration and with a cutting insert support and coolant fluid distribution head structure 140 that is integral with the shank. A generally triangular cutter insert seat 142 is formed in a side portion of the insert support and coolant fluid distribution head structure 140 and is defined in part by insert support surfaces 144, 146 and 148 which stabilize a threading or grooving cutter insert 150. A cutter retaining and coolant fluid distribution clamp member 152 is retained in clamping position on the cutting insert support and coolant fluid distribution head structure 140 by means of a clamp retaining screw 154. An insert retaining projection 156 extends downward from a front portion of the clamp 152 and is positioned to establish retaining or locking engagement with the cutter insert and to ensure that the cutter insert is retained within its seat during machining operations. The insert retaining projection 156 defines a downwardly facing support shoulder surface 157 that is disposed for retaining engagement with a top surface 159 of the threading or grooving insert. The clamping force of the clamp member is applied to the top surface 159 and thus prevents the insert 150 from being moved upwardly within its cutter recess by machining forces. The insert retaining projection 156 also defines a side support surface 161 which applies a side locking force to the threading or grooving insert to further restrain the insert within its seat recess. The clamp and its insert retaining projection 156 function to provide efficient stabilized support for the cutter insert even during the initial heavy-cut machining that is typically employed in production facilities.
For the purpose of directing one or more jets of coolant fluid precisely at the threading or grooving interface of the cutter insert with the workpiece during machining operations the clamp retainer screw 154 defines a threaded shank, such as is shown at 40 in FIG. 2 and at 116 in FIG. 7, which is threaded into an internally threaded bore 158. The clamp retainer screw 154 may be identical with the clamp retainer screws 42 and 114 which are described above. The clamp member 152 defines an internal coolant fluid distribution passage shown in broken line at 160 which terminates at a jet orifice or nozzle 162 that is located on a side portion of the clamp member 152 and is oriented to direct a jet of coolant fluid directly onto the threading or grooving point or edge 164 of the insert. In the event that additional or less flow of coolant fluid is desired for a particular aspect of the machining operation it is a simple process to remove the clamp and coolant fluid distribution member 152 and replace it with a different clamp and coolant fluid distribution member having a jet orifice or nozzle of a different dimension and configuration. Coolant fluid supply to the clamp and coolant fluid distribution clamp member is provided by a coolant fluid supply fitting 166 which is threaded into an internally threaded portion 168 of a coolant fluid supply passage 170 of the head structure 140 and to the internal longitudinal and transverse coolant flow passages of the clamp retainer screw 154.
The clamp and coolant fluid distribution member 152 defines a depending locking projection 172 having a tapered cam surface 174 that is disposed for camming engagement with a corresponding tapered surface 176 that forms a surface of a locking recess 178. During tightening rotation of the clamp retainer screw 154 the tapered cam surface 174 establishes camming engagement with the corresponding tapered surface 176 and develops downward and rearward forces on the clamp member that urge the threading or grooving insert tightly into its recess. This feature significantly minimizes the potential for any movement of the threading or grooving insert relative to the cutter support head portion 140 of the cutter insert holding tool 136. To further stabilize the clamp member 152 during machining operations and to ensure precisely oriented positioning of the clamp member relative to the cutter support head 140 the rear portion of the clamp member defines an orienting pin recess 180 within which is received an orienting and anti-rotation pin 179 which is of the same configuration and function as the orienting pins shown at 76 in FIG. 4 and 129 in FIG. 9. The orienting and anti-rotation pin 179 is also received within a pin receptacle of the cutter support head portion 140 to ensure against any rotation of the clamp member relative to the cutter support head.
As shown in the exploded isometric illustration of FIG. 15, sealing of the clamp member to the cutter support head portion 140 may be accomplished by an O-ring type resilient seal 182 which becomes compressed as the clamp member is tightened. Sealing of the retainer screw 154 to the clamp member 152 may be achieved by a resilient sealing washer 184 which may be backed up by a metal washer 186 orienting and. Preferably, however, the sealing arrangement will take the form shown in FIG. 4 where resilient O-ring seals such as shown at 58 and 60 are mechanically compressed between metal components to establish sufficient sealing capability to withstand the pressure range of the flowing coolant fluid.
With reference to FIGS. 17-24 a metal cutting insert holding tool is shown generally at 190 and is typically described as a JETSTREAM™, DOR-NOTCH™ threading and grooving tool. The threading and grooving tool 190 is composed of a square or rectangular tool shank 192 having an integral threading or grooving insert support head 194. The threading or grooving insert support head is machined to define a cutter recess 196 within which is received a threading or grooving insert 198 having a cutting edge 200 for metal cutting engagement with a rotating or other moving workpiece. The cutter recess 196 defines an upwardly facing support surface 202 on which the insert 198 is supported and defines an angulated support shoulder 203 which serves to capture and provide rearward support for an angulated rearward surface 204 of the insert 198. At the juncture of the surfaces 202 and 203 there is provided a relief region 205 which provides for complete seating of the insert on the surfaces 202 and 203 without causing interference with an opposite cutting edge of the insert The threading or grooving insert 198 also defines an angulated retainer groove 206, best shown in FIG. 19 which is engaged by a downwardly projecting locking portion 208 of a cutter retaining and coolant fluid distribution clamp member 210.
The downwardly projecting locking portion 208 defines a curved or tapered surface 212 which is disposed for force transmitting engagement with an inclined or curved surface 214 of the angulated retainer groove 206 such that when clamping force is applied to the insert by the clamp member 210 downward and rearward resultant forces are transmitted to the insert 198 and serve to force the insert tightly against the insert surfaces 202 and 203. These downward and rearward forces are defined by the force vector diagram of FIG. 4A and are developed as a clamp retainer screw 216 is tightened such as by means of an Allen or Torx wrench which engages within a wrench receptacle 218. If desired the angulated retainer groove 206 and the downwardly projecting locking portion 208 may have essentially identical configurations, thus causing the insert to be firmly clamped within its seat 196 as the clamp retainer screw is tightened. The clamp and coolant distribution member 210 is provided with a downwardly extending rear projection 220 which is received within a groove 222 that is formed in the upper surface portion of the cutter insert supporting head 194. As the clamp and its downwardly extending projection 220 are driven downwardly by the force of the clamp retainer screw 216, the curved or tapered surface 212 reacts with the tapered surface 206 of the insert 198 and causes application of downward and rearward forces to the clamp member 210 and thus causes downward and rearward force to be applied to the threading or grooving insert 198, further developing forces on the insert to secure it firmly within the insert recess and prevent its movement, vibration or chattering as machining operations progress.
For cooling of the machining interface of the cutting edge of the insert member 198 with the rotating workpiece a coolant fluid supply fitting 224 is threaded into an internally threaded outer portion 226 of a coolant supply passage 228 and is adapted to receive a coolant fluid supply hose, not shown, that extends from the discharge of a coolant pump of a metal working machine. The coolant supply passage 228 is in fluid communication with an internally threaded bore 230 in which the externally threaded shank 232 of a clamp retainer screw 234 is threaded. The clamp retainer screw 234 is preferably of similar construction and function as compared with the clamp retainer screw 42 of FIG. 4 and defines longitudinal and transverse coolant fluid flow passages that transfer flowing coolant fluid from the coolant fluid supply passage 228 to one or more coolant fluid distribution passages 240 as shown in broken line in FIG. 17 which are defined within an insert clamp and coolant distribution clamp member 242. The discharge terminus of the coolant fluid distribution passage 240 defines a coolant jet nozzle or orifice 244 which is located in overlying relation with the cutting insert and is positioned very close to the cutting interface. The jet nozzle is oriented to direct a jet of coolant fluid directly at the machining or cutting interface of the cutting edge 200 of the threading or grooving insert 198 with a rotating workpiece and thus causes continuous and efficient cooling of the cutting interface during machining.
Referring now to FIG. 20 a threading and grooving bar is shown generally at 250 and is referred to as a JETSTREAM™, DOR-NOTCH™ boring bar. The boring and grooving bar 250 comprises an elongate shank 252 which is shown to be of octagonal cross-sectional configuration, but may have any other suitable configuration within the spirit and scope of the present invention. The elongage shank 252 is drilled or otherwise machined to define an internal longitudinal coolant fluid supply passage 254 and a coolant supply fitting 256 is threaded into an internally threaded outer end 258 of the coolant fluid supply passage 254. The fitting 256 is adapted for releasable connection with a coolant fluid supply hose, not shown, that extends from the discharge of a coolant fluid pump with which a metal working machine is provided. The longitudinal coolant fluid supply passage 254 is in communication with another drilled bore 260 which extends into a cutting insert support head structure 262 which is integral with the elongate shank 252. The outer extent of the drilled bore 260 is provided with a removeable chip removal nozzle 264 from which coolant fluid is projected to a region adjacent the metal cutting insert as a jet of sufficient velocity and volume to continuously remove the typical accumulation of metal cuttings or chips that often accumulate. If not removed, this accumulation of metal chips can interfere with a machining process. The chip removal nozzle is typically threaded into the outer extent of the drilled bore 260 and thus is easily unthreaded, removed and replaced with a different nozzle having an orifice of differing size and geometry for the character of chip removal that is needed.
The threading and grooving bar 250 includes an integral cutter insert support head 266 which defines a cutter insert recess 268 within which a threading or grooving insert member 270 is seated. The cutter insert recess 268 defines bottom, side and end support shoulder surfaces, 272, 274 and 276 respectively, which provide for support and stabilization of the threading or grooving insert 270. The insert recess also defines a relief region 278 to permit the threading or grooving insert to be positively seated on each of the support shoulder surfaces. The insert 270, like the insert 198 of FIGS. 17-19 defines transverse grooves such as shown at 280, one of which is engaged by a depending projection 282 of a clamp and coolant distribution member 284. The configuration of the transverse groove and the configuration of the depending projection 282 function cooperatively to cause the threading or grooving insert to be forced into fully seated and supported relationship with the insert recess surfaces in the same manner as discussed above in connection with FIGS. 17-19.
The clamp member 284 is secured in insert retaining relation with the insert support head 254 by means of a clamp retainer screw 286 which defines a threaded screw shank 288 that extends through a passage 290 of the clamp member 284 and is received by an internally threaded passage 292 of the insert support head. The clamp retainer screw 286 defines longitudinal and transverse flow passages, such as shown in FIG. 4, for conducting flowing coolant fluid from the passage that is defined by the drilled bore 260 The clamp member 284 to an internal coolant fluid distribution passage 294.
As depicted by the isometric illustration of FIG. 25, a coolant fluid seal assembly shown generally at 300 is employed to minimize the potential for leakage of coolant fluid along the exterior flats 302 of a boring bar 304 or other fluid transporting tool holder mechanism for replaceable cutter inserts 306. A tool holder 308 of a machining system defines an internal tool receptacle 310 within which a boring bar or other machine tool is received as shown in FIG. 27. Retainer screws 312 are employed in conventional manner to secure the boring bar within the tool receptacle. During machining operations coolant fluid is pumped into a tool receptacle space 314 and traverses a longitudinal coolant fluid flow passage 316 of the boring bar to internal fluid passages of the cutter insert support head 318 and to the cooling and chip removal jets as explained above.
When the boring bar or other cutter support tool has external flats for efficiency of tool support and orientation, which is often the case, coolant fluid may have a tendency to leak along the longitudinal space that is defined by the clearance of the flats of the cutter support tool with the circular internal surface of the machine tool receptacle. To seal this potential for coolant fluid leakage, a seal support member 320 is positioned about the machine tool and is secured in place by one or more set screws 322 or any other suitable retainer member. The seal support member 320 defines a circular seal pocket 324 within which is received a circular seal member 326 composed of deformable resilient sealing material, such as rubber, soft polymer material or the like which is resistant to deterioration by contact with the coolant fluid medium. The seal support member 320 defines an external threaded section 328 which is received within an internally threaded section 330 that defines a portion of a circular seal retainer pocket 332 of a seal retainer member 334. The seal retainer member defines a planar circular retainer shoulder 335 that provides adequate support for the annular seal member and permits substantial mechanical deformation of the seal member as it is deformed to the configuration of the internal clearances. If desired, the external surface 336 of the seal retainer member 334 may be knurled or otherwise roughened to permit its manual tightening on the annular seal support member 330. Also, if desired, the seal retainer member may be secured in place by means of one or more set screws if desired. Generally, however, manual tightening is sufficient to deform the seal member and secure the seal retainer in place, since the resilient seal develops frictional resistance to minimize undesired rotation of the seal retainer due to the vibration of machining operations.
The annular seal member 326 has significant cross-sectional dimension thus enabling it to be mechanically deformed to the configuration shown in FIG. 28 so that it essentially fills the clearance that is defined by the flats and any circular clearance of the boring bar and develops a fluid tight seal that withstands the pressure of the coolant fluid
Referring now to FIGS. 33-38 a tool and tool holder assembly similar to that of FIG. 25 is shown generally at 340, wherein a boring bar 344 or other suitable machining insert holding tool is shown to have flats 342 extending along a substantial portion of the length thereof. The boring bar 344 is shown to have a head portion providing for support and positioning of a metal cutting insert 346. A machining system of conventional nature is provided with a tool holder 348 having a receptacle within which a portion of the boring bar is located. Set screws 350 extend through threaded openings and establish releasable retaining engagement with the boring bar as is evident from the longitudinal sectional view of FIG. 37. By engaging a flat surface of the boring bar maximum surface to surface contact of the set screws with the boring bar is achieved, thus providing for optimum retention and stabilization of the boring bar within the tool receptacle of the tool holder.
FIGS. 34 and 35 show a seal retaining bushing member 352 of tubular configuration which defines a circular seal receptacle within which is located an annular seal member 354 being composed of deformable resilient sealing material. The seal retaining bushing member 352 also defines an externally threaded flange 360 to which is threaded a seal retainer member 334 as shown in FIGS. 36 and 37. The seal retaining bushing member 352 is sized with respect to the external dimension of the boring bar and the internal dimension of the cylindrical internal surface 372 of the boring bar receptacle 374 and provides for efficient stabilization of the boring bar during machining processes. An external circular sealing member 362 is positioned within a circular seal receptacle that is located adjacent the externally threaded flange 360 of the seal retaining bushing member 352 and functions to establish sealing engagement within the internal surface 372 of the boring bar receptacle 374 of the tool holder 348 as is evident from FIG. 37. The seal retaining bushing member 352 defines an elongate slot 358 having curved ends, as shown in FIG. 35, through which two of the set screws 350 extend and establish clamping engagement with the upper flat surface of the boring bar.
With the boring bar positioned within the tool receptacle of the tool holder sealing between the tool bar and the bushing member 352 is established by the annular seal 362. For sealing to prevent leaking of cooling fluid along the flats of the boring bar an annular deformable resilient seal member 354 is positioned within the annular seal pocket of the bushing member and a seal retainer member 334 is threaded onto the threaded flange 360 and tightened sufficiently to deform the sealing member and fill the clearance areas between the flats of the boring bar and the internal cylindrical surface 372 of the tool receptacle 374. Tightening of the seal retainer may be accomplished manually or through use of a simple tool such as a spanner wrench. If desired, set screws may be employed to ensure against undesired rotational movement of the seal retainer due to the vibration of machining operations.
In view of the foregoing it is evident that the present invention is one well adapted to attain all of the objects and features hereinabove set forth, together with other objects and features which are inherent in the apparatus disclosed herein.
As will be readily apparent to those skilled in the art, the present invention may easily be produced in other specific forms without departing from its spirit or essential characteristics. The present embodiment is, therefore, to be considered as merely illustrative and not restrictive, the scope of the invention being indicated by the claims rather than the foregoing description, and all changes which come within the meaning and range of equivalence of the claims are therefore intended to be embraced therein.
Patent Application
20070283794
