Patent Application
20110052338
1. Field of Invention
The present disclosure relates generally to a system and method of delivering fluid through a machining element. More specifically, the present disclosure is directed to a tool adapted to receive a flow of cooling fluid into a machining element holder, that then flows through the machining element.
2. Description of Prior Art
Machining elements, such as drill bits, reamers, grinders, saws and like, that are used for machining through a workpiece typically remove particles of the material making up the workpiece. The removed particles can sometimes become wedged between the machining element and the portion of the workpiece being machined. This hinders machining efficiency since the particles may be machined a second time and also through possible additional heating of the machining element.
Machined particles can also become problematic when layers of different material make up the workpiece to be machined. As shown in
Disclosed herein is a tool for cooling a machining element during use and optionally, for removal of chips produced during machining. In one example the tool is for machining a workpiece and includes an annular seal assembly, a collet chuck inserted through the annular seal assembly and rotatable with respect to the seal assembly, an annulus in the collet chuck, a machining element affixed on an end of the collet chuck, a passage formed through the machining element, so that the end of the machining element opposite the collet chuck is in fluid communication with the annulus, a drive source coupled to an end of the collect chuck opposite the machining element, a housing circumscribing the seal assembly and a portion of the rotating drive source, and a fluid flow line extending through an opening in the housing and having an end at the seal assembly and in fluid communication with the annulus, so that fluid flowing through the fluid flow line into the annulus is flowable through the passage in the machining element.
Also disclosed is a system for machining workpieces that includes a drive source having a hand grip, a selectively rotatable and extendable drive shaft, and a housing circumscribing the drive shaft. Further included with the system is a collet chuck having an end coupled with the drive shaft, a machining element coupled in an end of the collet chuck opposite the drive shaft, a cutting surface on the machining element, a cavity in the collet chuck in fluid communication with a fluid flow, and a passage formed within the machining element having an end in fluid communication with the cavity and an end adjacent the cutting surface, so that fluid flow provided to the cavity flows through the passage and adjacent the cutting surface.
Another embodiment disclosed herein is a drill with a cooling system that includes a handheld drill motor, a drive shaft selectively rotatable and selectively extendable from the drill motor, a bit holder having an end affixed to the drive shaft, a sealed cavity in the bit holder, a rotary seal circumscribing the bit holder having an outer diameter about twice the diameter of the bit holder, a supply of cooling fluid in fluid communication with the cavity, and a drill bit attached to the end of the bit holder opposite the drive shaft.
Some of the features and benefits of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which:
It will be understood the improvement described herein is not limited to the embodiments provided. On the contrary, the present disclosure is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the improvement as defined by the appended claims.
The improvement(s) of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings in which disclosed embodiments are shown. The disclosed improvement(s) may, however, be embodied in many different forms and should not be construed as limited to the illustrated embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be through and complete, and will fully convey the scope of the disclosure to those skilled in the art. Like numbers refer to like elements throughout.
It is to be understood that the improvement(s) described herein is not limited to the exact details of construction, operation, exact materials, or embodiments shown and described, as modifications and equivalents will be apparent to one skilled in the art. In the drawings and specification, there have been disclosed illustrative embodiments and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation. Accordingly, applicants' improvement(s) is therefore to be limited only by the scope of the appended claims.
Coupled on the spindle 44 is a collet chuck 48 shown having an elongated body 50. A receptacle 52 is formed to receive the spindle 44 therein. The receptacle 52 is provided on the end of the body 50 adjacent the drive source 42. The coupling between the spindle 44 and the receptacle 52 may include threads, splines, pins, or any other known way of fastening mechanical members. The receptacle 52 terminates at a bulkhead 54, which defines a substantially solid portion of the body 50. A cavity 56 is within the body 50 on the side of the bulkhead 54 opposite the receptacle 52. Cavity 56 has an elongate side oriented along the direction of the tool axis Ax. The cavity 56 as shown in
A machining element 60, such as a drill bit, is shown attached to the body 50 and aligned substantially parallel with the axis Ax. A collet nut 62 is affixed on the open end 58 having an aperture 61 through its mid-section in which a shank of the machining element 60 is retained and affixed to the collet chuck 48. The machining element 60 as shown in
An optional connector 68 is shown attached on the terminal end of the drive source housing 46. In another embodiment, the drive source housing 46 may encompass the collet chuck 48 in place of the connector 68. The connector 68 circumscribes a portion of the collet chuck 48 and shown as a generally annular member. Alternatively, the connector 68 may not fully circumscribe the collet chuck 48, but instead may be one or more elongated elements extending from the drive source housing 46 along the tool axis Ax. In the embodiment shown, an elongated slot 69 is provided through a wall of the connector 68; with the slot's 69 elongate length substantially aligned with the tool axis Ax. A fluid flow line 70 is shown in sectional view extending through the slot 69 and into fluid communication with the cavity 56.
Circumscribing the collet chuck 48 is a rotary seal assembly 74 that facilitates coupling between the flow line 70 and cavity 56. As shown, the seal assembly 74 includes a sleeve-like annular body and is positioned adjacent the bulkhead 54. The bulkhead 54 outer diameter is greater than the collet chuck 48 diameter over which the sleeve body 76 is disposed, thereby providing a shoulder against which the sleeve 76 is set. Bearings 78, which may optionally be sealed ball, roller, or needle bearings, are provided between the sleeve 76 and collet chuck 48. Thus, the sleeve 76 may remain substantially stationary as the collet chuck 48 rotates. The sealed bearings 78 also form a pressure barrier between the collect chuck 48 and sleeve body 76. Grooves 79 are shown provided in the sleeve 76 inner surface and configured to receive the bearings 78 therein. Snap rings 80 are set into recesses in the sleeve 76 inner surface and retain the bearings 78 within the grooves 79. The seal assembly 74 is kept in place by an annular retention nut 82 shown coaxially circumscribing the collet chuck body 50 on a side of the seal assembly 74 opposite the bulkhead 54. The retention nut 82 is attached to the collet chuck body 50, such as by corresponding threads. An inner radial portion of the retention nut 82 applies an axial force against the bearings' 78 race adjacent the chuck 48 body, but is out of contact with the bearings' 78 race adjacent the sleeve body 76. Thus the bearings' 78 race adjacent the collet chuck 48 rotates along with collet chuck 48 rotation. Whereas the bearings' 78 race adjacent the sleeve 76, can remain stationary. An optional washer 83 may be provided between the retention nut 82 and the bearings' 78 race adjacent the collet chuck 48 for transferring the axial force between the nut 82 and bearings 78.
Radially formed through the non-rotating sleeve body 76 is a port 84 on which the flow line 70 is attached. A gallery annulus 88 is shown circumscribing the rotatable collet chuck body 50 beneath the seal assembly 74. Therefore the port 84 registers with the annulus 88 during full rotation of the collet chuck 48. One or more openings 86 are formed through the collet chuck body 50 between the annulus 88 and cavity 56. The opening(s) 86 provide fluid communication between the annulus 88 and the cavity 56 so that fluid flowing through the flow line 70 and port 84 can freely flow into the cavity 56. Accordingly, introducing fluid into the cavity 56 causes fluid to flow through the passage 64 and exit the machining element 60 proximate the cutting surface 65. The fluid removes thermal energy within the machining element 60 due to machining or other sources. Moreover, after the fluid flow exits the passage 64, it becomes a cleaning source by sweeping away machined particles in its flow stream and moves them away from the cutting surface. This eliminates the low efficiency of machining the same piece of material twice and can also significantly reduce the chances of a harder particle eroding a softer material.
An optional nosepiece 66 is shown included with the tool assembly 40 of
Referring now to
As noted above, the spindle 44A is coupled with the collet chuck 48 via a receptacle 52A and the chuck body 50A. Therefore, rotational and/or axial movement of the spindle 44A is imparted to the collet chuck 48A and on to the machining element 60A. A fluid supply 71 is provided in the embodiment of
As shown, the nosepiece 66A is coupled with a template-like drill plate 90 on which a coupling 92 is provided that is configured to mate with a coupling 75A provided on the nosepiece 66A. The drill plate 90 is attached to a workpiece 95 that is to be machined using the tool assembly 40A. Therefore the coupling 92 is strategically placed so that by extending the machining element 60A as aligned per the respective couplings 75A, 92, a corresponding drill hole 94 can be formed through the workpiece 95. An optional pilot hole 93 is provided in the drill plate 90 through which the machining element 64A can pass.
A detailed example of a drill hole 94 being formed in the workpiece 95 is shown in a side partially sectional view in
An alternative machining element 60B is illustrated in perspective view in
The present system and method described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. These and other similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present disclosure and the scope of the appended claims.
