Power tool with interchangeable tool head
09724799 · 2017-08-08
Assignee
Inventors
- Wade C. King (Finksburg, MD, US)
- Micah A. Coleman (Baltimore, MD, US)
- Andrew Walker (Newton Hall, GB)
- Jason McRoberts (Red Lion, PA, US)
- Frederick R. Bean (Finksburg, MD, US)
- Christopher J. Murray (Baltimore, MD, US)
- Frank A. DeSantis (Bel Air, MD, US)
Cpc classification
B24B23/03
PERFORMING OPERATIONS; TRANSPORTING
B24B23/04
PERFORMING OPERATIONS; TRANSPORTING
B24B41/04
PERFORMING OPERATIONS; TRANSPORTING
Y10T29/4987
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B24B49/00
PERFORMING OPERATIONS; TRANSPORTING
Y10T29/49826
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
B24B41/04
PERFORMING OPERATIONS; TRANSPORTING
B24B49/00
PERFORMING OPERATIONS; TRANSPORTING
B24B45/00
PERFORMING OPERATIONS; TRANSPORTING
B24B23/03
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A power tool that includes a tool body housing, a drive system, a tool head and a connection system. The drive system is housed in the tool body housing. The tool head, which is configured to perform work on a work piece, includes a tool head housing and an input member that is driven by the drive system when the tool head is coupled to the tool body housing. The tool head can be engaged to the tool body housing in at least two pre-defined and distinct orientations. The connection system secures the tool head to the tool body housing in each of the at least two pre-defined and distinct orientations.
Claims
1. A power tool comprising: a tool body housing at least partly formed by a pair of clam shell housing members, the tool body housing defining a cavity; a drive system housed in the cavity, the drive system having an output member; a tool head that is configured to perform work on a work piece, the tool head including a tool head housing and an input member, the input member that is matingly engagable to the output member to drivingly couple the output member of the drive system to the input member of the tool head when the tool head is coupled to the tool body housing; and a connection system having at least one recess and a retainer, the at least one recess being formed in one of the tool head housing and the tool body housing, the retainer being movably coupled to the other one of the tool head housing and the tool body housing, the retainer being received into the at least one recess to fixedly but removably couple the tool head to the tool body housing; wherein the tool head can be engaged to the tool body housing in at least two pre-defined and distinct orientations and wherein the connection system secures the tool head to the tool body housing in each of the at least two pre-defined and distinct orientations; wherein one of the tool head and the tool body housing includes a mounting hub and wherein the other one of the tool head and the tool body housing includes a recess into which the mounting hub is received; wherein the mounting hub comprises a cylindrical structure; and wherein one or more nubs is formed on the periphery of the mounting hub, the one or more nubs being configured to be received in notches formed in the other one of the tool head and the tool body housing.
2. The power tool of claim 1, wherein the one of the tool head and the tool body housing includes a plurality of legs that interlock to the other one of the tool head and the tool body housing.
3. The power tool of claim 2, wherein the legs are received into pockets formed into the other one of the tool head and the tool body housing.
4. The power tool of claim 1, wherein the mounting hub comprises a cylindrical structure.
5. A power tool comprising: a tool body at least partly formed by a pair of clam shell housing members, the clam shell housing members defining a cavity; a drive system housed in the cavity, the drive system having a pneumatic motor and an intermediate output member that is driven by the pneumatic motor; and a tool head configured to perform work on a workpiece, the tool head having a tool head housing and an intermediate input member; wherein one of the tool body and the tool head housing defines a mount, wherein the other one of the tool body and the tool head housing defines a mount aperture that receives the mount, wherein the tool head is selectively interlocked to the tool body when the mount is inserted into the mount aperture, and wherein the intermediate input member is matingly engaged with the intermediate output member when the tool head is interlocked to the tool body; and wherein the clam shell housing members cooperate to define a first handle with a portion that is configured to be gripped by a hand of a user of the power tool, wherein the intermediate output member is rotatable about a rotational axis, and wherein the first handle has a first longitudinal axis that is aligned to a predetermined angle relative to the rotational axis, the predetermined angle being sized so that the longitudinal axis is closer to being parallel to the rotational axis than being perpendicular to the rotational axis.
6. The power tool of claim 5, wherein one of the tool body and the tool head housing further comprises a plurality of rails and wherein the other one of the tool body and the tool head housing defines a plurality of rail cavities that receive the rails when the mount is inserted into the mount aperture.
7. The power tool of claim 5, wherein the mount aperture defines a hub cavity and a plurality of rail cavities, and wherein the mount defines a cylindrical hub and a plurality of rails, the cylindrical hub extending longitudinally along the rotational axis and being configured to be received into the hub cavity, the rails being disposed about the cylindrical hub and extending parallel to the rotational axis, the rails being configured to be received into the rail cavities when the cylindrical hub is received into the hub cavity.
8. The power tool of claim 7, wherein at least one recess is formed in one of the tool head housing and the tool body, wherein a retainer is movably coupled to the other one of the tool head housing and the tool body, the retainer being received into the at least one recess to fixedly but removably couple the tool head to the tool body.
9. The power tool of claim 7, wherein the rails are integrally and unitarily formed with the cylindrical hub.
10. The power tool of claim 7, wherein the rails number four in quantity.
11. The power tool of claim 7, wherein the rail cavities are disposed symmetrically about the hub cavity.
12. The power tool of claim 7, wherein the rail cavities intersect the hub cavity.
13. The power tool of claim 5, further comprising a connection system having at least one recess and a retainer, the at least one recess being formed in one of the tool head housing and the tool body, the retainer being movably coupled to the other one of the tool head housing and the tool body, the retainer being received into the at least one recess to fixedly but removably couple the tool head to the tool body.
14. A power tool comprising: a tool body housing that defines a cavity; a drive system housed in the cavity, the drive system having an output member; a tool head that is configured to perform work on a work piece, the tool head including an input member that is matingly engageable to the output member to drivingly couple the output member of the drive system to the input member of the tool head when the tool head is coupled to the tool body housing; and a connection system having at least one groove and a retainer, the at least one groove being formed in one of the tool head and the tool body housing, the retainer being movably coupled to the other one of the tool head and the tool body housing, the retainer being received into the at least one groove to fixedly but removably couple the tool head to the tool body housing; wherein the tool head includes an attachment hub and wherein the tool body housing includes a mount aperture into which the attachment hub is received; and wherein a forward surface of the attachment hub is substantially flush with a forward surface of the input member; and wherein the output member includes a plurality of male splines and the input member comprises a plurality of female splines that receive the male splines.
15. The power tool of claim 14, wherein the retainer comprises a wire member, the wire member is housed in the tool body housing and has a pair of opposite engagement arms that extend into the mount aperture, a push button being coupled to the wire member and slidable between a first position and a second position.
16. The power tool of claim 15, wherein the engagement arms are received into the at least one groove to inhibit movement of the tool head along a rotational axis of the output member in a direction away from the tool body housing, the input member being drivingly coupled to the output member for rotation therewith.
17. The power tool of claim 16, wherein the wire member biases the push button into the first position and wherein movement of the push button into the second position spreads the engagement arms apart from one another to permit the tool head to be withdrawn from the tool body housing along the rotational axis.
18. The power tool of claim 14, wherein the attachment hub has a chamfered leading edge.
19. The power tool of claim 14, wherein the attachment hub is cylindrical.
20. The power tool of claim 14, wherein the tool head includes a sanding platen.
21. The power tool of claim 14, wherein the tool head further comprises a projection spaced apart from the attachment hub and projecting towards the tool body housing along an axis that is parallel to a longitudinal axis of the input member; and wherein the tool body housing comprises an aperture into which the projection is received.
22. The power tool of claim 14, wherein one of the tool body housing and the tool head comprises a projection and the other of the tool body housing and the tool head comprises a pocket which receives the projection; and wherein the pocket has a rectangular cross-section.
23. The power tool of claim 14, wherein one of the tool body housing and the tool head comprises a projection and the other of the tool body housing and the tool head comprises a pocket which receives the projection, and wherein the projection and pocket are spaced apart from the attachment hub and the mount aperture.
24. The power tool of claim 21, wherein the retainer comprises a wire member and a push button, the wire member being housed in the tool body housing and having a pair of opposite engagement arms that extend into the mount aperture, the push button being coupled to the wire member and slidable between a first position and a second position; wherein the engagement arms are received into the at least one groove to inhibit movement of the tool head along a rotational axis of the output member in a direction away from the tool body housing; and wherein the wire member biases the push button into the first position and wherein movement of the push button into the second position spreads the engagement arms apart from one another to permit the tool head to be withdrawn from the tool body housing along the rotational axis.
25. The power tool of claim 22, wherein the retainer comprises a wire member and a push button, the wire member being housed in the tool body housing and having a pair of opposite engagement arms that extend into the mount aperture, the push button being coupled to the wire member and slidable between a first position and a second position; wherein the engagement arms are received into the at least one groove to inhibit movement of the tool head along a rotational axis of the output member in a direction away from the tool body housing; and wherein the wire member biases the push button into the first position and wherein movement of the push button into the second position spreads the engagement arms apart from one another to permit the tool head to be withdrawn from the tool body housing along the rotational axis.
26. A power tool comprising: a tool body housing that defines a cavity; a drive system housed in the cavity, the drive system having an output member; a tool head that is configured to perform work on a work piece, the tool head including an input member that is matingly engageable to the output member to drivingly couple the output member of the drive system to the input member of the tool head when the tool head is coupled to the tool body housing; and a connection system having at least one groove and a retainer, the at least one groove being formed in one of the tool head and the tool body housing, the retainer being movably coupled to the other one of the tool head and the tool body housing, the retainer being received into the at least one groove to fixedly but removably couple the tool head to the tool body housing; wherein the tool head includes an attachment hub and wherein the tool body housing includes a mount aperture into which the attachment hub is received; and wherein one of the tool body housing and the tool head comprises a projection and the other of the tool body housing and the tool head comprises a pocket that receives the projection; wherein the projection and pocket are spaced apart from the attachment hub and the mount aperture; wherein the pocket has a rectangular cross-section; and wherein the retainer comprises a wire member and a push button, the wire member being housed in the tool body housing and having a pair of opposite engagement arms that extend into the mount aperture, the push button being coupled to the wire member and slidable between a first position and a second position; wherein the engagement arms are received into the at least one groove to inhibit movement of the tool head along a rotational axis of the output member in a direction away from the tool body housing; and wherein the wire member biases the push button into the first position and wherein movement of the push button into the second position spreads the engagement arms apart from one another to permit the tool head to be withdrawn from the tool body housing along the rotational axis.
27. A power tool comprising: a tool body at least partly formed by a pair of clam shell housing members, the clam shell housing members defining a cavity; a drive system housed in the cavity, the drive system having a motor and an intermediate output member that is driven by the motor; and a first tool head configured to perform work on a workpiece, the first tool head having a first tool head housing and an intermediate input member; wherein one of the tool body and the first tool head housing defines a mount, wherein the other one of the tool body and the first tool head housing defines a mount aperture that receives the mount, wherein the first tool head is selectively interlocked to the tool body when the mount is inserted into the mount aperture, and wherein the intermediate input member is matingly engaged with the intermediate output member when the first tool head is interlocked to the tool body; wherein the first tool head can be engaged to the tool body housing in at least two pre-defined and distinct orientations and wherein a connection system secures the first tool head to the tool body housing in each of the at least two pre-defined and distinct orientations; wherein the connection system is configured so that the first tool head can be secured to the tool body housing in a tool-free manner; and wherein one of the intermediate output member and the intermediate input member includes a plurality of male splines and the other of the intermediate output member and the intermediate input member comprises a plurality of female splines that receive the male splines.
28. The power tool of claim 27, wherein the connection system includes a biasing member which helps secure the first tool head to the tool body.
29. The power tool of claim 27, further comprising a second tool head configured to perform work on a workpiece, the second tool head performing a different function than the first tool head and being selectively securable to the tool body in place of the first tool head.
30. The power tool of claim 29, wherein the second tool head can be engaged and secured to the tool body housing in at least two pre-defined and distinct orientations.
Description
DRAWINGS
(1) The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
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DETAILED DESCRIPTION
(31) Example embodiments will now be described more fully with reference to the accompanying drawings. Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
(32) With initial reference to
(33) A mode selector 24 can be arranged on a forward portion of the tool body 12. The mode selector 24 can include a movable member or dial 26 and a pictorial key 28. A base release button 30 can be provided proximate to the mode selector 24. A power cord 32 can extend from the tool body 12 to supply electrical current to the sander 10. It is appreciated that while the sander 10 is shown operatively associated with a power cord 32 for alternating current (AC) operation, the sander 10 can also be configured for operation with other power sources, such as direct current (DC) or a pneumatic input.
(34) The sander 10 will be further described. The drive system 18 can include an electric motor 36 (
(35) With specific reference now to
(36) The finishing sander platen 50 can define a substantially flat bottom surface 62, a curved upper surface 64, and a peripheral edge with a point 66 that provides the finishing sander platen 50 with an iron-shape. The point 66 can be used for sander corners or other areas. In one example, an abrasive sheet (not shown) can be applied to the flat bottom surface 62 by way of a hook and loop fabric fastener. An underside of the abrasive sheet can have a first hook and/or loop surface, which can be attachable to a second hook and/or loop surface (not shown) provided on the flat bottom surface 62 of the finishing sander platen 50.
(37) According to one example, a portion 68 of the finishing sander platen 50, adjacent to the point 66 of the peripheral edge, can be detachable from the remainder of the finishing sander platen 50. The detachable portion 68 can be loosened or completely detached from the finishing sander platen 50 and rotated through 180°, or even replaced, as the edges on either side of the point become worn. Further details of the detachable portion 68 can be found in commonly owned U.S. Pat. No. 5,839,949, which is hereby incorporated by reference as if fully set forth in detail herein. As can be appreciated, the finger attachment portion 56 of the detail sander platen 52 can occupy the space of an otherwise located point 66 (i.e., see finishing sander platen 50). Those skilled in the art will readily appreciate that the shape and configuration of the finishing sander platen 50 and detail sander platen 52 are substantially equivalent, the finishing sander platen 50 being configured for mounting to the tool body 12 with a flat forward end 70 facing toward the front of the sander 10, whereas the detail sander platen 52, having the finger attachment 56, can be secured to the tool body 12 having the finger attachment 56 being oriented toward the forward end of the sander 10. Those skilled in the art will also appreciate that the detail sander platen 52 can also be mounted to the sander 10 without the finger attachment 56.
(38) With specific reference to
(39) The finishing sander platen 50 can further define a centrally located attachment hub 82 and a chute 84. The attachment hub 82 can generally house a rotatable member 88 (
(40) With reference again to
(41) As can be appreciated, the detail sander platen 52 can be constructed similarly to the finishing sander platen 50. Therefore, a detailed description of the detail sander platen 52 will not be repeated. As illustrated, however, a chute 84′ (
(42) With specific attention now to
(43) Turning now to
(44) With renewed reference now to
(45) As mentioned above, the attachment assembly 150 can selectively couple with an identified sander platen 22 without the use of a hand tool (such as a screwdriver or Allen key, etc.). An exemplary method of attaching the finishing sander platen 50 according to one example of the present teachings will now be described with reference to
(46) An exemplary method of releasing the finishing sander platen 50 according to the present teachings will now be described. Again, it is appreciated that releasing other platens (i.e., 52 or 54) will be carried out similarly. A user can push the base release button 30 inwardly (i.e., in a direction leftward as viewed in
(47) With reference now to
(48) An exemplary circuit associated with the mode selector 24 will be described briefly. The speed control switch 188 can include a diode 192. The speed control switch 188 can be electrically connected to an on/off switch 194 of the sander 10. In one example, when the speed control switch 188 is moved to the first or “on” position, current bypasses the diode 192 and the sander 10 runs at full speed. When the speed control switch 188 is turned to the second or “off” position, the current is forced through the diode 192 and the voltage is dropped causing the motor 36 (and, as a result, the output member 38 to rotate at a reduced speed).
(49) With reference again to
(50) According to other examples, indicia can be arranged around the pictorial key 28 that correspond to a grit value of sand paper optimized for a given task. Additionally or alternatively, the pictorial key 28 can have a graphic (e.g. picture, sketch, photograph, etc.) that corresponds to an exemplary article for sander (i.e., a door, a table, a pedestal, etc.). The grit value and picture of the article to be sanded can be arranged as a first inner zone 205, a second inner zone 206, a third inner zone 207, a fourth inner zone 208 and a fifth inner zone 209. It can be appreciated that while the mode selector 24 has been shown and described above in connection to a movable member 26 that rotates around an axis in the form of a dial or pointer, the mode selector can take alternate forms. For example, the mode selector 24 can alternatively comprise a lever configured for linear movement or other configurations.
(51) With reference now to
(52) The plurality of platens 222 can define a finishing sander platen 250 and a random orbit sander platen 254. Other platens may be provided. The detail sander platen 252 can define an attachment hub 260 that includes a series of nubs 262 extending outwardly around a shroud 264 thereof. A female spline 268 can be provided on the finishing sander platen 250 and be configured for meshingly engaging a male spline 270 provided on an electric motor 272 of the drive system 218. The nubs 262 are configured for slidably aligning and inserting into corresponding first and second notches 225 and 227 defined on the ring 226 of the mode selector 224 and the tool body 212, respectively. As can be appreciated, the first plurality of notches 225 will be rotationally aligned with specific second plurality of notches 227 for accepting the correct platen 222 that corresponds with a given graphic provided on the pictorial key 228 aligning with the arrow 230.
(53) The random orbit sander platen 254 can include nubs 274 arranged around an attachment hub 276. A tongue 280 can extend outwardly adjacent from the attachment hub 276. The tongue 280 can be configured to cooperatively nest in a pocket 282 formed on the tool body 212. As illustrated, the nubs 274 are located at a radially distinct location around the attachment of 276 as compared to the nubs 262 arranged around the attachment hub 260. As can be appreciated, once a user rotates the mode selector 224 to a location in which a graphic of the pictorial key 228 that illustrates the random orbit sander platen 254 is aligned with the arrow 230, the nubs 274 cooperatively align with predetermined notches 225 (of the ring 226 of the mode selector 224) and notches 227 (of the tool body 212). As can be appreciated, the rotational orientation of the notches 225, 227 will permit attachment with only the sander platen 222 identified in the pictorial key 228 aligned with the arrow 230. Therefore, attachment of other sander platens 222 is precluded.
(54) It is appreciated that while the above embodiment has been described in association with “notches” and “nubs” other geometries may be provided for selectively keying specific platens to the tool body 212.
(55) While not specifically shown, a rotatable member can be provided in the respective attachment hubs 260 and 276 that can be configured to provide a desired offset and/or counterbalance mass according to a given task. Also, while not specifically shown, the platens 222 can be selectively coupled to the sander 210, such as by way of an attachment assembly (see attachment assembly 150 described above), or other methods of attachment.
(56) Turning now to
(57) The platens 322 can include a finishing sander platen 350, a random orbit sander platen 354, and a square footprint detail sander platen 356. According to one example, a finger, or other structure 360, such as shown on the detail sander platen 356 can be provided for rotating the wheels 326 into a rotational position that corresponds to the zone (i.e., 330, 332, or 334) associated with the attached platen 322 being viewed through the window 324. In one example, a flip key 366 can extend from the output member 338 of the sander 310. The flip key 366 can pass through the corresponding opening 370, shown on the finishing sander platen 350 and rotated to a secured position to lock a given platen 322 relative to the tool body 312. While not specifically shown, a similar opening is defined on the other platens 354 and 356. The flip key 366 can also be provided on other sanders disclosed herein for securing other platens described herein.
(58) Turning now to
(59) Turning now to
(60) As shown in
(61) Turning now to
(62) The wheel 634 can include a first image 664a, a second image 664b, a third image 664c, and a fourth image 664d. The wheel 634 is fixed for rotation with the movable member 630, such that one of the first through fourth images 664a-664d can be viewable through the window 650. The images 664a-664d correspond with the appropriate graphic 644a-644d on the pictorial key 642 according to the desired task identified by the user. Explained further, and as illustrated in
(63) As illustrated in
(64) While not specifically shown, those skilled in the art will appreciate that the first image 664a of the wheel 634 will be viewable through the window 650 when the indicator 640 is pointing at the first zone 644a of the pictorial key 642. Similarly, the third image 644c of the wheel 634 will be viewable through the window 650 of the control panel 632 when the indicator 640 is pointing at the third zone 644c of the pictorial key 642. According to additional examples, the respective images 664a-664d can be provided with different colors indicating that some of the selected modes of sanding can include a change in motor speed. It is also appreciated that the mode selector 624 and related features can be configured for operation with any of the sanders described herein.
(65) Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
(66) The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
(67) When an element or layer is referred to as being “on”, “engaged to”, “connected to” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to”, “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
(68) Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
(69) Spatially relative terms, such as “inner,” “outer,” “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
(70) The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.