Vacuum port cutter

Abstract

A vacuum port cutter includes a housing that has an internal cavity with an open lower end and an internal frustoconical surface formed thereon. A body is at least partially disposed within the cavity and is mounted for translational movement relative to the housing along a first axis and rotational movement about the first axis relative to the housing. A cutting wheel is rotatably mounted about a second axis to the base.

Description

VACUUM PORT CUTTERBACKGROUND

[0001] Composite parts provide lightweight alternatives to metal parts. Composite parts also provide the ability to design parts to have unique mechanical properties not available with metal parts. While composite parts are used extensively throughout a wide variety of industries and technologies, these features make composite parts particularly well-suited for aviation applications.

[0002] Some composites combine carbon fibers, glass fibers, etc. with a cured resin or adhesive using a vacuum bag molding process. During this process, fibers or sheets of fabric impregnated with the uncured resins or adhesives (called ‘‘prepregs’’) are layered on a mold. The layup is then placed within a vacuum bag and sealed. A vacuum port is installed in fluid communication with the inside of the vacuum bag and is configured to be attached to an outside vacuum hose. The vacuum hose draws air out of the bag so that the bag applies pressure to the assembly. The bagged assembly is then cured in an oven, autoclave, or by another suitable heat source.

[0003] FIGURE 1 shows a representative layup 20 used to manufacture composite parts by a vacuum bag molding process. The layup 20 includes an uncured composite part 24 assembled on a mold 22. The composite part 24 is covered by a peel ply 26. A release film 28 is laid over the peel ply 26 and secured to the mold with pressure-sensitive tape 30. A breather layer 32 is placed over the release film 28, and the entire assembly layup is covered with a bagging film 34. In the illustrated embodiment, the bagging film 34 is adhered to the mold using sealant tape 36 so that the composite part 24 and the associated manufacturing layers are positioned in a sealed interior space 40 (between bagging film 34 and the mold 22) that is separated from the ambient environment 42.

[0004] The layup 20 further includes a vacuum port 50 that provides fluid communication between the interior space 40 and a vacuum hose 82. The vacuum hose 82 is coupled to pneumatic fitting 80 formed on the vacuum port 50 so that the hose 82 can draw air from within the interior space 40.

[0005] FIGURE 2 shows a known vacuum port 50 used for vacuum bag molding of composite parts. The vacuum port 50 includes a base 52, which is placed within the interior space 40 during the layup process, and a fitting 64, which is coupled to the base after the bagging film 34 is applied.

[0006] The base 52 includes a frustoconical side surface 54 delimited at an upper edge by a flat top surface 56 and at a bottom edge by a flat bottom surface 58 (see FIGURE 7). A threaded aperture 62 extends axially through the base 52 perpendicular to the top surface 56. One or more vents 60 are formed in the base 52 and extend from the frustoconical side surface 54 to the threaded aperture 62.

[0007] The fitting 64 includes a pneumatic fitting 66 formed on or mounted to a disk-shaped body 68. A threaded protrusion 70 extends from the body 68 opposite the pneumatic fitting 66. The threaded protrusion 70 is sized and configured to threadedly engage the threaded aperture 62 of the base 52 to couple the fitting 64 to the base 52 during use. An aperture 72 extends through the fitting 64 and provides fluid communication between the pneumatic fitting 66 and the vents 60 in the base 52 when the fitting is coupled to the base. An annular gasket 74 surrounds the threaded protrusion 70 and is compressed between the top surface 56 of the base and the body 68 of the fitting 64 to provide an airtight seal between the base and the fitting when the vacuum port 50 is assembled.

[0008] Referring back to FIGURE 1, when the layup 20 is initially assembled, the base 52 is positioned within the interior space 40 of the layup. Before the fitting 64 can be secured to the base 52, a hole needs to be cut in the bagging film 34 to allow the threaded protrusion 70 to pass through bagging film to threadedly engaged the threaded aperture 62 in the base 52. With the fitting 64 secured to the base 52. the gasket 74 and the portion of the bagging film 34 surrounding the hole are compressed between the top surface 56 of the base 52 and the body 68 of the fitting 64 to provide an airtight seal around the threaded protrusion 70. At the same time, the threaded protrusion 70 extends through the bagging film 34 so that the interior space 40 is in fluid communication with the pneumatic fitting 66 through the aperture 72 of the fitting 64.

[0009] Cutting the hole through the bagging film 34 is sometimes done by hand using scissors, a scalpel, or other suitable instruments, however, such methods can be hazardous and can produce inconsistent results. Circular hole cutters are known but are generally designed for cutting on flat surfaces and are difficult to maintain. Some vacuum ports are configured to cut through the bagging film upon installation, but the vacuum ports do not work with all materials. The present disclosure provides a cutter that cuts holes in bagging films in a safe and repeatable matter. The cutter is suitable for use with existing vacuum ports and has durable cutting blades that are easily maintained and / or replaced.SUMMARY[[Note to reviewer(s) - the summary is drafted to provide verbatim support for the language used in the claims provided at the end of the specification. It does not limit the scope of the disclosure or the claims]]

[0010] The present disclosure provides examples of a vacuum port cutter that cuts a circular hole in the bagging film of a composite layup to allow for installation of a vacuum port. In an embodiment, the vacuum port cutter includes a housing that has an internal cavity with an open lower end and an internal frustoconical surface formed thereon. A body is at least partially disposed within the cavity and is mounted for translational movement relative to the housing along a first axis and rotational movement about the first axis relative to the housing. A cutting wheel is rotatably mounted about a second axis to the base.

[0011] In any embodiment, the vacuum port cutter comprises a total of three cutting wheels rotatably mounted to the base.

[0012] In any embodiment, the cutting wheels are positioned to be equally spaced around the first axis.

[0013] In any embodiment, the frustoconical surface has a taper corresponding to a taper of a base of a vacuum port.

[0014] In any embodiment, the vacuum port cutter further comprises a stem extending from the body along the first axis, the stem extending through an upper portion of the housing and having a handled mounted thereto.

[0015] In any embodiment, the vacuum port cutter further comprises a biasing element configured to bias the handle away from the housing.

[0016] In any embodiment, the biasing element is a compression spring engaging the housing and the handle.

[0017] In any embodiment, the body is selectively moveable between a retracted position and an extended position.

[0018] In any embodiment, the vacuum port cutter further comprises a biasing element configured to bias the body toward a retracted position.

[0019] In any embodiment, the vacuum port cutter further comprises a stem extending from the body along the first axis, the stem extending through an upper portion of the housing and having a handled mounted thereto.

[0020] In any embodiment, the stem extends through a central portion of the compression spring.

[0021] In any embodiment, the base includes a planar mounting surface, the second axis being perpendicular to the mounting surface.

[0022] In any embodiment, the cutting wheel is mounted to the base with a fastener and a spring disposed between the cutting wheel and the mounting surface.

[0023] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.DESCRIPTION OF THE DRAWINGS

[0024] The foregoing aspects and many of the attendant advantages of the present disclosure will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

[0025] FIGURE 1 shows a side cross-sectional view of a composite layup of a composite part produced by a vacuum bagging process;

[0026] FIGURE 2 shows a partially exploded view of a vacuum port of the composite layout of FIGURE 1;

[0027] FIGURE 3 shows an isometric view of an embodiment of a vacuum port cutter according to aspects of the present disclosure;

[0028] FIGURE 4 shows a side cross-sectional view of the vacuum port cutter of FIGURE 3;

[0029] FIGURE 5 shows an isometric view of the vacuum port cutter of FIGURE 3 with a housing removed;

[0030] FIGURE 6 shows bottom view of the vacuum port cutter of FIGURE 3;

[0031] FIGURE 7 shows a side cross-sectional view of the vacuum port cutter of FIGURE 3 positioned above the base of a vacuum port;

[0032] FIGURE 8 shows a side cross-sectional view of the vacuum port cutter of FIGURE 7 engaging the base of the vacuum port, wherein the vacuum port cutter includes a cutter assembly in a retracted position;

[0033] FIGURE 9 shows a side cross-sectional view of the vacuum port cutter of FIGURE 8 engaging the base of the vacuum port with the cutter assembly in an extended position; and

[0034] FIGURE 10 shows a side cross-sectional view of the vacuum port cutter of FIGURE 8 disengaging from the base of the vacuum port.DETAILED DESCRIPTION

[0035] The following discussion provides examples of a vacuum port cutter that is used to cut holes in the bagging fdm of a composite part layup. Embodiments of the vacuum port cutter enable a user to safely produce holes sized to accommodate a vacuum port. By enabling a user to drive a cutting assembly in a controlled matter, the vacuum port cutter safely produces holes in an accurate, predictable, and repeatable manner.

[0036] FIGURES 3-6 show a representative embodiment of a vacuum port cutter 100 (“cutter”) according to aspects of the present disclosure. The cutter 100 includes a cutting assembly 110 partially disposed within a housing 150. As will be described in further detail, the cutting assembly 110 is movable in translation relative to the housing 150 along a central axis 190 to engage the cutting assembly with a bagging film to be cut. The cutting assembly 110 is also rotatable about the central axis 190 relative to the housing 150 to drive the cutting assembly 110 in a controlled cutting motion.

[0037] The cutting assembly 110 includes a body 112 with a plurality of mounting faces 114 formed thereon. As best shown in FIGURE 6, the mounting faces 114 of the illustrated embodiment are planar faces positioned such that the body 112 has a cross-sectional shape in the general form of an equilateral triangle.

[0038] A cutting wheel 130 is rotatably coupled to each mounting face 114. Referring to FIGURES 4 and 6 each cutting wheel 130 is rotatable about an axis 192 that is perpendicular to the corresponding mounting face 114. In the illustrated embodiments, a fastener 136, such as a thumb screw, extends through the center of the cutting wheel 130 and secures the cutting wheel 130 to the mounting face 114 while still allowing rotation about the axis 192. A biasing element 134, such as a disc spring or a Belleville washer, is disposed between the cutting wheel 130 and the mounting face 114. The biasing element 134 applies a force that urges the cutting wheel toward the head of the fastener 136. As the result, the cutting wheel 130 maintains contact with the head of the fastener 136 and, therefore, a constant offset from the corresponding mounting face 114.

[0039] Each cutting wheel 130 is a thin circular disc with a circumferential cutting edge 132 extending around the perimeter of the cutting disc. As best shown in FIGURE 4. each cutting wheel 130 is mounted to the corresponding mounting face 114 so that at leasta portion of the cutting edge 132 extends beyond the bottom surface of the body 112. In some embodiments, the cutting edge 132 of each cutting wheel 130 extends beyond the bottom of the body 112 by a distance that is greater than the thickest material to be cut by the cutting assembly. That is, the cutting wheel can completely cut through the bagging film while maintaining a minimal clearance between the body 112 and the bagging film.

[0040] In some embodiments, the body 112 has any suitable number of mounting faces 1 14, each with a corresponding cutting wheel 130 rotatably mounted thereto. In some embodiments, not every mounting face 114 has a corresponding cutting wheel 130. In some embodiments, the mounting faces 114 have any suitable form, number, and orientation.

[0041] As best shown in FIGURES 4 and 6, an elongate stem 116 extends from the upper surface of the body 112 along the central axis 190. A handle 140 is demountably coupled to the stem 116 so that the stem 116 and, therefore, the body 112 of the cutting assembly 110 rotate together about axis 190 and translate together along axis 190. In the illustrated embodiment, the stem 116 is at least partially received within a recess 142 formed in the handle. A flat 118 is formed in the stem 116. and a set screw 144 extends through the handle 140 to engage the flat.

[0042] In some embodiments, the handle 140 is demountably coupled to the stem 116 by any suitable configuration. Removing the handle 140 allows the cutting assembly 110 to be separated from the housing 150. which provides for easier replacement of one ormore cutting wheels 130. In some embodiments, the handle 140 is fixedly coupled to the stem 116, and the cutter 100 is configured to be disassembled or to provide access for cutting wheel 130 replacement without separating the cutting assembly 110 from the housing 150.

[0043] Referring now to FIGURE 4, the housing 150 has a cavity 152 in which the cutting assembly 110 is disposed. A top portion of the housing 150 is delimited by a closeout 154, and the bottom portion of the housing is configured to at least partially receive the base 52 of a vacuum port 50. In this regard, a frustoconical surface 164 is formed on the inner portion of the body 112 at the lower end of the cavity 152. In some embodiments, the interior frustoconical surface 164 of the housing 150 has the same angle as the external frustoconical side surface 54 of the base 52 of the vacuum port 50. The frustoconical surface 164 terminates at a shoulder 166 that extends radially inward from upper edge of the frustoconical surface to the lower edge of the cavity 152.

[0044] Still referring to FIGURE 4, a protrusion 156 extends upward from the closeout 154 at the top of the housing 150. An aperture 158 extends axially through the protrusion 156 and includes a counterbore 160 in the upper end to define a radial shoulder 162.

[0045] A compression spring 170 is partially disposed within the counterbore 160 so that the stem 116 extends through the center of the coils of the spring. A lower end of the spring 170 engages the shoulder 162 of the counterbore 160, and an upper end of the spring 170 engages the handle 140. The spring 170 exerts an upward biasing force on the handle 140 that tends to move the handle 140 away from the housing 150. The biasing force maintains the cutting assembly 110 in a retracted position of FIGURE 4 when the cutter 100 is not in use.

[0046] Referring now to FIGURES 7-10, use of the cutter 100 will now be described. In FIGURE 7, the initial layup 20 has been completed, and the base 52 of the vacuum port 50 is positioned under the bagging film 34. The cutter 100 is positioned above the base 52 and moved downward, as indicated by the arrow, to engage the base 52 through the bagging film 34.

[0047] As shown in FIGURE 8, when the cutter 100 is engaged with the base 52, engagement of the frustoconical side surface 54 of the base 52 with the interior frustoconical surface 164 of the housing 150 limits further downward movement of the cutter. Further, the engagement of the frustoconical surfaces 54 and 164 provides a selfaligning functionality so that the centerline of the threaded aperture 62 of the base 52 is coaxial with the central axis 190 of the cutter 100. The bagging film 34 is secured between the frustoconical surfaces 54 and 164 and extends across the top surface 56 of the base 52 of the vacuum port 50 so that there is a clearance between the cutting wheels 130 and the bagging film 34. With the cutter 100 positioned as shown in FIGURE 8, the handle 140 is pressed downward in the direction of the arrow.

[0048] Downward movement of the handle 140 moves the cutting assembly 110 downward to drive the cutting wheels 130 through the bagging film 34. The downward movement of the cutting assembly 110 continues until the cutting wheels 130 contact the top surface 56 of the base 52, as shown in FIGURE 9. With the cutting wheels 130 in contact with the top surface, the user rotates the handle about axis 190, as indicated by the arrows. Rotating the handle 140 rotates the cutting assembly 1 10 about the central axis 190.

[0049] As the cutting assembly 110 rotates, each cutting wheel 130 is driven about an arcuate path having a constant radius. The number and relative position of the cutting wheels 130 are such that the cutting wheels cooperate to make a complete circular cut through the bagging film 34 by rotating the handle 120°. In some embodiments, the cutting assembly 110 includes more than three cutting wheels, and a complete circular cut through the bagging film 34 is achieved by rotating the handle less than 120°. In some embodiments, the cutting assembly 110 includes fewer than three cutting wheels, and a complete circular cut through the bagging film 34 is achieved by rotating the handle greater than 120°.

[0050] Referring now to FIGURE 10, with the circular cut 202 through the bagging film 34 completed, the cutter 100 is lifted away from the layup 20, as indicated by the arrow. The scrap 200 of bagging film bounded by the cut 202 is removed, leaving a hole through which the threaded protrusion 70 of the fitting 64 can extend to assemble the vacuum port 50.

[0051] The cutting wheels 130 are positioned such that the circular cut 202 is approximately centered between the outer edge of the top surface 56 of the base 52 and the outer edge of the threaded aperture 62 of the base. In some embodiments, the circular cut 202 is closer to or farther from the edge of the top surface 56 of the base 52.

[0052] Embodiments of the cutter 100 provide uniform, predicable holes through the bagging film 34 that ensure that a sufficient amount of the bagging film will be clamped between the base 52 and the fitting 64 of the vacuum port 50 to prevent leaks. Further, the use of multiple circular cutting wheels 130 increases the useful life of the cutting elements as compared to known cutters. The circumferential cutting edges 132 of the cutting wheels 130 results in each portion of the cutting edge cutting less material than a traditional fixed blade for a given circular cut. Further, utilizing multiple cutting wheels 130 proportionally reduces the cutting performed by a given cutting element. As a result, the disclosed cutting wheels 130 remain sharp and effective for longer intervals than known cutters. Moreover, the cutting assembly 110 can be easily removed from the housing 150 for easy replacement of the cutting wheels 130.

[0053] Embodiments of the disclosed cutter 100 are suitable for providing holes through vacuum films to enable the installation of vacuum ports in composite part layups. It will be appreciated that the cutters are not limited to a particular type of composite part or manufacturing method. In this regard, embodiments of the disclosed cutter may besuitable for use with any type of part or process that utilizes a vacuum film with a vacuum port mounted thereto.

[0054] The detailed description set forth above in connection with the appended drawings, where like numerals reference like elements, are intended as a description of various embodiments of the present disclosure and are not intended to represent the only embodiments. Each embodiment described in this disclosure is provided merely as an example or illustration and should not be construed as preferred or advantageous over other embodiments. The illustrative examples provided herein are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Similarly, any steps described herein may be interchangeable with other steps, or combinations of steps, in order to achieve the same or substantially similar result.

[0055] In the foregoing description, specific details are set forth to provide a thorough understanding of representative embodiments of the present disclosure. It will be apparent to one skilled in the art, however, that the embodiments disclosed herein may be practiced without embodying all of the specific details. In some instances, well-known process steps have not been described in detail in order not to unnecessarily obscure various aspects of the present disclosure. Further, it will be appreciated that embodiments of the present disclosure may employ any combination of features described herein. All such combinations or sub-combinations of features are within the scope of the present disclosure.

[0056] The present application may reference quantities and numbers. Unless specifically stated, such quantities and numbers are not to be considered restrictive, but exemplary of the possible quantities or numbers associated with the present application. Also, in this regard, the present application may use the term ‘'plurality’’ to reference a quantity or number. In this regard, the term “plurality” is meant to be any number that is more than one, for example, two, three, four, five, etc. The terms “about,” “approximately,” “near,” etc., mean plus or minus 5% of the stated value. For the purposes of the present disclosure, the phrase “at least one of A, B, and C,” for example, means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C), including all further possible permutations when greater than three elements are listed.

[0057] It should be noted that for purposes of this disclosure, terminology such as “upper,” “lower.” “vertical.” “horizontal.” “fore.” “aft.” “inner,” “outer.” “front,” “rear,” etc., should be construed as descriptive and not limiting the scope of the claimed subjectmatter. Further, the use of "including." “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings.

[0058] Throughout this specification, terms of art may be used. These terms are to take on their ordinary meaning in the art from which they come, unless specifically defined herein or the context of their use would clearly suggest otherwise.

[0059] The drawings in the FIGURES are not to scale. Similar elements are generally denoted by similar references in the FIGURES. For the purposes of this disclosure, the same or similar elements may bear the same references. Furthermore, the presence of reference numbers or letters in the drawings cannot be considered limiting, even when such numbers or letters are indicated in the claims.

[0060] The principles, representative embodiments, and modes of operation of the present disclosure have been described in the foregoing description. However, aspects of the present disclosure, which are intended to be protected, are not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. It will be appreciated that variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present disclosure. Accordingly, it is expressly intended that all such variations, changes, and equivalents fall within the spirit and scope of the present disclosure as claimed.

Claims

AMENDED CLAIMS received by the International Bureau on 27 November 2024 (27.11 .2024)

1. A vacuum port cutter, comprising: a housing that includes an internal cavity having an open lower end with an internal frustoconical surface formed thereon; a body at least partially disposed within the cavity and mounted for translational movement relative to the housing along a first axis and rotational movement about the first axis relative to the housing; and a cutting wheel rotatably mounted about a second axis to the base.

2. The vacuum port cutter of Claim 1 , comprising a total of three cutting wheels rotatably mounted to the base.

3. The vacuum port cutter of Claim 2, wherein the cutting wheels are positioned to be equally spaced around the first axis.

4. The vacuum port cutter of Claim 1 , wherein the frustoconical surface has a taper corresponding to a taper of a base of a vacuum port.

5. The vacuum port cutter of Claim 1 , further comprising a stem extending from the body along the first axis, the stem extending through an upper portion of the housing and having a handle mounted thereto.

6. The vacuum port cutter of Claim 5, further comprising a biasing element configured to bias the handle away from the housing.

7. The vacuum port cutter of Claim 6, wherein the biasing element is a compression spring engaging the housing and the handle.

8. The vacuum port cutter of Claim 1 , wherein the body is selectively moveable between a retracted position and an extended position.

9. The vacuum port cutter of Claim 8, further comprising a biasing element configured to bias the body toward a retracted position.

10. The vacuum port cutter of Claim 9, further comprising a stem extending from the body along the first axis, the stem extending through an upper portion of the housing and having a handle mounted thereto.

11. The vacuum port cutter of Claim 10, wherein the biasing element is a compression spring engaging the handle and the housing.

12. The vacuum port cutter of Claim 11 , wherein the stem extends through a central portion of the compression spring.

13. The vacuum port cutter of Claim 8, wherein the frustoconical surface has a taper corresponding to a taper of a base of a vacuum port.

14. The vacuum port cutter of Claim 1 , wherein the base includes a planar mounting surface, the second axis being perpendicular to the mounting surface.

15. The vacuum port cutter of Claim 14, wherein the cutting wheel is mounted to the base with a fastener, a spring being disposed between the cutting wheel and the mounting surface.

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