The present invention relates to assemblies for providing a surface finish and, more particularly, to a honing or sanding attachment assembly for use with portable turning machines, such as clamshell lathes or journal turning lathes.
Portable turning machines, such as journal turning lathes and clamshell lathes, may be used to provide precision cuts to and for weld preparation of workpieces like large diameter pipes and shafts (e.g., pipes and shafts having outer diameters between 2 inches and 60 inches). These portable turning machines typically perform a machining operation, such as cutting and beveling, re-machining flanges, and/or machining the workpiece.
After performing these machining operations, the surface finish of the workpiece is often not desirable, typically relatively rough. For example, such machining results in a workpiece with a surface finish with an average surface roughness (i.e., Ra value) between 80 and 160 microinches. In order to achieve a better surface finish (e.g., a Ra value between 30 and 60 microinches), a burnishing tool may be used with the turning machine. However, finishes with an average surface roughness of less than 30 microinches are typically not achievable on shafts or pipes machined with a journal turning lathe or clamshell lathe.
In one independent aspect, a honing assembly for use with a turning machine to hone a workpiece may be provided. The honing assembly may generally include a housing and a honing stone supported by the housing. The honing stone is engageable with the workpiece to remove material from and improve the surface finish of the workpiece. In some constructions, the honing assembly includes multiple honing stones supported by the housing. The honing stone may be pivotable relative to the housing about a first axis and about a second axis normal to the first axis.
In another independent aspect, a honing assembly may generally include a housing and a honing stone supported by the housing and threadedly adjustable relative to the housing. In such a construction, a force applied by the honing stone on the workpiece may be adjusted by turning a threaded member. In some constructions, the honing assembly may further include a biasing member to bias the honing stone toward the workpiece.
In yet another independent aspect, a honing assembly may generally include a housing and a honing stone removably supported by the housing. In such a construction, the removed honing stone may have a first coarseness and be replaced by a honing stone having a second coarseness. The honing stone may be supported by a bracket removably coupled to the housing, for example, by a quick release pin. In another construction, the housing may be removably coupled to a housing of the turning machine.
In a further independent aspect, a turning machine for performing an operation on a workpiece may be provided. The turning machine may generally include a rotatable machine housing operable to rotate around the workpiece, and a honing attachment supported by the machine housing and including a honing stone operable to engage the workpiece to remove material. In some constructions, the honing attachment may be removed from the machine housing and replaced with another tool, such as a sanding attachment, a machining tool, a cutting tool, a burnishing tool, etc.
In another independent aspect, a method of finishing a workpiece with a honing stone may be provided. The method may generally include providing a turning machine including a rotatable machine housing, providing a honing assembly including a housing and a honing stone supported by the housing, supporting the honing assembly on the machine housing, engaging the honing stone against an outer surface of the workpiece, and rotating the machine housing and the honing assembly relative to the workpiece to remove material from the workpiece.
In yet another independent aspect, a sanding assembly for use with a turning machine to sand a workpiece may be provided. The sanding assembly may generally include a housing, a flexible band supported by the housing, and sand paper supported by the housing, the sand paper being engageable with the workpiece to remove material from and improve the surface finish of the workpiece.
The housing may have opposite free ends, each free end supporting an end of the band and an end of the sand paper. The housing may include a first housing portion having an internal end pivotally connected to an internal end of a second housing portion. The flexible band may include a metal band. The flexible band may flex to match a diameter of the workpiece.
In a further independent aspect, a turning machine for performing an operation on a workpiece may be provided. The turning machine may generally include a rotatable machine housing operable to rotate around the workpiece, and a sanding attachment supported by the machine housing and including a flexible band supporting sand paper, the sand paper being engageable with the workpiece to remove material. In some constructions, the sanding attachment may be removed from the machine housing and replaced with another tool, such as a honing attachment, a machining tool, a cutting tool, a burnishing tool, etc.
In another independent aspect, a method of finishing a workpiece with sand paper may be provided. The method may generally include providing a turning machine including a rotatable machine housing, providing a sanding assembly including a housing, a flexible band supported by the housing, and sand paper supported by the band, supporting the sanding assembly on the machine housing, engaging the sand paper against an outer surface of the workpiece, and rotating the machine housing and the sanding assembly relative to the workpiece to remove material from the workpiece.
Other independent features and independent aspects of the invention may become apparent by consideration of the following detailed description and accompanying drawings.
Before any independent embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other independent embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
Use of “including” and “comprising” and variations thereof as used herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings.
A surface finishing assembly, such as a honing attachment assembly 10, is illustrated in
With reference to
The elongated member 30 has a first end 42 with a square shoulder 46 and a seating surface 50 and a second end 54 defining a quick-release pin receiving aperture 58. The shoulder 46 is complementary to a square portion 62 (see
The adjustment cap 38 has exterior threads 66 to engage corresponding interior threads 70 adjacent an upper end of the bore 26. The cap 38 defines a drive portion 74, such as a hexagonal shaped aperture (as illustrated) to be engaged by a complementary shaped tool (e.g., a hex key). In other constructions, the drive portion 74 may have another configuration, such as a slot, a protrusion, etc., engaged by a tool, such as a screwdriver, a wrench, etc.
As shown in
With reference to
The swivel bracket 86 has first and second portions 90, 94, each defining an axis B, C. The portions 90, 94 are angled relative to one another along the length of the swivel bracket 86 such that the axes B, C define a V-shape. In the illustrated construction, the angle between axes B, C is relatively shallow (e.g., approximately 165 degrees). The angle is generally less than 180 degrees and may be between 180 degrees and approximately 150 degrees or less.
The swivel bracket 86 has a top surface 102 and opposite side surfaces 106 extending along the portions 90, 94. The top surface 102 defines an elongated recess 110 extending centrally between portions 90, 94 and receiving the second end 54 of the elongated member 30. A quick-release pin receiving bore 114 extends through the side surfaces 106 and the elongated recess 110. The bore 114 is positioned between the portions 90, 94 and defines a swivel bracket pivot axis E transverse to and passing through a point of intersection of the axes B, C.
Each portion 90, 94 of the swivel bracket 86 defines a channel 118 to receive a honing stone 98. Each channel 118 extends through the associated portion 90, 94 transverse to its axis B, C. A honing stone 98 is received in each channel 118 oriented to extend perpendicular to the swivel bracket 86. In the illustrated embodiment, the elongated member 30 is oriented by the square shoulder 46 such that the channels 118 and, thus, the honing stone(s) 98, are oriented parallel to a longitudinal axis W of the workpiece 18 (
Each portion 90, 94 of the swivel bracket 86 further defines a pin receiving bore 122 defining a honing stone pivot axis F parallel to the axis B, C of the associated portion 90, 94. Each honing stone 98 is supported by a honing stone bracket 130 defining a cotter pin receiving aperture 134. Each aperture 134 is aligned with the corresponding bore 122 when the honing stone 98 is received in the channel 118 of the associated portion 90, 94. Each aperture 134 and bore 122 receives a cotter pin 138 to connect the honing stone 98 to the swivel bracket 86.
In the illustrated construction, each honing stone 98 is free to slightly pivot in the channel 18 about the axis F and about the cotter pin 138. Each honing stone 98 is removable for replacement by removing the corresponding cotter pin 138. The honing stones 98 may be coupled (removably or non-removably; pivotably or non-pivotably) to the swivel bracket 86 by another suitable method, such as a bolt, a fastener, adhesive, etc.
The assembly 10 further includes a quick release pin 146. When the second end 54 of the elongated member 30 is received in the recess 110, the pin 146 may be axially inserted through the bore 114 in the swivel bracket 86 and the aperture 58 in the second end 54. For replacement, substitution, repair, etc., the pin 146 allows the first honing stone subassembly 82 to be quickly disconnected from the elongated member 30 and an auxiliary or second honing stone subassembly 82a (see
With continued reference to
In other constructions, each first honing stone 98 and each second honing stone 98a has a different coarseness (i.e., grit) to provide different material removal rates and surface finishes. For example, each first honing stone 98 is 220 grit, and each second honing stone 98a is 320 grit. The honing stones 98, 98a may be standard honing stones readily available and/or purchasable.
The clamshell assembly 154 includes a stationary ring 178, a movable ring gear (not shown), and a protective shroud 182 covering the movable ring gear. The stationary ring 178 has bosses 186 with linear bearings 190 configured to receive one guide shaft 158 to support the clamshell assembly 154. The bearings 190 allow for linear travel of the clamshell assembly 154 along the guide shafts 158 (i.e., parallel to the longitudinal axis W of the workpiece 18) relative to the support rings 162. The clamshell assembly 154 is driven by a linear feed screw 194 supported by the support rings 162 for movement parallel to the longitudinal axis W of the workpiece 18.
The movable ring gear is supported on the stationary ring 178 for rotation about a center of the opening of and relative to the stationary ring 178. The movable ring gear is driven for rotation about the workpiece 18 by a drive assembly (not shown) including a motor (not shown). A tool mounting assembly 202 is connected to the movable ring gear for rotation with the movable ring gear about the center of the clamshell assembly 154.
With reference to
To mount the assembly, the housing 22 is clamped between two halves of the tool block 210 by set screws 218. The assembly 10 is oriented with the honing stones 98 adjacent the workpiece 18. The tool block 210 is supported by the support block 206 to allow the tool block 210 to slide relative to the support block 206 radially toward or away from the center of the clamshell assembly 154. Turning the radial feed screw 214 moves the tool block 210 radially relative to the support block 206.
Although not shown, in some constructions, another tool mounting assembly is attached to the movable gear ring circumferentially spaced (e.g., 180 degrees) from the first mounting assembly 202. The second mounting assembly may support another honing attachment assembly similar to the assembly 10 described above and shown in
In the illustrated construction (see
During operation of the machine 14, the workpiece 18 is first supported by the support rings 162 of the machine 14. The longitudinal axis W of the workpiece 18 is centered by adjusting the centering bolts 166 until the longitudinal axis W passes through the center of each support ring 162 and the clamshell assembly 154. The machine 14 may be used to machine (e.g., cut, bevel, otherwise machine, etc.) the workpiece 18 (i.e., the shaft) by a machining tool (not shown) mounted by the mounting assembly 202 via rotation of the movable gear ring about the workpiece 18. Alternatively, the machining operation may be omitted or may have been performed previously. As a further alternative, an intermediate operation, such as burnishing, may be performed after the machining operation.
As mentioned above, machining processes typically results in an undesirable surface finish (e.g., Ra value between 80 and 160 microinches) while burnishing may improve the surface finish to between 30 and 60 microinches. To further finish the surface of the workpiece, the honing attachment assembly 10 may be used with the machine 14.
The machine tool, if previously-used, is disconnected from the tool mounting assembly 202, and the tool block 210 supporting the honing attachment assembly 10 is connected to machine 14 by clamping the housing 22 in the tool block 210. The tool block 210 is then connected to the support block 206 of the mounting assembly 202 or may have been connected before attaching the assembly 10.
Assembly and operation of a single honing attachment assembly 10 will be described. However, it should be understood that additional honing attachment assemblies 10 will be assembled and operated in the same way.
Once the honing attachment assembly 10 is attached to machine 14, the tool block 210 and the attachment assembly 10 are fed radially toward the outer surface of the workpiece 18 by turning the feed screw 214 until the honing stone(s) 98 contact the outer surface of the workpiece 18 and the spring 34 is compressed.
The spring 34 provides a biasing force acting on the seating surface 50 of the elongated member 30, which causes the honing stone(s) 98 to be biased into contact with the outer surface of the workpiece 18. The spring 34 is compressed by an amount that determines how much force the honing stone(s) 98 exert on the workpiece 18. Construction of the swivel bracket 86 equally distributes the force between each honing stone 98.
The operator turns the adjustment cap 38 in either a clockwise or counterclockwise direction with a tool engaging the drive portion 74. Due to the threaded engagement of the cap 38 in the bore 26, turning the adjustment cap 38 (depending on the direction) either loads or unloads the spring 34 to increase or decrease the force the spring 34 applies to the seating surface 50 of the elongated member 30, thereby increasing or decreasing the force the honing stone(s) 98 apply to the outer surface of the workpiece 18.
The cap 38 may be initially adjusted to compress the spring 34 into a first condition to be pre-loaded by a specific amount such that the honing stone(s) 98 apply a first force to the workpiece. Power is supplied to the machine 14 to rotate the movable gear ring and the assembly 10 about the longitudinal axis W of the workpiece 18. As the honing stone(s) 98 rotate, contact between the honing stone(s) 98 and the outer surface of the workpiece 18 removes material and improves the surface finish of the workpiece 18 with each pass.
The honing stone(s) 98 are rotated until the average surface roughness reaches a threshold value based on the coarseness of the honing stone(s) 98 and the first force. After reaching the threshold or after a predetermined number of rotations, the clamshell assembly 154, with the honing attachment assembly 10, is fed axially along the longitudinal axis W via rotation of the linear feed screw 194 to hone a length of the workpiece 18 between the support rings 162.
After the threshold value of the average surface roughness of the outer surface is reached or after a certain number of passes, rotation and travel of the tool block 210 is stopped to allow the operator to turn the adjustment cap 38 to compress the spring 34 to a second condition, thereby increasing the force that the spring 34 applies on the swivel bracket 86. The force that the honing stone(s) 98 apply to the outer surface of the workpiece 18 is increased to a second force.
After the force is increased, rotation and travel of the tool block 210 is resumed so that the honing stone(s) 98 continue honing the outer surface of workpiece 18. These steps are repeated, slowly increasing the force that the honing stone(s) 98 apply to the outer surface of the workpiece 18 by turning the adjustment cap 38 to compress the spring 34 until a desired surface finish is achieved with the first honing stone(s) 98. Typically, this is a maximum achievable surface finish with the first honing stone(s) 98. Applying too much force initially can wear out the workpiece 18 or deflect the machine 14.
Once a desired surface finish is achieved with the first honing stone(s) 98, the first honing stone(s) 98 can be quickly substituted with the second honing stone(s) 98a to further improve the surface finish. To substitute the first honing stones 98, the quick release pin 146 is removed, allowing the first subassembly 82 including the first honing stone(s) 98 to then be removed.
The second subassembly 82a with the second honing stone(s) 98a may then be connected to the elongated member 30. Specifically, the second subassembly 82a is positioned such that the second end 54 of the elongated member 30 is received in the elongated recess 110a of the swivel bracket 86a and the bore 114a and the aperture 58 are aligned. The quick release pin 146 is then inserted to connect the second subassembly 82a.
With the second subassembly 82a connected, substantially the same operation as described above is repeated until a desired surface finish (with a further improved average surface roughness) is achieved or a threshold value is reached based on the coarseness of the second honing stones 98a. Typically, this is a maximum achievable surface finish with the second honing stone(s) 98a. If necessary, another honing stone assembly (not shown) may be used to still further improve the average surface roughness of the outer surface of the workpiece.
In the illustrated construction, the swivel bracket 86 is free to pivot about the swivel bracket pivot axis E relative to the elongated member 30 on the pin 146. In addition, each honing stone 98 is free to pivot about the corresponding honing stone pivot axis F relative to the swivel bracket 86. Due to the pivot axes E, F, the multi-stone design, and the shape of the swivel bracket 86, the honing stone(s) 98 follow the profile of the outer surface of the workpiece 18 both axially and radially.
With reference to
After repeated or prolonged use, the honing stone(s) 98 may become worn or damaged. Once significant wear or damage has occurred, the honing stone(s) 98 may be replaced. The honing stone(s) 98 may be replaced by replacing the entire subassembly 82 as described above. Alternatively or additionally, each honing stone 98 of the subassembly 82 may be individually replaced by removing the corresponding cotter pins 138 to allow the honing stones 98 to be removed from the associated channel 118. A replacement honing stone (not shown) can then be inserted into the channel 118. The cotter pin 138 can then be reinserted through the bore 122 of the swivel bracket 86 and the aperture of the replacement honing stone to pivotably secure the replacement honing stone within the channel 118.
In general, a honing attachment assembly 10 for use with a turning machine 14 may include a housing 22 supporting a honing stone 98 operable to engage a workpiece 18 to remove material. The housing 22 of the honing attachment 10 may support multiple honing stones 98. The honing stone 98 may be pivotable relative to the housing about a first pivot axis E and a second pivot axis F normal to the first pivot axis E. The honing stone 98 may be supported for threading adjustment relative to the housing 22.
Another surface finishing assembly, such as a sanding attachment assembly 310, is illustrated in
With reference to
The elongated member 330 has an end 354 defining a pin receiving aperture (not shown). The opposite end of the elongated member 330 is configured to orient and prevent the elongated member 330 from rotating relative to the housing 322.
The adjustment cap 338 and the housing 322 having complementary threads (not shown). The cap 338 defines a drive portion 374, such as a hexagonal shaped aperture (as illustrated), a slot, a protrusion, etc., to be engaged by a complementary shaped tool (e.g., a hex key, a screwdriver, a wrench, etc.). The compression spring is positioned within the bore between a seating surface of the elongated member 330 and the cap 338. The compression spring biases the second end 354 of the elongated member 330 out of a lower end of the bore opposite the cap 338.
With reference to
The housing assembly 520 includes housing portions 532a, 532b pivotably connected to the end 354 by a pivot member 536 (e.g., a quick-release pin (see
The illustrated flexible band 524 includes a thin metal band having opposite ends 552. Likewise, the sand paper 528 has opposite ends 556 and a selected surface finishing characteristic (e.g., a grit) for the finish to be achieved.
As shown in
The band 524 is flexible to match the diameter of a workpiece 18 (e.g., a shaft) having a diameter between, for example, 6 inches and 32 inches. In other constructions (not shown), the sanding assembly 310 may be engageable with workpieces of different sizes.
In the illustrated construction, the housing portions 532 are constructed to match the sanding assembly 310 to the workpiece 18. The housing portions 532 have a length of, for example, 4 inches, to accommodate the size of the workpiece 18. The illustrated curved portions 544 extends about an arc of approximately 135° and have a continuous radius of curvature of, for example, 1 inch, again to accommodate the size of the workpiece 18. In other constructions (not shown), the housing portions 532 and/or the curved portions 544 may have different constructions for different workpieces.
The assembly and operation of the sanding assembly 310 is similar to that described above with respect to the honing assembly 10. As shown in
The sanding assembly 310 may be substituted for a honing attachment, a machining tool, a cutting tool, a burnishing tool, etc., in the turning tool 14. In contrast to a honing assembly, the sanding assembly 310 does not require honing oil.
In general, a sanding attachment assembly 310 for use with a turning machine 14 may include a housing 322 supporting sand paper 528 (as illustrated, through a housing assembly 520 and a flexible band 524) operable to engage a workpiece 18 to remove material. The housing assembly 520, along with the band 524 and the sand paper 528, may be pivotable relative to the housing 322 about a pivot axis E. The housing assembly 520, along with the band 524 and the sand paper 528, may be supported for threading adjustment relative to the housing 322.
Although illustrated in connection with the machine 14, such as a journal turning lathe, the surface finishing assembly 10, 210 may be used with other turning machines, such as clamshell lathes, or different sized turning machines.
One or more independent features and/or independent advantages of the invention may be set forth in the claims.
The present application claims priority to co-pending U.S. Provisional Patent Application No. 62/364,085, filed Jul. 19, 2016, the entire contents of which is hereby incorporated by reference.
Number | Date | Country | |
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62364085 | Jul 2016 | US |