CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. Provisional Patent Application No.

62 /385,180, filed September 8, 2016, which is hereby incorporated by reference in its entirety herein.

BACKGROUND

Field

[0002] Various embodiments relate generally to part ejectors for ejecting work pieces from workholding clamps of part processing machines.

Description of Related Art

[0003] In part processing machines such as CNC machine centers, mills, lathes, etc., parts to be processed are conventionally automatically placed into a workholding clamp of the machine, processed, and then ejected from the clamp by a part ejector.

SUMMARY

[0004] It was discovered that conventional part ejectors can provide such high speeds and forces that they can damage delicate parts during the ejection process (e.g., by launching the part through the air so that it impacts a side of a collection bin or a head wall of the machine).

[0005] One or more non-limiting embodiments provide a part ejector with a dampener that restricts a speed at which the ejector ejects a part from a workholding clamp, thereby reducing a risk of ejection-induced damage to the part.

[0006] One or more non-limiting embodiments provide a part ejector for ejecting a part from a part processing machine. The ejector includes: a body adapted to be mounted to a part processing machine; an ejector rod coupled to the body for movement relative to the body between retracted and extended positions, the ejector rod being configured to eject a part from a workholding clamp of the part processing machine when the rod moves from its retracted position to its extended position; an actuator (e.g., a pneumatic or hydraulic actuator) configured to move the rod from its retracted position to its extended position; and a dampener configured to provide extension dampening to dampen a speed at which the actuator moves the rod from its retracted position to its extended position. [0007] According to one or more embodiments, the dampener provides more extension dampening than retraction dampening, retraction dampening being dampening of a speed at which the rod moves from its extended position to its retracted position.

[0008] According to one or more embodiments, an amount of the extension dampening is user-adjustable.

[0009] According to one or more embodiments, the dampener provides dampening over an entire extension stroke of the rod from its retracted position to its extended position.

[0010] According to one or more embodiments, the dampener includes: a dampening chamber having fluid disposed therein; a rod-driving piston connected to the rod for movement with the rod between the rod's retracted and extended positions, the rod-driving piston being slidably mounted within the dampening chamber and separating the dampening chamber into first and second sub-chambers; an extension fluid pathway fluidly connecting the first and second sub-chambers such that movement of the rod-driving piston and rod from the rod's retracted position to its extended position urges fluid to flow from the second sub-chamber into the first sub-chamber via the extension fluid pathway; and a flow-restricting orifice disposed in the extension fluid pathway and configured to dampen a speed of fluid flow through the extension fluid pathway. According to one or more of these embodiments, at least 50% of a volume of the dampening chamber is filled with an incompressible fluid.

[0011] According to one or more of these embodiments, the ejector includes an air inlet port opening into the first sub-chamber. The air inlet port is configured to fluidly connect a source of compressed gas to the first sub-chamber.

[0012] According to one or more embodiments, a size of the orifice is user- adjustable.

[0013] According to one or more embodiments, the dampener comprises an orifice obstruction that is movable to selectively change a size of the orifice so as to selectively change an amount of extension dampening provided by the dampener.

[0014] According to one or more embodiments, the orifice obstruction is accessible to a user via an open end of the rod.

[0015] According to one or more embodiments, the extension fluid pathway extends through the rod-driving piston; the dampener includes an adjustment screw operatively connected to the orifice obstruction and threadingly connected to the piston so that pivotal movement of the adjustment screw moves the orifice obstruction and changes a size of the orifice; and the adjustment screw is accessible via an open axial end of the rod.

[0016] According to one or more of these embodiments: the ejector rod is linearly movable along an ejector rod axis between its retracted and extended positions; and rotation of the adjustment screw moves the adjustment screw along the ejector rod axis.

[0017] According to one or more embodiments, the rod is partially disposed within the second sub-chamber such that the second sub-chamber has a smaller effective cross-sectional area than the first sub -chamber.

[0018] According to one or more embodiments: pressurization of the first sub- chamber urges the rod-driving piston to move the rod toward its extended position; and the actuator is configured to pressurize the first sub -chamber so as to move the rod into the rod's extended position.

[0019] According to one or more embodiments, the part ejector also includes: a retraction fluid pathway fluidly connecting the first and second sub-chambers such that movement of the rod from the rod's extended position to its retracted position urges fluid to flow from the first sub-chamber into the second sub-chamber via the retraction fluid pathway; and a check valve disposed in the retraction fluid pathway and oriented to permit fluid to flow through the retraction fluid pathway from the first sub -chamber into the second sub-chamber while discouraging fluid from flowing through the retraction fluid pathway from the second sub-chamber into the first sub-chamber. According to one or more embodiments, the retraction fluid pathway extends through the rod-driving piston.

[0020] According to one or more embodiments, the actuator includes: a gas chamber having an air inlet port configured to be selectively connected to a source of compressed gas; and a movable gas piston separating the gas chamber from the dampening chamber and being movable in (1) an extension direction that increases a volume of the gas chamber while pressurizing the dampening chamber, and (2) a retraction direction that decreases a volume of the gas chamber.

[0021] One or more embodiments provide a part processing machine (e.g., a lathe, milling machine, machine center, CNC center, etc.) that includes such a part ejector. According to one or more embodiments, the part processing machine includes: a base; a spindle mounted to the base for rotation relative to the base; and a

workholding clamp mounted for rotation with the spindle relative to the base. The part ejector is mounted to the base and configured to eject a part from the workholding clamp when the rod moves from its retracted position to its extended position.

[0022] According to one or more embodiments: the dampener comprises a manually adjustable adjustment screw that adjusts an amount of the extension dampening; and the adjustment screw is accessible to a user through an axial end of the clamp.

[0023] According to one or more embodiments, when the rod is in its retracted position, the rod does not interfere with a part being positioned in an clampable position relative to the clamp.

[0024] One or more of these and/or other aspects of various embodiments of the present invention, as well as the methods of operation and functions of the related elements of structure and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. In one embodiment, the structural components illustrated herein are drawn to scale. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention. In addition, it should be appreciated that structural features shown or described in any one embodiment herein can be used in other embodiments as well. As used in the specification and in the claims, the singular form of "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] For a better understanding of various embodiments as well as other features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:

[0026] FIG. 1 is an end view of a part processing machine according to one or more embodiments; [0027] FIG. 2 is a cross-sectional perspective view of the machine in FIG. 1, with the cross-section taken along the line A-A in FIG. 1;

[0028] FIG. 3 is a part cross-sectional, part diagrammatic view of the machine in

FIG. 1, with the cross-section taken along the line A-A in FIG. 1;

[0029] FIG. 4 is a cross-sectional view of a part ejector and workholding clamp of the machine in FIG. 1;

[0030] FIG. 5 is a cross-sectional view of the part ejector of FIG. 4, shown in a retracted position;

[0031] FIG. 6 is a cross-sectional view of the part ejector of FIG. 4, shown in an extended position;

[0032] FIG. 7 is a front end view of a rod-driving piston and ejection rod of the part ejector of FIG. 4;

[0033] FIG. 8 is a cross-sectional view of the part ejector of FIG. 4 taken along the line B-B in FIG. 7 and shown during extension of an ejector rod of the part ejector;

[0034] FIG. 9 is a cross-sectional view of the part ejector of FIG. 4 taken along the line B-B in FIG. 7 and shown during retraction of an ejector rod of the part ejector;

[0035] FIG. 10 is a cross-sectional perspective view of the part ejector of FIG. 4, shown in a retracted position; and

[0036] FIG. 11 is a cross-sectional view of a part ejector of according to an alternative embodiment.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0037] FIGS. 1-3 illustrate a part processing machine 10 according to one or more embodiments. The part processing machine 10 may comprise any type of machine that holds and processes parts (e.g., a lathe, milling machine, machine center, CNC center, etc.). For example, the part processing machine 10 may comprise a rotary table, as shown and described in PCT Publication No. WO 2008/024962, the entire contents of which are hereby incorporated by reference. The machine 10 comprises a base 20, a motor-driven spindle 30 mounted to the base 20 for motor-driven rotation relative to the base 20, a workholding clamp 40 mounted for rotation with the spindle 30, and a part ejector 100 mounted to the base 20 and configured to eject a part from the workholding clamp 40. In the illustrated machine 10, the base 20 comprises a machine headstock that mounts to a remainder of the machine 10. The machine 10 may additionally include part processing structures (e.g., tools for cutting, lathing, milling, grinding, sanding, polishing, etc.).

[0038] The workholding clamp 40 is configured to selectively clamp a part to be processed to the spindle 30 for processing. As shown in FIG. 4, the illustrated clamp 40 is an outside-diameter clamp, but may alternatively comprise an inside-diameter clamp. The illustrated clamp 40 is a collet-based clamp. However, the clamp 40 may

alternatively comprise any other type of clamp that is suitable for clamping a part to the spindle 30 for processing (e.g., a jaw chuck, a suction clamp, etc.). The clamp 40 is actuated between clamping and released positions via a suitable actuator (e.g., an automated hydraulic or pneumatic drawbar). When the clamp 40 is in the clamping position and a part is in a clampable position relative to the clamp 40, the clamp 40 firmly clamps the part to the spindle 30 for processing. In the released position of the clamp 40, a part may be placed into and removed from the clampable position.

[0039] The part ejector 100 includes an ejector rod 280, a pneumatic actuator 80, and a hydraulic dampener 90. The actuator 80 is configured to drive the rod 280 from a retracted position (shown in FIG. 5) to an extended position (shown in FIGS. 4, 6) to forcibly eject a part from the clamp 40.

[0040] As shown in FIG. 4, the part ejector 100 comprises a tubular body 110 that threadingly mounts to an adapter 120, which, in turn, threadingly mounts to the workholding clamp 40 to rigidly secure the part ejector 100 to the clamp 40. The part ejector 100 is therefore mounted to the base 10 via the workholding clamp 40, which is mounted to the spindle 30, which is mounted to the base 20. In the illustrated embodiment, the part ejector 100 rotates with the spindle 30 and clamp 40 relative to the base 20. However, according to alternative embodiments, the part ejector 100 may mount directly to the base so that the spindle 30 and workholding clamp 40 rotate relative to the base 20 and part ejector 100.

[0041] Hereinafter, the structure of the part ejector 100 is described with reference to FIGS. 5-10.

[0042] Hereinafter, the actuator 80 is described with reference to FIGS. 4-6. As shown in FIGS. 5-6, the longitudinal ends of the tubular body 110 are capped by rear and front end caps 130, 140 that threadingly connect to the body 110 and include sealing 0-rings 150 (or other seals) to seal the interfaces between the body 110 and the caps 130, 140. A gas piston 160 is disposed within the tubular body 110 for linear movement along a longitudinal axis 170 of the part ejector 100 between a retracted position (shown in FIG. 5) and an extended position (shown in FIG. 6). The gas piston 160 includes an 0-ring seal 180 to seal the sliding interface between the body 110 and gas piston 160. The gas piston 160 separates a gas chamber 190 within the body 110 from a dampening chamber 200 within the body 110. The dampening chamber 200 is sealed and is filled with a fixed volume of incompressible fluid (e.g., a liquid such as oil, water, mineral oil, etc.). According to various embodiments, the incompressible fluid occupies at least 30, 40, 50, 60, 70, 80, 85, 90, 95, 96, 97, 98, 99, and/or 99.5% by volume of a volume of the dampening chamber 200. According to one or more embodiments, a remaining volume of the dampening chamber 200 is occupied by a compressible fluid (e.g., air bubbles). Alternatively, the dampening chamber 200 could be filled with a compressible fluid (e.g., air or another gas) such that the dampener 100 is a pneumatic dampener. In such an alternative embodiment, compressible fluid occupies at least 30, 40, 50, 60, 70, 80, 85, 90, 95, 96, 97, 98, 99, and/or 99.5% by volume of a volume of the dampening chamber 200 when the pressure within the chamber 200 is atmospheric pressure (with a remaining volume of the dampening chamber 200 being occupied by another fluid such as a lubricating oil or other incompressible fluid). The piston 160 is movable in (1) an extension direction that increases a volume of the gas chamber 190 while pressurizing the dampening chamber 200, and (2) a retraction direction that decreases a volume of the gas chamber 190.

[0043] As shown in FIGS. 4-5, an air inlet/outlet port 220 (e.g., a Schrader valve) extends through the rear cap 130 so as to be in fluid communication with the gas chamber 190. As shown in FIG. 4, a source 230 of pressurized gas (e.g., compressed air supply pipe or tank or compressor) connects to the air inlet port 220 by way of a part ejector control valve 240 and fluid passage 250 to selectively pressurize the gas chamber 190. According to various embodiments, the valve 240 has two positions: (1) a first position that fluidly connects the source 230 of pressurized gas to the port 220 to pressurize the gas chamber 190 and operate the part ejector 100, and (2) a second position that fluidly connects the port 220 to an ambient atmosphere to permit gas to vent from the gas chamber 190 into the ambient atmosphere. The valve 240 may comprise an automatic valve that is controlled by the machine 10. Alternatively, the valve 240 may comprise a manually controlled valve that may be operated by a user of the machine 10 to operate the ejector 100. [0044] If the part ejector 100 rotates relative to the base 20, the fluid passage

250 may comprise a rotational fluid coupling that permits rotation of the end of the passage 250 that connects to the port 220, while allowing the end of the passage 250 that connects to the valve 240 and/or source 230 of gas to remain stationary.

[0045] As shown in FIGS. 5-6, the ejector rod 280 slidingly extends through a hole 140A in the front end cap 140. An 0-ring 290 or other seal seals the interface between the rod 280 and front end cap 140. The ejector rod 280 is linearly slidable along the axis 170 relative to the body 110 and end cap 140 between a retracted position (shown in FIG. 5) and an extended position (shown in FIGS. 3, 4, 6). The ejector rod 280 is configured to eject a part from the workholding clamp 40 when the rod 280 moves from its retracted position to its extended position. As shown in FIG. 4, the ejector rod 280 may connect to an enlarged front ejector head 280B that is configured to contact and push a part from the clamp 40 when the rod 280 moves into its extended position. Thus, the rod 280 may eject a part through direct contact with the part or through indirect contact (e.g., by way of an additional structure such as the ejector head 280B). When the rod 280 is in its retracted position, the rod 280 does not interfere with a part being positioned in an clampable position relative to the clamp 40.

[0046] In the illustrated embodiment, the ejector rod 280 has a tubular shape with a circular cross-section. However, according to alternative embodiments, the rod 280 may have any other suitable shape (e.g., a solid or hollow rod with a circular, square, oval, or polygonal cross-section).

[0047] Hereinafter, the hydraulic dampener 90 of the part ejector 100 is described with reference to FIGS. 5-10. As shown in FIGS. 5-6, a rod-driving piston 300 of the hydraulic dampener 90 connects to the rod 280 (e.g., via a threaded connection) and slides with the rod 280 along the axis 170 relative to the body 100 as the rod 280 and piston 300 move between their mutual retracted and extended positions. The piston 300 includes an 0-ring 310 (or other seal) that seals a sliding interface between the piston 300 and the body 110. The piston 300 is slidably mounted within the dampening chamber 200 and separates the chamber 200 into first and second sub- chambers 200A, 200B.

[0048] As shown in FIG. 8, the piston 300 comprises two pieces 300A, 300B that are axially fastened together, for example by bolts 320 (shown in FIG. 7) or other fasteners. Alternatively, a body of the piston 300 may comprise a single piece. [0049] As shown in FIGS. 5-6, the rod 280 extends axially through the second sub-chamber 200B, but not through the first sub -chamber 200A. As a result, the second sub-chamber 200B has a smaller effective cross-sectional area in a direction

perpendicular to the axis 170 than the first sub-chamber 200A.

[0050] As shown in FIG. 8, an extension fluid pathway 330 extends through the piston 300 from the second sub-chamber 200B, through one or more holes 340 (also shown in FIG. 7) in the chamber-200B-side of the piston 300, through an annular cavity 350 in the piston 300 formed between the piston parts 300A, 300B, through a flow- restricting orifice 360, and into the first sub -chamber 200A. Movement of the rod 280 and piston 300 from the retracted position (shown in FIG. 5) to the extended position (shown in FIG. 6) reduces a volume of the second sub-chamber 200B and increases a volume of the first sub-chamber 200A, which forces hydraulic fluid through the extension fluid pathway 330 from the second sub-chamber 200B into the first sub- chamber. The orifice 360 in the extension fluid pathway restricts hydraulic fluid flow therethrough so as to provide extension dampening to dampen a speed at which the rod 280 moves from its retracted position to its extended position. According to various non-limiting embodiments, the hydraulic dampener 90 provides dampening over an entire extension stroke of the rod 280 from its retracted position (shown in FIGS. 5, 10) to its extended position (shown in FIGS. 3, 4, 6).

[0051] As best shown in FIG. 8, the orifice 360 has an annular tapered/conical shape and is formed between (1) a cone-shaped hole 370 in the piston piece 300A that extends from the cavity 350 to the first sub-chamber 200A, and (2) a cone-shaped end 380A of an adjustment screw 380. The cone-shaped end 380A forms an orifice obstruction whose position determines a size of the orifice 360. As shown in FIGS. 5-6, the adjustment screw 380 is disposed within an axially extending opening 280A in the rod 280, and threadingly connects to the rod 280. Rotation of the screw 380 relative to the rod 280 about the axis 170 moves the screw 380 linearly along the axis 170 relative to the rod 280 to selectively (1) move the screw 380 and cone-shaped end 380A toward the hole 370 (to the left as shown in FIGS. 4-6 & 8-9) to decrease a cross-sectional area of the orifice 360 and increase the extension dampening effect of the hydraulic dampener 90, or (2) move the screw 380 and cone-shaped end 380A away from the hole 370 (to the right as shown in FIGS. 4-6 & 8-9) to increase a cross-sectional area of the orifice 360 and decrease the extension dampening effect of the hydraulic dampener 90.

[0052] As shown in FIGS. 4 and 10, a manually-accessible head 380B (e.g., a hex- head, flat-head, Philips head, Alan head, etc.) of the screw 380 is user-accessible and adjustable from a front, longitudinal end of the part ejector 100 via the opening 280A in the front axial end of the rod 280. As a result, according to various non-limiting embodiments, the adjustment screw 380 is accessible by a user for adjustment through an axial end of the clamp 40 (the right side as shown in FIGS. 3-4). A removable plug may be inserted into the opening 280A to discourage debris from entering the opening 280A when the user is not adjusting the dampener 90. As shown in FIG. 8, an 0-ring seal 390 seals a sliding/rotating interface between the screw 380 and rod 280.

[0053] As shown in FIG. 9, the hydraulic dampener 100 includes a retraction fluid pathway 500 fluidly connecting the first and second sub-chambers 200A, 200B such that movement of the rod 280 and piston 300 from their extended position to their retracted position urges hydraulic fluid to flow from the first sub-chamber 200A into the second sub-chamber 200B via the retraction fluid pathway 500. The pathway 500 extends from the first sub-chamber 200A through one or more check-valves 510 (e.g., 2- 8 parallel check valves 510), into the cavity 350, through the hole(s) 340, and into the second sub-chamber 200B. The check valve 510 is disposed in the retraction fluid pathway 500 and oriented to permit hydraulic fluid to flow through the retraction fluid pathway 500 from the first sub-chamber 200A into the second sub-chamber 200B while discouraging hydraulic fluid from flowing through the retraction fluid pathway 500 from the second sub-chamber 200B into the first sub-chamber 200A. The check valve 510 is shown in a closed position in FIG. 8 (during extension of the part ejector 100) and an open position in FIG. 9 (during retraction of the part ejector 100). In the illustrated embodiment, the check valve 510 comprises a ball-type check valve 510 that includes a ball 520 that is biased by a spring 530 toward a closed position to discourage or prevent fluid flow from the second sub-chamber 200B to the first sub-chamber 200A. The ball 520 and spring 530 are compressed between the piston pieces 300A, 300B when the piston pieces 300A, 300B are fastened to each other to form the check valve 510. When a pressure in the first sub-chamber 200A exceeds a pressure in the second sub-chamber 200B, the fluid in the first sub-chamber 200A pushes the ball 520 to the right, as shown in FIG. 9, to open the valve 510 and permit relatively unrestricted fluid flow from the first sub-chamber 200A into the second sub-chamber 200B. The retraction fluid pathway 500 and check valve 510 therefore reduce the dampener's retraction dampening effect (i.e., an extent to which the dampener 90 dampens a speed at which the rod 280 and piston move from their extended position to their retracted position).

[0054] The extension and retraction pathways 330, 500 cause the hydraulic dampener 90 to provide more extension dampening than retraction dampening. Thus, the dampener 90 limits an extension speed of the rod 280, while generally permitting the rod 280 to freely and quickly retract with little or no dampening effect.

[0055] In the illustrated embodiment, the fluid pathways 330, 500 extend through the piston 300. However, according to alternative embodiments, the pathway 330 and/or 500 may connect the sub-chambers 200A, 200B without passing through the piston 300 (e.g., via one or more dedicated fluid passages that connect opposite ends of the sub-chambers 200A, 200B and extend externally of the body 110).

[0056] As shown in FIG. 5, an annular ring 550 (or other blocking structure) is disposed in the chamber 200 between the pistons 160, 300. The ring 550 threadingly mounts to the body 110 to prevent the ring 550 from moving axially within the chamber 200. The ring 550 limits an extent of retracting movement of the piston 300 and rod 280 so that the rod 280 does not move entirely into the chamber 200 (thereby unsealing the hole 140A and permitting hydraulic fluid to leak out through the hole 140A). According to various embodiments, the piston 300 contacts the ring 550 when the piston 300 and rod 280 move into their retracted position. As shown in FIG. 5, this provides a maximum stroke length 560. According to one or more embodiments, the maximum stroke length of the ejector 100 is (1) at least 0.25, 0.5, 0.75, 1, 2, 3, and/or 4 inches, (2) less than 10, 9, 8, 7, 6, 5, 4, 3, 2, and/or 1 inch, and/or (3) between any two of these lengths (e.g., between 0.25 and 10 inches, between 0.5 and 8 inches, between 1 and 7 inches, about 4.4 inches). According to other embodiments, the piston 300 does not contact the ring 550 even when the piston 300 and rod 280 move into their retracted position.

[0057] According to various embodiments, the retracted position of the piston

300 and rod 280 comprises a position in which the part ejector 100 does not interfere with placement of part in a desired clampable position relative to the clamp 40, regardless of whether the piston 300 and/or rod 280 are capable of further

rearward/retracting movement (to the left as shown in FIGS. 5-6). [0058] Hereinafter, operation of the machine 10 is described. With the rod 280 in its extended position and the clamp 40 in its released position, a part to be processed is moved into the clampable position (e.g., by a pick & place tool of the machine 100). Movement of the part into the clampable position causes the part to push the rod 280 from its extended position into its retracted position. As shown in FIG. 9, this retraction of the rod 280 is relatively unimpeded/undampened because the check valve 510 opens, which allows hydraulic fluid to freely flow through the retraction fluid pathway 500 from the first sub-chamber 200A into the second sub-chamber 200B, permitting relatively free and fast retracting movement of the rod-driving piston 300 and rod 280. This retracting movement increases an overall volume of the dampening chamber 200 as more and more of the rod 280 is disposed within the chamber 200. This increase in the overall volume of the dampening chamber 200, in turn, pushes the gas piston 190 away from the chamber 200 (to the left as shown in FIGS. 5-6), which decreases a volume of the gas chamber 190 and forces air in the gas chamber 190 out to the ambient atmosphere via the valve 240, which is in its second/retracted position.

[0059] The clamp 40 is then moved into its clamping position (e.g., via a drawbar or other actuator) to clamp the part to the clamp 40. The part is then processed (e.g., via lathing, machining, or other processing operations). The clamp 40 is then moved into its released position so as to permit movement of the part relative to the clamp 40.

[0060] The actuator 80 of the part ejector 100 is then actuated to eject the part from the clamp 40. In particular, the valve 240 is moved into its first position, which causes compressed air to flow from the source 230 through the passageway 250 and port 220 into the gas chamber 190. This pushes the gas piston 160 toward the dampening chamber 200, which pressurizes the chamber 200. Pressure in the chamber 200 (specifically the sub-chamber 200A) causes the rod-driving piston 300 and rod 280 to move from their retracted position to their extended position. This extending motion of the piston 300 and rod 280 causes hydraulic fluid to flow through the extension pathway 330 from the second sub-chamber 200B to the first sub-chamber 200A. The orifice 360 restricts a volumetric speed of such fluid flow through the extension pathway 330, which restricts a speed at which the rod 280 extends. Little or no hydraulic fluid flows through the retraction pathway 500 because the closed check valve 510 discourages such flow from the second sub-chamber 200B to the first sub- chamber 200A via the retraction pathway 500, as shown in FIG. 8. As the rod 280 moves toward and into its extended position, the rod 280 (and specifically the enlarged head 28 OB thereof) contacts the part and pushes the part out of the clamp 40. The part falls into a part collection bin (not shown) disposed in front of and below the clamp 40. The dampener 90 thus slows the extension speed of the rod 280 so that the rod 280 gently ejects the part from the clamp 40 and reduces a risk of ejection-induced damage to a delicate part.

[0061] A user can manually adjust the extension dampening of the hydraulic dampener 90 by accessing the head 380B of the adjustment screw 380 via a front axial end of the clamp 40 with an appropriate tool (e.g., a screw driver) and rotating the screw 380 clockwise or counterclockwise to increase or decrease a size of the orifice, and thereby decrease or increase a speed-dampening effect of the dampener 90 to speed up or slow down the extension speed of the rod 280.

[0062] A force being applied by the rod 280 to the part during ejection may be controlled by controlling a pressure of the compressed air being supplied to the gas chamber 190. To do so, the valve 240 may comprise a pressure-regulating valve 240.

[0063] In the illustrated embodiment, the actuator 80 comprises a pneumatic actuator 80 that relies entirely on pneumatic force on the piston 160 to extend the rod 280 from its retracted position to its extended position. In the illustrated embodiment, extension of the rod 280 is not aided by a spring. However, under additional and/or alternative embodiments, extension of the rod 280 may be spring-assisted (or spring- based in its entirety). For example, according to one or more alternative embodiments, the actuator 80 is non-pneumatic, and comprises compression spring disposed in the openly vented gas chamber 190. The spring extends between the end cap 130 and the piston 160 to bias the piston 160 toward the chamber 200 (to the right as shown in FIGS. 4-6 & 8-9). In such an embodiment, movement of the part into the clampable position may compress the actuator spring as the part forces the rod 280 to move into its retracted position. When the clamp 40 is then released after the part is processed, the spring automatically pushes the piston 160, which pressurizes the chamber 200 and causes the rod 280 to move into its extended position, which ejects the part. In such a spring-based actuator, the actuator is not pneumatically driven.

[0064] According to one more alternative embodiments, the ejector rod 280 is spring-biased by a retraction spring of the actuator 80 toward its retracted position (e.g., via a compression spring disposed in the second sub-chamber 200B and extending between the end cap 140 and piston 300). Use of the actuator 80 to inject compressed gas into the chamber 190 extends the rod 280 and compresses the retraction spring. When the actuator 80 is turned off so that pressure in the chamber 190 returns to atmospheric pressure, the retraction spring pushes the piston 300 and rod back to their retracted positions.

[0065] The illustrated part ejector 100 is a hybrid air/hydraulic part ejector 100.

However, according to one or more alternative embodiments, the part ejector is fully pneumatic. In one or more embodiments, the illustrated part ejector 100 is modified by filling the dampening chamber 200 with a compressible gas such as air. As shown in FIG. 11, a part ejector 1100 may replace the part ejector 100 discussed above in the machine 10. The part ejector 1100 is generally similar or identical to the part ejector 100 except that the gas piston 160 of the ejector 100 is eliminated, which results in the merger of the gas chamber 190 and first sub-chamber 200A into a single combined first sub-chamber 1200A that is separated from the second sub-chamber 200B by the piston 300. Thus, the air inlet port 220 leads directly into the first sub-chamber 1200A. The part ejector 100 may be further modified by reducing a size of the orifice 360 to account for the reduced viscosity of air relative to hydraulic fluids such as oil, and/or providing for finer adjustment of a size of the orifice 360 (e.g., by reducing a diameter of the cone- shaped orifice 360; providing finer threads in the threaded connection between the screw 380 and rod 280; reducing an angle formed between the cone-shape of the orifice 360 and the axis 170). The check valves 510 may also be appropriately modified to operate with air as the working fluid.

[0066] According to various alternative embodiments, the part ejector comprises a hydraulic actuator and dampener that both rely on incompressible fluids. For example, the ejector 1100 illustrated in FIG. 11 can be filled with an incompressible fluid just like the above-discussed chamber 200, or the ejector 100's gas chamber 190 can be filled with an incompressible fluid. The source of compressed gas 230 can be replaced with a source of pressurized incompressible fluid (e.g., a liquid such as oil, water, mineral oil, etc.).

[0067] The foregoing illustrated embodiments are provided to illustrate the structural and functional principles of various embodiments and are not intended to be limiting. To the contrary, the principles of the present invention are intended to encompass any and all changes, alterations and/or substitutions thereof (e alterations within the spirit and scope of the following claims).