Pipe grooving device

Abstract

A tube grooving device with multiple geared cams uses synchronizing gears, each meshing with two of the geared cams to synchronize the rotation of the cams of the tube element for forming a groove. The position of the groove relative to the end of the tube is controlled by a stop body incorporating a plate mounting ring that engages and disengages with a tube stop surface on one or more of the cams to restrict or allow cam rotation. The tube stop body is positioned within a cup receiving the tube element. This cup restricts flaring at the tube end and limits the tendency for the tube to become out of round during the grooving process. The device is mounted on a power chuck that rotates the tube element.

Description

[0001] Cross-reference to related applications

[0002] This application is an international application of U.S. Patent Application No. 17 / 030,418, filed on September 24, 2020, and claims the benefit of priority to that U.S. Patent Application, the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to an apparatus for cold-working tube components. Background Technology

[0004] Cold working of tubular components (e.g., imprinting circumferential grooves in the tubular component to receive mechanical tubular connectors) is advantageously accomplished using a roller grooving machine having an inner roller that engages the inner surface of the tubular component and an outer roller opposite the inner roller that simultaneously engages the outer surface of the tubular component. As the tubular component is normally rotated about its longitudinal axis by driving the inner roller, the outer roller is gradually forced toward the inner roller. The roller has a surface profile that is imprinted onto the circumference of the tubular component as it rotates, thereby forming circumferential grooves.

[0005] Various challenges exist in cold-working tubular components to the required precision within desired tolerances. The most pressing is the difficulty associated with producing a groove of the desired radius (measured from the center of the tubular component bore to the bottom of the groove) within a desired tolerance range at a desired distance from the end of the tubular component. These considerations have led to complex prior art devices, which, for example, require actuators to force the rollers into contact with the tubular component and require an operator capable of adjusting the roller stroke to achieve the desired groove radius. Furthermore, prior art roller grooving machines have low productivity, typically requiring multiple passes of the tubular component to obtain a completed circumferential groove. Clearly, there is a need for devices (e.g., those using cams to cold-work tubular components) that are simple yet produce results more quickly with less operator involvement. Summary of the Invention

[0006] This invention relates to an apparatus for cold-working tubular elements. In an exemplary embodiment, the apparatus includes a housing. A plurality of cam gears are mounted within the housing. Each of the cam gears is rotatable about a corresponding one of a plurality of first axes of rotation. The first axes of rotation are parallel to each other. The cam gears are positioned about a central space for receiving the tubular element. A plurality of cam bodies are mounted such that each cam body is located on a corresponding one of the cam gears. A plurality of cam surfaces are mounted such that each of the cam surfaces extends about a corresponding one of the cam bodies and is capable of engaging with the tubular element received in the central space. In this example, each of the cam surfaces includes a discontinuity and a region with an increased radius. Each of the radii is measured from a corresponding one of the first axes of rotation.

[0007] A traction surface extends around at least one of the cam bodies. In this example, the traction surface includes a plurality of protrusions extending outward from the at least one cam body. The traction surface has a gap therein. This gap is axially aligned with a discontinuity of the one cam surface surrounding the at least one cam body. An engagement assembly is positioned within a central space. When a tubular element is inserted into the central space, the tubular element contacts the engagement assembly. A plurality of synchronizing gears are mounted within a housing. Each of the synchronizing gears is rotatable about a corresponding one of a plurality of second rotation axes. The second rotation axes are parallel to the first rotation axis. In this example, each of the synchronizing gears meshes with two of the cam gears. As an example, each radius of each cam surface is measured from the corresponding first rotation axis of the corresponding cam gear. In the example embodiment, the number of synchronizing gears is one less than the number of cam gears. The example embodiment may include up to five cam gears. Furthermore, as an example, the device according to the invention may include up to four synchronizing gears.

[0008] In an example embodiment, the engagement assembly includes a cup. The cup surrounds a central axis and defines an opening for receiving a tube element when it is inserted into a central space. Furthermore, as an example, the cup includes an inner surface having a first diameter at the opening and a second diameter distal to the opening. In this example, the first diameter is larger than the second diameter. In a specific example, the inner surface is tapered. The example device according to the invention may also include a pipe stop body positioned within the cup. The pipe stop body is movable relative to the cup along the central axis. In this example, the cup is movable relative to a cam body along the central axis.

[0009] The example device may also include a ring mounted on a tube stop body and concentric with a central axis. A first cam stop surface extends from one of the cam bodies. The tube stop body is movable relative to the cam body between a first position and a second position, in which the ring can engage the first cam stop surface to restrict rotation of the cam body, and in the second position, the ring cannot engage the first cam stop surface to allow rotation of the cam body. In the example embodiment, the first cam stop surface is positioned adjacent to a discontinuity of the cam surface on the cam body. The example device may also include a rib extending from the cam body. The rib is positioned adjacent to the cam surface on the cam body and extends around a portion of the cam body. In this example, the first cam stop surface is positioned on a first end of the rib.

[0010] The example device may further include a second cam stop surface positioned on a second end of the rib. The second cam stop surface extends from the cam body. The second cam stop surface is positioned spaced apart from the first cam stop surface. In the example embodiment, at least one of the first and second cam stop surfaces has a concave curvature. Furthermore, as an example, a stop spring may act on the tube stop body to bias the tube stop body toward the opening of the cup. Also as an example, a cup spring acting on the cup is used to bias the cup toward the tube stop body. In the example embodiment, the tube stop body includes a plate capable of engaging with a tubular element received within a central space. A plurality of legs extend from the plate. A ring is attached to the legs. The ring is arranged coaxially with a central axis. The cup includes a plurality of slots extending axially along the central axis. In this example, the legs extend through the slots.

[0011] Example embodiments may also include a shaft positioned coaxially with a central axis. Cup and tube stop bodies surround the shaft. Furthermore, as an example, each of the cam surfaces may include a region with a constant radius positioned adjacent to a corresponding discontinuity in the cam body. Example embodiments may include multiple traction surfaces. Each of the traction surfaces extends around a corresponding one in the cam body. Example embodiments may also include multiple first cam stop surfaces. Each of the first cam stop surfaces is positioned adjacent to a corresponding discontinuity in one of the cam surfaces on each of the cam bodies. Example embodiments may also include multiple ribs. Each rib extends from a corresponding one in the cam body. The rib extends around a portion of the cam body. Each first stop surface is positioned at the end of each of the ribs. As an example, traction surfaces are positioned on the cam body at intervals from cam surfaces extending around the cam body. In example embodiments, the traction surfaces have a constant radius measured from a first axis of rotation of the cam body. Furthermore, as an example, the cam surface on the cam body is positioned between the gear and the traction surface on the cam body. In another example, the cam surface on the cam body is positioned adjacent to the traction surface on the cam body. Furthermore, as an example, the first cam stop surface is positioned between the cam surface on the cam body and the gear.

[0012] An exemplary embodiment of the device according to the invention may further include a first actuating surface positioned on a first of a plurality of cam bodies. The first actuating surface is offset from a first axis of rotation about which the first cam body rotates. An actuator is movably mounted on a housing. The actuator is movable to engage with the first actuating surface for causing the first cam body to rotate about the first axis of rotation. In an exemplary embodiment, the actuator includes a first lever pivotally mounted on the housing. The first lever has a drive surface that engages with the first actuating surface for causing the first cam body to rotate about the first axis. A second actuating surface may be positioned on a second of a plurality of cam bodies. The second actuating surface is offset from a second axis of rotation about which the second cam body rotates. An overtravel stop is movably mounted on the housing. The overtravel stop is movable to engage with a second actuating surface for stopping the rotation of the second cam body about the second axis of rotation. In an example embodiment, the overtravel stop includes a second rod mounted on the housing for pivoting movement about a pivot axis. A hook is mounted on the second rod and positioned on one side of the pivot axis. The hook is capable of engaging a second actuating surface. A spur is mounted on the second rod on the opposite side of the pivot axis. A first rod is movable to engage the spur for pivoting the second rod to disengage the hook from the second actuating surface when the first rod is moved to engage the first actuating surface. A return spring acts between the housing and the second rod to bias the hook into engagement with the second actuating surface.

[0013] The example embodiment also includes a chuck for receiving tube elements. The chuck is rotatable about a chuck axis. The chuck axis is arranged coaxially with a central axis. A housing is pivotally and axially slidably mounted near the chuck. In this example, a motor engages with the chuck to rotate the chuck about its axis.

[0014] The invention also includes an example apparatus for cold-working tube elements, comprising a housing. A plurality of cam gears are mounted within the housing. Each of the cam gears is rotatable about a corresponding one of a plurality of first axes of rotation. The first axes of rotation are parallel to each other. The cam gears are positioned about a central axis surrounded by a central space for receiving the tube element. The example includes a plurality of cam bodies, each mounted on a corresponding one of the cam gears. A plurality of cam surfaces each extend about a corresponding one of the cam bodies and are capable of engaging with the tube element received in the central space. Each of the cam surfaces includes a discontinuity and a region of increased radius. A first cam stop surface extends from one of the cam bodies. A tube stop body is positioned within the central space. The tube stop body is capable of engaging with the tube element received in the central space. The tube stop body is movable along the central axis relative to the cam body between a first position and a second position, in which it is capable of engaging the first cam stop surface, thereby restricting rotation of the cam body, and in the second position, it is not capable of engaging the first cam stop surface, thereby allowing rotation of the cam body.

[0015] In the example embodiment, the radius of each cam surface is measured from the corresponding first axis of rotation of the respective cam gear. Furthermore, as an example, the tube stop body includes a ring arranged coaxially with the central axis. When the tube stop body is in a first position, the ring can engage with the first cam stop surface, thus restricting rotation of the cam body. When the tube stop body is in a second position, the ring cannot engage with the first cam stop surface, thereby allowing rotation of the cam body. As an example, the first cam stop surface is positioned adjacent to a discontinuity of the cam surface on the cam body. The example embodiment also includes a rib extending from the cam body. The rib is positioned adjacent to the cam surface on the cam body and extends around a portion of the cam body. The first cam stop surface is positioned at a first end of the rib.

[0016] The example embodiment may also include a second cam stop surface positioned on a second end of the rib. The second cam stop surface extends from the cam body. The second cam stop surface is positioned spaced apart from the first cam stop surface. As an example, at least one of the first and second cam stop surfaces has a concave curvature. The example embodiment also includes a cup that surrounds a central axis and defines an opening for receiving a tube element when the tube element is inserted into the central space. The tube stop body is positioned within the cup. The cup is movable relative to the cam body along the central axis. In the example embodiment, the cup includes an inner surface having a first diameter at the opening and a second diameter distal to the opening. In this example, the first diameter is larger than the second diameter. In another example, the inner surface is tapered. A stop spring acts on the tube stop body to bias the tube stop body toward the opening of the cup. In another example, a cup spring acts on the cup to bias the cup toward the tube stop body. In the example embodiment, the tube stop body includes a plate capable of engaging with a tube element received in the central space. In this example, multiple legs extend from the plate. A ring is attached to a leg. The ring is arranged coaxially with a central axis. The cup includes a plurality of slots extending axially along the central axis. The leg extends through the slots. When the tube stop body is in a first position, the ring can engage with a first cam stop surface, thus restricting rotation of the cam body. When the tube stop body is in a second position, the ring cannot engage with the first cam stop surface, thereby allowing rotation of the cam body. The example embodiment also includes a shaft positioned coaxially with a central axis. The cup and the tube stop body surround the shaft.

[0017] Example embodiments may also include a plurality of synchronizing gears mounted within the housing. Each of the synchronizing gears is rotatable about a corresponding one of a plurality of second rotation axes. The second rotation axes are parallel to the first rotation axis, wherein each of the synchronizing gears meshes with two of the cam gears. In example embodiments, the number of synchronizing gears is one less than the number of cam gears. As an example, the device may include up to five cam gears and up to four synchronizing gears. In example embodiments, each of the cam surfaces may also include a region of a constant radius positioned adjacent to a corresponding one of the discontinuities. Example embodiments may also include a plurality of traction surfaces. Each of the traction surfaces extends about a corresponding one of the cam bodies. Another embodiment includes a plurality of first cam stop surfaces. Each of the first cam stop surfaces is positioned adjacent to a corresponding one of the discontinuities of one of the cam surfaces on each of the cam bodies.

[0018] The example embodiment may also include multiple ribs. Each rib extends from a corresponding one in the cam body. The ribs extend around a portion of the cam body. Each first stop surface is positioned at the end of each of the ribs. As an example, a traction surface overlays one of the cam surfaces. The traction surface may be positioned on the cam body at a distance from the cam surfaces extending around the cam body. In the example embodiment, the traction surface has a constant radius measured from a first axis of rotation of the cam body. In the example embodiment, the cam surface on the cam body is positioned between the gear and the traction surface on the cam body. In the example embodiment, the cam surface on the cam body is positioned close to the traction surface on the cam body. As another example, a first cam stop surface is positioned between the cam surface and the gear on the cam body.

[0019] Example embodiments may further include a first actuating surface positioned on a first of a plurality of cam bodies. The first actuating surface is offset from a first axis of rotation about which the first cam body rotates. An actuator may be movably mounted on a housing. The actuator is movable to engage with the first actuating surface for causing the first cam body to rotate about the first axis of rotation. In an example embodiment, the actuator includes a first lever pivotally mounted on the housing. The first lever has a drive surface that engages with the first actuating surface for causing the first cam body to rotate about the first axis. A second actuating surface is positioned on a second of a plurality of cam bodies. The second actuating surface is offset from a second axis of rotation about which the second cam body rotates. An overtravel stop is movably mounted on the housing. The overtravel stop is movable to engage with a second actuating surface for stopping the rotation of the second cam body about the second axis of rotation. In an example embodiment, the overtravel stop includes a second lever mounted on the housing for pivoting movement about a pivot axis. A hook is mounted on a second rod and positioned on one side of the pivot axis. The hook is capable of engaging a second working surface. A protrusion is mounted on the second rod on the opposite side of the pivot axis. A first rod is movable to engage the protrusion for pivoting the second rod to disengage the hook from the second working surface when the first rod is moved to engage the first working surface. A return spring acts between the housing and the second rod to bias the hook into engagement with the second working surface.

[0020] The example device may also include a chuck for receiving tube elements. The chuck is rotatable about a chuck axis. The chuck axis is arranged coaxially with a central axis. In the example embodiment, a housing is pivotally and axially slidably mounted near the chuck. The example embodiment may also include a motor engaged with the chuck for rotating the chuck about its axis. Attached Figure Description

[0021] Figure 1 This is an isometric view of an example device according to the invention mounted on a power chuck;

[0022] Figure 2 yes Figure 1 Exploded isometric view of the example device shown;

[0023] Figure 3 This is an axial view of the cam body component used in the device according to the present invention;

[0024] Figure 4 yes Figure 3 A side view of the cam body component shown;

[0025] Figure 5 Is Figure 1 A cross-sectional view taken at line 5-5;

[0026] Figure 6 Is Figure 1 Isometric view of the tubular element joining assembly used in the device shown;

[0027] Figure 7 and Figure 8 This is one aspect of the operation of the illustrated device. Figure 1 An isometric view of a portion of the apparatus shown;

[0028] Figures 9 to 11 It is a diagram. Figure 1 Partial cutaway isometric view of the operation of the device shown; and

[0029] Figure 12 yes Figure 6 A partial cross-sectional view of the pipe element joining assembly. Detailed Implementation

[0030] Figure 1 An example apparatus 10 is shown for cold-working a tube element 12 (e.g., forming a circumferential groove in the outer surface of the tube element). The apparatus 10 is shown mounted on a rotary power chuck 14. Such chucks are well known; one example is the Ridgid 300 Power Drive sold by Ridgid of Elyria, Ohio. The chuck 14 receives and rotates the tube element 12 as described below.

[0031] like Figure 2 As shown, the device 10 includes a housing 16. A plurality of cam gears (five in this example, cam gears 18, 20, 22, 24, and 26) are mounted within the housing 16. Each of the cam gears is rotatable about a corresponding axis of rotation 18a, 20a, 22a, 24a, and 26a. These first axes of rotation 18a, 20a, 22a, 24a, and 26a are oriented substantially parallel to each other and substantially parallel to the longitudinal axis 12a of the tube element 12. In a practical design, the cam gears 18, 20, 22, 24, and 26 are mounted on corresponding shafts 28. Shafts 28 extend between a front housing portion 30 and a rear housing portion 32, and each cam gear rotates on a bearing 34 coaxially mounted on the shaft 28. The cam gears 18, 20, 22, 24, and 26 are positioned around a central space 36 for receiving the tube element 12.

[0032] The device 10 also includes a plurality of cam bodies, five in this example: cam bodies 38, 40, 42, 44, and 46. Each cam body is mounted on a corresponding one of the cam gears 18, 20, 22, 24, 26, and 28. As illustrated by way of example with respect to cam body 38 on cam gear 18, each cam body includes a cam surface 50. Each cam surface 50 extends around a corresponding one of the cam bodies and is capable of engaging with the tube element 12 when received within the central space 36. Figure 3 As shown, using cam body 38 as an example, each of the cam surfaces 50 includes a discontinuity 54 of the cam surface 50 and a region 52 with an increasing radius. The radius 56 of each cam surface is measured from a corresponding one of the rotation axes 18a, 20a, 22a, 24a, 26a, and 28a; in the example shown, the radius 56 is measured from axis 18a. Each cam surface 50 may also include a region 58 of a constant radius, indicated by reference numeral 60. In practical designs, the region 58 of the constant radius of each cam surface 50 may advantageously be positioned adjacent to a corresponding one of the discontinuities 54 of the cam surface 50.

[0033] like Figure 3 and Figure 4 As shown, a traction surface 62 extends around at least one of the cam bodies (cam body 38 in this example). The traction surface 62 includes a plurality of protrusions 64 extending outwardly from the cam body 38. These protrusions may be knurled and provide mechanical engagement and gripping between the cam body 38 and the tube element 12 upon engagement. Unlike the cam surface 50, the traction surface 62 may have a constant radius measured from the axis of rotation 18a of the cam gear 18. The traction surface 62 also has a gap 66 therein. The gap 66 is axially aligned with the discontinuity 54 of the cam surface 50. Figure 4As shown, it is considered advantageous to position the cam surface 50 between the cam gear 18 and the traction surface 62, wherein the cam surface is positioned close to the traction surface. Figure 2 An example embodiment of the device 10 shown includes a plurality of traction surfaces 62 on the respective cam bodies 38, 40, 42, 44 and 46.

[0034] like Figure 5 As shown, device 10 also includes a plurality of synchronizing gears, in this example four synchronizing gears 68, 70, 72, and 74 mounted within housing 16. Each synchronizing gear is rotatable about a corresponding axis of rotation 68a, 70a, 72a, and 74a. These second axes of rotation are substantially parallel to the first axes of rotation 18a, 20a, 22a, 24a, 26a, and 28a of the cam gears. Each of the synchronizing gears 68, 70, 72, and 74 meshes with two of the cam gears to ensure that all cam gears and their associated cam bodies rotate together and remain relatively aligned with each other both in rotation and at rest for proper operation of device 10 as described below. Cam gear synchronization requires one less synchronizing gear than the number of cam gears. Therefore, in the example device 10, which includes at most five cam gears, only four synchronizing gears are required.

[0035] like Figure 2 As shown, the device 10 also includes a coupling assembly 76 positioned within the central space 36. As described below, when the tubular element 12 is inserted into the central space, the tubular element 12 contacts the coupling assembly. Figure 6 As shown, the engagement assembly 76 includes a cup 78. The cup 78 surrounds a central axis 80 arranged coaxially with the central space 36. The cup 78 defines an opening 82 for receiving the tube element 12 when it is inserted into the central space 36. In this example embodiment, the cup 78 includes an inner surface 84 having a first diameter 86 at the opening 82 and a second diameter 88 distal to the opening. The first diameter is larger than the second diameter. Furthermore, it is considered advantageous that the inner surface 84 is substantially tapered to accommodate a range of tube diameter tolerances. Figure 2 and Figure 12 As shown, the cup 78 is coaxially mounted with the shaft 90, which is installed within a tubular protrusion 91 attached to the rear housing portion 32. The shaft 90 is arranged coaxially with the central axis 80. The cup 78 is movable along the central axis 80 relative to the shaft 90 and the cam body. Figure 2 and Figure 12As shown, a cup spring 92 acts between the cup 78 and the rear housing portion 32 to bias the cup away from them. Advantageously, a thrust bearing 94 is positioned between the rear housing portion 32 and the cup spring 92 to protect the cup spring when the cup spring and the cup rotate together during device operation. In this example embodiment, the cup spring 92 is a tapered spring to allow for a maximum range of axial movement of the cup 78.

[0036] like Figure 2 , Figure 6 and Figure 12 As further shown, the engagement assembly 76 also includes a tube stop body 96 positioned within the cup 78. The tube stop body 96 is mounted on the shaft 90 and is movable relative to the shaft, cup, and cam body along the central axis 80. A stop spring 98 acts between the tubular protrusion 91 and the tube stop body 96 to bias the tube stop body toward the opening 82 defined by the cup 78. Advantageously, a thrust bearing 93 is inserted between the tubular protrusion 91 and both the stop spring 98 and the tube stop body 96. In the illustrated example embodiment, the tube stop body 96 includes a plate 100 that is capable of engaging the tube element 12 when it is received within the central space 36. A plurality of legs 102 extend from the plate 100, and a ring 104 is attached to the legs. The ring 104 is arranged coaxially with the central axis 80. The cup 78 defines a plurality of slots 106 that extend axially along the central axis 80. The slot 106 accommodates a leg 102 extending through the slot, thereby allowing relative movement between the tube stop body 96 and the cup 78 along the central axis 80.

[0037] like Figure 6 and Figure 7 As shown, mounting the ring 104 on the leg 102 allows the ring to have a larger diameter than the cup 78 for engaging a first cam stop surface 108 extending from one of the cam bodies 38 (see also...). Figure 4 ). As by Figure 7 and Figure 8 As the comparison shows, because the tube stop body 96 can move axially along the central axis 80, the ring 104 can be in a first position relative to the cam body 38. Figure 7 ) and second position ( Figure 8 The ring 104 moves between the first cam stop surface 108 and the second cam body 38. In the first position, the ring 104 can engage with or be engaged with the first cam stop surface 108, thereby restricting the rotation of the cam body 38. In the second position, the ring 104 cannot engage with the first cam stop surface 108, thereby allowing the rotation of the cam body 38. Note that due to the action of the synchronizing gears 68, 70, 72 and 74 (see...) Figure 5 If the rotation of any one of the cam bodies, such as cam body 38, is restricted, then the rotation of all the cam bodies is similarly restricted.

[0038] like Figure 4 As shown, the first cam stop surface 108 is advantageously positioned adjacent to the discontinuity 54 of the cam surface 50 on the cam body 38. Conveniently, the first cam stop surface 108 is positioned on the first end 110 of the rib 112 extending from the cam body 38. In this exemplary embodiment, the rib 112 is positioned adjacent to and extends around a portion of the cam surface 50 on the cam body 38. It is also considered advantageous to position the second cam stop surface 114 on the second end 116 of the rib 112. The second cam stop surface 114 also extends from the cam body 38 and is positioned in a spaced-apart relationship with the first cam stop surface 108. When the tube stop body 96 is in a first position in which the ring 104 engages with or is capable of engaging with either cam stop surface ( Figure 7 When the first cam stop surface 108 and the second cam stop surface 114 are used, the rotation of the cam body in either direction is restricted. This is considered advantageous if the first cam stop surface 108 and the second cam stop surface 114 each have a concave curvature that matches the curvature of the ring 104.

[0039] Although the actual design of the device 10 may have first and second cam stop surfaces positioned at the ends of ribs on a cam body, as Figure 2 As shown, it is also feasible to use multiple first cam stop surfaces 108 and second cam stop surfaces 114 positioned on multiple ribs 112 on multiple cam bodies.

[0040] like Figure 2 and Figure 5 As shown, the operation of the device 10 is enhanced by using an actuator 118 movably mounted on the housing 16. In this example embodiment, the actuator 118 includes a first lever 120 pivotally mounted on the housing 16. The first lever 120 has a drive surface 122 capable of engaging a first action surface 124 positioned on a first cam body, in this example, the cam body 40. The first action surface 124 is offset from the axis 20a of rotation of the cam body 40. Conveniently, a pin 126 mounted on the cam body 40 is used to form the action surface 124. The first lever 120 is pivotable such that its drive surface 122 engages the first action surface 124. Because the first action surface is offset from the axis of rotation 20a, the engagement between the drive surface and the action surface applies a torque to the cam body 40, causing the cam body 40 to rotate about its axis of rotation. The actuator 118 is used to initiate the engagement between the tube element 12 and one or more traction surfaces 62, thereby cold-working the tube element on the cam surface, as described below.

[0041] Another advantage is that the device 10 includes an overtravel stop 128. For example... Figure 2 and Figure 5 As further shown, the example overtravel stop 128 includes a second lever 130 mounted on the housing 16 for pivoting about a pivot axis 132. A hook 134 is mounted on the second lever 130 and positioned on one side of the pivot axis 132. The hook 134 is capable of engaging a second actuating surface 136, which is positioned on a second cam body, in this example, the cam body 38. The second actuating surface 136 is also offset from the axis of rotation 18a about which the second cam body 38 rotates, thereby allowing the hook 134 to apply torque on the second cam body to stop its rotation. Conveniently, a second pin 138 mounted on the second cam body 38 is used to define the second actuating surface 136. The overtravel stop 128 also includes a protrusion 140 mounted on the second lever 130. The protrusion 140 is positioned on the side of the pivot axis 132 opposite to the hook 134. The first lever 120 is movable to engage with the protrusion 140 for pivoting the second lever 130 to disengage the hook 134 from the second actuating surface 136. This engagement between the lever 120 and the protrusion 140 occurs during movement of the first lever, which positions the drive surface 122 of the first lever to engage with the first actuating surface 124 to initiate movement of the cam body. A return spring 142 acts between the housing 16 and the second lever 130 to bias the hook 134 to engage with the second actuating surface 136.

[0042] like Figure 1 As shown, operation of the device 10 begins when the tubular element 12 is inserted into the power chuck 14. The tubular element 12 is positioned such that its end extends from the front of the power chuck near the device 10, thus the chuck clamps the tubular element. The device 10 is in the position as shown... Figure 5 In the configuration shown, cam bodies 38, 40, 42, 44, and 46 are oriented such that the discontinuity 54 of the cam surface 50 and the gap 66 of one or more traction surfaces 62 both face the central axis 80. This configuration of the cam bodies provides a clearance that allows the tubular element 12 to be received within the central space 36. The cam bodies are held in this configuration by a constraint on their position established by a combination of features including: 1) a ring 104 that potentially engages one or both of a first cam stop surface 108 and a second cam stop surface 114 (not shown) on one or more of the cam bodies; 2) a hook 134 that potentially engages a second actuating surface 136; and 3) synchronizing gears 68, 70, 72, and 74. Figure 9 As shown, the cup 78 and the tube stop body 96 are both biased to their furthest positions away from the rear housing portion 32 by their respective cup springs 92 and stop springs 98. Figure 5As shown, the first lever 120 of the actuator 118 is positioned such that its drive surface 122 is ready to engage the first actuating surface 124 on the cam body 40. Figure 1 As shown, the device 10 is positioned on the power chuck 14 such that the longitudinal axis 12a of the tube is aligned with the central axis 80 of the device.

[0043] like Figure 10 As shown, by aligning housing 16 along mounting guide rail 144 (see...) Figure 1 The device 10 then slides and is moved to engage with the end of the tube element 12, such that the tube element is received within the central space 36 through the opening 146 in the front housing portion 30. As the device 10 moves further, the tube element 12 is received within the cup 78. Depending on where its diameter falls within tolerance, the tube element will engage the inner surface 84 of the cup somewhere between the cup opening 82 and the tube stop body 96. The engagement between the tube 12 and the cup 78 helps to mitigate the flaring of the tube end and also limits the tendency of the tube element to "go out of round" during cold working.

[0044] Further movement of device 10 relative to tube element 12 causes cup 78 to move relative to housing 16, compressing cup spring 92 and allowing tube element to engage plate 100 of tube stop body 96. Continued movement of tube element 12 causes tube stop body 96 to move relative to housing 16 until... Figure 11 and Figure 12 The plate 100 shown engages a thrust bearing 93, which surrounds the shaft 90 and abuts a tubular protrusion 91 extending from the rear housing portion 32. Figure 12 The thrust bearing 148 is positioned to position the tube element 12 relative to the cam surface 50 such that when the plate 100 and the thrust bearing 148 are engaged, and when the device 10 is actuated, a circumferential groove 150 will be formed in the tube element at a desired distance from the end of the tube element. The displacement of the tube stop body 96 against the thrust bearing 148 also causes the ring 104 to... Figure 7 The position shown is moved to Figure 8 The location shown is in Figure 7 In the position shown, the ring engages one or more first cam stop surfaces 108 or is capable of engaging one or more first cam stop surfaces 108, in Figure 8 In the position shown, ring 104 cannot engage one or more cam stop surfaces.

[0045] The actuation of device 10 is achieved by using motor 152 (see...) Figure 1This occurs to rotate the power chuck 14, thereby rotating the tube element 12. The tube element 12 can rotate immediately while it is being held by the chuck 14, or it can begin to rotate after the tube element is engaged with the device 10. As the tube element rotates, the first lever 120 of the actuator is pushed. This operation has two effects: 1) the first lever 120 engages the protrusion 140 of the second lever 130 (see...). Figure 5 ), thereby pivoting the second lever so that hook 134 disengages from the second action surface 136, allowing the cam body to rotate; and 2) moving the drive surface 122 of the lever to engage with the first action surface 124 of the cam body 40, causing all cam bodies 38, 40, 42, 44 and 46 to rotate by a small angular displacement via the action of synchronizing gears 68, 70, 72 and 74. This rotation of the cam body causes one or more traction surfaces 62 to engage with the tube element 12, which rotates under power from the chuck 14. Thus, the rotation of the tube element 12 acting on one or more traction surfaces drives the rotation of the cam body, which is kept in synchronizing rotation by synchronizing gears 68, 70, 72 and 74. The synchronizing rotation of the cam body causes the cam surface 50 to engage with the tube element 12, and as the outer surface of the tube element 12 is traversed by the region 56 of the cam surface 50 with an increasing radius and the region 58 of a constant radius, a circumferential groove 150 is formed (see Figure 3 ).like Figure 11 As shown, after one rotation of the cam bodies 38, 40, 42, 44, and 46, the groove 150 is fully formed. Because they are synchronized by the synchronizing gears 68, 70, 72, and 74, the cam bodies stop when the discontinuities 54 on the cam surface and one or more gaps 66 of one or more traction surfaces 62 face the central axis 80 again. Figure 5 As shown in the diagram. In this position, the tube element 12 is disengaged from one or more traction surfaces 62 and cam surface 50, and therefore rotation of the tube element will no longer cause the cam body to rotate. Note that upon release of the first lever 120 of the actuator 118, the second lever will pivot freely, such that the hook 134 of the overtravel stop 128, biased by its return spring 142, can re-engage the second acting surface 136 of the cam body 38, ensuring that the cam body stops and one or more traction surfaces 62 can no longer re-engage the tube element 12. At this point, the chuck 14 can stop, and the device 10 disengages from the tube element 12, and the tube element with the circumferential groove 150 can now be removed from the chuck.

[0046] The device 10 intended for use with cold-working tube elements will allow a circumferential groove to be formed in the tube element at a desired distance from the end of the tube element within the tube diameter tolerance, while reducing the flaring at the tube end and maintaining the roundness of the tube element.

Claims

1. An apparatus for cold working a pipe element, the apparatus comprising: a housing; a plurality of cam gears mounted within the housing, each of the cam gears being rotatable about a respective one of a plurality of first axes of rotation, the first axes of rotation being parallel to one another, the cam gears being positioned about a central space for receiving the pipe element; a plurality of cam bodies, each of the cam bodies being mounted on a respective one of the cam gears; a plurality of cam surfaces, each of the cam surfaces extending about a respective one of the cam bodies and being engageable with the pipe element received within the central space, each of the cam surfaces including a discontinuity of the cam surface and a region of increasing radius, each of the radii being measured from a respective one of the first axes of rotation; a drag surface extending about at least one of the cam bodies, the drag surface including a plurality of projections extending outwardly from the at least one cam body, the drag surface having a gap therein, the gap being axially aligned with the discontinuity of the one cam surface that surrounds the at least one cam body; an engagement assembly positioned within the central space, the pipe element contacting the engagement assembly when the pipe element is inserted into the central space; a plurality of synchronization gears mounted within the housing, each of the synchronization gears being rotatable about a respective one of a plurality of second axes of rotation, the second axes of rotation being parallel to the first axes of rotation; wherein each of the synchronization gears is in meshing engagement with two of the cam gears.

2. The apparatus of claim 1, wherein, each of the radii of each of the cam surfaces is measured from the respective first axis of rotation of the respective cam gear.

3. The apparatus of claim 1, wherein, the number of the synchronization gears is one less than the number of the cam gears.

4. The apparatus of claim 1, comprising at most five of the cam gears.

5. The apparatus of claim 4, comprising at most four of the synchronization gears.

6. The apparatus of claim 1, wherein, the engagement assembly includes a cup that surrounds a central axis and defines an opening for receiving the pipe element when the pipe element is inserted into the central space.

7. The apparatus of claim 6, wherein, the cup includes an inner surface having a first diameter at the opening and a second diameter distal of the opening, the first diameter being greater than the second diameter.

8. The apparatus of claim 7, wherein, the inner surface is tapered.

9. The apparatus of claim 7, further comprising a tube stop body positioned within the cup, the tube stop body being movable relative to the cup along the central axis, the cup being movable relative to the cam bodies along the central axis.

10. The apparatus of claim 9, further comprising: a ring mounted on the tube stop body concentrically with the central axis; a first cam stop surface protruding from one of the cam bodies; wherein The tube stop body is movable relative to the cam body between a first position in which the ring is engageable with the first cam stop surface thereby limiting rotation of the cam body and a second position in which the ring is not engageable with the first cam stop surface thereby allowing rotation of the cam body.

11. The apparatus of claim 10, wherein, The first cam stop surface is positioned adjacent the discontinuity of the cam surface on the one cam body.

12. The apparatus of claim 10, further comprising a rib extending from the one cam body, the rib being positioned adjacent the cam surface on the one cam body and extending around a portion of the one cam body, the first cam stop surface being positioned on a first end of the rib.

13. The apparatus of claim 12, further comprising a second cam stop surface positioned on a second end of the rib, the second cam stop surface extending from the one cam body, the second cam stop surface being positioned in spaced relation to the first cam stop surface.

14. The apparatus of claim 13, wherein, At least one of the first and second cam stop surfaces has a concave curvature.

15. The apparatus of claim 10, further comprising a stop spring acting on the tube stop body for biasing the tube stop body toward the opening of the cup.

16. The apparatus of claim 15, further comprising a cup spring acting on the cup for biasing the cup toward the tube stop body.

17. The apparatus of claim 10, wherein: the tube stop body includes a plate engageable with the tube element received within the central space, a plurality of legs extending from the plate, the ring being attached to the legs, the ring being disposed coaxially with the central axis; the cup includes a plurality of slots extending axially along the central axis, the legs extending through the slots.

18. The apparatus of claim 9, further comprising a shaft positioned coaxially with the central axis, the cup and the tube stop body surrounding the shaft.

19. The apparatus of claim 1, wherein, Each of the cam surfaces further includes a region of constant radius positioned adjacent a respective one of the discontinuities.

20. The apparatus of claim 1, further comprising a plurality of the traction surfaces, each of the traction surfaces extending around a respective one of the cam bodies.

21. The apparatus of claim 10, further comprising a plurality of the first cam stop surfaces, each of the first cam stop surfaces being positioned adjacent a respective one of the discontinuities of one of the cam surfaces on each of the cam bodies.

22. The apparatus of claim 21, further comprising a plurality of ribs, each of the ribs extending from a respective one of the cam bodies, the ribs extending around a portion of the cam bodies, each of the first cam stop surfaces being positioned on an end of each of the ribs.

23. The apparatus of claim 1, wherein, The traction surface is positioned on the one cam body in spaced relation to the cam surface extending around the one cam body.

24. The apparatus of claim 1, wherein, The traction surface has a constant radius measured from the first axis of rotation of the one cam body.

25. The apparatus of claim 21, wherein, The cam surface on the one cam body is positioned between the gear and the traction surface on the one cam body.

26. The apparatus of claim 25, wherein, The cam surface on the one cam body is positioned proximate the traction surface on the one cam body.

27. The apparatus of claim 25, wherein, The first cam stop surface is positioned between the cam surface and the gear on the one cam body.

28. The apparatus of claim 1, further comprising: a first action surface positioned on a first one of the cam bodies of the plurality of cam bodies, the first action surface being offset from a first one of the first axes of rotation, the first one of the cam bodies rotating about the first one of the first axes of rotation; an actuator movably mounted on the housing, the actuator being movable into engagement with the first action surface for rotating the first one of the cam bodies about the first one of the first axes of rotation.

29. The apparatus of claim 28, wherein, The actuator includes a first lever pivotally mounted on the housing, the first lever having a drive surface engageable with the first action surface for rotating the first one of the cam bodies about the first one of the axes.

30. The apparatus of claim 29, further comprising: a second action surface positioned on a second one of the cam bodies of the plurality of cam bodies, the second action surface being offset from a second one of the first axes of rotation, the second one of the cam bodies rotating about the second one of the first axes of rotation; an over-travel stop movably mounted on the housing, the over-travel stop being movable into engagement with the second action surface for stopping rotation of the second one of the cam bodies about the second one of the first axes of rotation.

31. The apparatus of claim 30, wherein, The over-travel stop includes: a second lever mounted on the housing for pivotal movement about a pivot axis, a hook is mounted on the second lever and positioned on one side of the pivot axis, the hook being engageable with the second action surface; a tab mounted on the second lever on an opposite side of the pivot axis, the first lever being movable into engagement with the tab for pivoting the second lever to move the hook out of engagement with the second action surface when the first lever is moved into engagement with the first action surface; a return spring acting between the housing and the second lever for biasing the hook into engagement with the second action surface.

32. The apparatus of claim 6, further comprising a chuck for receiving the tube element, the chuck being rotatable about a chuck axis, the chuck axis being coaxially arranged with the central axis.

33. The apparatus of claim 32, wherein, The housing is pivotably and axially slidably mounted adjacent the chuck.

34. The apparatus of claim 32, further comprising a motor engaged with the chuck for rotating the chuck about the chuck axis.

35. An apparatus for cold working a pipe element, the apparatus comprising: a housing; a plurality of cam gears mounted within the housing, each of the cam gears being rotatable about a respective one of a plurality of first rotational axes, the first rotational axes being parallel to one another, the cam gears being positioned about a central axis encompassed by a central space for receiving the pipe element; a plurality of cam bodies, each of the cam bodies being mounted on a respective one of the cam gears; a plurality of cam surfaces, each of the cam surfaces extending about a respective one of the cam bodies and being engageable with the pipe element received within the central space, each of the cam surfaces including a discontinuity of the cam surface and a region of increasing radius; a first cam stop surface projecting from one of the cam bodies; a pipe stop body positioned within the central space, the pipe stop body being engageable with the pipe element received within the central space, the pipe stop body being movable along the central axis relative to the cam bodies between a first position in which the first cam stop surface is engageable to thereby limit rotation of the cam bodies and a second position in which the first cam stop surface is not engageable to thereby permit rotation of the cam bodies; and a cup encompassing the central axis and defining an opening for receiving the pipe element as the pipe element is inserted into the central space, the pipe stop body being positioned within the cup, the cup being movable along the central axis relative to the cam bodies. Each of the radii of each of the cam surfaces is measured from the respective first rotational axis of the respective cam gear.

36. The apparatus of claim 35, wherein, The pipe stop body includes a ring arranged coaxially with the central axis, the ring being engageable with the first cam stop surface when the pipe stop body is in the first position and thereby limiting rotation of the cam bodies, and wherein the ring is not engageable with the first cam stop surface when the pipe stop body is in the second position to thereby permit rotation of the cam bodies.

37. The apparatus of claim 35, wherein, The first cam stop surface is positioned adjacent the discontinuity of the cam surface on the one cam body.

38. The apparatus of claim 35, wherein, 39. The apparatus of claim 35, further comprising a rib projecting from the one cam body, the rib being positioned adjacent the cam surface on the one cam body and extending about a portion of the one cam body, the first cam stop surface being positioned on a first end of the rib.

40. The apparatus of claim 39, further comprising a second cam stop surface positioned on a second end of the rib, the second cam stop surface projecting from the one cam body, the second cam stop surface being positioned in spaced relation to the first cam stop surface. At least one of the first and second cam stop surfaces has a concave curvature.

41. The apparatus of claim 40, wherein, ​ 42. The device of claim 35, wherein, The cup includes an inner surface having a first diameter at the opening and a second diameter distal of the opening, the first diameter being greater than the second diameter.

43. The device of claim 42, wherein, The inner surface is tapered.

44. The apparatus of claim 35, further comprising a stop spring acting on the tube stop body for biasing the tube stop body toward the opening of the cup.

45. The apparatus of claim 44, further comprising a cup spring acting on the cup for biasing the cup toward the tube stop body.

46. The apparatus of claim 35, wherein: the tube stop body includes a plate engageable with the tube element received within the central space, a plurality of legs extending from the plate, a ring attached to the legs, the ring being coaxially arranged with the central axis; the cup includes a plurality of slots extending axially along the central axis, the legs extending through the slots; wherein when the tube stop body is in the first position, the ring is engageable with the first cam stop surface and thereby limits rotation of the cam body, and wherein, when the tube stop body is in the second position, the ring is not engageable with the first cam stop surface, thereby allowing rotation of the cam body.

47. The apparatus of claim 35, further comprising a shaft positioned coaxially with the central axis, the cup and the tube stop body surrounding the shaft.

48. The device of claim 35, further comprising a plurality of synchronization gears mounted within the housing, each of the synchronization gears being rotatable about a respective one of a plurality of second rotational axes, the second rotational axes being parallel to the first rotational axis, wherein, each of the synchronization gears is meshed with two of the cam gears.

49. The device of claim 48, wherein, the number of the synchronization gears is one less than the number of the cam gears.

50. The apparatus of claim 48, comprising up to five of the cam gears.

51. The apparatus of claim 50, comprising up to four of the synchronization gears.

52. The device of claim 35, wherein, each of the cam surfaces further includes a region of constant radius positioned adjacent to a respective one of the discontinuities.

53. The apparatus of claim 35, further comprising a plurality of traction surfaces, each of the traction surfaces extending around a respective one of the cam bodies.

54. The apparatus of claim 35, further comprising a plurality of the first cam stop surfaces, each of the first cam stop surfaces being positioned adjacent to a respective one of the discontinuities in one of the cam surfaces on each of the cam bodies.

55. The apparatus of claim 54, further comprising a plurality of ribs, each of the ribs extending from a respective one of the cam bodies, the rib extending around a portion of the cam body, each of the first cam stop surfaces being positioned on an end of each of the ribs.

56. The device of claim 53, wherein, each of the traction surfaces covers a respective one of the cam surfaces.

57. The device of claim 53, wherein, each of the traction surfaces is positioned on the one cam body in spaced relation to the cam surface extending around the one cam body.

58. The device of claim 53, wherein, each of the traction surfaces has a constant radius measured from the first axis of rotation of the one cam body.

59. The device of claim 53, wherein, The cam surface on the one cam body is positioned between the gear and the traction surface extending around the one cam body.

60. The device of claim 59, wherein, The cam surface on the one cam body is positioned proximate the traction surface extending around the one cam body.

61. The device of claim 59, wherein, The first cam stop surface is positioned between the cam surface on the one cam body and the gear.

62. The apparatus of claim 35, further comprising: a first action surface positioned on a first one of the cam bodies of the plurality of cam bodies, the first action surface being offset from a first one of the first rotational axes about which the first one of the cam bodies rotates; an actuator movably mounted on the housing, the actuator being movable into engagement with the first action surface for rotating the first one of the cam bodies about the first one of the first rotational axes.

63. The device of claim 62, wherein, The actuator includes a first lever pivotally mounted on the housing, the first lever having a drive surface engageable with the first action surface for rotating the first one of the cam bodies about the first one of the axes.

64. The apparatus of claim 63, further comprising: a second action surface positioned on a second one of the cam bodies of the plurality of cam bodies, the second action surface being offset from a second one of the first rotational axes about which the second one of the cam bodies rotates; an over-travel stop movably mounted on the housing, the over-travel stop being movable into engagement with the second action surface for stopping rotation of the second one of the cam bodies about the second one of the first rotational axes.

65. The device of claim 64, wherein, The over-travel stop includes: a second lever mounted on the housing for pivotal movement about a pivot axis, a hook is mounted on the second lever and positioned on one side of the pivot axis, the hook being engageable with the second action surface; a tab is mounted on the second lever on an opposite side of the pivot axis, the first lever being movable into engagement with the tab for pivoting the second lever to move the hook out of engagement with the second action surface when the first lever is moved into engagement with the first action surface; a return spring acting between the housing and the second lever for biasing the hook into engagement with the second action surface.

66. The apparatus of claim 35, further comprising a chuck for receiving the tube element, the chuck being rotatable about a chuck axis, the chuck axis being coaxially arranged with the central axis.

67. The device of claim 66, wherein, The housing is pivotably and axially slidably mounted proximate the chuck.

68. The apparatus of claim 66, further comprising a motor engaged with the chuck for rotating the chuck about the chuck axis.

Images