GAGING DEVICE FOR CRIMPING MACHINE
United States Patent 3742754
In a machine of the type in which a fitting is radially crimped on a hose by a contractible collet, an arrangement wherein a collet, fitting, and hose may be assembled in a die ring at an unobstructed loading position on a machine bed plate before the die ring is moved laterally on the bed plate into a crimping station in alignment with an axis of a ram. The bed plate includes a slot from the loading position to the crimping station for passage therethrough of a hose extending from the die ring. The ram includes a slot, in alignment with the bed plate slot, for radial passage of a fitting portion therethrough to thereby minimize the ram stroke. A reversible pressure plate positionable on the collet and engageable by the ram evenly distributes the ram force to the collet area under the ram slot and,when it stops against the die ring, gages the final crimped sleeve diameter. At least one side of the plate is counterbored to receive a portion of the collet therein to selectively change the final crimped sleeve diameter from that produced when the opposite side is used to engage the collet and die ring. BACKGROUND OF THE INVENTION This invention relates to devices for reducing the diameter or size of cylindrical or similarly shaped parts and, in particular, relates to improvements in such devices of the type in which the shaping tool comprises a contractible collet. A principal application of a device embodying the present invention is the installation of tubular fitting assemblies on hose or tubing. According to a common practice in producing hose assemblies for moderate to high pressure service, a metal fitting or connector is permenently secured to a hose by plastically deforming or crimping an outer sleeve of the fitting around the hose end to cause the hose to be tightly held between the outer sleeve and a fitting nipple positioned inside the hose. The invention is directed to apparatus particularly suited for relatively low volume production such as for the makeup of replacement hoses in the field or at the point of use. DESCRIPTION OF THE PRIOR ART The present invention is adapted for use in the general type of machine disclosed in the patent application of B. H. Pauly et. al., Ser. No. 798,972, filed Feb. 13, 1969, now abandoned in favor of continuation Ser. No. 138,832, filed Apr. 29, 1971 and assigned to the assignee of this application. A machine of this type is provided with a fixed bed plate and a ram reciprocable towards and away from the bed. A die ring or socket and a segmented collet positioned in a tapered bore of the ring are axially compressed between the bed plate and ram. The segments or jaws of the collet are thereby cammed radially inward to constrict the collet bore around a fitting sleeve until the sleeve is permanently crimped onto a hose end. With apparatus as disclosed in the application of B. H. Pauly et. al., the ram must be extended and retracted over a relatively long stroke to afford adequate clearance for positioning the collet in the die ring and assembling a fitting and hose in the collet at the crimping station. Disadvantages associated with the long ram stroke include proportionately high actuator cost, long extension and retraction cycle time, and otherwise unnecessary machine bulk. Another disadvantage of such prior apparatus has been the necessity of providing a separate collet for each combination of hose size and pressure range. For a given hose size or inside diameter there may be, for example, three separate hose constructions for low, medium, and high pressure applications. Such hose constructions generally have different outside diameters and, consequently, each requires a sleeve to be crimped to a different final diameter. Previously, with this type of apparatus it has been necessary to provide a collet for each such final sleeve diameter. When needed, numerous collets have added to the cost of the apparatus and have detracted from its simplicity. SUMMARY OF THE INVENTION Apparatus in accordnace with the invention permits a collet and fitting to be assembled in the die ring at a loading point outside of the crimping station and unobstructed by the ram. As a consequence, the ram need not be retracted farther than where it provides enough clearance for the collet and die ring to be moved laterally from the loading point into the crimping station. Minimizing the ram stroke significantly reduces the cost of the ram actuator, cuts reciprocation cycle time, and lessens machine bulk to improve its portability. In the preferred embodiment, the bed plate extends laterally away from the crimping station beneath the ram to a point which is substantially unobstructed by the ram. At this point on the bed plate, a collet may be freely positioned in the die ring and a fitting and hose may be assembled in the collet. A slot is provided in the bed plate from the loading point to the crimping station to permit passage of the hose therebetween. Preferably, the ram includes a hollow driver with a side or radial slot in alignment with the bed plate slot to allow passage therethrough of a fitting extending out of the collet when the collet is moved into and out of the crimping position. A pressure plate is provided to evenly distribute the force of the ram to the collet segments beneath the driver slot. According to an additonal feature of the invention, the pressure plate is reversible side for side in the apparatus and includes gaging means for selectively limiting axial movement and, therefore, contraction of the collet in the die ring. This feature greatly reduces the number of collets necessary for covering a full range of hose size and pressure range combinations. Normally, the number of collets need only be equal to the number of different hose sizes; variations in outer diameter of hose of the same size are accommodated by use of a proper pressure plate side. As illustrated in the preferred embodiment, the pressure plate may be provided in the form of an apertured disc having a flat side and a counterbored side. The apparatus is arranged so that the ram stroke is limited or gaged when either side of the pressure plate abuts an opposing face of the die ring. The flat side of the pressure plate moves the collet to an axial position where its trailing end face is flush with the die ring face. Alternatively, the counterbored side, with the collet extending partially into the counterbore, moves the collet to an axial position somewhat short of that determined by the flat side. Thus, in the latter case the collet will crimp a sleeve to a final diameter somewhat larger than that produced when the flat side of the plate is used. Pressure or gage plates of varying counterbore depth may be provided to produce any desired axial movement and final sleeve diameter. A common set of pressure plates may be supplied for use with collets of all sizes.
US Patent References:
Crimping machine
Miller - February 1941 - 2231278
Apparatus for applying hose couplings to hoses
Albrecht - July 1962 - 3047043
Expanding tool
Vanderhoof - January 1963 - 3072174
Portable swaging device
Scudieri - July 1963 - 3096876
Swaging machine
Doerer - March 1968 - 3373474
Crimping machine
Miller - February 1941 - 2231278
Apparatus for applying hose couplings to hoses
Albrecht - July 1962 - 3047043
Expanding tool
Vanderhoof - January 1963 - 3072174
Portable swaging device
Scudieri - July 1963 - 3096876
Swaging machine
Doerer - March 1968 - 3373474
Inventors:
Jeromson Jr., James R. (Willoughby, OH)
Chen, Karl K. (Cleveland Hts., OH)
Chen, Karl K. (Cleveland Hts., OH)
Application Number:
05/191366
Publication Date:
07/03/1973
Filing Date:
10/21/1971
View Patent Images:
Export Citation:
Assignee:
The Weatherhead Company (Cleveland, OH)
Primary Class:
Other Classes:
72/453.010, 29/237
International Classes:
B21D39/04; B25B27/10; B25B27/02; B21D41/00
Field of Search:
72/402,453 29/237
Primary Examiner:
Lanham, Charles W.
Assistant Examiner:
Crosby, Gene P.
Claims:
What is claimed is
1. A machine for crimping a sleeve of a fitting on a hose comprising a bed plate, a ram reciprocable along an axis towards and away from the bed plate, said bed plate lying in a plane perpendicular to said ram axis, a die ring having a tapered bore therethrough and adapted to be positioned on the bed plate with the axis of the bore in alignment with the ram axis, said bed plate extending from the ram axis laterally a distance sufficient to support said die ring at a position thereon substantially unobstructed by the ram in an axial direction, a radially contractible collet assembly adapted to be positioned into and removed from the die ring bore when the ring is in said unobstructed position, said collet assembly including a central bore therethrough adapted to receive a fitting sleeve for crimping, a slot through said bed plate extending from said ram axis laterally to said unobstructed position to thereby permit a hose positioned in said sleeve to be moved with the collet assembly from said unobstructed position to said ram axis, reciprocation of said ram towards said bed plate causing said collet to move axially into said ring and thereby be radially contracted to crimp said sleeve onto said hose.
2. A machine as set forth in claim 1 wherein said ram includes a hollow driver, the walls of said driver terminating at a driving surface perpendicular to the ram axis, an axial slot through the driver wall extending from said driving surface and in angular alignment with said bed slot whereby a portion of a fitting extending outward of said collet may be moved radially into said driver and thereby minimize stroke of said ram.
3. A machine as set forth in claim 2 including a pressure plate having an aperture therethrough to permit said outwardly extending fitting portion to be positioned therein while said plate is positioned on a side of the collet assembly facing said ram, said plate being circumferentially continuous about said aperture, said pressure plate being engaged by said driver surface and distributing a force developed by said ram uniformly to said collet assembly including a portion of said collet adjacent said axial slot in said driver when said collet assembly is moved by said ram into said bore.
4. A machine as set forth in claim 3 wherein said pressure plate includes a pair of opposed faces, a first of said faces having a counterbore therein, said counterbore including an inner radial surface associated with said aperture at a predetermined axial distance from said first face, the width of said counterbore being greater than said collet side to permit said plate to be positioned on said collet with said collet side abutting said radial counterbore surface whereby said plate determines a first axial position and corresponding contraction of the collet when said first face engages said die ring, a second face of said plate including a surface portion engageable with said collet when the plate is reversed face for face and a surface portion engageable with the die ring, any axial distance between said surface portions being different than the axial distance between said first face and said radial counterbore surface such that when the die ring engaging surface portion of said second face abuts said die ring said collet is in an axial position and corresponding contraction different than that when said first face engages said die ring.
5. In combination in a machine for crimping a fitting on a hose comprising a bed, a ram reciprocable towards and away from the bed along an axis, force means for moving said ram along said axis, a die ring disposed between the bed and ram and including a tapered bore therein, a radially contractible collet in the tapered bore and adapted to be driven axially into said bore and thereby contracted by said ram, and reversible plate means to selectively determine the contraction of said collet, one side of said plate including means to limit movement of said collet to a first axial position in the die ring, the other side of said plate including means to limit axial movement of said collet to a second axial position.
6. The combination as set forth in claim 5 wherein said movement limiting means on said one side includes a counterbore in said one side.
7. The combination as set forth in claim 6 wherein said counterbore is adapted to receive a portion of the collet therein.
8. The combination as set forth in claim 7 wherein said force means to move said ram includes a piston and cylinder.
9. The combination as set forth in claim 8 wherein said piston and cylinder is of the single action type and said force means includes a spring for causing said ram to retract.
10. A machine for crimping a fitting on a hose comprising a bed, a ram reciprocal towards and away from the bed along an axis, force means for moving said ram along said axis, a die ring disposed between the bed and ram and including a tapered bore therein, a radially contractible collet in the tapered bore and adapted to be driven axially into said bore and thereby contracted by said ram, a pressure plate positionable between said collet and said ram to transmit the force of the ram to the collet, one side of said pressure plate having first and second axially spaced surfaces, the first plate surface being adapted to engage said collet and the second plate surface being adapted to engage said die ring, said pressure plate limiting axial motion of the collet to a first position when said second surface engages said die ring, another side of said pressure plate having a collet engaging surface portion and a die ring engaging surface portion, any axial distance between said surface portions being different than the axial spacing between the first and second surfaces of said one side whereby, when the pressure plate is reversed side for side, said pressure plate limits axial motion of the collet to a second position, different from said first position, as said die ring engaging surface portion engages said die ring.
1. A machine for crimping a sleeve of a fitting on a hose comprising a bed plate, a ram reciprocable along an axis towards and away from the bed plate, said bed plate lying in a plane perpendicular to said ram axis, a die ring having a tapered bore therethrough and adapted to be positioned on the bed plate with the axis of the bore in alignment with the ram axis, said bed plate extending from the ram axis laterally a distance sufficient to support said die ring at a position thereon substantially unobstructed by the ram in an axial direction, a radially contractible collet assembly adapted to be positioned into and removed from the die ring bore when the ring is in said unobstructed position, said collet assembly including a central bore therethrough adapted to receive a fitting sleeve for crimping, a slot through said bed plate extending from said ram axis laterally to said unobstructed position to thereby permit a hose positioned in said sleeve to be moved with the collet assembly from said unobstructed position to said ram axis, reciprocation of said ram towards said bed plate causing said collet to move axially into said ring and thereby be radially contracted to crimp said sleeve onto said hose.
2. A machine as set forth in claim 1 wherein said ram includes a hollow driver, the walls of said driver terminating at a driving surface perpendicular to the ram axis, an axial slot through the driver wall extending from said driving surface and in angular alignment with said bed slot whereby a portion of a fitting extending outward of said collet may be moved radially into said driver and thereby minimize stroke of said ram.
3. A machine as set forth in claim 2 including a pressure plate having an aperture therethrough to permit said outwardly extending fitting portion to be positioned therein while said plate is positioned on a side of the collet assembly facing said ram, said plate being circumferentially continuous about said aperture, said pressure plate being engaged by said driver surface and distributing a force developed by said ram uniformly to said collet assembly including a portion of said collet adjacent said axial slot in said driver when said collet assembly is moved by said ram into said bore.
4. A machine as set forth in claim 3 wherein said pressure plate includes a pair of opposed faces, a first of said faces having a counterbore therein, said counterbore including an inner radial surface associated with said aperture at a predetermined axial distance from said first face, the width of said counterbore being greater than said collet side to permit said plate to be positioned on said collet with said collet side abutting said radial counterbore surface whereby said plate determines a first axial position and corresponding contraction of the collet when said first face engages said die ring, a second face of said plate including a surface portion engageable with said collet when the plate is reversed face for face and a surface portion engageable with the die ring, any axial distance between said surface portions being different than the axial distance between said first face and said radial counterbore surface such that when the die ring engaging surface portion of said second face abuts said die ring said collet is in an axial position and corresponding contraction different than that when said first face engages said die ring.
5. In combination in a machine for crimping a fitting on a hose comprising a bed, a ram reciprocable towards and away from the bed along an axis, force means for moving said ram along said axis, a die ring disposed between the bed and ram and including a tapered bore therein, a radially contractible collet in the tapered bore and adapted to be driven axially into said bore and thereby contracted by said ram, and reversible plate means to selectively determine the contraction of said collet, one side of said plate including means to limit movement of said collet to a first axial position in the die ring, the other side of said plate including means to limit axial movement of said collet to a second axial position.
6. The combination as set forth in claim 5 wherein said movement limiting means on said one side includes a counterbore in said one side.
7. The combination as set forth in claim 6 wherein said counterbore is adapted to receive a portion of the collet therein.
8. The combination as set forth in claim 7 wherein said force means to move said ram includes a piston and cylinder.
9. The combination as set forth in claim 8 wherein said piston and cylinder is of the single action type and said force means includes a spring for causing said ram to retract.
10. A machine for crimping a fitting on a hose comprising a bed, a ram reciprocal towards and away from the bed along an axis, force means for moving said ram along said axis, a die ring disposed between the bed and ram and including a tapered bore therein, a radially contractible collet in the tapered bore and adapted to be driven axially into said bore and thereby contracted by said ram, a pressure plate positionable between said collet and said ram to transmit the force of the ram to the collet, one side of said pressure plate having first and second axially spaced surfaces, the first plate surface being adapted to engage said collet and the second plate surface being adapted to engage said die ring, said pressure plate limiting axial motion of the collet to a first position when said second surface engages said die ring, another side of said pressure plate having a collet engaging surface portion and a die ring engaging surface portion, any axial distance between said surface portions being different than the axial spacing between the first and second surfaces of said one side whereby, when the pressure plate is reversed side for side, said pressure plate limits axial motion of the collet to a second position, different from said first position, as said die ring engaging surface portion engages said die ring.
Description:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational, sectional view of a collet crimping apparatus in accordance with the invention and illustrating a die ring, collet and pressure plate in a loading position;
FIG. 2 is an elevational, sectional view of the collet crimping apparatus with the die ring at a crimping station and the pressure plate and collet in a crimping position;
FIG. 3 is an end view of the pressure plate illustrated in FIGS. 1 and 2;
FIG. 4 is a sectional view of the pressure plate, taken along the line 4--4 indicated in FIG. 3; and
FIG. 5 is an end view, opposite from FIG. 3, of the pressure plate.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 illustrates a crimping machine 10 embodying the principles of the invention. The machine 10 includes a bed plate 11, a ram 12, a die ring 13, and a collet 14. As discussed hereinbelow, the ram 12 is reciprocally movable towards the bed plate 11 to drive the collet 14 into the die ring 13 to thereby cause the collet 14 to contract and crimp a fitting sleeve.
The bed plate 11 is, preferably, a rectangular rigid plate and forms the base of the crimping machine 10. A slot 16 is machined or otherwise formed in the bed plate 11 from an area under the ram 12 laterally to a distal end 17 of the plate. Threaded into or otherwise fastened to the bed plate 11 is a set of four spaced rods 18 (of which only two appear in section) supporting the ram 12 on the bed plate and reacting against the forces developed by the ram.
Ideally, the ram 12 comprises a hydraulic actuator including a hollow cylinder 21 and a reciprocating piston 22 therein. The cylinder 21 is mounted between upper and lower end plates 23 and 24 respectively. Each rod 18 includes a reduced diameter portion 26 and a shoulder 27 against which the lower end plate 24 is abutted. Nuts 28 threaded on the upper end of the rod portions 26 are tightened to rigidly clamp the cylinder 21 between the end plates 23 and 24. The cylinder 21 is peripherally sealed in a counterbore 29 of the upper end plate 23 by an O-ring or like gasket 31.
The piston 22 includes a circular head portion 32 and an axially extending cylindrical portion 33 of reduced diameter. The circular head portion 32 has a pair of axially spaced peripheral grooves 34 for reception therein of a pair of resilient O-ring seals 36. The O-ring seals 36 seal against the inner periphery of the cylinder 21 so that a variable volume chamber is defined by the end plate counterbore 29, an end face 38 of the piston head 32 and the portion of the inner periphery of the cylinder 21 between the end plate 23 and piston head end face 38. The axes of the piston 22 and cylinder 21 define the axis of the ram 12 which is perpendicular to the bed plate 11. A port 41 in the upper end plate 23 communicates with the counterbore 29 and is connected by a line 42 to a two position spool valve 43. The valve 43 is connected to a pressure supply line 44 from a pump 45 and to a return line 46 to a reservoir 47.
A compression spring 48 in the cylinder 21 biases the piston 22 to the retracted position illustrated in FIG. 1. The cylindrical portion 33 of the piston 22 extends through and is guided for reciprocation by a bore 49 in the lower end plate 24. A cylindrical hollow driver 51 is secured to the piston portion 33 by a bolt 52. The driver 51 is provided with an end face 53 generally perpendicular, to the axis of the ram 12. A radial slot 54 through the wall of the driver 51 extends axially from its end face 53. This slot 54 in the driver is angularly aligned with the slot 16 in the bed plate 11.
The die block or ring 13 and collet 14 may be of the type disclosed in the aforementioned patent application of B. H. Pauly et al. or, as illustrated, may be of the types illustrated in the U. S. Patent application Ser. No. 187410 filed Oct. 7, 1971, of Irving Frank and assigned to the assignee of this application. As such, the collet 14 comprises a circular array of rigid, separate jaws or segments 57 held in angular alignment relative to one another by elastomeric material 58. Radially outer surfaces 61 of each jaw 57 preferably have the same angle of taper as a bore 56 in the die ring 13. Radial spaces (not shown) between the individual collet jaws 57 permit the collet jaws to radially contract relative to one another when they are cammed radially inwardly by the surface of the tapered bore 56 upon axial movement into the bore.
As illustrated in FIG. 1, the bed plate 11 extends laterally from beneath the ram 12 for a sufficient distance so that the die ring 13 may be supported thereon at a loading position where it is not significantly obstructed in an axial direction by the ram 12. It may be appreciated that the collet 14 may be vertically positioned into and removed from the die ring 13 and a fitting 66 may be vertically positioned in and removed from the collet 14 without obstruction by the ram at this loading point.
As disclosed in the aforesaid patent application Ser. No. 187,410 the collet jaws 57 are provided with radially inner surfaces 62 which normally circumscribe a generally circular bore of a diameter slightly smaller than the diameter of a sleeve 67 of the fitting 66 before it is crimped. Thus, when the fitting 66 is positioned in the collet 14 it is vertically supported therein by frictional contact with the radially inner surfaces 62 of the collet jaws 57. A hose 68 may be positioned in the fitting sleeve 67 at the loading position illustrated in FIG. 1 so that it extends through the bed plate slot 16. Ordinarily there will be sufficient interference between the end of the hose 68 and the fitting 66 inside of the sleeve 67 to provisionally retain the hose therein until the sleeve is permanently crimped thereon.
A pressure plate 71 is positioned on an upper face 72 of the collet 14. The pressure plate 71 is preferably circular includes a central aperture or bore 73 for passage therethrough of a portion of the fitting 66 extending out of the collet 14. As arranged in FIGS. 1 and 2, the pressure plate 71 is provided with a flat upper side or face 74 and a lower side or face 76 which includesa counterbore 77 therein. The counterbore 77, preferably, is cylindrical and has a diameter or width greater than the diameter of the upper collet face 72 so that the collet 14 is received in the counterbore and abuts a radial surface 78 of the counterbore. This radial counterbore surface 78 is parallel to the portion, designated 79, of the lower face 76 surrounding the counterbore 77 and parallel to the upper face 74.
With the fitting 66 and hose 68 properly positioned in the collet 14 and the pressure plate 71 centered on the collet, the die ring 13 may be manually moved from the loading position laterally on the bed plate 11 until it is centered in a crimping position under the ram 12 with its axis coincident with that of the ram. The machine 10 may then be energized to crimp the sleeve 67 on the hose 68 by shifting the spool valve 43 to the position illustrated in FIG. 2 where pressurized fluid from the pump 45 is directed through the line 42 into the cylinder 21 to operate against the end face 38 of the piston 22 and thereby force the driver 51 downwardly towards the pressure plate 71. The pressure plate 71 distributes the force developed by the ram 12 evenly to the collet jaws 57 including those adjacent the driver slot 54.
When the driver end face 53 contacts the upper face 74 of the pressure plate 71, the plate begins to move the collet 14 axially into the tapered die block bore 56. Axial motion of the ram 12 is limited or gaged when the peripheral surface 79 of the lower plate surface 76 engages an upper face 81 of the die block 13, the condition illustrated in FIG. 2. Pressure supplied by the pump 45 is sufficient to drive the collet 14 to its crimping position but its maximum pressure is limited to that which will not over stress the hydraulic circuit or ram when the pressure plate 71 engages the die block 13.
The ram 12 is retracted from its extended position by shifting the spool valve 43 back to the position illustrated in FIG. 1 where fluid in the cylinder 21 is vented back through the line 42 into the reservoir 47 through the line 46. This permits the compression spring 48 to force the piston 22 upwardly away from the bed plate 11. The die block 13 may thereafter be manually moved from the crimping position back to the loading position where the hose 68 and fitting 66, now permanently assembled, may be removed from the collet 14.
It will be understood that because the collet 14 and fitting 66 are conveniently assembled in and disassembled from the die ring 13 at a point unobstructed by the arm 12, the stroke of the ram may be minimized. A portion of the fitting 66 extending above the pressure plate 71 may pass through the driver slot 54 so that the driver 51 need only be retracted far enough to permit the die ring 13, collet 14, and pressure plate 71, regardless of which pressure plate face 74 or 76 is up, to be moved laterially thereunder. The short ram stroke results in savings in ram actuator cost by permitting the use of a single acting spring return type piston and cylinder, lowers reciprocation cycle time, reduces pump capacity requirements, and improves the portability of the machine by reducing its weight and size.
As previously indicated in the summary of the invention above, the pressure plate 71 may be reversed face for face. Inverting the plate from the position illustrated in FIGS. 1 and 2 determines a different final crimping diameter of the sleeve 67 to thereby adjust for differences in hose construction. For example, a given hose size, measured by inside diameter, may have three distinct outside diameters corresponding to low, medium and high pressure ratings. Generally, it is possible to use the same size of fitting and the same collet for hose of the same inside diameter but the external fitting sleeve, in each case, must be crimped to a different final diameter. When the plate 71 is reversed, a portion of the illustrated upper plate surface 74 is adapted to engage the upper surface 72 of the collet. Other portions of the surface 74 are adapted to engage the upper face 81 of the die block 13 to limit or gage motion of the ram 12 and collet 14. It may be appreciated that reversal of the plate 71 thereby causes the collet 14 to be moved axially into the bore 56 farther than the position illustrated in FIG. 2 and thereby causes a sleeve to be crimped to a smaller final diameter.
FIGS. 3 through 5 separately illustrate the pressure plate 71. As shown each side 74 and 76 of the pressure plate 71 may be imprinted with a legend for the convenience of an operator in selecting a side corresponding to the particular hose being used. It may further be understood that final crimped sleeve diameters of a size between that produced by the sides 74 and 76 of the plate 71 may be achieved by providing another pressure plate having a shallower counterbore than that illustrated. Further, it may be desirable to provide a plate having counterbores of different depths on both sides.
Although a preferred embodiment of the invention has been shown and described in detail, it is to be understood that various modifications and rearrangements may be resorted to without departing from the scope of the invention.
FIG. 1 is an elevational, sectional view of a collet crimping apparatus in accordance with the invention and illustrating a die ring, collet and pressure plate in a loading position;
FIG. 2 is an elevational, sectional view of the collet crimping apparatus with the die ring at a crimping station and the pressure plate and collet in a crimping position;
FIG. 3 is an end view of the pressure plate illustrated in FIGS. 1 and 2;
FIG. 4 is a sectional view of the pressure plate, taken along the line 4--4 indicated in FIG. 3; and
FIG. 5 is an end view, opposite from FIG. 3, of the pressure plate.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 illustrates a crimping machine 10 embodying the principles of the invention. The machine 10 includes a bed plate 11, a ram 12, a die ring 13, and a collet 14. As discussed hereinbelow, the ram 12 is reciprocally movable towards the bed plate 11 to drive the collet 14 into the die ring 13 to thereby cause the collet 14 to contract and crimp a fitting sleeve.
The bed plate 11 is, preferably, a rectangular rigid plate and forms the base of the crimping machine 10. A slot 16 is machined or otherwise formed in the bed plate 11 from an area under the ram 12 laterally to a distal end 17 of the plate. Threaded into or otherwise fastened to the bed plate 11 is a set of four spaced rods 18 (of which only two appear in section) supporting the ram 12 on the bed plate and reacting against the forces developed by the ram.
Ideally, the ram 12 comprises a hydraulic actuator including a hollow cylinder 21 and a reciprocating piston 22 therein. The cylinder 21 is mounted between upper and lower end plates 23 and 24 respectively. Each rod 18 includes a reduced diameter portion 26 and a shoulder 27 against which the lower end plate 24 is abutted. Nuts 28 threaded on the upper end of the rod portions 26 are tightened to rigidly clamp the cylinder 21 between the end plates 23 and 24. The cylinder 21 is peripherally sealed in a counterbore 29 of the upper end plate 23 by an O-ring or like gasket 31.
The piston 22 includes a circular head portion 32 and an axially extending cylindrical portion 33 of reduced diameter. The circular head portion 32 has a pair of axially spaced peripheral grooves 34 for reception therein of a pair of resilient O-ring seals 36. The O-ring seals 36 seal against the inner periphery of the cylinder 21 so that a variable volume chamber is defined by the end plate counterbore 29, an end face 38 of the piston head 32 and the portion of the inner periphery of the cylinder 21 between the end plate 23 and piston head end face 38. The axes of the piston 22 and cylinder 21 define the axis of the ram 12 which is perpendicular to the bed plate 11. A port 41 in the upper end plate 23 communicates with the counterbore 29 and is connected by a line 42 to a two position spool valve 43. The valve 43 is connected to a pressure supply line 44 from a pump 45 and to a return line 46 to a reservoir 47.
A compression spring 48 in the cylinder 21 biases the piston 22 to the retracted position illustrated in FIG. 1. The cylindrical portion 33 of the piston 22 extends through and is guided for reciprocation by a bore 49 in the lower end plate 24. A cylindrical hollow driver 51 is secured to the piston portion 33 by a bolt 52. The driver 51 is provided with an end face 53 generally perpendicular, to the axis of the ram 12. A radial slot 54 through the wall of the driver 51 extends axially from its end face 53. This slot 54 in the driver is angularly aligned with the slot 16 in the bed plate 11.
The die block or ring 13 and collet 14 may be of the type disclosed in the aforementioned patent application of B. H. Pauly et al. or, as illustrated, may be of the types illustrated in the U. S. Patent application Ser. No. 187410 filed Oct. 7, 1971, of Irving Frank and assigned to the assignee of this application. As such, the collet 14 comprises a circular array of rigid, separate jaws or segments 57 held in angular alignment relative to one another by elastomeric material 58. Radially outer surfaces 61 of each jaw 57 preferably have the same angle of taper as a bore 56 in the die ring 13. Radial spaces (not shown) between the individual collet jaws 57 permit the collet jaws to radially contract relative to one another when they are cammed radially inwardly by the surface of the tapered bore 56 upon axial movement into the bore.
As illustrated in FIG. 1, the bed plate 11 extends laterally from beneath the ram 12 for a sufficient distance so that the die ring 13 may be supported thereon at a loading position where it is not significantly obstructed in an axial direction by the ram 12. It may be appreciated that the collet 14 may be vertically positioned into and removed from the die ring 13 and a fitting 66 may be vertically positioned in and removed from the collet 14 without obstruction by the ram at this loading point.
As disclosed in the aforesaid patent application Ser. No. 187,410 the collet jaws 57 are provided with radially inner surfaces 62 which normally circumscribe a generally circular bore of a diameter slightly smaller than the diameter of a sleeve 67 of the fitting 66 before it is crimped. Thus, when the fitting 66 is positioned in the collet 14 it is vertically supported therein by frictional contact with the radially inner surfaces 62 of the collet jaws 57. A hose 68 may be positioned in the fitting sleeve 67 at the loading position illustrated in FIG. 1 so that it extends through the bed plate slot 16. Ordinarily there will be sufficient interference between the end of the hose 68 and the fitting 66 inside of the sleeve 67 to provisionally retain the hose therein until the sleeve is permanently crimped thereon.
A pressure plate 71 is positioned on an upper face 72 of the collet 14. The pressure plate 71 is preferably circular includes a central aperture or bore 73 for passage therethrough of a portion of the fitting 66 extending out of the collet 14. As arranged in FIGS. 1 and 2, the pressure plate 71 is provided with a flat upper side or face 74 and a lower side or face 76 which includesa counterbore 77 therein. The counterbore 77, preferably, is cylindrical and has a diameter or width greater than the diameter of the upper collet face 72 so that the collet 14 is received in the counterbore and abuts a radial surface 78 of the counterbore. This radial counterbore surface 78 is parallel to the portion, designated 79, of the lower face 76 surrounding the counterbore 77 and parallel to the upper face 74.
With the fitting 66 and hose 68 properly positioned in the collet 14 and the pressure plate 71 centered on the collet, the die ring 13 may be manually moved from the loading position laterally on the bed plate 11 until it is centered in a crimping position under the ram 12 with its axis coincident with that of the ram. The machine 10 may then be energized to crimp the sleeve 67 on the hose 68 by shifting the spool valve 43 to the position illustrated in FIG. 2 where pressurized fluid from the pump 45 is directed through the line 42 into the cylinder 21 to operate against the end face 38 of the piston 22 and thereby force the driver 51 downwardly towards the pressure plate 71. The pressure plate 71 distributes the force developed by the ram 12 evenly to the collet jaws 57 including those adjacent the driver slot 54.
When the driver end face 53 contacts the upper face 74 of the pressure plate 71, the plate begins to move the collet 14 axially into the tapered die block bore 56. Axial motion of the ram 12 is limited or gaged when the peripheral surface 79 of the lower plate surface 76 engages an upper face 81 of the die block 13, the condition illustrated in FIG. 2. Pressure supplied by the pump 45 is sufficient to drive the collet 14 to its crimping position but its maximum pressure is limited to that which will not over stress the hydraulic circuit or ram when the pressure plate 71 engages the die block 13.
The ram 12 is retracted from its extended position by shifting the spool valve 43 back to the position illustrated in FIG. 1 where fluid in the cylinder 21 is vented back through the line 42 into the reservoir 47 through the line 46. This permits the compression spring 48 to force the piston 22 upwardly away from the bed plate 11. The die block 13 may thereafter be manually moved from the crimping position back to the loading position where the hose 68 and fitting 66, now permanently assembled, may be removed from the collet 14.
It will be understood that because the collet 14 and fitting 66 are conveniently assembled in and disassembled from the die ring 13 at a point unobstructed by the arm 12, the stroke of the ram may be minimized. A portion of the fitting 66 extending above the pressure plate 71 may pass through the driver slot 54 so that the driver 51 need only be retracted far enough to permit the die ring 13, collet 14, and pressure plate 71, regardless of which pressure plate face 74 or 76 is up, to be moved laterially thereunder. The short ram stroke results in savings in ram actuator cost by permitting the use of a single acting spring return type piston and cylinder, lowers reciprocation cycle time, reduces pump capacity requirements, and improves the portability of the machine by reducing its weight and size.
As previously indicated in the summary of the invention above, the pressure plate 71 may be reversed face for face. Inverting the plate from the position illustrated in FIGS. 1 and 2 determines a different final crimping diameter of the sleeve 67 to thereby adjust for differences in hose construction. For example, a given hose size, measured by inside diameter, may have three distinct outside diameters corresponding to low, medium and high pressure ratings. Generally, it is possible to use the same size of fitting and the same collet for hose of the same inside diameter but the external fitting sleeve, in each case, must be crimped to a different final diameter. When the plate 71 is reversed, a portion of the illustrated upper plate surface 74 is adapted to engage the upper surface 72 of the collet. Other portions of the surface 74 are adapted to engage the upper face 81 of the die block 13 to limit or gage motion of the ram 12 and collet 14. It may be appreciated that reversal of the plate 71 thereby causes the collet 14 to be moved axially into the bore 56 farther than the position illustrated in FIG. 2 and thereby causes a sleeve to be crimped to a smaller final diameter.
FIGS. 3 through 5 separately illustrate the pressure plate 71. As shown each side 74 and 76 of the pressure plate 71 may be imprinted with a legend for the convenience of an operator in selecting a side corresponding to the particular hose being used. It may further be understood that final crimped sleeve diameters of a size between that produced by the sides 74 and 76 of the plate 71 may be achieved by providing another pressure plate having a shallower counterbore than that illustrated. Further, it may be desirable to provide a plate having counterbores of different depths on both sides.
Although a preferred embodiment of the invention has been shown and described in detail, it is to be understood that various modifications and rearrangements may be resorted to without departing from the scope of the invention.