TUBE END FINISHING MACHINE

Abstract: A machine for finishing the ends of cylindrical workpieces including a common, manually operable control member (80) for sequentially actuating a pneumatic work clamp (20), initiating motor operation of a machining tool (71) and manually advancing the tool (71) into engagement with the clamped workpiece (A).

Description: 1. TUBE END FINISHING MACHINE 2. 3. BACKGROUND OF THE INVENTION 4. FIELD OF THE INVENTION 5. 6. The present invention relates to metal working 7. machinery and more particularly to machines of the types 8. disclosed and claimed in applications Serial No. 06/ 881 ,918 9. filed July 3 , 1986 and Serial No. 07/093 ,591 filed September 10. 8 , 1987 for finishing the ends of cylindrical work pieces 11. such as metal tubes or rods. 12. 13. THE PRIOR ART 14. 15. Machines designed for the purposes of the present 16. invention comprise essentially a housing in which there are 17. coaxially mounted a work holding assembly operable to grip 18. or release a work piece , and means including an axially 19. movabl e , rotatabl e spindl e for performing machining 20. operations on the end of a tube gripped by the work holding * 21. assembly. Examples of such machines are disclosed in the 22. U. S . patents of Strout No . 3 ,228 , 268 and S ai ne No . 23 . 4 ,319,503. Such a machine employing a clamshell type of 24. work holder pivoted on an axis paralleling the spindle axis 25. is catalogued by Conrac Corporation and identified as its 26. Tubemaster series of models. 1. Such machines are constructed in two general types; 2. one for bench use where continuous runs of identical work 3. pieces are to be produced, and another portable type for use 4. in situations in which tubing needs to be machined in the 5. field to fit special needs. In the case of both types, 6. there is a need for greater automation of the work clamping, 7. tool feeding and motor drive controls than prior machines of 8. the type have provided. Separate actuation of work clamping 9. means, tool feeding means and motor control means 10. necessarily slows production on bench type machines and, in 11. the case of portable machines which, additionally, must be 12. held in place with respect to the work piece, manual 13. operation of separate controls becomes extremely awkward. 14. 15. SUMMARY OF THE INVENTION 16. 17. According to the present invention, a machine for 18. finishing an end of a cylindrical work piece such as a tube 19. or rod is provided in which manual operation of a single 20. control, such as a lever, sequentially actuates a work * 21. holder to clamp a work piece in position for finishing; 22. initiates rotation of the motor driven tool spindle; and 23. manually shifts the finishing tooling into engagement with 24. the end of the clamped work piece. This arrangement 25. preserves the desirable feature of direct manual control of 26. the contact between the finishing tooling and the work 1. piece, while at the same time providing automatic sequencing 2. of the clamping and drive initiation. 3. 4. BRIEF DESCRIPTION OF THE DRAWINGS 5. 6. Figure 1 is a view in side elevation of a tube and 7. rod end finishing machine embodying the present invention. 8. Figure 2 is a view in plan of the machine of Figure 9. 1, partially in section taken along the line 2—2 of Figure 10. 1. 11. Figure 3 is a view in end elevation of the machine 12. of Figure 1, partially in section taken along the line 3—3 13. of Figure 1. 14. Figure 4 is a view in front elevation of the machine 15. of Figure 1, partially in section taken along the line 4—4 16. of Figure 1. 17. Figure 5 is a diagram of the el ect r i ca l and 18. pneumatic connections of the machine of Figure 1. 19. 20. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 21. 22. As shown in the accompanying drawings , a preferred 23. embodiment of the present invention comprises a base plate 7 24. supported on feet 8 and supporting a cylindrical housing 25. assembly 10 connected to the base plate 7 by bolts 9 . The 26. housing assembly 10 includes a central section 11 (Fig. 2 ) , 1. a rear housing 12 having a portion of reduced diameter 2. received into one end of the central section as at 13, and a 3. front housing 14 having a portion of reduced diameter 4. received into the opposite end of the central section as at 5. 15. Three cap screws 17 (see also Fig. 3) received in bores 6. in the rear housing 12 and in threaded recesses 18 in front 7. housing 14 secure the elements of the housing assembly 10 8. together. 9. Means including a clamshell type work holder 10. assembly 20 are provided for securing a cylindrical work 11. piece A (Fig. 2) in position adjacent the front housing 14. 12. This means comprises a lower jaw 22 (Fig. 1) integral with 13. the front housing 14 and an upper jaw 24 secured to a pair 14. of swing brackets 25 which are pivotally mounted at 26 on 15. the front housing 14 for pivotal movement on a transverse 16. axis disposed centrally of the housing assembly 10. 17. As shown in Figure 2, the lower jaw 22 is provided 18. with means for removably mounting a semicircular die 27 of a 19. size appropriate to the diameter of the work piece to be 20. machined. This means comprises a dovetail, joint 28 between 21. the jaw and die permitting removal of the die by rotational 22. movement with respect to the jaw; inadvertent displacement 23. of the die being prevented by a spring-pressed ball retainer 24. 29 (Fig. 4) engaging an indentation in the die. An upper 25. die 30 (Fig. 4) complementary to the die 27 is similarly 26. mounted in the upper jaw 24 where it is removably retained 1. by a similar spring-pressed ball retainer 31. 2. Movement of the upper j aw 24 between the work 3. clamping position in which it is shown in Figure 1 and its 4. work releasing position shown in ghosted lines in that 5. Figure is effected by means comprising a double-acting 6. pneumatic cylinder assembly 35 pivotally mounted at 36 7. between a pair of brackets 37 depending from the base plate 8. 7. Piston rod 40 of the cylinder assembly 35 is connected 9. at its free end 41 to a clevis beam 42 (see also Fig. 4) 10. pivotally connected to the lower ends of a pair of clamp 11. links 43 pivotally connected at their upper ends at 44 to 12. the upper jaw 24 of the clamshell work holder assembly 20. 13. Adjustable means are provided for clamping the 14. upper jaw 24 against a work piece in the lower jaw 22 when 15. the upper jaw is moved to its closed position. As shown in 16. Figure 4 this means comprises a pivot shaft 47 journalled in 17. a cross bar 48 integral with the front housing 14 and having 18. a screwdriver slot at one end and an eccentric central 19. portion 49. A pivot arm 50 pivotally mounted on the 20. eccentric portion 49 of shaft 47 is integral with spaced end 21. portions 52 of a pair of pivot arm extensions 53 , each 22. pivotally mounted in one of the clamp links 43. Another 23. portion of shaft 47 is provided with a portion of reduced 24. diameter 54 , opposite sides of which are engageable by 25. spaced clamps 55 threaded on a screw 56 having a hexagonal 26. tool recess in its outer end whereby it may be rotated to 1. vary the compression exerted on pivot shaft 47. 2. As clamp links 43 move from the position shown in 3. ghosted lines in Figure 1 to the portion shown in full lines 4. in that Figure in which jaws 22 and 24 are closed, the 5. pivotal connection 41 moves vertically a distance determined 6. by the rotational setting of pivot shaft 47, carrying with 7. it pivot arm 50, pivot arm extensions 53 and clamp links 43. 8. This arrangement is such that, by appropriate setting of the 9. shaft 47, upper jaw 24 may be caused to clamp more or less 10. closely against lower jaw 22 before the links 43 reach a 11. position in which they are arrested by engagement of the 12. right clamp link 43 with a stop 51 secured to the front 13. housing 14. This effects clamping of the jaws 22 and 24 14. against an inserted work piece. 15. Means are provided for performing machining 16. operations on a work piece clamped in the work holder. As 17. shown in Figure 2 there is journalled in bearings in the 18. rear housing 12 and front housing 14 with freedom for axial 19. movement, a spindle 57 having a threaded socket 58 at its 20. front end for the reception of any of various kinds of 21. machining tools. Fixed to the spindle 57 intermediate its 22. ends is a spur gear 59, and a spring 60 is compressed 23. between the gear 59 and the front housing 14 to normally 24. maintain the spindle 57 in its rearmost position. 25. Rotation of spindle 57 is effected by means 26. including a drive shaft 62 journalled in the rear housing 12 27. and having at its front end a drive pinion 63 of sufficient 1. length to mesh with the spur gear 59 in all axial 2. positionings thereof. A belt drive 65 contained in a 3. suitable housing 66 connects drive shaft 62 with a drive 4. motor 67 mounted on the base plate 7. 5. Threaded for reception in the socket 58 (Fig. 1) is 6. a cutter assembly 68 comprising a threaded stem 69 and a 7. head 70 provided with means for adjustably mounting thereon 8. a machining tool 71. 9. A stock stop 75 has a stem 76 slidably received in a 10. bore radially spaced from the axis of threaded stem 69 and a 11. head 77 of a diameter sufficient to constitute an abutment 12. limiting the insertion between jaws 22 and 24 and any of a 13. variety of diameters of work pieces. The stock stop's stem 14. 76 is of sufficient length to maintain the head 77 spaced 15. from the front face of the cutter assembly head when the end 16. of the stem 76 engages the front face of the front housing 17. 14, as shown. A snap ring 78 on stem 76 prevents accidental 18. removal of the stock stop 75 from the cutter assembly 68. 19. A common control means is provided for performing in 20. the proper sequence the clamping of a work piece in position 21. for machining oeprations; the initiation of operation of 22. the machining tool means; and the advancing of the tool 23. means into engagement with the clamped work piece. 24. Movement of spindle 57 in the direction of a work 25. piece clamped in the work holder is effected by an operating 26. lever 80 (Fig. 1) fixed to an operating shaft 81 which is 27. rockable through an arc of approximately 180 degrees as 1. determined by the settings of an adjustable retraction stop 2. 82 and an adjustable forward stop 83. The operating shaft 3. 81 carries at its inner end (see also Fig. 2 ) a pin 85 4. eccentrically mounted on the shaft' s end and engaging a 5. thrust button 86 retained in a central recess 87 in the rear 6. end of the spindle 57. This arrangement is such that, upon 7. manual movement of the operating lever 80 in a clockwise 8. direction as viewed in Figure 1, the spindle 57 carrying its 9. machining tool is moved forward bringing the tool 71 into 10. contact with the end of the clamped work piece. 11. As shown in Figure 5 , forward movement of the 12. operating lever 80 effects clockwise movement of operating 13. • shaft 81 raising eccentr ic pin 85 . In the retracted 14. position of the operating lever, a switch actuating pin 90 15. slidably mounted in a bracket 91 on the rear housing 12 and 16. urged upwardly by a compression spring 92 , is held in its 17. lower position in which it maintains open the contacts of an 18. electrical switch 93. The initial forward movement of 19. operating lever 80 releases the switch and actuating pin 90 20. effecting closure of the contacts of switch 93. 21. Closure of the contacts of switch 93 completes a 22. circuit from a power source 95 to the drive motor 67 thus 23. initiating rotation of the spindle 57 , and also completes a 24. circuit from the power source 95 to a solenoid actuated 25. four-way pneumatic valve 96 which may be, for example, one 26. manufactured by Compair Mfg. Co. catalogued as No. 8N502-K32 27. spring returned solenoid valve distributed by Fillmore & 1. Garber of El Monte, California. Upon energization of the 2. solenoid of valve 96 , air under compression from a supply 3. line 97 is admitted to the pneumatic cylinder assembly 35 at 4. the rear of the piston 38 extending the piston rod 40 to the 5. position in which it is shown in Figure 1 and closing the 6. jaws of the.clamshell work holder. Conversely, upon 7. retraction of the operating lever 80, the contacts of the 8. switch 93 are opened by the depression of the switch 9. actuating pin 90 thus opening the circuit to the drive motor 10. 67 and to the solenoid of the valve 96 which is spring 11. returned to a position in which it admits air under 12. compression from the supply line 97 to the pneumatic 13. cylinder assembly 35 forwardly of the piston 38 and exhausts 14. air from the cylinder assembly rearwardly of the piston, 15. thus interrupting operation of the drive motor and 16. retracting the piston rod 40 to move the jaws of the 17. clamshell work holder to the open position in which they are 18. shown in ghosted lines in Figure 1. 19. In operation, a work piece, the end of which is to 20. be machined first, is inserted between the open jaws of the 21. clamshell work holder in engagement and with the stock stop 22. 75 the stem 76 of which is pressed into contact with the 23. adjacent face of the front housing 14. The operating lever 24. 80 then is moved forwardly causing closure of the switch 93 25. to start the motor 67 and energize the solenoid of the valve 26. 96 to admit air under pressure to the pneumatic cylinder 27. assembly 35 and close the jaws of the clamshell work holder 1. on the inserted work piece. As the operating lever is moved 2. further forward, the machining tool 71 engages the clamped 3. work piece to apply the desired finish to it. The operating 4. lever 80 is then restored to its initial position against 5. the retraction stop 82, opening the circuit of the drive 6. motor and to % the solenoid of the valve 96 to stop the motor 7. and open the jaws of the clamshell work holder.

Claims: CLAIMS 1. A machine for finishing the ends of cylindrical work pieces comprising a housing, a spindle mounted in said housing for rotation and axial movement therein, means for mounting a machining tool on one end of said spindle, power operated means for rotating said spindle, a clamshell work holder means for clamping a work piece in position to be engaged by a tool mounted on said spindle including a first jaw fixed with respect to said housing adjacent said tool mounting means, a second jaw pivotally mounted on said housing, and power operated means for moving said jaws toward or away from each other to effect clamping or release of a work piece; and • means including a common control device f or controlling operation of said power operated means for rotating said spindle, and said power operated means for moving said jaws. 2. A machine according to claim 1 in which said common control device also controls axial movement of said spindle. 3. A machine according to claim 2 in which said common control device includes a manually operable member operatively connected to said spindle to effect positive movement thereof in the direction of said work holder means. 4. A machine according to claim 1 in which said power operated means for moving said jaws comprises a double acting pneumatic piston and cylinder assembly. 5. A machine according to claim 2 in which said power operated means for moving said jaws comprises a double acting pneumatic piston and cylinder assembly.

Inventors: BIRKESTRAND ORVILLE J, BIRKESTRAND, ORVILLE, J.
Applicants: BIRKESTRAND ORVILLE J, BIRKESTRAND, ORVILLE, J.
Application year: 1988
Main classification: B23B3
IPC codes: B23B5