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

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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

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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.