US3548700A

US3548700A - Punch holder and drive assembly

Info

Publication number: US3548700A
Authority: US
Inventors: John H Herzog; Ronald C Hill
Original assignee: Houdaille Industries Inc
Current assignee: Strippit Di Acro Houdaille Inc
Priority date: 1968-03-21
Filing date: 1968-03-21
Publication date: 1970-12-22
Anticipated expiration: 1987-12-22

Description

United States Patent .,62l,8ll 3/1927 Richard et a].

inventors John H. Herzog Clarence; Ronald C. Hill, Corfu, N.Y. Appl. No. 714,957 Filed Mar. 21, 1968 Patented Dec. 22, 1970 Assignee Houdaille industries, Inc.

Bul'lalo, N.Y. v a corporation of Delaware PUNCH HOLDER AND DRIVE ASSEMBLY 28 Claims, 13 Drawing Figs.

U.S. Cl. 83/698 526d 7/26 Field of Search 83/698 References Cited UNlT ED STATES PATENTS 2,107,581 2/l 938 Parsons et a1 83/698X 2,382,267 8/1945 Stellin 83/698X 2,622,682 l2/l 952 Kopczynski 83/698X FOREIGN PATENTS 600,087 6/1960 Canada 83/698 Primary Examiner-William S. Lawson Att0rneyHill, Sherman, Meroni, Gross and Simpson ABSTRACT: A punch holder and drive assembly for a press having a body which carries a gripping member which engages an attachment portion of a punch received in a socket of the -.-un 77 92 4a PUNCH HOLDER AN D DRIVE ASSEMBLY BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is directed to a punch holder and drive assembly particularly one which quickly engages a nested tool assembly comprising a die member, punch and stripper sleeve.

2. Prior Art In punch presses, a problem of performing rapid tool loading with a minimum amount of press-down time has arisen. I-Ieretofore, punch members were connected to the punch drive assembly by threaded fasteners which required considerable time to detach the punch member from the assembly.

SUMMARY OF THE INVENTION A punch holder and drive assembly includes a body means which has a socket for receiving an attachment portion of a punch and which carries gripping members to engage the portion to detachably interconnect the assembly and punch. The punch holder and drive assembly further includes lock means to maintain the gripping members in a normal locking position to maintain the connection between the punch and the punch holder and drive assembly. The lock means are selectively removable from the locking position and the gripping member 'may be moved to an unlocked position to allow the removal of the punch. The invention further includes a tool assembly comprising a punch with attachment means which is nestable in a stripper sleeve with the punch extending through an aperture of the stripper plate of the sleeve into the aperture of a die member to provide a single assembly which may be handled as a unit and loaded or unloaded from a press in a single operatron.

Accordingly, it is an object of the present invention to provide a punch holder and drive assembly which can be rapidly connected or disconnected from a punch for use in a press.

Another object of the present invention is to provide a punch holderand drive assembly of standard dimensions for use in a press and for connecting and supporting a tool assembly having standardized outer dimensions with interchangeable punches and dies of different cutting dimensions in the press.

A still further object of the present invention is to provide a tool assembly which can be loaded and unloaded in a press as a unit.

Yet another object of the present invention is to provide a construction which can be standardized as to external dimension for interchange with a similar construction having different cutting dimensions for the punch and die.

Many other advantages, novel features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description and accompanying sheets of drawings in which preferred structural embodiments incorporating the principles of the present invention are shown by way of illustrative examples.

On the drawings FIG. 1 is a fragmentary cross-sectiorral view of a punch holder and drive assembly constructed in accordance with the principles of the present invention disposed in a press yoke;

FIG. 2 is a fragmentary cross-sectional view taken on line II-II of FIG. 1;

FIG. 3 is a fragmentary cross-sectional view in enlarged scale of a modified form of a punch used with the punch holder and die assembly of FIG. 1;

FIG. 4 is a fragmentary cross-sectional view in enlarged scale of a third embodiment of the punch;

FIG. 5 is a fragmentary cross-sectional view of a modified fonn of the punch holder and drive assembly;

FIG. 6 is a fragmentary cross-sectional view of a third embodiment of the punch holder and drive assembly;

FIG. 7 is a view of a fourth embodiment of the punch holder and drive assembly;

FIG. 8 is a plan view of the punch holder and die assembly of FIG. 7;

FIG. 9 is a fragmentary cross-sectional view in enlarged scale of a modified form of the tool assembly illustrated in FIG. 7;

FIG. 10 is a fragmentary cross-sectional view of a third embodiment of the tool assembly;

FIG. 11 is a fragmentary cross-sectional view of a fifth embodiment of the punch holder and drive assembly disposed in a press; 7

FIG. 12 is a fragmentary cross-sectional view of a punch holder and die assembly similar to FIG. 11 at the completion of the punching stroke; and

FIG. 13 is a fragmentary cross-sectional view of the head portion of a punch holder and drive'assernbly illustrating a modification in a support detent.

As shown on the drawings The principles of the present invention are particularly useful in a punch holder and drive assembly generally indicated at 14 disposed in an upper tool support generally indicated at 15. The upper tool support 15 is comprised of a U-shaped yoke 16 having arms 16a, 16a interconnected by a bight portion 16b which supports a guide portion generallyjnd icated at 17 of the upper tool support structure 15.

The guide portion 17 includes a fixed annular sleeve 18 having a flange 19 which is received in a counterbored passageway 20 in the bight portion 16b and is secured therein by a screw 21. The sleeve 18 has an internal guide surface 22 having an axially extending groove 23. The guide portion 17 further includes a stripper sleeve support ring 25 having a counterbore 26 receiving a flanged end- 27 of a stripper sleeve 28. The flanged end 27 is held in the counterbore portion by a retainer means 29 which comprises a snap ring partially disposed in a groove formed in the counterbore 26.

The stripper sleeve 28 which is slidably received in the guide surface 22 has at the end 30 opposite theflanged end 27 a stripper plate 31 which has an aperture 32 detachably disposed in a counterbore 33 and held there by a retainer or a snap ring 34. The stripper sleeve 28 has an internal surface 35 which, in this embodiment has the samediameter as an internal surface 36 of the stripper support ring 25. The surface 35 has an axially extending groove 37 while the surface 36 has an aligned axially extending groove 38 and the two

surfaces

35 and 36 coact together to form a continuous inner guide surface 39 of the guide portion 17.

The punch holder and drive assembly '14 comprises a body means generally indicated at 40 which is made up of an upper body portion 41 and a lower body portion 42 which are interconnected by a number of threaded fastening means 43,43 which are illustrated as being machine screws. The

body portions

41 and 42 have a combined outer surface 44 which is slidably received in the inner guide surface 39 of the guide portion 17 to guide the punch holder and drive assembly 14 as it reciprocates in the punch press.

The upper body portion 41 has a head portion 45 having oppositely extending

flanges

46,46 which are provided for reception in a T-slot (not shown) of the ram of the punch press to reciprocate the punch holder and drive assembly 14 in the guide portion 17. The upper body portion 42 has an axially extending passageway 47 having a counterbore 48 at the head portion 45 and a counterbore 49 at the opposite end 50 to form an internal cavity when the lower body portion 43 is secured thereto. The outer surface 44a of the upper portion 41 has an annular groove 51 for receiving a holding means (not shown) to maintain the punch holder and drive assembly 14 in the upper position illustrated in FIG. 1 when the head portion 45 is detached from the ram of the press. I

The lower body portion 42 has a lower end surface 52 and prevent relative rotation between the punch holder and drive assembly 14 and the stripper sleeve 28 which in turn has a pin 59 received in the groove 23 to prevent rotation between sleeve 18 and stripper sleeve 28. The lower body portion 42 has an upper surface 57 with a cylindrical projection 58 which is received in the counterbore 49 of the upper body portion 41 as the surface 57 engages the lower end surface 50. Extending upwardly from the projection 58 is a second projection 60 having a plurality. of passageways 61 best seen in FIG. 2. Disposed in each passageway 61 is a gripping member 62 which is illustrated to. be a ball. The gripping member 62 is movable in the passageway 61 between a normal locking position in which the ball extends into the passageway 53 and an unlocked position in which the ball is retracted in the passageway 61 so as to be clear of the passageway 53. A resilient means 63 which comprises a snap ring is disposed about the projection 60 to urge or bias the gripping members 62 toward the normal locking position. To hold or maintain the gripping member 62 in the normal locking position, a locking means generally indicated at 64 is disposed in the upper body portion 41. g

- The punch holder and drive assembly 14 is detachably connected to an attachment portion 65 of a punch 66 by the gripping members 62 engaging a neck or annular groove portion 67 of the attachment portion 65. The punch 66 has a body portion 68 having a punch tip 69 and an upper surface 71. The body portion 68 has an upper cylindrical projection 72 which as illustrated has a threaded bore 73 to receive a threaded end 74 of the attachment portion 65 to connect the attachment portion 65 to the body portion 68. As the punch 66 is connected to the punch holder and drive assembly 14, the projection 72 is received in the counterbore 54 as the attachment portion 65 is received in the passageway 53. The engagement between the surfaces of the attachment portion 65 and the projection 72 with the locating surfaces formed by the

passageways

53 and 54 axially align the punch 66 with the punch holder and drive assembly 14. The upper surface 71 of the punch body 68 is provided with a pin 75 which is received in the groove 55 to prevent relative rotation between the punch 66 and the punch holder and drive assembly 14.

As best illustrated in FlG. 2, the lock means 64 comprises a lock member 76, a stop means generally indicated at 77 and a spring 78. The lock member 76 has a stem portion 79 and a head or cage 81 at one end. The head 8l has an internally directedfrustoconical cam surface 82 which engages each gripping member 62 to urge and maintain it in the normal locking position as illustrated.

The lock member 76 is supported in the upper body portion 41 with. the stem 79' being slideably disposed in the passageway 47 and the head 81 being freely disposed in the counterbore 49. The locking member 76 is reciprocable between a first position illustrated in the FIGS. in which the cam surface 82 holds or maintains the gripping members 62 in engagement with the neck 67 of attachment portion 65 and a second position in which the head 81 is moved upwardly in the counterbore 49 to allow an outward movement of the gripping members 62 to the unlocked position. The other end of the stem 79 has a annular ring 83 which is either force fitted or threaded thereon. The annular ring 83 has a lower abutment 84 on which the spring 78 disposed in the counterbore 48 acts to bias or move the lock member 76 toward the second position.

To prevent the lock member 76 from moving to the second position, the stop means 77 has a pin 85 which is disposed in a passageway 86 which extends transversely to the direction of reciprocation of the lock member 79. The passageway 86 has a plastic bearing 87 which slideably receives a stem portion 88 of the pin 85. A spring 89 is disposed about the stem portion 88 to urge the pin 85 into engagement with an abutment or shoulder 90 formed by a groove 91 in the stem 79 of the lock member 76. The stem portion 88 terminates in a knob 92 which enables the pin 85 to be manually moved out of engagement with the shoulder 90 to permit the lock member 76 to move to the second position.

As illustrated the gripping members 62 are held in the lock position by a resilient means 63, and thus will not disengage the attachment portion 65 of the punch 66 even when the lock member 76 is in the second position. To remove the punch 66 from the punch holder and drive assembly 14, the

body portions

42, 43 are provided with a pair' of angularly extending

passageways

95, 95 and the stem 79 of the lock member 76 is provided with an axially extending passageway 96. Once the lock member 76 is moved to the second position, a rod or pin may be inserted through one of the

passageways

95,95, or 96 to tap the punch 66 to move the gripping member 62 against the resilient means 63 a to allow the withdrawal or ejection of the punch 66.

To insert a, punch 66 into the punchholder and drive assembly 14, the stop means 77 is disengaged from the shoulder 90 to allow the lock member 76 to move to the second position freeing the gripping member 62. The punch 66 is then inserted with the the attachment portion 65 being positioned in the passageway 53 and with the pin 75 in alignment with the groove 55. Upward movement of the punch 66 until the surface 52 is in contact with the surface 71 of the punch will force the gripping members 62 outwardly against the resilient means 63. When the neck 67 of the attachment portion 65 is aligned with the gripping member 62, the resilient means 63 urges the gripping member into the neck to temporarily hold the punch 66 in place. Then by applying pressure to the outer end of the stem 79 against the force of the spring 78, the lock member 76 is moved to the first position and the spring 89 will move the pin of the stop means 77 into contact and engagement with the shoulder 90. It should be noted that the outer end 93 of the stem 79 is flush with an upper surface 97 of the head portion 45 of the body portion 41 of the body means 40 so that a punch ram may be used to force the lock member 76 to the first position against the pressure of the spring 78. However, normally when the lock member is in its outer unlocked position, it projects and prevents reception of the T-head portion into a T-slotted ram until positive locking has been effected.

FIGS. 3 and 4 illustrate differentsize punches 66a and 66b respectively used with the punch holder and drive assembly 14. In FIG. 3 a punch 66a has a body portion 68a which has a punch cutting edge 69a at one end and an upper surface 71a at the opposite end. The body portion 680 has a cylindrical upwardly extending projection 72a which is received in the socket formed by the counterbore 54in the lower body portion 42 of the punch holder and drive assembly 14. The projection 7211 has a threaded bore 73a for receiving a threaded end 74 of the attachment portion 65 of the punch an and an upper surface 100 which abuts against a shoulder 54a formed by the counterbore 54 in the body portion 42. To prevent axial rotation between the assembly 14 and the punch member 66a, a pin 75a which is disposed in a radial bore in the projection 73a is engaged in the groove 55 of the-lower body portion 42. While secured in the punch holder and drive assembly 14, the punch 66a has surfaced 71a and 100 engaging the

surfaces

52 and 54a respectively to transmit the punching force from the assembly 14 to the punch. The stripper sleeve 280 has a stripper plate 31a disposed in a counterbore 33 and held there by the retaining means 34. The stripper plate 31a has an aperture 32a which is complementary to the punch cutting edge 69a.

As shown in FIG. 4, the punch 66b is of a smaller size than the punch 66a. The punch 66b has a body portion 68b which has a cutting edge 69b at one end and an upper body portion 72b at the other end. The upper body portion 72b is cylindrical and is received in the counterbore 54 with an upper surface 100b in engagement with the shoulder 54a. The upper portion 72b has a threaded bore 73b which has a threaded projection 74 of the attachment portion 65 threadedly engaged therein. To prevent relative rotation, a pin 75b is threaded into the upper portion 72b and coacts with the groove 55 of the lower body portion 42. Punching forces are applied to the upper surface 10%.

The stripper sleeve 28 has a first stripper plate 31b disposed at one end in the counterbore 33 and held there by the 76a, either by hand or by useofThe ram 116, the lock member 76a is moved to the first position allowing the pin 85a of the stop means 77a to engage the abutment 900. When the lock member 76a is in the first position, the gripping member 620 I forms a positive connection between the punch 66c and the punch holder and drive assembly 14a.

FIG. 6 illustrates a third embodiment of the punch holder and drive assembly generally indicated at 1412, disposed in :1

wrench flats 168 and has a head 169 defined by a neck 171.

station or guide portion 130 of an upper turret 131 of a press I generally indicated at 15b. The turret 131 has a plurality of stations or guide portions 130 each of which is comprised of a sleeve 132 disposed in a bore 133 of the turret 131. The sleeve 132 has an axially extending groove 134 and an upper flange 135 having an upwardly directed edge or surface 136.

The punch holder and drive assembly 14b has a body means generally indicated at b which has an upper body portion 41b and a lower body portion 42b. The body portions 41b and 42b are held together by a plurality of machine screws 43b to form an outer surface 44b of the body means 40b. To prevent relative rotation between the assembly 14b and the guide portion 130, the outer surface 44b has a pin 56b engaged in the groove 134.

The upper body portion 41b has a head portion 45b which has a transversely extending T-shaped groove or slot 137 for receiving in one turret position a complementary head of a press ram (not shown) and for alternatively receiving an unloading ram 138 in another turret position. The head portion 142 are trapped in a bore 143 which is closed at one end by a threaded plug 144, and which is of converging size at the other end.

The upper body portion 41b has an axially extending passageway 47b havinga counterbore 48b adjacent to the T- slot 137 and a second counterbore 49b extending inwardly froma lower end surface 50b.

The body portion 42b has an axially extending passageway 53b having a counterbore 54b extending inwardly from a lower end surface 52b to define a socket. A radial slot 55b in the lower end surface 52b extends outwardly from the counterbore 54b. The passageway 53b and the counterbore 54b have an internal shoulder 145 which is the base of the counterbore 54b. The lower body portion 42b has an upper surface l57b which has a cylindrical concentric projection 58b extending upwardly therefrom to be received in the counterbore 49b as the two body portions 41 41b and 42b are joined together. The projection 58b has a second projection 60b hav ing passageways 61b extending transversely to the direction of reciprocation of the punch holder and die assembly 14b. Each of the passageways 61b contains a gripping means 62b which is illustrated as a ball. A resilient means such as a snap ring 63b urges the balls inwardly toward a normal locking position.

The punch holder and drive assembly 14b cooperates with a nestable tool assembly generally indicated at 146. The nestable tool assembly 146 comprises a punch 147, a stripper sleeve 148, an apertured die member 149 and a spacer plate 151. The punch 147 has a punch body 152, a cutting end 153 and an upper portion 154. The upper portion 154 has a retainer 155, namely-a snap ring disposed in a groove, and a locating pin 150 which is received in the groove 55b to prevent relative rotation between the punch 147 and the assembly 14b.

The stripper sleeve 148 at one end has a counterbore 156 in which a stripper plate 157 having an aperture 158 complementary to the cutting end 153 is disposed and hold by a retaining means 159, namely a snap ring, disposed in grooves of both the stripper plate 157 and the wall of the-counterbore 156. The stripper sleeve 148 at an end opposite the counterbore 156 has a retainer 161 which comprises-an inwardly ex tending flange. The spacer plate 151 has an aperture 162 which is received on the upper portion 154 of the punch 147. The spacer plate 151 has an upper surface 163 and a-lower The tool assembly 146 is connected to the punch holder and drive assembly 14b by the attachment portion 167 being inserted into the passageway 53b and having its neck 171 engaged by the gripping member 62b. When the tool assembly 0 146 is connected to the punch holder arid drive assembly 14b,

bore 175 in the ram 138 and the ram 138 carries an ejection the upper portion 154 engages a lobating surface defined by the counterbore 54b. The body means 50 40b is providedwith a plurality of passageways 172 adjacent the outer surface 44b which contain a plurality of stripper pin rods 173 which act against the stripper a sleeve 148 to force the sleeve into contact with the workpiece during the punching operation.

To maintain the gripping member 62b in firm engagement with the neck 17] of the attachment portior 167, a locking means generally indicated at 64b is disposed in the body means 40bb. The locking means 64b include a lock member 76b, a stop means 77b and a spring 7817. The lock member 76b has a stem 79b and a head or cage 81b which has an inwardly directed cam surface 82b which engages and holds the gripping members 62b in the normal locking position as the lock member 76b assumes a first position illustrated in the FIG. When the lock member 76b moves to a second position the cam surfaces 82b are moved out of contact with the gripping members 62b. The stem 79b is provided on the end opposite the head 81b with a ring 83b and the spring 78b which is disposed in the counterbore 485 contacts the ring 8317 to urge the lock member 76b toward the second position. Only the unloading ram 138 has a hollowed out portion 174 to provide clearance for the head 83b the lock member 76b moves to the second position. The stem 79b is provided with an axially extending bore 961: which is axially aligned with a pin 176 which is moved in the bore 175 to enter the bore 96b.

The stop' means 77b comprises a pin 177 preferably of rectangular cross section which is slidably disposed in a corresponding transversely extending passageway 178. The passageway 178 has a counterbore portion 179 adjacent the outer surface 44b. The pin 177 has an enlarged head 181 slidably disposed in the counterbore 179 and is biased toward the guide portion 130 by a spring 182. The pin 177 engages a shoulder or abutment 90b formed by a groove 91b in the stern 79b to hold the lock member 76b in the first position; The guide portion 130 is provided with a depression or groove 183 which will receive the enlarged head 181 when the punch holder and drive assembly 14b is axially moved within the station 130 until thedepression 183 andthe counterbore 179 are aligned. When the alignment which defines an unloading/loading position for the punch holder and drive assembly 14b is obtained, the head 181 moves into the depression to withdraw the pin 177 from the engagement with the shoulder 90b to allow the lock member 76b to move to the second position. Both the pin 177 and the head 181 are provided with cam :nds or surfaces 184 and 185 respectively. The cam surface acts against an edge of the depression 183 to bias the head 181 against the spring 182 to force the pin 177 into engagement with the abutment or shoulder b. During the cam ac- I tion of the cam surface l8 5, the cam surface 1840f the pin 177 acts against the shoulder 90b to force the lock member- I 65 76b against the spring 78b to the first position. Thus, the upmovement in the opposite direction automatically effects un- 70 locking.

During a punching operation the punch holder and drive assembly 14b is reciprocated in the guide portion 'by a punching ram having a T-head similar to the ram 138. During t reciprocation the surface transfers the punching force to surface 164 which act as abutment surfaces for engaging the 75 the upper surface of the punch- 157 to force the punch into enretainer means 34. The stripper plate 31b has an aperture 3211 which is substantially larger than the punch 66b. The aperture 32b has a shoulder 101 formed by a counterbore which receives a second stripper plate 102 which has an aperture 103 complementary to the cutting edge 69b of the punch 66b. The second stripper plate 102 is held in the counterbore against the shoulder 101 by a retaining means or ring 104 to form a combined stripper plate 105. The advantages of the combined stripper plate 105 are that is saves material when providing a small aperture such as 103 for a small punch 66b and that it allows the formation of a stripper plate which can be adapted to handle punch tips of any size up to the size of the aperture 3212.

FIG. 5 illustrates a second form or embodiment of the punch holder and drive assembly generally indicated at 14a disposed in an upper tool support indicated at 15, having a bight portion 16b and shown more fully in F IG. 1. The bight portion 16b supports a guide portion generally indicated at 17a of the upper tool support 15. The guide portion 17a includes a fixed annular sleeve 18 which is received and secured in a passageway 20 by a series of screws 21. The sleeve 18 has an internal guide surface 22 having an an axially extending groove 23. The guide portion 170 further includes a stripper sleeve 28a having a flange 27a and has a radially extending pin 59a engaged in the groove 23 to prevent rotation between the stripper sleeve 28a and the annular sleeve 18. The stripper sleeve 28a is interconnected with an annular ring 106 by an axial lost-motion connection 107 which comprises a series of bolts 108 threaded into the flange 27a and a like number of stripping springs 109 which are telescopically received on the bolts 108 and extend between the ring 106 and the flange 27a. The springs 109 urge the stripper sleeve 28a away from the ring 106 which in turn is urged away from the upper surface 111 of the bight portion 16a by a plurality of lifter springs 112 each of which bears on a pin 113 disposed in a bore 114 of the ring 106.

The stripper sleeve 28a at an end opposite the flange 27a has an end 30a and has an internal surface a which forms the internal guide surface of the guide portion 17a. The surface 35a is provided with an axially extending groove 37a.

The punch holder and drive assembly 14a includes a body means generally indicated at 400 which has an upper portion 41a and a lower portion 42a which are interconnected by a number of threaded fasteners such as bolts 43a. The upper body portion 41a has an upper surface 115 which is contacted by a ram 116 of the punch press to apply the reciprocal motion to the punch holder and drive assembly 14a. The upper portion is also provided with an annular flange 117 which supports the assembly 140 on the ring 106. The upper body portion 41a has an axial passageway 470 having a counterbore 48a extending inwardly from the surface 115 and a counterbore 490 extending inwardly from a lower end surface 50 50a.

The lower body portion 42a has a socket defined by a passageway 530 having a counterbore 54a extending inwardly from a lower surface 52a which has a radial groove 55a extending into the counterbore 54a. Extending outwardly from the lower body portion 420 is a radial pin 56a which is received in the groove 37a of the stripper sleeve 28a to prevent relative rotation between the punch holder and drive assembly 14a and the stripper sleeve 28a.'The lower body portion 42a has an upper surface 570 having a cylindrical projection 58a which is disposed in the counterbore 49a as the surface 570 engages the lower surface 50a of the upper body portion 410. The projection 580 has a second projection 60a having passageways 61a extending transversely to the passageway 53a and to the direction of reciprocation of the body means 40a. Gripping means 620 comprising balls are disposed in the passageway 61a and are movable from a normal locking position, in which the balls are projecting into the passageway 53a,

- to an unlocked position in which the balls are withdrawn into the passageway 61a to be clear of the passageway 53a.

Disposed about the second projection 60 is a resilient means 63a comprising a snap ring which biases the gripping member 620 toward the normal locking position.

A lock means generally indicated at 640 engages the gripping means 62a to maintain them in the normal locking position to engage the neck portion 67 of the attachment portion 65 of a punch 660. The punch 660 has a body portion 680 having a cylindrical projection 72c which is received in the counterbore 54a and has a pin 75c mounted in a bore and received in the groove 55a to prevent relative rotation between the punch 66c and the-punch holder and drive assembly 14a. The punch 66c has an upper surface 710 contacting the surface 52a as an upper surface 1000 is received in the base of the counterbore 54a.

The lock means 640 has a lock member 76a which is essentially the same as the precedingly described lock member 76. The lock member 760 is movable between a first and a second position and is urged toward the second position by a spring 78a. A stop means generally indicated at #70 holds the lock member 76a in the first position. A shoulder or abutment 90a is provided by the upper surface of thehead or cage 810 which has an internally directed cam surface 82a.

The stop means 77a has a pin 85 a whichengages the abutment or shoulder a to maintain the lock member 76a in the first position to maintain the gripping member 62a in the normal locking position. The pin 85a is disposed in a bore 86a and is attached to an enlarged block which is movable in a passageway 121 leading to the bore 86a. A spring 89a acting between a threaded plug 122 and the block 121 urges the stop means 77a into engagement with the abutment 90a. A second pin 123 extends at a right angle to the pin 85a through a slot 124 and is threaded into the block 120. The pin 123 terminates below the upper surface 115 and therefore is not engaged by the ram 116 when the ram is in contact with the punch holder and drive assembly 14a. By manual movement of the pin 123 in a radially outward direction, the pin 85a is disengaged from the shoulder 90a, thereby allowing the lock member 760 to move to a second position in which the cam surfaces 82a are withdrawn from contact with the gripping member 62a.

In operation, the punch holder and drive assembly is supported in the upward position, as illustrated, by the lifting springs 112. When the ram 116 contacts the surface 115 and reciprocates the punch holder and drive assembly 144 downwardly, the springs 112 are compressed. The spring 109 forces the stripper sleeve 28a into contact with the workpiece and once contact is made, the spring 109 begins to be compressed until the end of the downward stroke. Upon upward movement of the ram 116, the stripper springs 109 maintain the stripper sleeve 28a in contact with the workpiece until the punch 660 is withdrawn therefrom.

When the head of the bolt 108 contacts or abuts against the ring 107, the sleeve 28a is carried with the punch holder and drive assembly 14a by the lifter springs 112 to the position illustrated.

To release the punch 66c from the punch holder and drive assembly 140, the stop means 77a is disengaged by forcing the second pin 123 radially outwardly from the position illustrated to withdraw the pin 85a from engagement with the abutment 90a to allow the lock member 76a to move to the second position. Although the lock member 76a is in the second position, the gripping members 62a are yieldably held in the normal locking position by the force of the resilient means 63a. Any force which is applied to the punch 660, such as by a rod (not shown) being pushed down through a passageway 96a in the stem 79a, will move the attachment portion 65 out of engagement with the gripping member 62a.

To load a punch 66c into the punch holder and drive assembly 14a, the lock member 76a must be in the second position. Insertion and movement of an attachment portion 65 into the passageway 53a and past the gripping means or balls 62a forces the balls to the unlocked'position until the neck portions 67 become aligned with the passageway 61a. Then the resilient means 63a will urge the gripping members 62a into the normal locking position and temporarily hold the punch 66c in the punch holder and drive assembly 14a. By applying a force to the upper surface 97a of the lock member with the workpiece to grip the workpiece between the stripper sleeve 145 and the die member 149. The stripper sleeve 145 also is held in contact with the workpiece by the stripper pins 173, while the punch 157 is withdrawn from the workpiece. As the punch 157 is moved upwardly, the upper surface 163 of the spacer plate 151 contacts the retainer 161 and draws the stripper sleeve 148 back into'the guide portionor station 130 of the turret 131. v i

To unload the tool assembly 146 from the punch holder and I drive assembly 14b, the turret 131 is angularly rotated from beneath the punching ram to the unloading/loading station and the unloading/loading ram 138 is engaged in the T-shaped slot 137 of the head portion 45b of the assembly 14b. The ram 138 then vertically moves the die holder and punching assembly 14b to the unloading/loading positiorrwith the counterbore 179 in alignment with the depression or groove 183. Upon reaching'the unloading/loading position, the spring 182 forces the stop means 77b to the disengagement position to allow the lock member 76b to move to' the second position to enable the gripping members 62b to be moved to the unlocked I position. Once the lock member 76b is in the second position, the ejection pin 176 carried by the ram 138 moves through the passageway 96b to contact the head 169.tof the attachment portion 167 to force the head past the gripping members 62b. By applying a force to the head portion 169, the gripping members 62b are cammed outwardly by the curvature of the neck portion 171 to the unlocked position and the tool assembly 146 is removed from the station 130. It should be noted that when lowering the punch holder and drive as sembly 14b to the unloadinglloading position, the stripper sleeve has contacted the die member 149 andhas moved it in its station in the lower turret. The punch press is provided with a mechanical means (not shown) to catch the nested tool assembly 146, which assembly may be also received by hand.

To load a tool assembly such as 146, the tool assembly is lifted through the station in the lower'turret with the pin 150 aligned with the groove 55b until the attachment portion 167 is received in the bore 53b of the punch holder and drive assembly 1417. By continuing the upwardly lifting of the tool assembly, the head 169 contacts the gripping members 62b forcing them to the unlocked position to allow passageofthe head 169 until the neck portion 171 is in alignment with the gripping members 62b which are then urged by the spring 63b into temporary engagement with the attachment portion 167. Once the temporary connection has been completed, the

punch holder and drive assembly 14b is moved upwardly from the unloading/loading position and the cam surface 185,

coacting with the depression 183, forces the pin 177 of the lock means 77b into engagement with the shoulder 90b to force the lock member 76b to the first position to lock the gripping members 62b in contact with the attachment portion 167 of the tool assembly 146. When the punch holder and drive assembly 14b is moved to the position illustrated in FIG. 6, the detent 139 engages the upwardly directed surface 136 of the 139.or guide portion 130 and holds the punch holder and drive assembly in thisposition while .the turret 131 is rotated to remove the station 130 from beneath the load ing/unloading ram 138. It should be noted that the detent 139 will yield in response to a force applied to the punch holder and drive assembly 14b by any one of the rains and functions to hold the assembly 14b while it is being rotated away from a position where it receives ramsupport. I

FIG. 7 illustrates a fourth modification of a punch holder and drive assembly generally indicated at 14c disposed in a station or guide portion 130a of an upper turret 131a of a punch press generally indicated at 150. The guide portion 130a comprises an inner surface of a sleeve 132a disposed in the bore 133a of the turret 131a. The sleeve 132a has'an axial groove 143a extending a portion of the axial length of the sleeve 132a.

The punch holder and drive assembly 140 comprises a body means generally indicated at 400 which is a one-piece member having a head portion 450 which has a T-shaped slot 137a for reception and engagement with a punching mm or an unloadsembly 140 has a lower surface 52c which has a socket 191 defined by a'passageway 192 extendingaxially inwardly from the surface 52c. The passageway 192 has a first counterbore 193 and a second counterbore 194. hr communication with the passageway 192 is an ejection pin passageway 195 which has a countersunk portion 196 adjacent the T-shaped slot The body means 400 has a passageway 197 extending-transversely to the passageway 192 and to the direction of reciprocation of the punch holder and drive assemb1y14c. In each of the passageways 197 is disposeda gripping member 62c, illustrated to be a ball, and a lock means'generally indicated at 64c. The passageway 197 is provided with an inwardly extending retainer lip 198 adjacent to the passageway 192 to limit the inward movement of the gripping means 620 to a normal locking position. y I

The lock means 640 comprises a shaft or pm 199 slidably disposed in the passageway 197. The shaft 199 has an end surface 201 which is concave and is in contact withthe gripping member 62c. Each end 201 has a bore 202 which receives a spring 203 which urges the gripping member and the end surface 201 apart. At an end opposite to the end 201, the shaft 199 has a cage 204 holding 'a ball follower 205. The passageway 197 has a counterbore 206 adjacent the outer surface 440 to receive the cage 204. y v

The guide portion 1300 has a depression or groove 1830 which receives the ball follower 205 when the punch holder and drive assembly 140 are loweredto a loading/unloading position. When the ball follower 205 i s-re ceived in the depression 183a, the gripping means 620 is still resiliently urged or biased by the spring 203 to the normal locking position.

The punch holder and drive assembly 14c c'oact with a nestable tool assembly 146awhich has a punch 147a, a stripper sleeve 148a, a die 149a and a spacer plate 151a. The punch 147a has a body portion 1521: having a cutting end 153a and an upper portion 154a which is cylindrical and is received in the counterbore 193 The spacer plate 151a has an aperture 162a which is disposed around Ethe projection 154a, the plate resting on a shoulder 207 formed by the projection 154a and the body portion 152. The shoulder 207.acts as a lower retainer for the spacer plate 151a and a second or upper retainer 208 is provided to prevent the plate from being removed from the punch 147a. .Whenthepunch 147a is connected to the assembly 140, the second counterbore 194 receives the upper retainer 208 and provides a clearance so that the retainer 208 does not receive any of the punching force of the assembly'14c. The punch 147a is provided with a locating pin 150a extending through a branch of the aperture 162a into a groove 550 in the lower surface'52c of the body means 40c to prevent relative rotation of the punch 147a and the assembly 14c. The upper portion 154a has a threaded socket 211 receiving a threaded projection 212 of an attachment portion 213. The attachment portion 213 at the opposite end from the threaded projection 212 has a head por tion 214 which is defined by a neck 215. The attachment portion 213 and upper portion 154 are received in locating surfaces defined by the passageway 192 and counterbore 193 of the body means 400, and the attachment portion 213 forms a connection between the tool assembly 146a and the punch holder and drive assembly 14c when the neck 215 is engaged by the gripping means 620.

The stripper sleeve 148a of the tool assembly 146a has a counterbore 156a at one end receiving a stripper plate 157a which has an aperture 158a which is complementary to the cutting end 153a of the punch. The stripper plate 157a is retained in the counterbore by a retainer 159a comprising a grip or clip secured to the stripper sleeve 148a by a screw. At the end opposite the counterbore 156a, the stripper sleeve 1480 has a retainer 161a which is an inwardly extending flange. An upper surface 163a of the spacer plate 151a contacts the retainer 161a and prevents the withdrawal of the punch 147a past the end opposite the counterbore 156a.

During the punching operation, a punch ram is engaged in the slot 137a of the punchholder and drive assembly 140 to reciprocate the assembly in the guide portion 130a. The punching force is transferred from the assembly 140 to the punch 147a through the surfaces 52c to the spacer plate 151a and then to the punch body 152a. During the downward stroke of the punching ram, the stripper-pins 173a are urged downward by means (not shown) to force the stripper sleeve 148a into engagement with a workpiece and to clamp the workpiece between the stripper sleeve 148a and the die member 149a. Continuation of movement of the punch holder and drive assembly 14c causes the punch end 153a to penetrate the workpiece to perform the desired operation. As the punching ram completes its downward movement and starts its upward movement, the punch end 153a is withdrawn from the workpiece while the stripper pins 173a maintain the stripper plate 157a in engagement with the workpiece to assist the stripping of the punch end 153a from the workpiece. As the punch 147a is withdrawn, the upper surface 163a of the spacer plate 151a contacts the retainer 161a and carries the stripper sleeve 148a with the punch 147a back into the station 130a to the position illustrated.

To remove the tool assembly 146:: from the punch holder and drive assembly 140, the turret 131a is rotated until the assembly 14c in the station 130a is positioned beneath a loading/unloading ram similar to the ram 138 illustrated in FIG. 6. The unloading/loading ram lowers the punch holder and drive assembly 14c to the unloading/loading position in which the ball followers 205 may enter the depressions 183a in the guide portion 130a. This movement of the ball follower removes the positive locking of the gripping means 62c by the lock means 640. Next, an ejection pin similar to the pin 176 moves through the ejection pin bore 195 to apply force to the head 214 of the attachment portion 213 of the punch 1470. In response to such force, the surfaces of the neck 215 cam or move the gripping members 620 against the springs 203 to an unlocked position which allows the passage of the head 214 past the gripping members 62c. When the punch holder and drive assembly 14c is lowered to the unloading/loading position, the movement causes the die member 149a to be removed from the holding means of the lower turret so that once attachment portion 213 of the punch 147a is disconnected from the punch holder and drive assembly 140, the nested tool assembly 146a can be removed through the station of the lower turret.

To insert a tool assembly 146a, the tool assembly is lifted through the station of the lower turret until the attachment portion 213 is positioned in the passageway or bore 192. Continuation of lifting of the tool assembly causes the head 214 to contact the gripping members 620 and move them against the springs 203 to the unlocked position until the neck 215 is in alignment with the passageways 197. At that time, the springs 203 bias the gripping members 620 into a temporary connection with the attachment portion 213. Once the tool assembly 146a has been temporarily connected to the punch holder and drive assembly 146, the ram of the unloading/loading station moves upwardly causing the cam followers 205 to be withdrawn from the depression 183a and to move the locking means 64c into contact with the gripping members 62c to maintain them in the normal locking position.

FIG. 9 illustrates a modified form of the tool assembly generally indicated at 14612, held in a punch holder and drive assembly generally indicated at 140. The tool assembly 1415b comprises a punch 147b, a stripper plate 14812, and a spacer plate 151k. The die associated with the tool assembly 146b is not illustrated but is similar to die members-149 and 149a.

The punch 147b has a punch body 15212 having a cutting edge 15312 at one end and an upper portion 154b at the other end. The upper portion 154b and the body portion 152b form a shoulder 207a which acts as a lower retainer which coacts with an upper retainer 208a to hold the spacer plate 151b in a locked position on the punch .147b. The upper portion 154b has a pin 15% extending outwardly and engaged in the groove 55c to prevent rotation between the punch 14% and the punch holder and drive assembly 14c.

The stripper sleeve 148b at one end has a counterbore 15612 receiving a stripper plate 15712 having an aperture 15812 which is complementary to the punch end 153b. The stripper plate 15712 is held in the counterbore by a retainer clip 15% secured by a screw to the stripper sleeve 148b. The stripper sleeve 14812 at an end opposite the counterbore 15612 has an inwardly extending flange or retainer 161k;

The spacer plate 151b has an upper surface 163b and a lower surface 164b which act as abutments for engaging the retainer 16112 and the stripper sleeve 15712 to form an axial lost-motion connection generally indicated at 211 which prevents the removal of the punch 147b from the stripper sleeve 14812. The spacer plate 151b also has an aperture 162b which allows the positioning of the spacer plate about the projection 15412.

When the punch holder and drive assembly 14c is driving the punch 14712 into a workpiece, the punching force is transmitted by the lower end surfaces 520 to an upper surface 163b of the spacer plate 151 which in turn transfers the force to the punch 14712. Force is also transmitted by a shoulder 221 to an upper surface 222 of the punch 147b. The second counterbore 194 provides space to receive the upper retainer 208a when the tool assembly 146b is connected to the punch holder and drive assembly 14c.

FIG. 10 illustrates a nestable tool assembly generally indicated at 146C attached to a punch holder and drive assembly 14c, both of which are disposed in a guide portion a formed by a sleeve 132a disposed in an upper turret 131a of a punch press.

The tool assembly 146C comprises a punch 1470, a stripper sleeve 1480, and a spacer plate l51c. The die which is similar to the die 149 is not illustrated. The punch 147a has a punch body '152c terminating in a punch end'l53c at one end and having an upper portion 1540 at the other end. The upper portion 1546 has a pair of retainers 208a and 225 which maintain the spacer plate l51c in position on the upper portion 1570. The upper portion 157a is also provided with a pin 1506 which is received in the groove 55c of the punch holder and drive assembly to prevent relative rotation therebetween. The spacer plate l5lchas an upper surface 163c and a lower surface 164a which form abutments which coact with the retainers 208C and 225 to maintain the plate in its fixed position with an aperture 1620 disposed about the punch member 1470.

The stripper sleeve 148:: has a counterbore 1'56c adjacent to one end which receives a stripper plate l57c having an aperture 158c complementary to the punch end 1531:. The stripper plate 157C is held in the counterbore 156:: by a retaining clip 1590 fastened by a screw to the stripper sleeve 1480. The stripper sleeve 148a at the other end has an inwardly extending retainer flange 1610.

An'axial lost-motion connection generally indicated at 211C is formed by the coaction of an abutment 226 of the punchcounterbore 193 with an upper surface 222a in contact with the shoulder or bottom 221 and the upper retainer 2086 is received in the second counterbore 194. The punching force of the punch holder and drive assembly is transmitted by the surface 221 to the upper surface 222:: to drive the punch into the workpiece. The spacer plate HR is of a thickness such that the upper surface 163C is not in contact with the lower end surface 520 of the punch holder and drive assembly 140 and therefore doesnt receive any of the punching force.

FIGS. 11 and 12 illustrate a fifth embodiment of the punch holder and drive assembly generally indicated at 14d used in conjunction in a punch press generally indicated at 15d, which has an upper turret 231 and a lower turret 232.

The upper turret 231 has a plurality of stations or guide portions 233 which comprise an annular sleeve 234 disposed in a bore 235 of the upper turret. The sleeve 234 has an annular extending flange 236 which is received in a counterbore 237 of the bore 235. The lower end portion'of the sleeve 234 has a threaded portion 238 on which a'hub nut 239 is threadedly engaged and received in a lower counterbore 241. The hub nut 239 maintains the sleeve 234 in a fixed relationship within the bore 235 of the upper turret 231. On an end opposite the threaded end 238 the sleeve 234 has a layerpr cushion 242 of resilient material. The inner surface of thesleeve 234 which defines the guide portion or station 233 is divided into a lower cylindrical surface 243 and an upper cylindrical surface 244 which are interconnected by a shoulder 245. The lower surface 243 has an axially extending groove 246-.

The lower turret 232 illustrated in FIG. 12 has a plurality of lower stations which are defined by a number of bores 247. Each of the lower stations has a ball detent 248 in a surface of the bore.

The punch holder and drive assembly l4dhas a body means generally indicated at 251 comprising an inner body portion 252 having an outer surface 253 which is engaged by an inner surface 254 of an annular sleeve 255. The body portion 252 has a head portion 256 which has a greater diameter than the outer surface 253. The head portion 256 has a T-shaped slot 257 which is connectable with a T-shaped end 258, of a punch ram 259. The head portion 256 has a pair of axially extending

bores

261, 261 each of which has a counterbore 262. A pair of pins 263 having heads 264 are slidably received within the bores 261 with the head received in the counterbore 262 and the end opposite the head 264 being threadedly engaged in a flange 265 of the sleeve 255 to form a lost motion connection generally indicated at 266 between the'sleeve 255 and the body portion 252. Y

The punch ram 259 has a pair of bores 267, 267 which are in axial alignment with the bores 261,261. Each of the bores 267 has a piston or spacer 268 slidably received and retained therein and urged by resilient means 269 such as a spring into contact with the head 264 of the pin 263. The springs 269 acting through the

pins

263, 263 urge the sleeve 255 axially away from the head portion 256 of the inner body portion 252.

The body portion 252 opposite the head portion 256 has a reduced diameter end portion 271 having anend surface 272. The body portion 252 has an axially extending passageway 273 having a counterbore 274 extending inwardly from the end surface 272 to fonn a socket for receiving an attachment portion 275 of the punch 276. The body portion 252 has a pair of passageways 61d which extend transversely to the counterbore 274 and to the direction of reciprocation of the punch holder and drive assembly 14d. The passageways 61d extend to the outer surface 253 of the body portion'252 and each passageway has a gripping ball member 62d disposed therein.

The sleeve 255 has an outer surface 277 which is slidably engaged in the upper inner surface 244 of the station 233 to guide the punch holder and drive assembly 14:1. The sleeve 255 adjacent the other end 278 is provided with a pair of passageways or

depressions

279, 279 which extend transversely to the direction of reciprocation of the punch holder and drive assembly 14d. The passageways or depressions 279 each have a plug 280 of resilient material disposed therein.

The punch holder and drive assembly 14d is illustrated as being connected with a nestable tool assembly generally indicated at 281 which comprises a punch 276, a stripper sleeve 282, and a die 283. The punch-276 has a body portion 284 which has a punch end 285 and a threaded socket 286 engaging a threaded projection 287 of an attachment portion 275. The body portion 284 has an upper surface 288 which is in contact with the end surface 272 of the inner body portion 252, and a cylindrical outer surface 289 which has a radially extending locating pin 291 which extends through a slot 292 in the stripper sleeve 282 and into the slot 246 of the guide portion 233 to prevent relative rotation between the stripper sleeve, punch and guide portion. Y

The stripper sleeve 282 has an inner surface 293 slidably engaging the outer surface 289 of the body portion 284. At one end the stripper sleeve has an integral stripper plate 294 having an aperture 295 complementary to the punch end 285. At an end 296 opposite the stripper platei294, the stripper sleeve 282 has a snap ring retainer 297 partially disposed in a groove in the inner wall surface 293. v

The attachment portion 275 has a head portion 298 which is defined by a groove or neck portion 299. The head portion 298 is provided with an upper peripheral cam surface 301.

As illustrated in FIG. 12, the die 283 has a workpiece engaging surface 302 to support a workpiece 303. The workpiece engaging surface 302 has a die aperture 304 which is complementary to the cutting edges of the punch. The die 283 also has a depression 305 to receive the ball detent 248 to hold the die member in the station 247 of the lower turret 232. The die member 283 may be provided with an angular locating pin to be received in a groove in the lowerlstation 247 to prevent relative rotation, therebetween.

In operation the punch holder and drive assembly 14d is reciprocated in the guide portion 233 by the punch ram 259. After a workpiece 303 has been placed on the surface 302, the ram 259 begins its downward movement or punching stroke to force the punch 276 into contact and through the workpiece 303. The punching force of the ram 259 is transferred via the inner body portion 252 to the upper surface 288 of the punch member 276. During the punching stroke, the stripper sleeve 282 moves with the punch member 276 until the sleeve contacts the workpiece as illustrated in FIG. 12. Further downward movement of the stripper sleeve 282 is prevented by the workpiece 303 and a resisting force is transmitted by the upper surface 296 through the end surface 278 to the outer sleeve 255. With the arresting of the movement of the stripper sleeve 282 and the outer sleeve 255, the

pins

263, 263 move in the bores 261 with their heads'264 forcing the pistons 267 upwardly against the pressure exerted by the springs 269. It should be noted that the springs 269 insure that a stripping force is placed upon the workpiece 303 by the stripper sleeve 282. Upon completion of the punching of of the ram 259 and the beginning of the return stroke, the punch 276 is withdrawn from the workpiece and the stripper sleeve 282 is maintained in engagement or in a down position by the force applied by the springs 269 to the pistons 268 untilthe retainer 297 of the stripper sleeve 282 is engaged on the upper surface 288 of the punch 276. When the retainer becomes engaged by the punch 276 the stripper sleeve 282 is carried with the punch against the force of the springs 269 back into the guide portion 233 of the upper turret 231. 4

To unload the tooling from the punch holder and drive assembly 14d, the upper and

lower turrets

231 and 232 are rotated to an unloading/loading station which has a ram similar in structure to the ram 259 with the exception that an ejection pin is provided therein. The ram of the unloading/loading station moves downwardly causing the punch holder and drive assembly to move down towards the die 283 and to displace it, the movement continuing until the flange 265 of the sleeve 255 contacts the cushion 242. After the flange 265 of the sleeve 255 abuts the cushion 242, the ram of the unloading/loading station continues to move downward until the passageway 61d is in alignment with the passageway 279. At this time the gripping members 62d may be moved radially outwardly against the plugs 280 of resilient material from their normal locking position to an unlocked position. Once the passageway 61d is aligned with the passageway 279,

the ejection pin is moved into contact with the head 298 of the To load a tool assembly into the

stations

247 and 243, the

tool assembly is lifted through the station 247 of the lower turret 232 with the attachment portion 275 entering the counterbore 274. Continuation of lifting of the punch 276 causes the head portion 298 of the attachment portion 275 to contact the gripping members 62d and cam themoutwardly against the plugs 280 disposed in the passageways 279. Once the head portion 298 is past the gripping members, the resilient material of the plugs 280 forces the gripping members into engagement with the neck portion 299 of the attachment portion.- At this time, the gripping members are resiliently held by the resilient material in the normal locking position; however, the gripping members 62d can be easily moved to the unlocking position. Once the gripping members 62d are in the normal locking position, the loading/unloading ram begins to lift the punch holder and drive assembly upwardly with the inner body portion 252 moving with respect to the sleeve 255 so that the inner surface 254 closes the opening of the passageway 61d to positively maintain the gripping'members 62d in the normal locking position. Upon completion of the upward stroke, the punch holder and drive assembly 14d will assume a position similar to that illustrated in FIG. 11.

FIG. 13 shows a modified detent generally indicated at 1410 used with a head portion 45e which hasa T-shaped groove 137e. The detent 141a comprises a dog 310 having a rounded end 311 which is illustrated as being substantially hemispherical in shape and a curved surface 312 at the opposite end. The

dog 310 is pivotally mounted by a pin 313 in a slot 314 in the head portion 45e. The pin 313 passes through a bore 315 in the dog which is off center with respect to the

ends

311, 312, so that the end 311 tends to tilt to the position shown in the bold lines. The detent 141a includes a leaf spring 316 connected to the dog by a fastening means 317. The spring 316 has an end 318 which contacts a surface 319 of the groove 314 to load the spring as the dog is moved to the position illus trated in the dotted lines.

When the ram such as 138 moves into engagement with the T-shaped slot 1372 of the head portion 45c, it contacts the rounded end 311 and rotates or pivots the dog 310 about the pin 313 to a nonsupporting position shown in the dotted lines. In the nonsupporting position the curved surface 312 has been rotated or pivoted out of engagement with an upwardly directed edge 136a of the guide surface 130 of the sleeve 135 of the upper turret 131. When the turret 131 is rotated to disconnect the ram from the T-shaped slot 137e the force of the spring 313 plus the weight of the dog adjacent the end 31 1 causes the dog to pivot or rotate to the supporting position illustrated in the bold lines in which the curved surface 312 engages the upwardly directed edge 136a of the guide surface 130 to prevent the punch holder and drive assembly 14e from dropping downwardly in the station or guide surface 130 while disconnected from a ram. Although various minor modifications might be suggested by those versed in the art, it should be understood that we wish to employ within the scope of the patent warranted hereon, all such embodiments as reasonably and properly come within the scope of our contribution to the art.

We claim:

. 1. A punch holder and drive assembly for being reciprocated in a fixed guide portion of a punch press, said assembly comprising:

a. body means having an outer surface for being slidably guided during reciprocation by the guide portion of the punch press, a socket at one end of said body means opening in the direction of reciprocation, said socket having a locating surface receptive of a grooved portion of the punch, and a passageway in said body means extending transversely to the direction of reciprocation and intersecting said socket;

a gripping member disposed in .said passageway and movable between a normal locking position in which said gripping member extends into said socket for engaging the punch, and a retracted unlocked position in which said gripping member is retracted from any punch in said socket, said gripping member having a surface engageable in the grooved portion of the punch, said gripping member being movable out of said locking position in direct response to relative movement between the punch and said body means during both insertion and removal of the punch from said assembly; and

c. lock means carried by said body means and surrounding the axis of said socket for maintaining said gripping member in said locking position and for selectively enabling said gripping member to be moved to said unlocked position.

2. A punch holder and drive assembly according to claim 1, said passageway extending transversely to the direction of reciprocation and extending to said outer surface; said lock means including a pin slidably disposed in said passageway for acting between said gripping member and the fixed guide portion of the punch press.

3. A punch holder and drive assembly according to claim 2, wherein said pin has a ball-follower disposed for contact with the guide portion of the punch press.

4. A punch holder and drive assembly according to claim 2, wherein said pin has within it a spring biasing said gripping member toward said engagement position.

5. A punch holder and drive assemblyaccording to claim 2, wherein the outer end of said pin is receivable in a depression in the guide portion of the punch press to thereby effect the unlocking of said gripping member.

6. A punch holder and drive assembly for being reciprocated in a punch press, said assembly comprising:

a. body means for being slidably guided during reciprocation by the punch press, a socket at 'one end of said body means opening in the direction of reciprocation, said socket having a locating surface receptive of a grooved portion of the punch, and a passageway in said body means extending transversely to the direction of reciprocation and intersecting said socket;

b. a gripping member disposed in said passageway and movable between a normal locking position in which said gripping member extends into said socket for engaging the punch, and a retracted unlocked position in which said gripping member is retracted from any punch in said socket, said gripping member having a surface engageable in the grooved portion of the punch, said gripping member being movable out of said locking position in direct response to relative movement between the punch and said body means during both insertion and removal of the punch from said assembly;

0. a lock member carried by said body means for maintaining said gripping member in said locking position, said lock member having a head, a shoulder, a stem, and a cam surface on said head, said lock member being movable in said body means between a first position in which said cam surface urges and maintains said gripping member in said normal locking position and a second position in which said cam surface enables said gripping member to be moved out of said locking position; and

d. a stop means movable in said body means in a direction transverse to the direction in which said lock member is movable and engageable with said shoulder for maintaining said lock member in said first position.

7. A punch holder and drive assembly according to claim 6, wherein said lock means includes a spring biasing said lock member toward said second position. i

8. A punch holder and drive assembly according to claim 6, wherein said shoulder is formed by a groove on said stem.

9. A punch holder and drive assembly according to claim 6, wherein said shoulder is a surface of said head.

10. A punch holder and drive assembly according to claim 6, wherein said stop means includes a' pin slidably disposed in a second passageway in said body means extending transversely to the direction of movement of said lock member.

11. A punch holder and drive assembly according to claim 10, wherein said stop means further includes a spring biasing said pin toward engagement with said shoulder.

12. A punch holder and drive assembly according to claim 10, wherein said pin terminates at one end in a knob for enabling manual disengagement of the stop means from said shoulder.

13. A punch holder and drive assembly according to claim 10, wherein said pin has a second pin angularly extending through a slot in said body means and'being manually accessible to enable releasing of said stop means from engagement with said shoulder.

14. A punch holder and drive assemblyaccording to claim 10, in which said body means has an outer surface slidably engageable with a fixed guide portion of .the punch press, a second passageway extending from said lock member to said outer surface, said pin having a length for acting between said shoulder and the guide.

15. A punch holder and drive assembly according to claim 10, wherein said stop means includes a spring urging said pin out of engagement with said shoulder.

16. A punch holder and drive assembly according to claim 10, in which said body means has an outer surface slidably engageable with a fixed guide portion of the punch press, the

outer end of said pin being receivable in a depression in the guide portion of the punch press to effect the disengagement of said stop means from said shoulder.

17. A punch holder and drive assembly according to claim 10, wherein said pin has a cam surface at each end to effect movement of said pin to move said lockmember to said first position.

18. A punch holder and drive assembly according to claim 1, comprising:

a. a body portion forming part of said body means and having a second outer surface, having said passageway, and

having said socket; and

b. a sleeve comprising a part of said body means, said sleeve having an inner surface serving as said lock means and slidably received on said second outer surface of said body portion.

19. A punch holder and drive assembly according to claim 18, wherein said passageway extends outwardly to said second outer surface of said body portion.

20. A punch holder and drive assembly according to claim 19, wherein said gripping member surface is a ball slidably disposed in said passageway for acting between said inner surface of said sleeve and said punch.

21. A punch holder and drive assembly according to claim 20, wherein said inner surface of said'sleeve has means for receiving said ball to enable said ball to move to said unlocked position. j

22. A punch holder and drive assembly according to claim 21, wherein said receiving means includes resilient material to urge said ball toward said normal locking position.

23. A punch holder and drive assembly according to claim 18, wherein a portion of said inner surface is a resilient plug receptive of a portion of said gripping member.

24. A punch holder and drive assembly according to claim 1, wherein said body means include a head portion to form a detachable connection with a ram of the press, and a detent on said body means for coacting with an upwardly directed surface of the press at the guide portion to support said assembly while it is disconnected from the ram. 2 r

25. A punch holder and drive assembly according to claim 24, wherein said detent comprises a dog pivotally mounted adjacent to said head portion and movablebetween supporting and nonsupporting positions, means normally acting to move said dog into said supporting position, said dog having a portion engageable by the ram of the press to pivot said dog to the nonsupporting position as the ram is connected to said assembly.

26. A punch holder and drive assembly according to claim 6, in which said lock member is substantially concentric with said socket. g

27. A punch holder and drive assembly according to claim 6, in which said cam surface is disposed internally of said head and encircles an end of said socket.

28. A punch holder and drive assembly according to claim 1, including a plurality of said gripping members disposed about said socket. f

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,548,700 nated December 22, 1970 Inventor-(s) John H. Herzog and Ronald Hill It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 4, l. 48, delete "an" (first occurrence);

Col. 5, l. 53, delete "50";

Col. 7, l. 67, change "hold" to --held--;

C01. 8, l. 13, delete "50'';

C01. 8, l. 16, delete "a";

C01. 8, l. 21, change "4013b" to --40b--;

Col. 9, l. 60, delete "139" and insert --station--;

Col. 9, l. 74, change "143a" to --134a--;

Col. 14, l. 54, delete "of" (either occurrence); and

Col.17, 29, after "guide" insert --portion of the punc press-m.

Signed and sealed this 26th day of October 1971 (SEAL) fittuut:

EDWARD M.FLETOHER,JR. ROBERT GOTISGHALK Attesting Officer Acting Commissioner of Patents FORM PO-IOSO (IO-69)