Shut height adjustment means in pressing apparatus

A device for adjusting the shut height of a press includes a rotatable dial (16) interposed between a ram mounting block (6) fixed to a press ram (2), and a tooling ram (14). The dial (16) is keyed to a screw bushing (12) which is rotatable in a screw threaded bore in the block (6) for vertical movement relative to the block (6). Facing surfaces (46 and 48) of the block (6) and the dial (16) are formed with opposed helical ramps (54 and 56, and 58 and 60). The angular position of the dial (16) is adjustable to cause the ramps (54 and 56, and 58 and 60) to cooperate to alter the distance between ramps (2) and 14) to adjust the shut height of the press.

This invention relates to shut height adjustment means for determining the 
spacing between first and second rams in pressing apparatus, and relates 
especially to such means in presses for crimping electrical terminals to 
wires. 
Such crimping presses usually comprise a tooling ram carrying a crimping 
die for cooperation with an anvil to crimp a ferrule of an electrical 
terminal to a wire, the tooling ram being driven by a press ram through a 
working stroke to crimp the terminal to the wire and through a return 
stroke. In a crimping operation, the shut height of the tooling, that is 
to say the distance between the crimping die and the anvil at the end of 
said working stroke must be precisely adjusted if a satisfactory cold 
forged connection is to be made between the ferrule and the wire. This is 
disclosed in U.S. Pat. No. 3,115,922 and U.S. Pat. No. 3,184,950, which 
are incorporated herein by reference, a shut height adjusting means 
comprising a dial having a plurality of projections of varying heights 
thereon which is interposed between the two rams of a crimping press, and 
which can be rotated to determine the distance between the two rams and 
thus the shut, or crimp, height of the tooling. However, the shut height 
can only be adjusted stepwise, by interposing selected projections between 
the rams. 
The present invention is intended to provide for the continuous adjustment 
of said shut so that it can be finely adjusted for use with any terminal 
within a given size range, rather than only with terminals of selected 
sizes within that range. 
According to the invention, in pressing apparatus having a first ram and a 
second ram connected thereto in spaced relationship therewith to drive the 
first ram along a predetermined path, adjusting means for altering the 
spacing between said rams, comprises a ram mounting block fixed to the 
second ram and being located between said rams, said block having a screw 
threaded bore having a longitudinal axis extending lengthwise of said 
path; a screw device in said bore meshing with the threads thereof and 
being rotatable therein about said axis, for movement relative to said 
block, lengthwise of said axis, said screw device being connected to said 
rams with axial play; a dial keyed to said screw device, for rotation 
about said axis to move the first and second rams relatively towards and 
away from each other; and ramp means acting between said block and said 
dial, for determining the spacing between said rams in accordance with the 
angular position of said dial about said axis, the second ram being in 
force transmitting relationship with the first ram by way of said block 
and said dial as said first ram is driven by said second ram. 
The ramp means may comprise a pair of helical ramps on each of the blocks 
and the dial, the ramps extending about said axis and the helical pitch of 
each ramp being the same as that of the screw threads of the block and the 
screw device, the ramps being of equal angular extent and being arranged 
in opposed relationship. The screw device preferably comprises an 
externally screw threaded bushing which is rotatable about a hub, 
connected to the rams with clearance. 
The dial may be marked with a scale but is preferably surrounded by a scale 
bearing sleeve which is angularly adjustable about said axis. 
The shut height adjusting means may be incorporated between a press ram of 
a power driven press and a terminal applicator which is detachably mounted 
to the press, or the shut height adjusting means may be incorporated in 
the applicator itself. 
Said angular position of the dial may be set manually and the scale bearing 
sleeve adjusted angularly to account for press or tooling drift (settling 
in) which may occur during continuous operation. 
Should the press be included in a fully automatic lead making, or harness 
making, machine, the dial may be angularly adjusted under the control of 
an electronic control circuit of the machine.

As shown in FIGS. 1 and 2, a press ram 2, which is arranged to be driven in 
vertical reciprocating motion, through working and return strokes, by 
means of a driving mechanism (not shown), for example, according to U.S. 
Pat. No. 3,184,950, has fixed thereto, by means of bolts 4, a circular 
cross section, press ram mounting block 6 formed with an internal, screw 
threaded, axial bore 7 having screw thread 8. The thread 8 meshes with 
external screw threads 10 of a screw threaded bushing 12 which is 
rotatable in the bore 7 about the vertical axis Z--Z of a central hub 13 
in the bushing 12, for adjustment lengthwise of the vertical path of 
movement of the ram 2. The lower end of hub 13 is connected with play to a 
tooling ram 14 driven by the ram 2 and carrying tooling (not shown) which 
may be an electrical terminal crimping die for cooperation with an anvil 
(not shown), according to the teaching for example of U.S. Pat. No. 
3,184,950. 
There is interposed between the block 6 and the ram 14, a shut height 
adjusting annular dial 16 having a keying nose 18 projecting radially 
inwardly of the dial 16 and which slidably engages in a vertical keying 
slot 20 in the bushing 12. At its lower end, as seen in FIGS. 1 and 2, the 
hub 13 has an annular flange 22 which is received in an undercut blind 
bore 24 in the ram 14, the lower face 26 of the flange 22 being spaced 
from the base 28 of the bore 24 with clearance G2. The upper face 30 of 
the flange 22 engages the upper face 32 of the undercut in the bore 24. 
The upper end of the hub 13 is surrounded by a bearing ring 34 secured to 
the hub 13 by means of a pin 36 extending through aligned transverse bores 
33 and 35, respectively, in the hub 13 and the ring 34. The ring 34 is 
slidably received in a circular cross-section bore 37 in the ram 2. 
The dial 16 is surrounded by a scale sleeve 38 marked with a scale 40 
extending thereabout. The sleeve 38 is secured to the dial 16 by means of 
a screw 42 (FIG. 3) passed through a peripherally extending slot 44 in the 
sleeve 38 and into a tapped opening 45 in the dial 16, so that the angular 
position of the sleeve 38 is adjustable about the axis Z--Z with respect 
to the dial 16. 
The adjacent faces 46 and 48, respectively, of the block 6 and of the dial 
16, are formed with cooperating adjustment ramp means generally referenced 
50 and 52, respectively. The ramp means 50 comprises a pair of helical 
semicircular ramps 54 and 56, and the ramp means 52 comprising a pair of 
helical semicircular ramps 58 and 60. The ramps of each pair extend about 
the axis Z--Z in opposed relationship, Each ramp of each pair being in 
rotational symmetry in respect to the other ramp of the pair and the 
helical pitch of each ramp, being the same as that of the screw threads 8 
and 10. 
The ramp means 50 and 52 cooperate with one another in such a way that as 
the dial 38 is rotated, in relation to a bench mark (not shown) on the 
block 6 or the ram 14, the bushing 12 and thus the hub 13 are moved, 
relative to the ram 2, along the axis Z--Z, between the positions in which 
the bushing 12 and the hub 13 are shown in FIGS. 1 and 2, thereby to 
determine the spacing between the rams 2 and 14 and thus the shut height 
of the tooling, in accordance with the angular position of the dial 16 
about the axis Z--Z. 
As the dial 16 is turned in a clockwise (as seen in FIGS. 1 and 2) sense, 
from the position of FIG. 1 (maximum shut height) to that of FIG. 2 
(minimum shut height), the effective combined height of the block 6 and 
the dial 16 is increased, so that the distance between the rams 2 and 14 
is also increased. However, the minimum clearance G1 between the block 6 
and the dial 16, which may be of 0.004 inches, remains the same in all 
angular positions of the dial 16. The clearance G2 between the faces 26 
and 28, which may be of 0.006 inches and which in any event must always 
exceed the clearance G1, also remains the same in all angular positions of 
the dial 16. The difference between the maximum clearance G3 between the 
block 6 and the dial 16 in the FIG. 1 position of the bushing 12 and hub 
13, and the maximum clearance G4 between the block 6 and the dial 16 in 
the FIG. 2 position of the bushing 12 and hub 13, is commensurate with the 
extent to which the said shut height can be adjusted by means of the dial 
16. 
As the ram 2 is driven through its working stroke, the clearance G1 is 
eliminated, but since the height of the clearance G2 always exceeds that 
of the clearance G1, the ram 2 is in force transmitting relationship with 
the ram 14 by way of the block 6 and the dial 16. 
The clearance G1 could, for example, be of between 0.002 and 0.006 inches, 
but is constant as mentioned above, and must in any event be smaller than 
the clearance G2.