Apparatus for assembling and banding an expansion shell

An automatic machine for assembling and banding together the components making up an expansion shell so that the assembly can be conveniently packaged and shipped. In one embodiment, the machine contains a series of work stations arranged to assemble the bolt components within a die. The expansion shell halves are staked to a common strap and the components then passed through a combination forming gage and banding mechanism which aligns the parts in assembly and bands them together using a plastic sleeve. In a second embodiment of the invention, the expansion shells are staked to the strap prior to being loaded into the die.

BACKGROUND OF THE INVENTION 
This invention relates to apparatus for automatically assembling and 
banding together the component parts of an expansion shell to prevent the 
parts from becoming separated prior to usage. 
Many types of widely used expansion or mine bolts are formed by staking two 
shell halves to a common strap and positioning the shell halves 
symmetrically about a tapered expansion wedge. A resilient sleeve is 
passed over the assembly which serves to hold the shell components in 
alignment so that the assembly will not become separated prior to actual 
usage. 
Heretofore, the assembling and banding together of the shell components has 
involved a relatively large number of hand operations that are generally 
time consuming and costly. 
To reduce the number of hand operations involved, devices have been devised 
for carrying out some of the assembling steps automatically. One such 
device is disclosed by Prince U.S. Pat. No. 3,842,476 wherein the shell 
halves are staked to the strap and the strap then bent about the wedge to 
provide an assembled but unbanded unit. The staking operation is carried 
out by bringing a coining tool down normal to a pair of raised ears 
carried by the shell halves with a high enough force to cause the ears to 
be deformed into locking contact against the strap. Because the tool acts 
normal to the work, high stresses are generated resulting in premature 
breaks and relatively tool life. 
Regardless of how they are assembled, most expansion shells are subjected 
to a minimal amount of inspection. For the most part the inspection is 
carried out visually on a few samples selected from a large batch. The 
defect which is most troublesome generally involves an outwardly extended 
section which causes the shell to hang up in the receiving hole so that 
the shell spins in the hole rather than expanding outwardly. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to improve apparatus for 
automatically assembling expansion shells as typically used in mine bolts. 
A further object of the present invention is to extend the tool life of a 
punch used to stake the shell halves of an expansion shell to a common 
strap. 
Another object of the present invention is to automatically inspect mine 
bolt shells as they are being assembled. 
A still further object of the present invention is to provide a machine for 
automatically bringing together the component parts of an expansion shell 
and banding the parts together into an assembly. 
Yet another object of the present invention is to reduce the amount of hand 
labor required to assemble and band together the components of an 
expansion shell. 
These and other objects of the present invention are attained by means of 
an automatic machine for loading the component parts of an automatic 
machine for loading the component parts of an expansion shell into a die, 
staking the shell halves to a strap and passing the components in 
alignment through a forming block and band applying mechanism whereby the 
strap is deformed about the wedge to true the halves in relation with the 
wedge and a sleeve is passed over the assembly to hold the parts thereof 
in their respective assembled positions. 
In a second embodiment of the invention the shell halves are staked to the 
strap prior to being mounted on the die thereby reducing the number of 
work stations.

DESCRIPTION OF THE INVENTION 
As illustrating in FIG. 1, the present invention is embodied in an 
automatic machine, generally referenced 10, for assemblying and banding 
together the component parts of an expansion shell of the type typically 
used in mine bolts for supporting the roof of a mine shaft. The machine 
includes a circular indexing table 11 rotatably supported in the machine 
frame and arranged to transport six die members 12 through a like number 
of work stations. The machine further includes a hydraulic ram and 
cylinder 15 and a motor and pump unit 16 the function of which will be 
explained in greater detail below. A pair of control panels 17 and 18 
house the electrical and hydraulic components for operating and 
controlling the various machine processes. In operation, the component 
parts making up the shell assemblies are stored about the machine in a 
series of vibratory bowls that are adapted to dispense the parts into the 
various work stations. One of the bowls 20 is depicted in FIG. 1 and 
contains a plurality of resilient sleeves for banding the shell assemblies 
together. 
Referring now to FIG. 4, there is shown a shell assembly 21 of the type 
processed in the present apparatus. The assembly consists of a centrally 
located wedging nut 22 having a tapered body and two symmetrical expansion 
shell halves 26--26 joined together by a metal strap 24. The strap is 
joined at each end to the shell halves by means of a coining operation 
whereby the metal of the shell is staked against the strap at points 
26--26. As is well known in the art, the mid-section of the strap is 
provided with a curved portion that is received within the threaded hole 
of the wedging nut and serves to center the shell and strap subassembly 
about the wedge. In operation, the shell components are formed into the 
assembly as shown and a resilient sleeve 25, generally made of plastic, is 
passed over the assembly to hold the parts in alignment whereby the shell 
can be conveniently handled and packaged prior to being joined to a bolt 
at the mine site. 
Turning now to FIG. 2, there is illustrated six work stations A-F located 
about the periphery of the indexing table 11. A die member 12 is 
positioned in each work station with the dies being circumferentially 
spaced about the table at 60.degree. intervals. Through means of the 
machine control system the table can be indexed automatically or manually 
to periodically reposition each die member into the next subsequent work 
station. In operation, the table is turned in a clockwise direction 
whereby the dies are transported in an ordered sequence through each of 
the six work stations. 
One of the six identical die members is shown in further detail in FIG. 3. 
The die includes a horizontal base plate 29, which is secured to the 
indexing table, and an anvil section 30 having a truncated pyramid 
configuration. The two inclined surfaces 31--31 of the pyramid shaped 
anvil function as shell support platforms and each contains a raised cone 
shaped saddle 32--32 thereon. Each saddle is adapted to compliment the 
inner surface of a shell whereby the shells can be securely seated upon 
the respective platforms. With further reference to FIG. 7, a foot rest 
33, having a raised wall normal to the platform, is provided at the bottom 
of platform and provides a support and locating surface against which the 
bottom surface of a shell seated upon the saddle rests. Each of the 
inclined platforms is enclosed by a pair of raised side walls 34-34 and a 
raised end wall 35 to establish a nest into which the shells are 
automatically delivered. 
A vertical hole 37 is centrally located in the anvil. The hole extends 
downwardly from the top surface 38 of the anvil and passes through both 
the anvil body and the underlying indexing table. The upper section of the 
hole is tapered to compliment the body of the wedging nut 22. As will be 
explained below, a wedge is inserted into the hole and caused to become 
automatically seated against the tapered opening so as to align itself 
within the die. 
Strap guides 39 and 40 are secured to the side walls of the anvil via cap 
screws 41 to hold the guides in vertical alignment on either side of the 
top opening of hole 37. A vertical slot 42 is formed in each guide and 
adapted to receive a strap therein. In assembly, the grooves are aligned 
with the central axis of each cone shaped saddle and the center of opening 
37. The raised guides coact with the top surface of the anvil to form a 
nest into which wedges are loaded. 
As will be explained in greater detail below, the various components making 
up the expansion shell assembly are automatically loaded into each of the 
dies as they pass sequentially through the work stations. After loading, 
the hydraulic ram brings a punch down against the shells to stake the 
strap in place. Lastly, the components aligned on the die are passed 
upwardly through a forming block to shape the assembly and a plastic 
sleeve is passed over the assembly to prevent the assembly from separating 
during handling. 
Initially, a wedge 22 is automatically loaded into the wedge nest of the 
die at work station A which has been cleared of shell components of work 
station F. With reference to FIGS. 5 and 6, individual wedges are 
delivered from a vibratory bowl onto an inclined slide 45 having a blunt 
edged blade 46 formed upon its upper surface. Under the influence of the 
vibratory bowl, the bifucated wedges straddle the blade and are fed one at 
a time down the blade as illustrated into the work station. 
A gating mechanism 50 is located at the wedge entrance to the work station. 
The mechanism includes an air operated escapment 51 that is automatically 
activated from the machine control network. The escapment is mounted upon 
a bracket 55 adjacent to the slide and contains a pair of gates 52 and 53 
which are adapted to move in and out of arresting contact with the parade 
of wedges moving down the slide. Through the escapment mechanism, the 
direction of motion of the gates is staggered so that one gate will be 
inserted into the wedge path of travel while the other is retracted. 
Initially, the first wedge in the series is arrested against extended gate 
52 prepatory to being moved down the slide onto a balancing mechanism 54. 
Upon receipt of a timed signal, indicating the balance is clear, gate 52 
is retracted to release the first wedge while, simultaneously therewith, 
the second gate 53 is inserted into arresting contact with the second 
wedge in the series. Once the first wedge has cleared the gating station 
the position of the gates is reversed thus resetting the mechanism for a 
new cycle. 
Upon clearing the gates, the wedge moves down the slide onto the 
horizontally extended arm 57 of the balance. The balance is pivotably 
supported in vertical wall 58 upon pin 59. A weight 60, secured to the 
vertical arm of the balance, is arranged to offset the weight of the 
weight whereby the wedge is suspended directly over the wedge nest of the 
die positioned in station A. Upon the delivery of an empty die into the 
station, air cylinder 62, positioned above the balance, is actuated 
causing arm 63 to be extended downwardly. A wedge actuator 64, affixed to 
the arm, contacts the wedge positioned upon the balance and drives it down 
into the tapered end of the die opening 37. A limit switch 65 is arranged 
to sense the action of the air cylinder and, among other things, prevents 
the table from being indexed prematurely and actuates escapement 51. 
With a wedge loaded into the die, the table is indexed so that the die is 
moved into work station B where a pair of shell halves are loaded into the 
two shell nests 36--36. Referring now more specifically to FIGS. 7-9, the 
shells are delivered into the nests from a pair of magazines 67,68 
suspended above the work station from a common bracket 69. The magazines 
are of similar construction and operate in the same manner to carry out 
the loading operation. 
Each magazine is generally U-shaped in cross-sectional form including an 
inclined channel 70 and a shell injector 71 mounted on the lower end 
thereof. Here again, each injector employs an air operated escapment 73, 
which is secured to one of the sidewalls of channel 70, to control the 
shell loading operation. The escapment is adapted, upon the receipt of a 
timed signal, to raise and lower gates 74 and 75. As shown in FIG. 7, the 
forward gate 74 is shown lowered while the rear gate 75 is raised. 
As is the case of the wedge escapment, the first shell in the stack is 
resting against forward gate 74 and a head rest 76 when the die moves into 
the station. With the die properly indexed, the forward gate is lowered to 
release the foot end of the shell and, simultaneously therewith, the rear 
gate is raised to hold back the remaining shells in the magazine. Upon 
releasing the foot end of the shell, the shell is caused to swing 
downwardly about head rest 76 into the shell nest. By proper positioning 
of the magazines in regard to the die, the released shells will slide 
downwardly onto the saddles and align themselves against footrest 32. 
After releasing the first shell in the stack from the magazine, the 
position of the two gates is once again reversed thereby readying the 
station for the next cycle. To insure that the shells loaded into the 
magazines will move down the channel in proper alignment, a biasing means 
is provided which functions to continually urge the shells downwardly into 
the gates. 
With the shells and the wedge loaded into the die, the table is again 
indexed to move the die into work station C. Here a preformed strap 24 is 
accurately positioned in relation to both the shell halves and the wedge 
as best seen in FIGS. 10-12. As is well known in the art, the straps are 
preformed into a M-shaped configuration with the curved midsection thereof 
arranged to be received in the threaded hole of the wedge. The two ends of 
the strap are crimped so that they may be snapped between the raised ears 
86 depending upwardly from the face of the shells. 
Here again the straps are stored in a vibratory bowl similar to bowl 20 
(FIG. 1) and moved down an inverted channel 79 into the work station. A 
round bar 80 is supported by means of a frame 78 in the channel opening 
thus forcing the straps to be aligned as shown in FIG. 12 upon the 
channel. A vibratory motion is imparted to the channel causing the straps 
to move down against vertical wall 81 of strap injecting mechanism 82. The 
first strap in the channel alignment is permitted to rest upon the 
horizontal arm of a balance 78 similar to that described above. 
A spring-like member 83 is secured to the bottom of the channel and is 
turned downwardly whereby its lower leg is brought into parallel alignment 
with wall 81 to form a guideway 77. The normal gap between the back wall 
and the biased forward wall is slightly less than the width of the straps. 
In operation, the strap seated upon the balance is driven downwardly by 
means of plunger 85 attached to the arm of air cylinder 86. The lower end 
of the plunger is contoured to compliment the strap profile and thus 
support the strap in alignment as it is being moved into the die. 
Upon moving down from the balance, the strap is forced into the guideway 77 
against the biasing force of spring 83 whereby the strap maintains its 
desired alignment until it is released to the guides 39,40. Under the 
influence of the plunger, the strap is seated within the slots 42 formed 
in the guides and the ends thereof snapped into position between the 
raised ears of the shells. 
Next, the table is indexed to bring the loaded die into an inspection 
station D where the positioning of the shell parts can be inspected. The 
inspection may be carried out visually by the operator or automatically by 
means of optical sensors, capable of shutting the machine down in the 
event one of the parts is misaligned. 
Further indexing of the table brings the die into the staking station E 
wherein the ears 86 on the shells are coined into holding contact against 
the strap. With further reference to FIGS. 13-15, the die is indexed in 
station E directly below a staking tool containing a pair of punches 
88--88 that are securely supported within a shoe 89 via bolts 90. Although 
not shown, the spindle 91 of the tool is operatively attached to the ram 
of the hydraulic cylinder 15 shown in FIG. 1. The working surface 92 of 
each punch is arcuate shaped and is offset from the horizontal plane at 
about the same angle as are the two platforms 31--31 of the anvil. As 
depicted by the phantom outline in FIG. 13, the punches are brought down 
into coining contact with the ears 86 of the two shell halves seated in 
the shell nests. Sufficient force is applied to deform the ears against 
the strap thus staking the two shells to the strap. As can be seen, the 
punches are designed to move against the ears with a sliding motion rather 
than coming down with a direct compressive force normal to the ears. As a 
result of the sliding action, the ears are coined incrimentally as the 
tool advances therealong thus requiring less energy and causing the tool 
life to be considerably extended. This sliding action has been found also 
to create an extremely strong mechanical bond between the strap and the 
shells. 
After staking or coining the straps to the shells, the die is further 
indexed into the forming and banding station F wherein the shell 
components are shaped into a final assembly and banded together by means 
of a thin plastic sleeve 25. Special equipment is herein provided to 
automatically deliver the thin sleeves to the work station. As depicted in 
FIGS. 18-19, the sleeves are stored in a vibratory bowl 20 and are moved 
therefrom in series alignment into a vertical feed tube 93 via a 
substantially enclosed ramp 94 that is secured to the side of the bowl by 
bracket 95. 
As best seen in FIG. 19, the floor 96 of the ramp extends outwardly in a 
horizontal direction from the main body of the ramp and is suspended over 
the top entrance of the feed tube. A circular slot is formed in the 
extended end of the floor to permit individual bands walking down the ramp 
to fall into the feed tube. The cross-sectional geometry of both the 
enclosed ramp 94 and the feed tube 93 are such that the sleeves will be 
continually supported in a vertical position as shown. 
An enlarged cylinder 97 is threaded onto the cap at the entrance to the 
feed tube as illustrated in FIG. 19. A loading member 98 is pressed into 
the cylinder and is arranged to enclose the extended platform 96 of the 
ramp. A polished free floating ring 99 is also housed within the cylinder 
between the top of the feed tube and the bottom of the loading member. In 
assembly, the upper section of the feed tube is secured by any suitable 
means to the ramp so that the two cojoined elements are both agitated by 
the vibratory bowl. In operation, the ring 99 is caused to reciprocate 
vertically within the cylinder and thus direct the sleeves in transit 
downwardly into the feed tube. 
Turning now more specifically to FIGS. 16-17, it is shown that the lower 
exit of the feed tube 93 discharges into a slide mechanism 104 for 
dispensing the sleeves one by one into the work station F. Upon entering 
the feed tube the sleeves are directed downwardly onto a horizontal plate 
100 having upper side margin guides 101 and lower side margin guides 102 
associated therewith to create a lateral passageway for guiding the 
sleeves to a position over the die located in the work station. In 
operation the slide 104 is driven horizontally along plate 100 by means of 
an air cylinder 106 acting through arm 105 in response to a timed signal 
from the machine's control circuitry. The end face 109 of the slide, which 
engages the sleeve positioned on the plate at the exit to the feed tube is 
contoured to compliment the sleeve so that the slide will embrace the 
outer surface of the sleeve as it moves laterally into the work station. 
Full extension of the slide will position the sleeve against the contoured 
surface 108 of the holding block surface 107. A soft spring 110, secured 
to the bottom of the block 107, is extended vertically along surface 108 
and serves to put a slight biasing pressure against a sleeve advanced by 
the slide into the work station. As illustrated by the phantom outline in 
FIG. 16, the spring combines with surfaces 109 on the slide and 108 on the 
block to force the sleeve into a cylindrical posture over the die 12. 
Positioned immediately below the holding block 107 is a second gage block 
103 having a circular hole 112 formed therein containing an expanded 
opening 113 facing the die 12. As shown, the centerline 115 of the gage 
block is coaxially aligned with the central opening 37 passing upwardly 
through the die and the indexing table. 
In practice, a sleeve is first brought into the holding block 107 and then 
a dejecting rod 117, located below the table, is driven upwardly through 
hole 37 into driving contact against the bottom of wedge 22 positioned in 
the die. The wedge is pushed upwardly against the curved midsection of the 
strap thus lifting the shells out of their respective nests. Continued 
extension of rod 117 forces the expansion shell components upwardly 
through the forming gage block wherein the strap is shaped to bring the 
shell halves in alignment with the wedge. As best seen in FIG. 17, the 
formed assembly is then passed into the resilient sleeve which is caused 
to embrace the components and hold them together in their assembled 
positions. 
With the rod 117 fully extended, the slide is pulled back allowing the 
shell assembly to be cleared from the station. The banded assembly 21 is 
pushed out of the work station by means of a kicker bar 120 pivotably 
supported above block 107 by pin 122. A biasing spring 121 acts against 
the bar to continually urge the bar in a clockwise direction. As a 
consequence, the shell assembly upwardly through the forming gage is 
brought into contact with the bar whereupon the assembly is pushed out of 
the station when the slide is retracted. Although not shown, means are 
provided to direct the assembled and banded shell into a collecting bin. 
It should be noted at this point that the forming gage also functions as an 
inspection tool which is capable of rejecting misaligned or oversized 
assemblies. The gage opening is sized so that any such defective 
assemblies will be prevented from passing therethrough whereby the 
assembly is rejected before it can be packaged and shipped to the mine 
site. As can be seen, each assembly produced by the machine of the present 
invention is thus individually and automatically inspected to insure its 
reliability when placed in operation. 
An optical detector 125 is positioned below the table within work station F 
to sense the positioning of the rod 117. The sensor is connected into the 
machine control circuitry so as to prevent the table from being indexed 
when the rod is in an extended position. 
Turning now to FIG. 20 and FIG. 21 there is illustrated a second embodiment 
of the invention wherein the number of work stations have been reduced to 
three. As shown in FIG. 20 the stations are positioned at 120.degree. 
intervals about the table 11. Stations A and F are as described above both 
in regard to the structure involved and the function thereof. Station G is 
similar to original station C in regard to its structure; however, as seen 
in FIG. 21, the shell halves in this embodiment are prestaked to the strap 
and the subassembly then delivered into the machine. The shell and strap 
subassemblies 127 are mounted upon a guide channel 79 and placed one by 
one onto the balance arm assembly 82, as seen in FIG. 10, directly over 
the die in station G. A contoured pusher arm 85, driven by an air 
cylinder, as noted above, forces the subassembly downwardly between 
stationary wall 81 and biasing bar 83 into the die in timed response with 
the other machine operations. 
While this invention has been described with reference to the details as 
set forth above, it is not limited to the specific structure as disclosed 
and the invention is intended to cover any modifications or changes as may 
come within the scope of the following claims.