Note: Descriptions are shown in the official language in which they were submitted.
V;~S
This invention relates to automatic tool changers
for machine tools.
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In the past, many diIferent types o~ automatic tool
changers have been built, including some tool changers which are
adapted to handle either single too:Ls or small multiple spindle
tool heads, but not large multiple spindle tool heads.
The principal object of this invention is to provide
an automatic tool changer which is capable of handling single
tools and/or relatively large multiple spindle tool heads, e.g.
tool heads that weigh as much as 1,000 pounds. Another obJect
of the inrention is to pro~ide a novel multiple spindle tool
head which can be handled by an automatic tool changer that is
adapted to handle single tools. Other ob~ects and advantages
of the invention will be apparent ~rom the detailed description
- herein.
- The present~invention provide~ an automa'lc tool changer
for transferring single tools and multiple spindle toolheads
between a tool storage magazine and a horizontal splndle of a
m~ch~ne tool, said tool changer comprising means in said tool
s'orage magazine ~or storing a plurality of single tools and
multiple spindle toolheads witll the shanks thereof in a vertical
position, chara^terized by a tLlt unit for holding a tool or tool-
head and tilting the shank o~ the held tool or tooIhead by 90 from ~-
~ vertical to a horizontal position-or from a horizontal to a
- ~- vertic 1 position, a first tool change arm mounted for movement
~: between said tool storage magazine and said tilt unit for trans-
ferring a tool or toolhead from said tool storage maeazine
to said tilt unit or from said tilt unlt to said tool storage
magazine and a second tool change arm mounted ~or movement
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between said tilt unit and said spindle for transferring said
selected tool or toolhead from said tilt unit to said spindle
and from said spindle to said tilt unit.
Each multiple spindle toolhead has support and clamp
means on its rear portion which coacts with support and clamp
means on the spindlehead of the machine tool to support the
toolhead and hold it stationary while the shank and tools of
the toolhead are rotating with the spindle.
Thus, in accordance with the invention, there is
provided a machine tool having an automatic tool changer for
changing the tools used to operate on a workpiece; a bed; a
column slidably supported by said bed for movement in a recti-
linear path of travel; a spindlehead carried by said column
for movement therewith along said rectilinear path of travel;
a spindle rotatably supported by said head and adapted to re-
ceive a rotary cutting tool for operating on a workpiece, the
improvement comprising: a frame slidably supported by said
bed and being attached to said column for movement with said
column in said rectilinear path of travel; a tool storage
magazine mounted on said frame and adapted to carry a plural-
ity of vertically positioned cutting tools for use in said
spindle; means associated with said magazine for selecting
the next tool to be used in said spindle; tool transfer means
mounted on said frame in position to transfer tools between
said tool storage magazine and said spindle, whereby said ::
magazine and said tool transfer means are carried by said
bed but move with said column by reason of their mounting on
said frame so that they always remain in proper position
relative to said spindle along said rectilinear path of
travel for completing a tool interchange operation, a tilt .
unit adapted to receive a tool; a tool gripper arm movably
supported by said frame for transferring a tool from said
magazine to said tilt unit in a vertical position and to re-
turn the tools from said tilt unit to said magazine; and
means connected to pivot said tilt unit between a vertical
position for receiving tools from said tool gripper arm and
a horizontal position for locating a tool in position to be
engaged by said tool transfer means for transfer to said
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spindle and to receive a previously used tool from said trans-
fer means for return to said magazine.
The invention is illustrated in particular and pre-
ferred embodiments by reference to the drawings in which:
Fig. 1 is a front elevational view of a horizontal
machining center which utiliY,es an automatic tool changer of
this invention,
Fig. 2 is a plan view of the machining center o~
Fig. 1,
Fig. 3 is a plan view of the tool storage magazine;
Fig. 4 is a fragmentary plan view of one end of the
tool storage mayazine;
Fig. 5 is a side elevational view taken on the line
5-5 of Fig. 3,
Fig~ 6 is a cross-sectional view taken on the line
6-6 of Fig. 3;
Fig. 7 is a cross-sectional view taken on the line
7-7 of Fig. 3;
Fig. 8 is a longitudinal sectional view taken on
the line 8-8 of Fig. 4,
Fig. 9 is a cross-sectional view of a tool socket
taken on the line 9-9 of Fig. 3;
Fig. 10 is a plan view of the tool change arm which
transfers tools and toolheads from the tool storage magazine
to the tilt unit and vice versa; `~
Fig. 11 is a radial sectional view taken on the
line 11-11 of Fig. 10,
Fig. 12 is a fragmentary longitudinal sectional
view taken on the line 12-12 of Fig. 11;
Fig. 13 is a cross-sectional view taken on the line
13-13 of Fig. 11,
Fig. 14 is a cross-sectional view taken o,n the line
14-14 of Fig. 11;
Fig. 15 is a front elevational view of the tool change
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arm o~ Fig. 10;
Fig. 16 is a rear elevational view o~ the upright
which supports the tool change arm of Fig. 10;
Fig. 17 is a side elevational view of the upright
which supports the tool change arm of Fig. 10;
Fig. lB ls a side e~evational view of the tilt unit;
Fig. ~9 is a plan view of khe tilt unit;
Fig. 20 is a ~ront elevational view ~f the tilt unit;
Fig. 21 is a fragmentary plan view, partially cut a-
10 -way,-of the tool chang~ arm which transfers tools and toDlheads
between the tilt unit ànd the spindle o~ the machining center;
Fig. 22 is a rear elevational ~iew taken on the line
22-22 of ~ig. 21;
Fig. 23 is a fragmentary plan view, partially cut a-
way, of the tool change housing ad~acent to the spindle of the
mach~ning center;
. Fig. 24 is a cross sectional view taken on the line
2~-24 of Fig. 21;
Fig. 25 is a front elevational view o~ the tool
change arm of Fig. 21 with the.front cover cut away and the arm
.in its vertical position;
. Fig. 26 is a ~ront elevational view of the tool
change arm of Fig. 21 with the ~r~nt cover cut away and the arm ..
in its horizontal position;
. Fig. 27 is an axial sectional view of the spindle;
F~g. 28 is a fragmentary plan view of the tool change
housing ad~acent to the spindle Or the machine tool;
Fig. 29 is a ~ragmentary ~ront eleYatlonal view taken
on the line 29-29 of Fig. 2~;
30Fig. 30 is a cross sectlonal view taken on the line
30-30 o~ Fig. 28;
Fig. 31 is a fragmentary longitudinal sectional view
.. taken on the line 31-31 of Fig~ 25; - .
-- F~g. 32 ls ~ ~ragmentary cross section~l view taken
on the line 32-32 of Fig. 31;
Flg. 33 is a long~tudinal sect1onal view ~f a mul~iple
spindle toolhead~ mo~nted in the machlne t~ol splndle,
Fig. 34 ls a longitudinal sectional vlew of the fiUp-
port and clamp means on the spindlehead ~or clamping a toolhead
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thereto and for suppvrting the toolhead;
Fig. 35 is a fragmentary front elevational-v~ew taken
on the line 35-35 o~ Fig. 34;
Fig. 36 is an end YieW of a threaded stud which pro-
~ects fr~m the rear ~f the multi~le spindle toolhead shown ln
Fig. 33;
Fig. 37 is a fragmentary plan ~iew taken on the line
37-37 of ~ig- 34;
Fig. 38 is an exploded perspective view of one o~
the s~uds which ~orm part of the c:Lamp and support means for
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the mul~iple spindle toolhead;
Fig. 39 ~s a side elevakl~nal view o~ a boring bar
adapted to be used in the machine tool and automati~ tool changer
of this invention; and
Fig. 40 is a block diagram of the electrical circuiks
which control the machine tool and automatic tool changer o~
this invention.
Figure 1 is a front elevational view and Fig. 2 is
a plan view of a horizontal machining center whlch is equipped
with an automatic tool changer o~ this invention. The machining
center includes a bed 50 upon which a saddle 52 is slidably
mounted ~n X-axis ways 54 (Fig. 2). Saddle 52 is dr~Yen along
ways 54 by a rack and pinion drive which consists of a rack 56
(Fig. 2) on bed 50 and two pinions 58 on saddle 52 which are
driven by a servo motor 60 through a conventional speed reduction
gear box 62. Motor 60 is selectively energized by a conventional
numerically controlled X-axis servo system (not sh~wn) to move
saddle 52 to any deslred position along the X-axis
A pair o~ flexible metallic cover sheets 53 are coupled
between opposite side edges of saddle 52 and a corresponding pair
of storage rollers 55 which are mounted on opposlte ends of bed 50.
CoYer sheets 53 are both made ~ relatively narrow interloc~ed
metal slats 57 (Fig. 2) and easily roll up on their respective
rollers 55. Both rollers 55 are torslon biased away ~rom saddle
52 by motors 59 (Fig. 1) and maintain a tension ln cover sheet~
53 at all times ~o that each cover sheet 53 will roll ~p auto-
matlcally when iaddle 52 moves toward ~t while the oppos~ng cover
sheet 53 will b~s drawn o~ its roller ~5 agalns~ the rorce o~ ~he
corresponding motor 59. Cover ~heets 53 protect the portions o~
X-axls ways ~4 th~t sre not oovered by saddle ~2.
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A set o~ Z-axis ways 64 are f~rmed on top of saddle
52 perpend1cular to X-axis ways 54. An upr~ght 66 is slidably
mounted ~n Z axLs ways 64 and is driven there along by a con-
vent~onal ballscrew drive (not shown) whlch ~s powered by a
servo'm~t~r 68 (Fig. 2). Motor 68 is selectively energized
by a conventional numerically controlled Z-axis servo system
(not shown) to move upright 66 to any desired position along
the Z-axis~ -
A set of vertical Y axis ways 70 are ~ormed on upright66 perpendicul~r to both X-axis ways 54 and Z-axis ways 64. A
spindlehead 72 is slidably mounted on Y-axis ways 70 an~ i~
driven there along by a conventional ballscrew dr~ve (not
sh~wn) which is powered by a servo motor 74 (Fig. 2)o ~.otor
74 is selectively energized by a conventional numerically con-
trolled Y-axis servo system (not sh?wn) to move spindlehead 72
to any des~red p~sition al~ng the Y-axis.
A hydraulically actuated counterweight system is
coupled to spindlehead 72 to take the weight of spindlehead
72 off the ballscrew drive therefor, The counter~eight system
in^ludes two hydraulic piston and cylinder mechanisms 76 (Fig.
l), two cables 78 which are coupled between hydraulic cyllnder
mechani~ms 76 and ~pindlehead 72, and pulleys 80 which guide
cables 78. Hydraulic p~ston and cylinder mechanisms 76 apply
a tension t~ cables 78 which is approximately equal and opposite
to the weight of spindlehead 72 to take the weight of spindle-
head 72 off the ballscrew drive,
A spindle 82 is rotatably mounted in spindlehead 72
and is adapted to receive ~onventional cylindrical shank tool-
holders and to clamp the toolholders to spindle 82 for rotatlon
therewith. Spindle 82 is driven in its rotary motion by a
spindle motor B4 (Fig. 2) through a set of conventional speed
change gears (Fig, 27). M~tor 84 is selectively energ~zed by
a conventional numerlcally controlled ~plndle motor control
(Fig. 40) to rotate spindle 82 at the desired sp,eed ~n the de-
sired direction to machine a work-piece 86 (F~g. 2) on a con-
ventional worktable 88 positioned in front o~ bed 50. The de-
talls of w~rkta,ble 88 are omitted since they are no~ relevant to
the automatic tool changer of this invention.
The automatic tool changer includes (l) a double
deck tool storage magazine 90 ~hich is adapted to ~tore a
plurality of ~ingle tools and/or multiple spindle toolheads
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with the shanks thereof ln a vertical position, (2) a tilt
unit 92 which is adapted to hold ~ne toolhead and to t~lt
the tool or toolhead by ~0 from a vertical posltion t~ a
hori~ntal position parallel t~ the axis of splndle 82 or
from a horizontal position to ~ vertical posltion, (3) a
first tool change arm assembly 94 which is adapted to trans-
fer tools and toolheads between tool storage magazine 90 and
tilt un~t 92~ (4) a second tool change arm assembly 96 which
is adapted to transfer tools and toolheads between tilt unit
92 and spindle 82, (5) coacting clamp and support means,.
described hereinafter, for supporti.ng eaeh multiple spindle
toolhead and holding it stationary while the shank and tools
thereof are ro~atlng with spindle 82, and (6) the hydraulic
and electrical controls) described here~nafter, required to
move the movable portions of components (1) to (5) above in
accordan_e with a predetermined sequence, described hereina~ter,
for transferring to~ls and/or toolheads from tool storage maga-
zine 90 to spindle 82 and vice versa.
The ~ndividu~.l components of the automatic tool
changer will be described in detail startlng wi~h tool storage
magazine 90. Tool storage magazine 90 is a double deck struc-
ture which supp~rts two endless chains 98 (Fig. 2) of tool and~
or toolhead sockets 100. Referring to Fig. ~, each tool soeket
100 has a hollow cylindrical body 102 which has a central bore
104 whieh ~s of a slze to receive.relatively large single tools
with cylindrical shank toolholder~ or relatively large multiple
spindle toolheads with cyl~ndrical shanks. ~ flange 106 is
formed on the top.of body 102 for supporting the flange 108
on a toolholder or toolhead whose shank is lnserted ~n bore 104.
Tool socket body 102 is bolted to a carrier 110 by
bolts 112. Carrier 110 is fastened to chain 98 by a pair
of support pins 114 which are fastened t~gether on thelr top
end by piece 116 and extend through ad~acent openings in
the links of chain 98. A snap fastener 118 engages the bot-
tom of ~ins 114 and secures them to chain 98.
At the bottom of tool ~ocket body 102, three rollers
120 (Fig. 6) are ~ournaled to flanges 122 with tw~ rollers
.120 on the outer side of ~ocket body 102 (to the right in
Fl~. 6) nd ~ne roller ln the lnner Rlde (t~ the left Ln Flg. 6).
,
Rollers 120 ride in covered channels formed by spaced plates
124 and 126 which are ~astened together by conventi~nal means
and are supported by conventlonal means.
Re~erring to ~ig. 3, both endless chains 98 are
~uided and driven around a double I,-shaped path by means o~
conventional sprockets, one Or which is shown in Fig. 6, and
- another of which is shown in Fig. 7. Sprocket 128 in Fig. 6
is ~ournaled for rotation on a vertical axle 129 between tWG
spaced support plates 126 and 130 by conventional means and
-- 10 is driven by a servo motor 132-which is also attached to
plates 126 and 130 by conventional means. Servo motor 132
drives a pinion 134 which is meshed with drive spr~cket 128.
Sprocket 136 in Fig. 7 is an idler sprocket which ls
~ournaled for rotation on a vertical axle 138 between spaced
support plates 126 and 130.
On the bottom of sprocket 136 (Fig. 7~ a plurality
of radially spaced stop lug~ 140 are bolted theret~ as a means
of counting and locating the tool sockets 100. Stop lugs 140
are spaced apart fro~ each other by the radial angle that
20 separates tool sockets 100. A first proximity switch 142 is
mounted on plate 130 and produces an output signal whenever one
of the lugs 140 passes over it~ A second proximity switch 144
(Fig. 6) is clamped tD plate 124 in position to coact with ~
downwardly pro~ecting tab 146 on one of the tool ~ockets 100.
Proximity switches 142 and 144 keep track o~ wh~ch
tool socket 100 is in po~ition t~ transfer or receive a tool.
The tool sockets 100 in the upper deck o~ this embodiment o~
the invention are numbered ~rom 1 to 29. When there is an out-
put signal ~rom b~th proximity switches 142 and 144, tool socket
3 number 1 is in position t~ trans~er or receiYe B t~ol. Each
subse~uent output signal from pr~ximity switch 142 means that
the next tool socket 100 ln the sequence-is in posltion to trans-
fer a tool. ~~ --
~` When the desired tool socket 100 is in position, m~tor
132 (Fig. 6) is de energized and cha~n 98 coasts t~ a ~top. A
pre~isicn loc~ting stud 148 (Fig. 7) is then raised by a hydraullc
piston and c~linder mechanism 150 into posltl~n to engag2 the near-
est lug 140. M~tor 132 i8 then energized ln the reverse direction'
t~ back sprocket 136 up until lug 140 and l~cating stud 148 abut
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against each other as shown in Fig. 7 which locates the
desired tool socket 100 in positlon to transfer or receive a
tool. Locating stud 148 is slidably mounted in a housing 149
and is moved by hydraulic pi~ton and cylinder'mechanism 150
between an upper position, shown in Fig. 7~ and in which stud
148 a~uts against the ad~acent sto,p lug 140, and a lower posi-
tion, ~n which stud 148 clears st~,p lugs 140. Stud 148 is
moved to its lower position be~ore motor 132 ~s energized in
the forward direction to move a difPerent tool socket 100 into
the tool transfer positlon.
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The tension in chain 9~ is ad~usted by an adjustable
idler sprocket 152 (Fig. 8) which is ~ournaled on a vertlcal
axle 154 ~n bearing housings 155 which are slidably mounted
on plates 126 and 130 by conventional'means. A pair of
threaded studs 156 carrying ad~ustment stop nuts 158 are screwed
-into threaded openings in housings 155. Stop nuts 158 abut
aga~nst slotted lugs 160 on plates 126 and 130.- The tension
in cha~n 98 can be adjusted by loosening or tightening nuts 158.
Fig. 5 shGws the suppo'rting structure for tool storage
20 magazine 90. The rear portion of tool storage magazine 90 (at
the right side of Fig~ 5~ is rollably supported on a stationary
'rail 162 by rollers 164 which are ~ournaled to a'base' 166.' Base
- 166 is attached to the lower plate 130 o~ *he lo~ler deck of tool
storage magazine 90. A group of spaced posts 168 extend between
the lower plate 130 of the lo~er deck and the lower pIate 130 of
the upper deck of tool storage ma~azine 900 The front portion
of tool storage magazine 90 (at the lef~ side of Fig. 5) is
slidably supported Dn bases 170 which extend from the adjacent
portion o~ X-axis bed 50 (Fig. 1). A base plate 1~2 is attached
30 to the adjacent end of the saddle 52 and slides over bases 170.
The front portion of tool magazine 90 is supported by base plate
172 and thus moves with saddle 52 over ~he X-axis bed 5~ and bases
- 170. Base plate.l72 also supports tool change arms g4 and 96
- and tilt unit 92 (see Fig. 23. Thus upright 66, tool storage
magazine 90, tool change arms 94 and 96 and tilt unit 92 all
move as a unit w ith saddle 52. '-
Referring to Fig. 2, a ~irst tool change arm assembly
94 trans~ers too'l~ from tool storage magazine 90 to tilt unit 92.
The details of the first ool change arm ~ssembly 94 ~re illus~rated
in Flgs. 10-17. Referring to Figs. 10 and ll, a tool gripper arm
174 18 rotat~bly mounted on a base 176 ~or rotatlon about a ~ertical
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axis 178 (Fig. 11). Tool gripper a~m 17 is r~tatable from a
- forward position, indicated in Fig. 10 by broken outline 174A,
to a central position indlcated in Fig~ 10 by the solid outline
174B, to a rear position indicated in Fig. 10 by br~ken outline
174C. In the rear p~sition, tool gripper ar~ 174 picks up a tool
or toolhead from tool storage ma~azine 90. In the central position~
. the tool or toolhead is placed in tilt unit 92. In the forward
._ position, tool gripper arm 174 is clear of tilt unit 92 so that
the latter can tilt forward. On the return portlon o~ the cycle, . 10 tool gripper arm 174 picks up a tool or toolhead from tilt unit
92 in the central position and transfers it to tool storage mag-
azine 90 in the rear position.
~~~~~~ ~~ ~` ` Tool gripper arm 174 is rigidly attached to a vertical
shaft 184 (Fig. 11) which is rotatably atta^hed to brackets 186
on base 176 by bear~ngs 1~8. .4 horizontal bracket 190 is ro-
tatably attached to sha~t 184 by bearings 192 and is moved by a
hydraulic piston and cylinder mechanism 194 (Fig. 10) which, in
its retracted position, moves arm 174 to its forward position, and
- .~hich in its extended position, moves arm 174 from its forward pos-
ition t3 its central position. The piston rod 195 o~ hydraulic
piston and cylinder mechanism 194 is connected to bracket 190 by a
pivotal connector 196. The other end of hydraulic piston and cy-
linder mechanism 194 is pivotally connected to a bracket 198 on
base 176.
. A bracket 200 (Fig. 11) is attached to a projection 201
of bracket 190 by machine screws 203. Bracket 200 provides a piv-
otal mounting for another hydraulic piston and cylinder me^hanlsm
202 which is plvotally coupled between brackets 190 and 2~0 by
trunnions 204 (Fig. 15). The piston rod 206 (Fig. 15) o~ hydraulic
piston and cylinder me_hanism 202 is pivotally coupled to a bracket
208.~Fig. 11) on tool gripper arm 174 by a pivotal connector 210.
Hydraulic piston and cylinder mechanism 202, when extended, moves
arm 174 from its central-position 174B (~ig. 10) to its rear posi-
tion, indicated by broken line outline 174C in ~ig. 10~ When
: . hydraulic.piston and cylinder mechanism 202 ls retracted, it moves
arm 174 from its rear position 174 C to its central position, in-
dicated by the sol~d line position 174~ ln Fig. 10. A pair of cam
actuated ~imit switches 212 and 214 (Flgs~.ll and 15~ indicate when
arm 174 is in the ~orward, central, or rear position~ L~mit swltch
21~ is actuated by cam 216 ~nd ~lmit æwitch 214 i~ actuated by cam
218. Both cams 216 and 218 are mountea on a shaft 219 which is
_ attached to sha~1; 184~ -
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A semicircular gripper cavity 220 (Flg. 10) is formed
in the end of arm 174. A pair o~ rollers 222 and a movable Jaw
member 224 are m3vably mounted in arm 174 and are positioned
around gripper cavity 220 in position to grip the grooved flange
o~ a toolholder or multiple splndle toolhead to securely hold the
toolh~lder or toolhead in arm 174 for trans~er. Movable ~aw member
224 is slidable in slot 226 in arm 17~ between an extended p~sition
shown in Fig. 10 and a retracted position (not shown) in which
~aw member 22~ is completely withdrawn into slot 226~ Jaw member
10 224 is moved back and forth between its extended and retracte~
positions by a hydraulic piston ~nd cylinder mechani~m 228 whlch
moves a slide 230 in a slot 231 (Fig. 12) crossways of ~aw member
224, Slide 230 has a raised cam portion 232 (Fig. 12) which ex-
tends at a 45 angle ~-~ to the edge of slide 230 and slidably en-
gages a cam slot 234 in ~aw 224. Cam slot 234 extends at the same
angle ~of 45 to the edge of ~aw member 224 and interacts with the
raised cam portion 232 of slide 230 to move ~aw member 224 between
its extended and retracted position.
When hydraulic piston and cylinder mechanism 228 is
20 extended, ~aw member 224 is retracted and when hydraulic piston
and cylinder mechanism 228 is retra^ted, as shown in Fig. 12,
~aw member 224 is extended.
The tip 236 (Fig. 12) o~ cam portion 232 and the ad-
~acent portion ~f slot 234 are angled at a small angle ~ to the
edge of slide 230 to provide ~or a reduced rate o~ movement at the
end of the retraction stroke of hydraulic piston and cylinder mech-
anism 228 to lock the toolholder or multiple spindle toolhead in
gripper jaw cavity 220. Movement o~ cam portion 232 along the edge
236 ~ill eontinue until ~aw member 224 exerts enough pressure on the
3o toolholder or toolhead therein to counteract the retraction force
of hydraulic piston snd c~llnder mechanism ~28.
- - Referring to Figs. 11, 13 and 14, the bottom of sl~t
226 in tool gripper arm 174 is closed by a cover plate 238 which
is attached to gripper arm 174 by machine screws ?40. The end of
slot 231 i8 closed by a cover plate 242 ~Fig. 13) whlch is attached
to gripper arm 174 by machine s~rews 24~. ~ limit switch 246
(Figs. 11 and 14) ls mounted on the bottom ~ cover plate 238 by
machine screws 248. A spring loaded plunger 250 ~F~g. 14) bears
against the bottom o~ gripper ~aw 224 and actuates switch 246
when gripper ~aw 224 i8 in lts retracted position.
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Tool gripper base 176 is slidably mounted for vertical
movement on an upright 252 (Figs. 10, 16 and 17). A set o~
vertical ways 254 ~Figs. 10, 15 and 17) are formed on upright
252 to guide the vertical movement of tool gripper base 176.
Two vertical movements are required ~or base 176. The first is
A short upward m~vement t~ lift a toolholder or to~lhead from
the tool storage socket 100 w1th which tool gripper arm 174
is aligned, along with the co~plementary short d~wnward movement
to lower a toolh~lder or toolhead intD the tool storage socket-~ 10- 100. The second vertical movement i~ a longer upward movement to
raise tool gripper arm 174 fr~m the lower deck of tool stor~ge
magazine 90 to the upper deck thereof, along with the ~mplementary
downward movement to lower tool gripper arm 174 ~rom the top deck
to the lower deck.
These two movements are obtained by two hydraulic
piston and cylinder mechanisms 256 and 258 (Fig. 16) which are
connected together in tandem, the base of the longer cylinder 258
being connected to, and supported by, the end of the piston rod
of the sh~rter piston and cylinder mechanism 256. The end of the
piston rod 260 o~ the longer p~ston and cylinder ~echanism 258 is
attached to a bracket 262 on the top o~ tool.gripper-base 176 by
a machine screw 264 (Figs. 15 and 16). Figs. 16 and 17 show the
longer piston and cylinder mechanism 258 in its fully extended pos-
ition and the shorter piston and cylinder mechanism 256 in its
fully xetracted posikion. This places tool gripper arm 174 in
p~sit~on to pick up a tool or too~head from the upper deck of
tool storage magazine 90. After the tool or toolhead has been
.gripped by gripper arm 174, lt is lifted out of its so~ket 100 by
extension of piston and cylinder mechanism 256. Then, after tool
30 gripper arm 174 has been swung-clear o~ tool storage magazlne 90
-both piston and cylinder mechanisms 256 ~nd 258 are retracted ts
`--. drop the tool or toolhead lnto tilt unit 92.
. With both piston and cylinder mechanisms 256 ~nd 258 ~.
`- retracted, tool gripper arm 174 is vertically po~tioned to grip
a toolholder or toolhead ~n the lower deck o~ tool storage magazine
90. An extension o~ p~ston and ~ylinder mechanism 256 will then
lift the grlpped toolholder or toolhead out of its socket 100. The
tool gripper arm 174 is then swung over tilt unit 92 (see Fig. 2)
'. and piston and c ylinder mechanism 256 is retrac~ed to drop the tool-
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holder or tool head into tilt unlt 92,
Four limit switches 266, 268, 270, and 272 (Fig. 17) are
mounted on uprlght 252 and interact w~th the ad~acent edge of
tool grlpper base 176 to indicate whlch of the four possible
- vertical positions that base 176 is in at any time.
~ Figs. 18~ 19 and ~0 ~how the details of tllt unit
-- . 92... A cylindrical tool socket 274 having an axis 275 (Fig. 18)
is attached to an arm 276 whlch ls pivotally attached to a pair
of upstanding triangular sides 278 by trunnions 280. Triangular
sides 278 are bolted to a base pl~te 282.
. ~. .. . . Socket 274 can be.pivoted from a vertical position9
shown in solid lines in Fig. 18, to a horizontal position,--
shown in broken llnes in Fig. .18, by extension ~nd retraction
of two hydraulic piston and cylinder mechanisms 284 which are
each pivotally connected at one end to base plate 282 and are
pivotally connected at the other end to socket 274. Within socket
274, a hollow cylindrical collet clamp 286 is slidably mounted
on a shaft 288. A stack of Belleville-springs 290 spring bias
c-ollet clamp 286 to ~ts clamped position. A short hydraulic pis-
ton ~nd cylinder mechansim ~g2 is mounted on the bottom of socket274 in position ror its piston rod 293 to bear against the end ~f
shaft 288 to move collet clamp 286 to its unclamped position.
Collet clamp 286 serves to clamp ~he cylindrical shank of a
toolholder or multiple spindle toolhea~ in socket 274.
A conventional cam operated limit switch 29~ (Fig.
18) is mounted on one of the trlangular sides 278 and is actuated
by _am 296 to indicate whether socket 274 is in its vertical or
hor~zontal p~sition.
F~gs. 21 to 26 illl1strate the details of the second
tool change arm assembly 96 ~Fig. 2) which exchanges tools or
toolheads between tilt uni~ g2 and spindle 82. Tool change
arm assembly 96 has a double ended tool gripper arm ~98 which
is rotatably mounted in an upright 300. Arm 298 is rigidly
. .~ atta^hed to a hollow sha~t 302 (Fig. 21) which is r~atably
mounted in upright 300 by conventional means ~not shown) and is
slidable along lts ~xis to move arm 298 between a rear position
shown in solid lines in Fi~. 21 and a forward positiQn shown in
broken lines in P`~g. 21.
Shaft 302 i8 circumferent~ally slot~ed at 3Q4 ts re-
ce~ve Q pair of rollers 306 (Figs. 21 and 24) which are mDunted
.
. .
: . .
. . -
: - ~31Z~45
-- 13 --
on a yoke 308. Yoke 308 is moved back and forth (right
and left in Fig, 21) by a hydraulic piston and cylinder
mechanism 310 whose piston rod 312 is rigidly attached So
. yoke 308. When pist~n rod 312 is extended, it moves arm 298
to the rear position shown by solid lines in Fig.. 21, When
piston rod 312 is retracted, it moves arm 298 to the forward
position shown by broken lines ln Flg. 21. The ~orce o~ pis-
ton 312 is communlcated to shaft 302 through yoke 308 and
rollers 306, which allow arm 298 to rotate in either its for-
_ 10 . ward or rear positions.
A spur gear 314 (Figs. 21 and 22) is rigidly at-
tached to the rear end of shart 302 and engages a ra~k 316
(Fig. 22) when shaft 302 is in its rear posi.tion, shown by
solid lines in Fig. 21. Rack 316 is moved up and down by a
hydraulic piston and cylinder me^hanism 318 whose piston rod
320 is attached to rack 316 and whose cylinder is attached
to a bracket 322 on upright 300 by mà`chine screws 324 The
~ull stroke of rack 316 rotates shaft 302 through 90 to
rotate arm 298 from its vert~cai position (shown in Figs.
1, 21 and 25) to its horizontal position (shown in Fig. 26).
The vertical position of arm 298 is the stand by position and
the horizontal position is the tool pick up or deposit position.
When shaft 302 and arm 298 are in their forward posi-
tion, shown by broken lines ~n Fig. 21, gear 314 is aligned
with a second rack 325 (Figs. 21 and 23) which ~s mo~ed by a
hydraulic piston and cylinder mechanism 326. The piston rod
328 of piston and cylinder mechanism 326 is attached to rack
325,.which is twice as lDng as rack 316 and rotates shaft
302 and arm 298 by 180 to interchange the ends thereofO The
30. rotation through 180 only occurs when shaft 302 and arm 298
are in their forward positlon, shown by the broken lines in
: -- Fig. 21.
- Limit switches 330 and 332 (Fig. 21~ are mounted on
..~ upright 300 by conventlonal means and are actuated by plungers
334 and 336.to indicate whether arm 298 is ln the forward or
rear position. A limit switch 338 ls mounted on the housing 340
~or rack 3~5 and interacts with a plunger 342 to ind~cate whether
arm 298 is in a posLtion to pi~k up tools or toolheads or to
~eposit t~ols or toolheads.
Tool gripper arm 298 IFigs. 25 and 26) has opposed
. to~l gripper ca~ties 344 and 346 which contain rollers 348
..
.
.
- J4
: Rollers 348 are dimensloned and positloned t~ fit in a stand-
ard grooved ~lange on a toolholder or multiple spindle tool-
head. A pair of rotary tool gripper jaws 350 and 352 are
rotatably attached to arm 298 adjacent to gripper cavities
344 and 346. Tool gripper ~aws 350 and 352 have gr~pplng
segments 354 and 356, respectively, which are shaped to enter
- the grooved flange on ~ toolholder or multiple spindle tool-
head. Gripper ~aws 350 and 352 are spring biased by torsion
springs 358 (FigsO 31 and 32) to urge gripp~ng segments 354
and 356 away from tool cavities 344 and 346, respe~tively.
The movement of gripping segments 354 and 356 away from tool --
cavities 344 and 34~ is limited by the abut~ent of the straight
edges 370 and 372 of gripper jaws 350 and 352 with stop p~ns 362
and 364, respectively.
A-cam 360 with an open position shown in solid lincs
in F g. 25 and a locked position shown in broken lines in Fig. 25
is rotatably mounted between gripper jaws 350 and 352. In the
locked position shown in Fig. 26, both gripper ~aws 350 and
352 are rotated toward their respective tool cavities 344 and 346
to insert tool grip segments 354 and 356 into the grooved flange
of toolholders 366 and 368, respect~vely. In the p~sition shown
in Fig. 26, both to~l gripper ~aws 350 and 352 are locked in the
position shown by cam 360, which abuts against the straight edges
370 and 372 on jaws 350 and 352, respectively. This locks tool-
holders`366 and 368 in tool ^avitles 344 and 346, respectively.
- Cam 360 is mounted to be able to flaot laterally to equalize
calmping pressure. To release toolholder 366 and 368, cam 360
must be rotated 90 degrees counterclockwise ~rom the posit~on
shown in Fig. 26 ba^k to the p~sition shown in solid lines in
Fig. 25. This permits tool gripper ~aws 350 and 352 to rotate
counterclockw~se in Fig. 26 away ~rom tool cavities 344 and 346,
respectively.
Referring to Figs. 21 and 26, cam 360 is attached to a
shaft 374 (Fig. 21) which extend~ throu~h the hollow interior --
of shaft 302. The rear end of shaft 374 (on the right side o~
Fig. 21) is comqected to a hydraul~c rotary actuator 376 ~uch
as manu.actured by the Flo-Tork Companyj, Oville, Ohio, U.S.A.
Rotary actuator 376 acts to rotate shaft 374 by gOc clockwisc
or counterclockwise in res~onse to electrical signals. 90
rotation o~ shaft 374 rotates cam 360 be~ween lts Dpen and IGcked
.
~",. . .
. .
Z~5
po~ition as described previously.
Toolholder 366 in Fig. 25 is in spindle 82 while tool-
holder 368 is in tilt unit 92. To exchange toolholders 366 and
368, upright 66, saddle 52 and spindlehead 72 are moved by the
N.C. axis servo systems to the positions shown ln Flgs. 1 and 2.
Tool change arm 298 is then rotated 90 counterclockwlse from
the position shown in Flgs. 1 and 25 to the position shown in
Fig. 26. As tool cavities 344 and 346 approach toolholders
366 (Fig. 25) and 3683 the latter c:ontact ~lat edges 378 and 380
-10 o~ gripper ~aws 350 and 352 and cause them to rotate to move
gripper se~ments 354 and 356 lntD the grooved flange of tool-
holders 366 and 368. Grlpper segments 354 and 356 are then
locked ~n position by rotating cam 360 by 90 counterclockwise
to the position shown in Fig. 26.
To unlock gripper ~aws 350 and 352, cam 360 ls ro-
tated 90 counterclockwise in Fig. 26, wh1ch releases grip-
per jaws 350 and 3~2 to rotate away from toolholders 366
and 368 under the urging o~ their respective tcrsion springs
358 (Figs. 31 and 32).
Although the operation of tool change arm 2~8 has
been described in connection with tools on both ends of the arm,
- It w~ll work as well with a single tool at either end of the
arm.
Referring ~o Fig. 27, spindle 82 is rotatably mounted
w~thin splndlehead 72 by bearings 384 and ls driven by a con-
ventional speed change gear set 386. Spindle 82 is hollow and
contains a drawbolt 388 rotatably mounted therein and adapted
to be rotated by a conventional drawbolt motor and clutch ar-
rangement which are not shown in the drawingsO Drawbolt 388 is
3 threaded at its front end 390 to fi~ into a threaded opening
- in the cylindrical end of a toolholder or multiple spindle tool-
headO
A collet clamp 392 with a cylindrical socket is at-
~ tached to the front end o~ a hollow collet tube 394 which lieswithln the hollow interior o~ spindle 82 and e~close~ drawbolt
388. ~ollet tu~e 394 i8 axially slidable with respect to spindle
82 and dr~wbolt 388 and is axially shi~te~ between an open and
a clamped position o~ collet 392 by a hydraulic pi~ton and cyllnder
mechanism 396 (on the right side o~ Fig. 27). The piston rod 398
. ~ . . .
of plston and cylinder mechanism 396 acts on a lever arm
400 which is pivotally connected to spindlehead 72 by pin
402 and has a cam 404 which pushes or pulls on collet tube
394 when lever arm 400 is rocked by hydraulic piston and
cylinder mechanlsm 396. Colle~ clamp 392 cIamps the toolholder
shank or toolhead shank to splndle 82 to prevent the toolholder
from being dislodged when drawbolt 388 ~s screwed thereinto.
Collet clamp 392 also centers the toolholder shank.
A novel clamp and support means is used to clamp
relatively heavy (e.g. l,OOO pounds) multiple spindle tool-
.. . .. .. . .. . ... . . , . .. ... . . .. . .. . . .. . . . , . .. . . . .. ~ .. . . .. .... . ... .. .
heads 405 (Fig. 33' to spindllehead 72 to support the t~o~-
head 405 and hold it stationary while its shank 406 and
tools 408 are rotating wikh sp~ndle 82.
Toolhead 405 has a body 497 in which a plurality o~
spindles 498 are journaled. Spindles 498 are rotated by con-
ventional gears 499 which are coupled between spindles 498 and shank
406, which is journaled ln body 497 and flange block 503 by bear-
ings 500. Body 497 has a backplate 501 with a central opening
502 through which shank 406 passes.
A flange bl~ck 5~3 is attached to backplate 501 by
bolts 504 and extends rearwardly ~rom backplate 501. Flange
block 503 is cylindrical in shape and has t~e same outside
dia~eter as the flange 44B (Fig. 39) of an individual tool-
holder which i9 dimensioned to be gr~pped by the tool changer
arms 174 (Fig. 1) and 298 described previously, Flanges 448
and 503 have V-grooves 450 (Fig~ 393 and 452 (Fig. 33) which
- have the same dimensions and are dimensioned to be gripped by
the above-noted tool changer arms 174 and 298. Flange block
503 has a rear M ange ~n the rear portion thereof-for supporting
tooIhead 405 as described below.
Four threaded studs 410, each having two opposed
flats 412 (~igs. 36 and 38) ground on lts threaded end, are
rigidly attached to clrcumferentially spaced openings 414 in
- rear flange 416 tFig. 33) of each multiple spindle toolhead
405. ~i~. 38 shows a perspective view Qf one o~ the studs 410.
The head 418 of stud 410 'L Dblong in shape and has two holes
420 for receivLng machine ~crews 422 (not visible ln Fig. 33)
which rigidly fasten stud 410 to flange 416. Although only one
stud 410 ls visible ~n ~ig. 33, it will be understood that the
other three are positioned at circumferential positions that are
...... .. . .
: .
'~.
~L~Z~Z45
~, .
- 17 - _
n~t cut by the plane of Fig. 33.
A guide pin 424'(Fig. 33) which is attached by con-
ventional means to flange 416 coaets with a guide ~pening 426
in spindlehead 72 to correctly align studs 410 with the threaded
open ngs 428 (Fig. 35) into which studs 410 are inserted. Open-
ings 428 have slotted sides 430 whlch receive the threaded por-
- tlons of studs 410 while the flats 412 of stud 410 pass by the
threaded portions ~f opening 428. Threaded openings 428 are
each formed ~n a ~ollar 432 which is rotatably attached to
spindlehead 72 (Fig. 33). Each stud 410 is locked in the cor-
responding collar 432 by rotating collar 432 by 90 afte~ stud
410 is inserted in opening 428. The 90 rotation of collar 432
engages the threaded portion of stud 410 with the threaded por-
tion of opening 428.
~ igs. 34 and 37 show the means for rotatlng each
collar 432 to lock the corresponding stud 410 therein. Collar
432 is attached to a shaft 434 (Fig. 34) which is rotatably at-
tached to spindlehead 72 by bearings 43~. A ball screw thread
438 is formed on shaft 434 and engages a ball nut 44~. A hydraulic
piston and cylinder mechanism 442 is coupled to ball nut 440 by
conventional means and pushes or pulls ball nut 440 axially a-
long ball screw thread 438 far enough to cause shaft 434 to ro-
tate ~y 93, thereby rotating collar 432 by 90 to effect the
locking a^tion described above. The ball screw turn-lock
mechanism described above has the advantage of being slender
enough in its lateral dimensions t~ ~it in the limited space
available in spindlehead 72 outside of spindle 82.
Fig. 39 shows a boring bar 444 which is adapted to be
handled by the previously described automatic tool changer
and to be clampe~ ln spindle 82. The shank 446 o~ boring bar
444 has the same dimensions as the shank 406 of multiple spindle
toolhead 405. Boring bar 444 has a flange 448 with a V-shaped
gr~ove 450 therein. Groove 450 has the same d~mensions &S the
- V-shaped groove 452 (Fig. 33) in multiple spindle,toolhead 405.
The only difference ln using boring bar 444, or some other single
tool, in place o~ multiple spindle toolhead 405 is that with a
single tool it is not necessary to turn collars 432, and since
cQolant could get lnto openings 428 o~ collars 432 when they
are n~t used, a circular shield 454 (Fig. 29) is rotatably
.
. :~
- lB -
attached to spindlehead 72 to normally c~ver openings 428 as
shown in Fig. 29.
When a single tool is used, shield 454 covers open~
ings 428~ but when a multiple spindle toolhead ~s used, sh~eld
- 454 ~s rotated by an angle ~ to place openings 456 over openings
428 to expose them to receive studs 410 as described previously.
Shield 4~4 is rotated by downward movement of a pin 458 on the
side of shield 454 ad~acent to upright 300, which supports tool
change arm 298. Each time tool change arm 298 is moved to lts
10 ~orward posltion, described previously, an arm 460 which is
..... . . ..
swingably mounted on upright ~?,oo moves to the position shown in
broken lines in Fig. 29 and engages pin 45~ in a slot 462 on a
bracket 464. Bracket 464 is coupled to a hydraulic piston and
cylinder mechanism 466. When a multiple spindle toolholder is
about to be transferred into spindle 82, piston and cylinder
mechanism 466 is extended to drive b`racket 464 and pln 458 to
the lower pDsition shown ~n broken lines in Fig. 29. This
exposes openings 428. When a single tool is about to be
transferred into spindle o2, piston and cylinder meehan~sm
466 is not extended and openings 428 remain covered.
The mechanism for movlng arm 460 between the two
positions shown ~n Fig. 29 is shown in Fig. 28 and 30. Arm
460 is pivotally attached to upright 300 by a pivot pin 468.
Another arm 470 is rigidly attached crossways to arm 460 and
~s plvotally attached to a slide 472 which is slidably mounted
in a housing 474 ~ig. 28) on upr~ght 300. Slide 472 is connected
by pin 476 (Fig. 28) to yoke 308 (Fig. 24) wh~ch moves tool change
arm 298 between its f'orward and rear positions. Every time
to~l change 2g8 ls moved forwardly, pin 476 pushes sl~de 472
forward which causes arm 460 to rotate about pin 468 as shown
in Fig. 28 and described previously.
An illustrative tool change cycle will now be de-
-~ scribed step 4y step beginning with the rollowlng initial con-
-` ditions: -, ~
(A) A boring bar 44 (Figo 39). is clarnped in
spindle 82 and ~ being used to machine ~ workpiece 86 (Fig.
2) on worktable 8E3.
- (B) The empty tool socket 100 ~or boring bar 44 is
at the tool tran~f'er position in the upper deck of tool stora~5e
magazlne 90 and locating stud 148 is l~wered.
....... .. .
': . ' ; ;
: . ,.
S
-- 19 -- _
(C) The next tool to be used is a multiple sp~ndle
toolhead 405 (Fig. 33) which is in a socket 100 ln the upper
deck o~ tool storage magazine 90 Ln a known position.
(D) Tllt unit 92 is emp~y and is in the vertical
pos itionO
(E) Tool change arm 174 is empty and is in the
oentral position opposite the lower deck of tool storage maga-
. zine 90.
~ F) TOD1 change arm 29B is empty on both ends and10 is in the vertlcal rear position.
.. .. .. .. . . . .. . . . . .. .. . . . . . .. .. . .. . . .. . . . . .. . . . . ......... .
Under the foregoing initial conditions~ the toSol
change cycle will proceed as follows:
(1) While the workpiece 86 is being machined,
motor 132 (~ig. 6) of the upper deck of tool storage ~agazine
90 is energized in the forward dire^tion to move tool sockets
100 past the tool transfer position shown at point 478 in Fig,
2.
(2) The number of times that a lug 140 (Fig. 7) pass-
es over proximity switch 142.is counted by a con~entional
counter (not shown) until the known position of the tool socket
100 containing the desired toolhead 405 is at tool transfer
point 478. If, for example~ the empty tool socket 100 for
the tool in use i~ tool socket Number i5 and the toolhead 405
to be used next is in tool socket Number l9~ the desired tool
~ill be at the tool trans~er poLnt 478 on the ~ourth output
pulse o~ proximity switch 142.
(3) When the desired tool is at the tool transf'er
point 478, motor 132 (Fig. 6) i.!; de-energized and coasts to
a stop. This places the desired tool socket sl~ghtly past
tool trans~er point 478.
(4) Hydraulic piston and cylinder mechanism 150
(Fig. 7) is extended to raise locating stud 148 as shown in
Fig. 7.
-, (5) Motor 132 (Fig. 6) ls energized.~or slow ro~
tation in the reverse direction to move lug 140 ~gainst locat-
lng stud 14B and locate the desired tool socket 100 at tool
transfer point 478. Motor 132 is allowed to stQll in the re-
verse dire^tion t~ hold lug 140 ~galnst locQting stud 148.
(6) Hydraulic piston and cylinder mechanLsm 258
(Figs. 16 and 17) is extended to raise tool change ar~ 174
s .~
- 20~_ .
to the level of the upper deck ~ tool storage magazine 90. .
(7~ Hydraulic piston ~nd c~linder mechansim 202
(Fig. 10) is extended to move tool change arm 174 to tool
trans~er point 478. This places tool cavlty 220 (F~g. 10)
around the V-groove of the desired toolhead 405.-
(8) Hydraulic p~ston and cylind~r mechanism 228~Flg. 10) ls retracted to move gripper jaw 224 into contact
with the V-groove of toolhead 405 tQ clamp lt t~ arm 174.
- (9) Hydrauli^ piston and cyllnder mechanism 256
~Figs. 16 and 17) is extended to li~t toolhead 405 out.
tool socket 100.
~ 10) Hydraulic piston arld cylinder mechanism
292 (Fig~ 18) is extended to open collet-clamp 286 in tilt
unit 92,
(11) Hydraulic piston and cylinder mechanism 202
(Fig. 10~ is retracted to swing toolhead 405 over tilt socket
27~. - .
(12) Hydraulic piston and cylinder mechanism 256
(F~g. 16) is retracted to lower toolhead 405 into tilt socket
274 of tilt unit 92.
(13) Hydraulic piston and cylinder mechanism 228
tFig. 10) is extended to release gr~pper ~aw 224 from tool-
head 405.
(14) Hydraulic piston and cylinder mechanism 292
(Fig. 18) is retracted to close collet clamps 286 of tilt unit
~2.-
(15) Hydraulic piston and cyllnder mechanism 194(~ig. 10) is retracted to swing tool change arm 174 to its
forward pos~tion.
3 (16) Hydraulic pi~ton and cylinder mechanisms 284
(Figs. 18 and 19) are extended to swing tilt socket 274
- and toolhead 405 to the horlzontal position.
- The ~oregoing steps 1 to 16, or any desired portion
thereof, can be performed while workpiece 86 (Fig. 2) 1s being
machined with the tool placed ln sp~ndle 82 during the pre-
ceding tool change. Step 17, howeve~, cannot be performed until
the current machining operation on workplece 86 is completed.
(17) The X, Y and Z axes drlves for the machine tool
are actuated to bring Ispindle 82 into the tool change position
6hown ln Flgs. 1 and 2 and 6plndle B2 ls 6topped.
~ .
.: ,
32~5
-- 21---
(18) Hydraul~c piston and cylinder mqchanis~ 318
(Fig. 21) is extended to rotate ~ool change arm 298 by 90
from the vertical tt~ the horizontal position.
(19) Hydraulic rotary actuat~r 376 (Fig. 21)
is rotated c~unterclo^ksYise 9oD to lc~ck cam 360 (Flgs,. 25
and 26) against tool grip ,~a,ws 350 and 352.
(20) Piston and cylinder mechanism 398 (~ig. 27)
is extended to open collet clamp 392 in spindle 82.
(21~ Piston and cyllnder mechanism 292 (Fig. 18~
is extended to open collet clamp 286 in tilt unlt 92.- - - - -
(22) Piston and cylinl:ler mechanism 310 (~'ig~
~s retracted to pull to~l 444 out Gf splr~dle 82 and toolhead
405 out o~ tilt s~cket 274.
(?3) Plston and cylinder mechanism 326 (Fig. 21) is
extended to rotate tool ~hange arm 298 by 180 to interchange
tool 444 and toolhead 405.
(24) Piston and cylinder mechanism 466 (Fig. 29
~s extended to move openings 456 over lock openings 428.
(25) Piston and cylinder mechanism 310 tFig. 21)
is extended to insert toolhead 405 into spindle 82 and ~ool
444 into til~ socket 274.
(26) Piston and cylinder mechanisms 442 (Fig. 34)
are extended to rotate locking co:'llars 432 by 90 to lock studs
410 therein.
(27) ~ydraulic rotary actuator 376 ~Fig. 21) is ro-
tated clockwise 90 to unlock cam 360 (Figs. 25 and 26) from
toDl grip jaws 350 and 352.
(28) Hydraulic piston and cylinder mechanism 39
(Flg. 27) i~ retracted to close collet clamp 392 in spindle
iB2.
(2~) Hydraulic piston and cyllnder mechanism 292
(~ig. 18) is retracted to close collet clamp 286 in tilt unit
92.
(30) Piston and cylinder mechanism 318, (Fig. 21~
is retracted to rotate tool change arm 298 ~rom the horizontal
to the vertical pcsition. After this step, mach~ning o~ the
workpiece can begin ajgain with the new tool.
(31) Pistorl and cylinder mechanisms 284 (~ig. 18)
are retracted to tilt boring bar 444 and tilt socket 274 to the
` ' vertlcal position.
.
.
i124S
- 22 -
(32~ Piston and cylinder mechanism 194 (Fig.
lO) is extended to swing tool change arm 174 over tilt s~cket
- 274.
(33) Piston and eylinder mechanism 228 ~Fig. 10) is re~
- tra~ted to move gripper jaw 2~4 ~nto c~ntact with boring bar
~44.
- (34) HydrauIic piston and cylinder mechanism 292
(Fig. 18) is extended to open collet clamp 286 in tllt un1t
92.
- ~-~~ l~-------- ---- --- - (35) Piston and cylinder meehanisms 256 and 258 (Figs.
16 and 17) are both extended to raise boring bar 444 ab~be the
level of the upper deck of tc~l storage magazine gO,
- (36) Piston and cyiinder mechanism 202 (~ig. lO)
is extended.to move boring bar 444 to exchange p~sition 478.
(37) Piston and cylinder mechanism 256 (Fig. 16
and 17) is retracted to drop boring bar 444 into tool socket
100.
~ 38) Piston and cylinder mechanism 228 (Fig. lO)
~s extended to moYe gripper ~aw 224 out of contact with boring
bar 444.
(39) Piston and cylinder mechanism 202 ~Fig. lO)
is retracted to move tool change arm 174 to its central po-
sition.
This completes the tool change cycle ~or the par-
- ticular tools involved.
Figure 40 is a block diagram of the electrical cir-
cuits which control the operation of the ma~hine tool. Standard
coded instruction signals are punched on a punched tape 480
and include sienals indicating which tools to use, ~hen the
tools should be changed~ and detailed speed and positioning
~nstructions for spindle 82 to perform the desired machining
-~ operations9 along with any other ~unc~ions tsuch as coolant
` flow) whlch are necessary ~or the operation of the machine tool.
~` - The instruction signals are read cff tape 480 by,a tape reader
482 an~ are applied to a computer 484 which controls the opera-
tion of the machine tool through a conventiona~ three axes driYe
-system 486, a clDnYentional spindle drive system 488 and other
c~nventional machine tool circuits (not shown) which do not
~nteract with tlhe automatic tool changer o~ this invention.
The foregoing tool change sequence is oontrolled bY
, . . : ..
. :
- :
z~
- - -
- 23 -
a suitable tool change computer routine 490 in c~mputer 484
which controls the sequential actuation of tool change sole-
noid valves 49~ to actuate the tool change piston and cylinder
mechan~sms 494 in the above described sequence Although sole-
noid valves 492 are not shown individually, it will be under-
stood by those skilled in the art that one solenoid valve is
lncluded in the clrcuit for each of the piston and cylinder
mechanisms described herein and illustrated in ~ig5. 1 to 39.
Each p~st~n and ~ylinder mechan~sm is either extended or re-
tra~ted in accordance with the state of the corresponding sole-
noid valve. The state of all of the solenoid valves 492 at a~y
glven time is controlled by tool change routine 49~ in accordance
with well known prior art programming practice t~ a~hieve the
sequen_e of-actuat~on described above in tool change steps 1 to
39. - _ .
Tool change limit switches 494 are coupled to tool
change components 496 in accordance with well known prior art
electrical control practice to indicate when the desired m~ve-
ment of a tool change c3mponent has been completed. The electri-
cal control portions of the machine tool are entirely conventionalwith the exception Or the actuation sequence.described above in
tool change steps 1 to 39. Accordingly, the details of the
electrical control circuits are rlOt described herein.
Although the illustrativè embodiment of the invention
has been described in considerable detail for the purp~se of
fully disclosing a practical operative structure incorporating
the invention, it si to be understood that the particular ap-
paratus shown and described is intended to be illustrative only
and that the various novel features of the invention may be in-
corporated in other structural ~orms with out departing from thesplrit and scope o~ the invention as defined in the subjoined
- claims.
- . .
.
