Патент USA US2559434

July 3, 1951
M. A. HOLLENGREEN ETAL
2,559,431
WORK LOCATING DEVICE
Filed Nov. 25, 1949
5 Sheets-Sheet 1
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July 3, 1951
M. A. HOLLENGREEN ETAL
2,559,431
WORK LOCATING DEVICE
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July 3, 1951
M. A. HOLLENGVREEN ET AL
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WORK LOCATING DEVICE
Filed Nov. 25, 1949
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M. ‘A. HOLLENGREEN ETAL
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M. A. HOLLENGREEN ETAL
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WORK LOCATING DEVICE
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Patented July 3, 1951
2,559,431
UNITED ' STATES PATENT OFFICE
2,559,431
WORK LOGATING DEVICE
Milburn A. Hollengteen and Donald F. Price,
Waynesboro, Pat, assignors to Landls Tool Com
Dally, Waynesboro, Pa.
Application November 25,- 1949, Serial No. 129,422
9 Claims. (0]. 51-—165)
2
This invention relates to apparatus for use in 5
connection with grinding or machining of cylin
Figure 2 is a left-hand elevation, partly in sec
tion.
Figure 3 is a plan view.
Figure 4 is an enlarged plan view of the work
drical portions of a work piece between ?anges,
cheeks, shoulders or other portions of greater
diameter adjoining the surface to be machined. 6 engaging unit.
Figure 5 is an alternate arrangement.
‘More particularly, this invention relates to ap
paratus for relatively positioning successive por
Figure 6 is a front elevation, partly in section,
showing the invention applied to the grinding
tions of a work piece and a cutting tool when
the machining must be done simultaneously on
wheel instead of the work carriage.
the spaced shoulders or ?anges as well as the
Numeral l0 indicates a crankshaft mounted on
cylindrical surface. This requires that the por
footstock center II and headstock center l2 for
tion to be ground or machined and the tool must
be accurately centered relative to one another
grinding the main bearings l3, I4, and I5. The
crank could just as well be mounted in eccentric
clamping ?xtures which are well-known in the
15
art for grinding the crankpins. The locating ap
equal amount of stock from each shoulder. When
paratus would function in the same manner to
so centered, the several portions will be accu
so that the tool will remove an approximately
rately positioned with relation to other similar
locate the crankpins relative to grinding wheel
l6 as it does to locate the main bearings.
portions on the same work piece.
When a rough cast or forged crankshaft is
Crank l0 and centers II and I2 are mounted
turned or milled, the spacing between bearing 20 on carriage 20 in a manner well-known in the
art but not disclosed in the drawing.
surfaces is not held to close limits. When it is
placed in a crank pin grinder having a spacing
Carriage‘ 20 may be moved endwise by means
bar and plunger, the spacing of the pin bearings
usually does not agree exactly with the notches
of a piston 2| and cylinder 22 connected by piston
rod 23 to a portion 24 in the lower side of said
carriage. Fluid under pressure is supplied al
on said spacing bar and a relative axial adjust
ternately to opposite ends of cylinder 22 . by
ment must be made between the work and the
means of a reversing valve 25. Said valve may
grinding wheel so that the grinding wheel will
be actuated automatically in a manner such as
grind equally on each shoulder.
It is, therefore, an object of this invention to
disclosed in Patents 2,105,841 and 2,323,189.
provide means for effecting relative axial posi 30 However, for the purpose of illustration, the
lever 26 is su?icient.
tioning between the tool and the ?anges or shoul
Fluid under pressure is supplied to valve 25 by
ders of a Work piece.
pump 30 through line 3|. A relief valve 32 con
It is a further object to provide a work engag~
ing device having means for engaging the spaced
nected to the outlet of said pump serves to reg
35 ulate the pressure in the hydraulic system. The
shoulders or ?anges of a work piece.
It is a ‘further object to provide means for
above-mentioned patents also show ‘automatic
means for indexing a work carriage. It is suffi
urging the work engaging means toward the work
surface in order to properly engage the shoul
cient for our purpose to show spacing bar 35 ad
justably mounted on carriage 20 by means of
ders or ?anges.
It is a further object to provide a preliminary 40 screws 36 in longitudinal slots 31 in said spacing
and approximate positioning operation supple—
bar.
mented by a more exact ‘positioning opera~
On the lower side of said spacing bar is a
plurality of notches 38 spaced to correspond to
tion.
the spacing of the portions to be ground on the
A further object is to locate successively a se—
ries of portions on a work piece in operative rela 45 work piece. A plunger 39 in the form of a piston
tion to a cutting tool.
.rod having a piston 40 attached thereto and op
The drawings show a diagrammatic arrange
erable in a cylinder 4| is held in engagement with
the spacing bar 35 by means of a spring 42. Said
ment of a, work piece in the form of a crankshaft
having a plurality of spaced portions to be
plunger may be withdrawn from said spacing
ground, as well as hydraulic and electrical sys-‘ 50 bar by ?uid under pressure directed through
terns for causing a locating movement between
line 43 from valve 44.
~
Said ?uid under pressure is supplied to said
the work and the tool and the apparatus for
accurately locating said parts after each index
valve from line 3| through lines 45 and 46. In
ing operation.
the drawing, valve 44 is in a position to direct
Figure 1 is a combined hydraulic and electrical 55 ?uid from piston 40 through line 43 to exhaust
diagram.
passage 41. Valve 44 is held in this position by
' 2,559,481
4
3
spring 48. Said valve maybe moved by lever 49
to connect pressure line 46 with line 43.
The means for engaging the work piece con
sists of a scissorslike member 60 having two ele
ments 6| and 62 pivoted at 63 and supporting
plates 64. Each of said elements has a circular
opening back of the pivot point through which
a pin 65 of smaller diameter passes.
Said pin is
toward and from operative relation to the work
piece. Movement may be e?ected manually, by
power manually controlled, or automatically.
For illustrative purposes, we disclose said housing
mounted on parallel flat springs I40 and Ill,
which in turn are mounted on a base member
I42. With this arrangement, the operator may
push housing 66 forward to operative position,
hold it there until the locating operation is com
mounted in a housing member 66 at one side
of said work engaging member and passes 10 pleted, and then release it so that the springs
tI40 and “I may return it to inoperative posi
through a cover plate 61 at the other side of said
work engaging member.
The portion of element BI and 62 opposite the _
work engaging end is made so that together they
form an inverted V. A pin ‘I0 engages the sides
of said V. Said pin is mounted in a piston ‘II
in a cylindrical opening 11 in housing 66 and is
urged into engagement with the sides of said V
ion.
In order to permit spring "I5 to function at the
proper time, a valve I50 vis located in any suit
able position to be actuated by the forward move
ment of housing 66. Said valve has a stem I5I,
which is engaged by a portion of housing 66 as
it moves toward operative position. Said move
ment shifts valve I50 against spring I52 to con
by spring ‘I5. When so urged, said pin tends to
actuate members SI and 62 so that the work 20 nect the end of cylinder 11 through line ‘I6 with
an exhaust passage I53. When housing 66 is re
engaging portions, consisting of two hardened
leased to returnto inoperative position, valve I50
surfaces 68 and 69, engage one or the other of
is shifted by spring I52 to connect line ‘I6 with
opposed shoulders 80 and BI on work piece I0.
line I55, which in turn is connected to line 45
For example, when surface 69 engages‘ shoulder
to direct ?uid under pressure to shift piston ‘II
8|, it is an indication that the work piece is too
against spring ‘I5 and move pin ‘I0 out of contact
far to the left to be engaged properly by the
with the feeler elements 6I and 62.
grinding wheel. Engagement between these two
In Figure 6 is disclosed an alternate method
surfaces will cause pivot 63 to move to left and
of effecting relative lateral or axial adjustment
the entire work engaging assembly 64 to move
in a counterclockwise direction about pivot 65. 30 between a grinding wheel and a shouldered work
piece. This method involves endwise adjustment
Said piston and feelers are reset by introducing
of the grinding wheel. Grinding wheel I6 is
?uid under pressure ‘from line 16 to the opposite
rotatably supported on a wheel base I60 by means
end of cylinder 11.
.
of a spindle I6I, which is rotatably mounted in
Members GI and 62 are normally held in a
suitable bearings in said wheel base. Bracket
centrallposition by springs 85 and 86. Oscillat
I62 engages the rotatable portion of the wheel
ing movement of the work engaging assembly is
mounting in any suitable manner for the purpose
limited by adjusting screws Y90 and 9I, which are
of effecting a slight endwise movement thereof.
positioned to engage the sides of plate member 64.
Said bracket should be connected to the wheel
Said plate member has an extended portion 92
mounting
at a point as close as possible to the
which passesbetween the feelers 95 and 96 of
grinding wheel so as to eliminate variations in
two indicator members 91 and 98 of the type dis
the position of the wheel due to expansion of the
closed in co-pending application Ser. No. 773,388,
spindle during operation.
?led September 11, 1947, which issued as Patent
_ At the upper portion of said bracket, there is
No. 2,533,770, each of which has an air valve I00
operable in conjunction with the actuation of the 45 inserted a bearing cartridge I63 having anti
friction bearings I64 in which one end of a shaft
indicator as described in said application.
I65 is supported. Said shaft extends through a
Each of said air valves receives a supply of
sleeve I66, one end of which is rotatably and
?uid under pressure which is permitted to escape
slidably mounted in a bracket I6‘I having sleeve
when said valve is actuated by extended portion
92. Said ?uid under pressure is conducted from 50 type anti-friction bearings I68 therein. Said
bracket is mounted on wheel base I60. The
any suitable source through lines IOI or I02. A
other end of said sleeve is supported in a similar
manometer tube I05 is connected to line IOI and
manner in bearings I69 mounted in a sleeve I10.
tube I06 is connected to line I02 through Venturi
Said sleeve, in turn, is mounted in a hollow cylin
devices I01 and I08. These devices as well as
their relation to the manometer tube are dis 55 drical portion III on wheel base I60. A portion
of sleeve I10 extends beyond housing III and
closed in greater detail in Patents 2,001,447, is
has a radial cylinder I80 formed thereon. Piston
sued May 14, 1935, and 2,019,066, issued October
I8I in said cylinder is urged outwardly by means
29, 1935.
'
.
of spring I82. A piston rod or clamp I83 pro
Contacts H0 and H4 in tube I05 and III and
I I2 in tube I06, when engaged by the mercury 60 trudes from said cylinder into engagement with
a slot I84 in sleeve I66. Said clamp may be held
column, serve to initiate operation of motor I20
in operative position by ?uid under pressure
on carriage 20 in a direction depending upon
directed to the head end of cylinder I80 from
which manometer tube is functioning. Said mo
pump 30 through line I85.
tor operating through worm gear I30, worm wheel
At the other end of sleeve I66 is a means for
I3I, screw I32 rotatably mounted in 9. lug I33 65
effecting axial adjustment between said sleeve
on spacing bar 35 causes carriage 20 to move
and shaft I65 and, therefore, between the wheel
relative to spacing bar 35, which is held in posi
shifting mechanism and the work locating mem
tion by plunger 39, to effect a substantially exact
ber 60. This adjusting mechanism consists of
positioning or locating operation of the work
70 a housing I90 secured to the end of sleeve I66.
piece I0.
_
The end of shaft I65 passes through said hous
An alternate arrangement shown in Figure 5
ing and has a threaded portion I9I thereon in
uses micro switches II‘I and H8 instead of the
engagement with a nut I92 rotatably mounted in
air-operated apparatus. Said switches may be
bearings I93. A worm wheel 200 on nut I92
connected directly to relays I I5 and H6.
Housing 66 must be mounted for movement 75 is engaged by worm gear20| mounted in the up
2,559,481
5
‘per part of housing I90. Said worm has a portion
80 is to the member 62, said members will spread
262 of polygonal cross-section so that a wrench
or crank may be applied thereto.
The means for engaging the work I0 is the
same as disclosed in the other ?gures except that.
instead of having means at one end to actuate
indicators, it is mounted in a member 2I0, form
until member 6| engages shoulder M and before
member 62 engages shoulder 80.
The spreading action will thus cause member
64 as a unit to move counterclockwise against
spring 86. Portion 92, when thus moved, shifts
feeler 95 to reduce the ?ow of air through valve
I00b so that pressure is built up in the manometer
ing a connection between said feeler 60 and the
tube I05, shifting the body of mercury therein
wheel shifting mechanism described above. Said
member 2I0 has a pair of spaced hollow cylin 10 to complete a circuit from II4 through contact
IIO, which is always submerged in the body of
drical portions 2“ and 2I2, one on either side of
mercury, through the mercury to the contact I I I,
bracket I61. The sleeve I66 passes through both
line II 3 to relay H6, which completes a circuit
of these portions and is secured therein by means
to motor I20 to rotate it in such a direction that
of set screws 2I3 and 2I'4. This mounting pro
vides a pivotal support for the work engaging 15 carriage 20 will be moved slightly to the right.
Movement to the left is effected in a similar
manner when the work is located off center to the
right. The work engaging member 62 engages
shoulder 80 instead of shoulder 8|, and the unit
Operation
20 in response to the action of pin ‘I0 moves to the
left or clockwise about pivot 65 so that extended
For the purpose of illustration, we have used
portion 92 engages feeler 96 to shift valve IIlIla
as a work piece, crank shaft I0 mounted on cen
to control the flow of air so as to raise the level
ters II and I2 for grinding main bearings I3, I4,
of the mercury in the contact portion of the tube
and I5. The locating device would work just as
well if said crank were mounted eccentrically for 25 I06. The rising column of mercury completes a
grinding the crankpins.
circuit between contacts H2 and I I I to energize
member 60 so that, when not in use, it may be
swung upwardly to inoperative position, sup
ported by sleeve I66.
Assuming that main bearing I3 has been
relay I I5. Said relay completes a circuit to motor
ground, the operator shifts lever 49 to the left
I20 ‘to rotate said motor in such a direction as to
to supply ?uid under pressure from line 46 to
move carriage 20 to the left until work engaging
line 43, and the plunger end of cylinder H to 30 member 60 has resumed its normal position and
shift piston 40 and plunger 39 downwardly
valve I00 returns to position to permit the mer
against spring 42. Plunger 39 is thus withdrawn
cury in tube I06 to drop away from contact III
from notch 38a. Lever 26 is shifted to the left
and stop motor I20 with the carriage 20 in the
and valve 25 to the right to connect line 3|
desired position.
through line 50 to the head end of cylinder 22. 35
In the meantime, feelers 6| and 62 have spread
As soon as carriage 20 begins to move, lever 49
to the point where feeler 62 is engaging shoulder
may be released and valve 44 will be moved to
80; and thus both feelers are in contact with the
the left by spring 48 to a, position to connect
respective shoulders. The movement of the car
line 43 with exhaust line 41. Spring 42 will
riage 20 to the right will shift the feeler unit so
then raise piston 40 and plunger 39 into engage 40 that the portion 92\will move away from feeler 95.
ment with spacing bar 35 so that, as soon as
The mercury in the tube I05 will drop away from
notch 38b moves into position, plunger 39 will
contact H0, and motor I20 will stop. The work
enter said notch and stop the carriage 20 in
piece I0 will then be in a position for the grinding
approximate position to grind bearing I4.
wheel I6 to engage both shoulders equally.
As soon as the carriage 20 stops, the operator 45
After the work engaging member 60 in Figure
may release lever 26, and valve 25 will be returned
6 has been moved into operative position, the
to neutral position by spring 52. A similar spring
feeler members GI and 62 are spread apart by
. 53 will move said valve to neutral position from
the action of spring ‘I5. If the position of the
the opposite direction.
axial work piece relative to the grinding wheel is
When carriage 20 comes to rest, the member 50 such that feeler member 6| engages shoulder 8|
60 is moved toward the work but is stopped at
as said work engaging member moves into posi
a point out of actual contact therewith. The
tion, then the spreading action will cause the
stop may be made by any suitable means provided
work engaging member 60 as well as the bracket
for this purpose. In actual practice, this move
2"), sleeve I66, shaft I65, bracket I62, and hence
ment would probably be effected automatically. 55 the grinding wheel I6, to move to the left. This
However, for the purpose of illustration, we show
movement will continue until feeler 62 engages
the locator mounted on resilient members I40
shoulder 80, thus stopping the spreading action
and “I so that the device may be moved into
‘and the movement to the left caused thereby.
and held in operative position manually. As
The size of the grinding wheel and the shoulders
soon as it has performed its function, it will be 60 80 and ill of the work piece are now in exact
returned to inoperative position by said members
I40 and HI.
As said locator is moved into operative posi
alignment, and the grinding wheel will grind
equally on both shoulders. As soon as the work
and wheel are centered, fluid under pressure can
tion, it engages the stem. I5I of valve I50 and
be directed either manually or automatically
moves said valve against the action of spring I52. 65 through line I85 to cylinder I80 in order to clamp
Said valve connects line ‘I6 with exhaust I53 to
the locating mechanism, and hence the grinding
release fluid from the forward end of piston 'II.
wheel, in the adjusted position.
Said piston is moved forward by means of spring
If, for any reason, the work engaging member
‘I5; and pin ‘I0, mounted in said piston, in re—
should get out of alignment with the grinding
sponse to said movement, spreads the members 70 wheel, adjustment may be effected by applying
U and 62 laterally in the direction of shoulders
a wrench or crank to the portion 202 of worm
00 and 8| on work piece I0. Assuming that the
gear 20I. Turning said worm gear will rotate
location of the carriage 20 by_plunger 39 and
nut I92 and cause shaft I65 to move endwise due
notch 38b has stopped in a position with shoulder
to the threaded portion I 9I in said nut. This
0| slightly closer to the member 6I than shoulder 75 will cause a relative axial movement between
2,559,481
ing wheel thereon, a locating device for position
ing said grinding wheel relative to spaced shoulders
‘work engaging member 60 and grinding wheel l6,
so that the two may be rotated to proper align- ,
on a work piece, comprising a work engaging unit
having scissorslike work engaging elements, means
for spreading said elements into engagement
1. In a machine tool, a work support, a tool
with said spaced shoulders, said elements being
support, means for effecting relative longitudinal pivotally mounted so that, if the work is of!
movement between said supports, a work locating
center, one of the work engaging members will
device for positioning a work piece having op
contact its corresponding shoulder before the
posed shoulder portions relative to said tool, com
prising a work engaging unit having scissorslike 10 other, connections between said work engaging
element and the portion of said wheel supporting
work engaging elements, means for spreading said
member adjacent said grinding wheel, said con
elements into engagement with said spaced shoul
necting means being I responsive ‘to continued
der portions, said elements being pivotally mount
spreading of said work engaging elements to move
ed so that, if the work is not in alignment with
the tool, one of the work engaging elements will 15 said grinding wheel into a predetermined posi
tion relative to said spaced shoulders.“
contact the corresponding shoulder before the
6. In a grinding machine for grinding spaced
other, said work engaging unit being rotatable
cylindrical portions of a work piece, each having
about said pivot in a direction away from the
opposed shoulder or ?anged portions, a grinding
shoulder in response to continued spreading of
said work engaging elements, and means respon 20 vwheel support, a grinding wheel rotatably mount
ed thereon, a work supporting means, means for
sive to the movement of said unit to set in opera
effecting relative axial movement between said
tion said longitudinal moving means for moving
work and said wheel to successively position said
the work in a direction to center said shoulder
cylindrical portions and said grinding wheel in
portions relative to said tool.
operative relation, includinga spacing bar for
ment.
We claim:
2. In a machine tool for machining spaced cy
25
lindrical portions of a work piece, each having
opposed shoulder portions, a work support, a tool
support, a cutting tool mounted thereon, means
one of said members having spaced notches cor
locating device to effect a precision adjustment ‘
shoulders on a work piece, comprising a work
responding to the portions to be ground, a plung
er for engaging said notches to position said
members in approximate operative relation, a
for effecting relative longitudinal movement be- '
work locating device having means for engaging
30
tween said supports ,to successively position said
said shoulder portions, and connections between
cylindrical portions and said cutting tool in op
said locating device and said wheel mounting at
erative relation, including a spacing bar for one
a point adjacent said wheel to effect a precision
of said supports having spaced notches corre
adjustment of said grinding wheel relative to said
sponding to the portions to be ground, a plunger
shoulder portions.
for engaging said notches to position said sup
7. In a grinding machine, means for rotatably
ports in approximate operative relation, a work ' supporting
a work piece, a grinding wheel sup
locating device having means for engaging said
port
and
means
for rotatably supporting a grind
shoulder portions, and means separate from said
ing wheel thereon, a locating device for posi~
longitudinal moving means and actuated by 'said
tioning said grinding wheel relative to spaced
between said member and said spacing bar,
whereby to place said tool and one of said por
tions of said work piece in substantially exact
alignment.
’
3. In a metal working machine, a device for
relatively locating a cutting tool and a work piece
having spaced shoulder portions, said device com
prising a scissorslike work engaging member hav
ing feelers for contacting said shoulder portions,
9. base for supporting said member, means for
spreading said feelers into engagement with said
shoulder portions including a piston, connections
between said piston and said feelers for actuating ,
same, means for urging said piston in a direction
to spread said work engaging members, and
means operable alternately with said last-named
means for urging said piston in the opposite di
engaging unit having scissorslike work engaging
elements normally in alignment with said grind
ing wheel, means for spreading said elements
into engagement with‘said spaced shoulders, said
elements being pivotally mounted so that, it the
work is not in alignment with the grinding wheel,
one of the work engaging members will contact
its corresponding shoulder before the other, con
nections between said work engaging element
and the portion of said wheel supporting mem
ber adjacent said grinding wheel, said connecting
means being responsive to continued spreading of
said work engaging elements to move said, grind
ing wheel into a predetermined position relative
to said spaced shoulders, and means for effecting
relative axial adjustment between said work en
gaging member and said grinding wheel.
8. In a grinding machine, a grinding wheel
4. In a metal working machine, a- device for 00 support, a work carriage, means for effecting rel
relatively locating a cutting tool and a work piece
ative longitudinal movement between said wheel
rection.
having spaced shoulder portions, comprising
support and said carriage, a work locating device
scissorslike work engaging feelers, a base for sup
for effecting a relative positioning movement be
porting said feelers, means for spreading said
tween spaced ‘shoulders on work pieces and a
feelers into engagement with said shoulder por 65 grinding wheel, comprising a work engaging unit
tions, including a piston, connections between
having scissorslike work engaging elements,
said piston and said feelers for actuating same,
means for spreading said elements into engage-_
means for urging said piston in a direction to
ment with said spaced shoulders, said elements
spread said feelers, means forvholding said piston
being pivotally mounted so that, if the work is
in inoperative position, and means operable upon 70 not in alignment with the grinding wheel, one of
_ movement of said locating device into operative
the work engaging elements will contact the cor
position for releasing said holding means.
responding shoulder before the other, and means
5. In a grinding machine, means for rotatably
responsive to continued spreading of said work
supporting the work piece, a grinding wheel sup
engaging elements to initiate said relative lon
‘
port and means for rotatably supporting a grind— 75
gitudinal movement to place the grinding wheel
2,559,431
10
and spaced shoulders on the work piece in align
ment.
9. In a grinding machine, a work support, a
grinding wheel rotatably mounted thereon, a
grinding wheel support, means for effecting rela
tive axial movement between said supports, a
work locating device for positioning work pieces
having opposed shoulder portions relative to a
means being effective to stop said relative axial
movement when said predetermined position is
reached.
MILBURN A. HOLLENGREEN.
DONALD F. PRICE.
REFERENCES CITED
The following references are of record in the
grinding wheel, comprising a scissorslike work . 0 ?le of this patent:
engaging member positioned in operative rela l
UNITED STATES PATENTS
tion to said shoulder portions, and means actuat
Number
Name
Date
ed by said work engaging member when said
1,640,993
Hanson __________ __ Aug. 30, 1927
shoulder portions are out of alignment with said
1,840,231
Harrison et al. _____ Jan. 5, 1932
grinding wheel to initiate said relative axial
Ott et a1. ________ __ Nov. 5. 1940
movement between said work and said wheel to 15 2,220,490
Flygare et a1 ______ __ Nov. 25, 1941
2,264,160
place said parts in a predetermined position, said