U.S. patent number 3,670,456 [Application Number 05/107,034] was granted by the patent office on 1972-06-20 for honing tool arrangements.
This patent grant is currently assigned to Hi-Ton Machine Tools Limited. Invention is credited to Anthony James Harratt.
United States Patent |
3,670,456 |
Harratt |
June 20, 1972 |
HONING TOOL ARRANGEMENTS
Abstract
A honing tool arrangement which includes a tubular shaft to one
end of which can be attached a honing tool and the tubular shaft
and the honing tool are capable of being reciprocated and rotated,
a control rod in the tubular shaft and associated with a piston and
cylinder device to cause fast feed longitudinal movement of the
control rod relatively to the tubular shaft to cause fast increase
and decrease of the effective cutting diameter of the honing tool
and disengageable screw means between the tubular shaft and the
control rod and rotational brake means associated with the control
rod and capable of "braking" the rotation of the control rod
relative to the tubular shaft when the screw means is engaged to
cause slow feed longitudinal movement of the control rod relative
to the tubular shaft and thus to cause a slow increase and decrease
of the effective cutting diameter of the honing tool.
Inventors: |
Harratt; Anthony James
(Werrington, EN) |
Assignee: |
Hi-Ton Machine Tools Limited
(Selly Oak, Birmingham, EN)
|
Family
ID: |
22314507 |
Appl.
No.: |
05/107,034 |
Filed: |
January 18, 1971 |
Current U.S.
Class: |
451/151; 451/14;
451/472 |
Current CPC
Class: |
B24B
33/105 (20130101) |
Current International
Class: |
B24B
33/00 (20060101); B24B 33/10 (20060101); B24b
007/00 () |
Field of
Search: |
;51/34R,34C,34D,34J,165.77,165.8,346,338,339,340,344,341,343 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Armstrong; William R.
Claims
I claim:
1. A honing tool arrangement of the kind comprising a tubular shaft
means capable of being rotated about its longitudinal axis and
reciprocated axially and of having attached thereto the honing tool
to be rotated and reciprocated therewith and also including a
honing tool diameter control means including a control rod in the
tubular shaft means and capable of being moved longitudinally
relatively to the tubular shaft means to increase and decrease the
effective cutting diameter of the honing tool said control means
also including fast and slow feed means to cause fast and slow
changes respectively in the effective cutting diameter of the
honing tool and said slow feed means including screw means wherein
the improvements provided are a screw member (136) on the control
rod (104, 126, 134) and a complementary nut member (138) carried by
the tubular shaft means (46, 48, 52) so as to be movable
rotationally and longitudinally therewith, said nut member (138)
being movable into a disengaged position with the screw means (136)
to permit fast feed longitudinal movement of the control rod (104,
126, 134) and being movable into an engaged position with the screw
member (136), and rotational brake means (84) associated with the
screw means (136, 138) and operative to cause relative rotation of
the engaged screw member (136) and nut member (138) while the
tubular shaft means (46, 48, 52) is rotating to cause slow feed
longitudinal movement of the control rod (104, 126, 134).
2. A honing tool arrangement according to claim 1 wherein the
improvement provided is that the brake means (84) is adjustable to
vary the braking, that is the "drag" effect, and thus to vary the
rate of slow feed longitudinal movement of the control rod (104,
126, 134).
3. A honing tool arrangement according to claim 2 wherein the
improvement provided is that the brake means (84) is a liquid brake
means relying upon the drag effect created by a viscous liquid in
contact with relatively rotatable brake elements (86, 88).
4. A honing tool arrangement according to claim 3 wherein the
improvements provided are that the liquid brake means (84)
comprises a non-rotatable element (86) and a rotatable element (88)
which latter is connected to the control rod (104, 126, 134) in
such a manner as to be rotatable therewith.
5. A honing tool arrangement according to claim 1 wherein the
improvements provided are that the nut member (138) of the screw
means is mounted so as to be radially movable in the tubular shaft
means (46, 48, 52) and has inclined plane engagement (140, 142,
144, 146) with a nut moving member (148).
6. A honing tool arrangement according to claim 5 wherein the
improvements provided are that the nut moving member (148) is
associated with a fluid-pressure operated piston and cylinder
device (152, 154) so as to be moved thereby to cause radial
movement of the nut members (138).
7. A honing tool arrangement according to claim 1 wherein the
improvement provided is that the screw means (136, 138) is disposed
at or adjacent that end of the tubular shaft means (46, 48, 52) at
which the honing tool (28) may be positioned to avoid variations
occurring in the effective diameter of the honing tool (28) due to
the honing tool arrangement being generally alternatively in
compression and tension during forward and return movements
respectively of said arrangement in the bore of the workpiece tube
being honed.
8. A honing tool arrangement according to claim 1 wherein the
improvement provided is that the screw means (136, 138) is disposed
in the honing tool (28) itself to avoid variations occurring in the
effective diameter of the honing tool (28) due to the honing tool
arrangement being generally alternatively in compression and
tension during forward and return movements respectively of said
arrangement in the bore of the workpiece tube being honed.
9. A honing tool arrangement according to claim 1 wherein the
improvement provided is that fast feed control means comprises a
fluid-pressure piston and cylinder device (110,112).
10. A honing tool arrangement according to claim 9 wherein the
improvements provided are that the fast feed control means
comprises a plurality of fluid-pressure piston and cylinder devices
(110,112) disposed offset from the longitudinal axis of the
apparatus, said devices being non-rotatable about the longitudinal
axis of the apparatus and associated with the control rod (104,
126, 134) so as to permit rotation thereof.
11. A honing tool arrangement according to claim 1 wherein the
improvement provided is that the screw means (136) is associated
with the rotational brake means (84) through a disengageable
coupling (94) so that when said coupling is disengaged the brake
means (84) is rendered ineffective and cannot alter the effective
diameter of the honing tool (28) so that said honing tool can
perform a "dwell stroke" honing action to improve the accuracy of
the bore in the workpiece tube being honed.
12. A honing tool arrangement according to claim 11 wherein the
improvement provided is that the disengageable coupling (94) is a
friction clutch coupling.
13. A honing tool arrangement according to claim 12 wherein the
improvement provided is that the friction clutch coupling is an
electro-magnetically operated coupling (94).
14. A honing machine wherein the improvement provided is that a
honing tool arrangement according to claim 1 is incorporated in the
machine.
Description
SUMMARY OF THE INVENTION
According to the present invention there is provided a honing tool
arrangement of the kind comprising a tubular shaft means capable of
being rotated about its longitudinal axis and reciprocated axially
and of having attached thereto the honing tool to be rotated and
reciprocated therewith and also including a honing tool diameter
control means including a control rod in the tubular shaft means
and capable of being moved longitudinally relatively to the tubular
shaft means to increase and decrease the effective cutting diameter
of the honing tool said control means also including fast and slow
feed means to cause fast and slow changes respectively in the
effective cutting diameter of the honing tool and said slow feed
means including screw means wherein the improvements provided are a
screw member on the control rod and a complementary nut member
carried by the tubular shaft means so as to be movable rotationally
and longitudinally therewith, said nut member being movable into a
disengaged position with the screw means to permit fast feed
longitudinal movement of the control rod and being movable into an
engaged position with the screw member, and rotational brake means
associated with the screw means and operative to cause relative
rotation of the engaged screw member and nut member whilst the
tubular shaft means is rotating to cause slow feed longitudinal
movement of the control rod.
BRIEF DESCRIPTION OF THE DRAWINGS.
The invention will now be more particularly described by way of
example with reference to the accompanying drawings in which:
FIG. 1 is a diagrammatic perspective view, with a part cut away for
clarity, of a honing machine constructed in accordance with the
present invention,
FIGS. 2, 3 and 4 are vertical sectional views of a honing tool
arrangement and the views are continuations of the lower part of
the preceding view,
FIG. 5 is a cross-sectional view of FIG. 4 on the lines 5--5
thereof and on an enlarged scale, and,
FIG. 6 is a view corresponding to a part of FIG. 4 but showing a
modification.
For convenience similar reference numerals will be used to denote
corresponding parts with regard to FIGS. 1 to 5 and FIG. 6.
Referring to FIG. 1, this illustrates a vertical honing machine
having two identical honing tool arrangements 10 and 12 mounted in
a horizontal overarm 14 disposed at the top of a pillar 16
extending upwardly from a bed 18 upon which two workpiece tubes
(not shown) to be honed can be supported in jigs or fixtures so
that the two workpiece tubes can be honed simultaneously. It should
be appreciated that whilst the honing tool arrangement will be
described as applied to the vertical honing machine, the invention
is equally applicable to a horizontal honing machine.
As the two honing tool arrangements 10 and 12 are identical one
only will be described as representative of both.
The honing tool arrangement comprises an upper or head assembly 20
which extends from the upper end of the view shown in FIG. 2 to a
disconnectable bayonet joint 22 indicated in FIG. 3 at which can be
disconnectably connected a lower or connecting assembly 24 also
shown in FIG. 4 and to the lower end of which can be disconnectably
connected, by a bayonet joint 26, a honing tool 28. The honing tool
28 is of generally conventional construction comprising a tubular
body 30 formed at its upper end with a spigot 32 carrying the
radial bayonet joint pegs 34 adapted to engage bayonet-type slots
in the lower end of the connecting assembly 24 to enable the honing
tool 28 to be detachably connected to said assembly 24. Mounted
within the body 30 is a push-rod 36 which is spring-urged upwardly
by a helical compression spring 38 and is formed with two
downwardly convergent frusto-conical cams 40 which bear on
complementary shaped carriers 42 for honing stones 44, only one of
which is shown, so that longitudinal downward movement of the
push-rod 36 causes expansion of the effective honing diameter of
the honing tool 28.
The head assembly 20 includes a tubular shaft portion 46 and the
connecting assembly 24 comprises a tubular shaft portion 48
connected by a universal joint 50 to a tubular shaft portion 52
which is provided at its lower end with the bayonet joint slots for
the bayonet joint pins 34.
The tubular shafts 46, 48 and 52 form a tubular shaft means which
is rotatable about the vertical longitudinal axis X--X and for
which purpose the tubular shaft portion 46 is externally splined to
receive a splined toothed bevel wheel 54 which meshes with a
driving toothed bevel wheel 56 secured to a shaft 58, see FIG. 1,
of an electric motor 60 and the two bevel wheels are housed in a
box 62 whereby a fixed ratio gearbox is provided and this gearbox
is secured to the stationary overarm 14. In this way when the motor
60 is operated the honing tool 28 is rotated about the axis
X--X.
In order to reciprocate the honing tool 28 longitudinally of the
axis X--X and thus vertically the tubular shaft portion 46 is
anti-fricationally mounted by both radial and thrust bearings
indicated generally at 64 in a cross-head 66 provided with bushes
68 which can slide vertically along vertical guide rods 70 secured
to and extending downwardly from the overarm 14 and supported at
their lower ends in brackets 71 of the pillar 16 and secured to the
cross-head 66 are piston rods 72 of fluid-pressure operated piston
and cylinder devices 74 of which the cylinders are secured to the
overarm 14. Thus, when the devices are extended and contracted the
cross-head 66 and thus the honing tool 28 are moved downwardly and
upwardly respectively relative to the stationary workpiece tube
being honed.
Secured to the stationary gearbox 62 are two vertical guide posts
75 connected at their upper ends by a cross-bar 76 and the upper
end of the tubular shaft portion 46 is mounted in anti-friction
bearings 78 in a slide 80 mounted on the guide posts 75.
Rigidly supported by the slide 80 is a body 82 composed of a
plurality of parts rigidly secured together so as to be
reciprocable with the slide 80 and mounted at the upper end of the
body is a rotational brake means 84. The brake means 84 is a
rotational liquid brake means of a kind sold under the trade mark
"Kinetrol" as a rotary dash-pot and comprises a non-rotatable brake
element 86 and a rotatable brake element 88 and between the
elements and in contact therewith is a viscous liquid which is
capable of exerting a braking or "drag" effect on the rotatable
element and this braking or drag effect is adjustable by adjustment
means comprising a manually rotatable adjustable nut 90 which has
screw-threaded engagement with a plunger 92 to which the
non-rotatable brake element 86 is secured so that manual rotation
of the nut 90 results in moving the non-rotatable brake element 86
nearer to or farther away from the rotatable brake element 88
whereby the drag effect can be increased and decreased
respectively.
The rotatable brake element 88 is secured to a spindle 91 mounted
in anti-friction bearings and is connected to a friction plate 93
of an electro-magnetic clutch 94, which forms a disengageable
coupling, and which also comprises a further friction plate 96
secured to a spindle 98 mounted in anti-friction bearings and at
the lower end of which spindle is formed a squared spigot 100 which
is in permanent axial sliding engagement with a squared socket 102
formed in the upper end of an upper portion 104 of a control rod
and said spigot 100 is relatively long to permit sufficient
longitudinal movement of the socket 102 for performing a fast
expansion and contraction of the honing tool 28 as will hereinafter
be described.
The electro-magnetic clutch 94 is arranged to be controlled either
manually or automatically such as by a timing device or a bore
sizing or gauging device so that the two friction plates of said
clutch can be disengaged and frictionally engaged with each other
as required.
The upper portion 104 of the control rod is provided with a flange
106 on which is mounted, through anti-friction thrust bearings, an
annular thrust plate 108 so that the upper portion 104 of the
control rod and the annular thrust plate 108 move together
longitudinally of the axis X--X while, however, said upper portion
of the control rod 104 can rotate relatively to the annular thrust
plate 108.
Abutting the upper side of the thrust plate 108 are the lower ends
of a plurality, for example three, equiangularly spaced apart
pistons 110 of fluid-pressure operated piston and cylinder devices
also comprising complementary cylinders 112 formed in the body 82
and said devices are offset from the longitudinal axis X--X and are
double-acting and are supplied with hydraulic fluid-pressure
through ports 114 and 116. The annular thrust plate 108 is secured
to the three pistons by screws 118 so that the upper portion 104 of
the control rod is positively moved by the pistons 110
longitudinally of the axis X--X and said piston and cylinder
devices 110 and 112 constitute a fast control means such that when
the pistons 110 are urged downwardly by hydraulic pressure the
control rod causes a fast expansion of the effective diameter of
the honing tool 28 or can permit a fast contraction thereof.
The lower end of the upper portion 104 of the control rod is formed
with a blink squared socket 120 with which is engaged so as to abut
the end of the socket a squared spigot 122 in the vicinity of a
universal joint 124 between the upper and lower portions 46 and 48
of the tubular shaft. The spigot 122 is formed at the upper end of
an intermediate portion 126 of the control rod which is
spring-urged upwardly by a helical compression spring 128 so that
engagement of the spigot 122 with the blind socket 120 is
maintained. The lower end of the intermediate portion 126 of the
control rod is formed with a blind squared socket 130 which is
engaged by a squared spigot 132 at the upper end of a lower portion
134 of the control rod which is urged upwardly by the spring 38 and
push-rod 36 so that the spigot abuts the blind end of the squared
socket 130.
Disposed in the lower assembly 26 and in the tubular shaft portion
52 thereof is a screw means for effecting a slow and thus powerful
feed to increase the effective cutting diameter of the honing tool
28 and this screw means comprises a lead screw 136 formed on the
lower control rod portion 134 and a pair of opposite nut members
138 of which both are shown in FIG. 5 but one only is shown in FIG.
4 for convenience and these nut members are rectilineally slidably
mounted in the tubular shaft portion 52 so as to be radially
movable inwardly into engagement with the lead screw 138 and
outwardly out of engagement with said lead screw whilst, however,
said nut members 138 are supported so as not to be movable axially,
i.e. longitudinally relatively to the tubular shaft portion 52 and
thus of the axis X--X.
Each nut member 138 is formed with an inclined plane 140 and a peg
142 which are co-operative respectively with inclined planes 144
and 146 of a nut moving member 148 which is slidably supported by
the tubular shaft portion 52 so as to be slidable longitudinally
parallel with the axis X--X but being prevented from transverse
movement.
The upper end of the two nut moving members 148 are each secured by
a screw 150 to an annular piston 152 mounted within a cylinder 154
and the upper end of the cylinder is supplied by pneumatic pressure
through a passage 156 and a flexible pipe 158 which in turn
communicates with passages in the cross-head 66, these passages
being indicated 160, 162, 164 and 166 which communicates with a
port 168 which can be connected in any suitable manner by a
flexible pipe with a source of pneumatic pressure, not shown. Thus,
when pneumatic pressure is supplied to the upper end of the
cylinder 154 the annular piston 152 is urged downwardly to cause
the two nut members 138 to move radially inwardly into engagement
with the lead screw member 136 whereas when the pneumatic pressure
is discharged or released from the cylinder 154 the annular piston
152 is urged upwardly by six helical compression springs 158
operating between the underside of the annular piston 152 and the
location bores in the tubular shaft member 52 whereby the two nut
moving members 148 are moved upwardly and operate on the pegs 142
so as positively to move the nut members 138 out of engagement with
the lead screw 136. The screw means comprising the lead screw 136
and the nut members 138 comprise a slow feed means to enable slow
but powerful and substantially positive expansion of the effective
diameter of the honing tool 28 to be caused.
In operation to effect a honing operation in a workpiece tube, the
pistons 112 of the fast feed means are considered to be in their
upper positions as shown in FIG. 2 and the nut members 138 are out
of engagement with the lead screw 136 so that the honing tool 28 is
fully contracted by the conventional spring rings or gaiters 170
which draw the stone carriers 42 radially inwardly and the
contracted honing tool is moved downwardly into the bore of the
workpiece tube by extension of the devices 74. The electric motor
60 is then started to rotate the tubular shaft means 46, 48 and 52
through the fixed ratio gearbox 62 and continued extension and
retraction of the devices 74 causes reciprocation of the honing
tool 28 longitudinally thereof in the workpiece bore. The fast feed
means comprising the piston and cylinder devices 110 and 112 are
then operated by introducing hydraulic pressure into the passage
114 whereby the control rod comprising the portions 104, 126 and
134 is urged longitudinally downwardly to urge the push-rod 36
downwardly and cause rapid expansion of the honing tool 28 whereby
the honing stones 44 bear on the bore wall of the workpiece
tube.
To cause a slow but substantially positive and powerful feed and
expansion of the honing tool 28 pneumatic pressure is introduced
through the port 168 in the cross-head 66 and into the cylinder 154
to urge the annular piston 152 downwardly whereby the nut moving
members 148 are urged downwardly and the nut members 138 are urged
radially inwardly by the inclined plane action between the inclined
planes 144 and 140 so that the nut members engage the lead screw
136. Providing the electro-magnetic clutch 94 is open, i.e. the
friction plates 93 and 96 are not engaged with each other, the lead
screw 136 and the control rod portions 126 and 104 are merely
rotated with the tubular shaft means at the same speed thereof but
when the electro-magnetic clutch is operated so that the two
friction plates 93 and 96 thereof are frictionally engaged with
each other the rotatable element 88 of the rotational brake means
84 also tends to be rotated but is "braked" by the drag effect
created by the rotational brake means and the hand of the lead
screw 136 is such, in relation to the direction of rotation of the
tubular shaft means 46, 48 and 52 that the lead screw and thus the
control rod portion 134 and the push-rod 36 are forced
longitudinally downwardly to cause further and substantially
positive expansion of the effective diameter of the honing tool 28.
Thus the slow feed or expansion of the honing tool 28 during the
honing action is caused as a result of the brake action imposed by
the rotational brake means 84 and the braking torque can be
adjusted either before or during a honing operation by manually
adjusting the control knob 90 of the rotational brake means 84.
The honing operation then proceeds with expansion of the honing
tool 28 in either of a number of ways. For example, the nut members
138 may be caused to be disengaged from the lead screw 136
automatically by a sizing device which gauges the size of the bore
in the workpiece or instead of the disengagement being effected by
the sizing device, the disengagement may be effected by means of a
timing or a stroke counting device by which the number of
reciprocations of the honing tool are counted. When the nut members
138 are disengaged from the lead screw 136 the honing tool 28 is
contracted by the gaiters 170 as a result of the compression
springs 38 and 128 urging the control rod vertically upwardly.
Alternatively when the sizing device or the timing or stroke
counting devices have operated and the bore of the workpiece tube
is substantially finished, the rotational brake means is disengaged
but the nut members 138 remain engaged with the lead screw 136 and
the honing tool 28 continues to be reciprocated and rotated thus
allowing a dwell stroke honing action to be continued for a
predetermined time by a stroke counting device to improve the
accuracy of the bore in the workpiece tube.
In a still further alternative mode of operation the disengageable
coupling 94 is caused to be momentarily engaged and disengaged at
predetermined points of the reciprocation cycle of the honing tool
whilst the nut members 138 are engaged with the lead screw 136, so
that an incremental expansion of the honing tool is obtained as an
alternative to the steady continuous expansion obtained when the
disengageable coupling 94 remains continuously engaged.
In order to remove the honing tool 28 from the bore of the
workpiece tube which is being honed, the pneumatic pressure is
exhausted from the upper end of the cylinder 154 to permit the
springs 158 to urge the piston 152 upwardly and thus also to urge
the nut moving members 148 upwardly whereby the nut members 138 are
positively moved radially outwardly and out of engagement with the
lead screw 136 by the inclined plane actions developed between the
pins 142 and the inclined planes 146 and hydraulic pressure is
exhausted from the upper ends of the three cylinders 112 through
the ports 114 and is admitted to the lower ends of said cylinders
through the ports 116 whereby the annular thrust plate 108 is
lifted with the assistance of the springs 128 and 38 which latter
also lifts the push-rod 36 to enable the honing tool 28 to be
contracted by the gaiters 170. The devices 74 are then
contracted.
It should be appreciated that as the slow feed means comprising the
lead screw 136 and nut members 138 is disposed at or adjacent that
end of the tubular shaft at which the honing tool 28 is positioned,
the subjection of the tubular shaft and control rod to compression
and tension during forward and return movements respectively of
said arrangement whilst reciprocating in the bore of the workpiece
tube being honed does not cause variations in the effective
diameter of the honing tool 28 which is of standard design. In
order to obtain the same beneficial effects of avoidance of
variations in the effective diameter of the honing tool a special
or non-standard honing tool 28 may be provided as shown in FIG. 6
in which the lead screw 136 is provided on the push-rod 36 of the
honing tool and the nut members 138 are slidably mounted in the
body 30 or a tubular shaft part 170 permanently secured to the body
30 but otherwise the construction is similar to that illustrated in
FIGS. 1 to 5.
It should be appreciated that the honing tool diameter control
means herein referred to comprises the control rod composed of the
three portions 104, 126 and 134 in FIGS. 1 to 5 and the control rod
composed of the three portions 104, 126 and 36 in FIG. 6, the fast
feed means comprising the piston and cylinder devices 110 and 112
and the slow feed means comprising the lead screw 136 and the nut
members 138.
When a honing tool arrangement as described above has been set up
in a honing machine in which a workpiece tube has been loaded, the
various operations are performed in proper sequence either
automatically or under manual control or a combination of both.
While the nut members 138 are mounted so as to be rectilineally
slidable radially with regard to the lead screw 136 and are movable
by inclined plane actions, alternatively said nut members may be
pivotally mounted about axes parallel with the axis of the lead
screw or transverse to said axis but so as, however, during the
actual engagement and disengagement of the nut members with or from
the lead screw, also to move in a substantially radial manner and
said pivoted nut members may be operated other than by inclined
plane actions such as for example lever means operated by the
annular piston 152.
The invention thus provides a honing tool arrangement of the kind
specified which is more efficient than known honing tool
arrangements.
* * * * *