Information
-
Patent Grant
-
6647869
-
Patent Number
6,647,869
-
Date Filed
Tuesday, April 2, 200222 years ago
-
Date Issued
Tuesday, November 18, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Ostrager; Allen
- Nguyen; Jimmy
Agents
-
CPC
-
US Classifications
Field of Search
US
- 100 257
- 100 282
- 100 283
- 100 285
- 100 286
- 100 280
- 072 441
- 072 450
- 072 451
- 072 452
- 074 571 L
- 074 602
- 074 603
- 074 600
- 074 595
- 083 628
- 083 530
-
International Classifications
- B30B500
- B30B106
- F16C304
- B21J746
-
Abstract
A positive lock for infinite adjustable stroke alignment mechanism for a mechanical press with an eccentric bushing disposed within a press connection member with a second eccentric member disposed within the eccentric bushing. A rotatable crankshaft is connected to the second eccentric member. A positive lock alignment mechanism is included for aligning the press connection member with the eccentric bushing to prevent rotation therebetween and permitting rotation of the second eccentric member with the eccentric bushing for infinite stroke adjustment whereby rotation of the crankshaft, when the mechanism is activated causes a press stroke adjustment.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a mechanical stamping and drawing presses, and, more particularly, to an apparatus for a positive lock for infinite adjustable stroke connection for adjusting the stroke length.
2. Description of the Related Art
In mechanical presses, it is often desirable to adjust or change the stroke length of a reciprocating member, for example the slide, to which a stamping tool is installed. In some prior art tooth adjustment systems, there is a tendency of the system parts to wear after a certain period of operation time. It would be desirable to provide an apparatus or system which may be utilized to quickly, easily and accurately adjust the stroke length of a slide or other parts while ensuring alignment of the stroke connection system. In addition, in some mechanical presses with an indefinite adjustable stroke mechanism, there will be a small amount of slippage from one connection to a second connection on a press with the connections and eccentric on a crankshaft after hundreds of stroke changes. Thus, if one of the eccentric bushings rotates a percentage of degree in relation to the secondary eccentric on the crankshaft during the stroke adjustment process, this will cause the stroke mechanism to be out of adjustment.
SUMMARY OF THE INVENTION
The present invention provides an alignment connection for use in a dual eccentric adjustable stroke connection system for use in changing the stroke length of the slide or other member of the mechanical press such as described in U.S. Pat. No. 5,865,070.
An eccentric on a rotatable crankshaft is supplied within an eccentric bushing disposed thereon. A press connection member, such as a connecting rod or link, is attached about the eccentric bushing. During normal operations, there is a relative movement between the eccentric bushing and the connecting member arm to thereby cause reciprocation of the press slide. During stroke adjustment, pressure oil is communicated between the eccentric bushing and the crankshaft eccentric, thereby relieving the press fit or interference fit there between, and causing the eccentric bushing to expand and form a temporary press fit connection with the connecting arm. At this time, the crankshaft may be rotated, along with its eccentric, to thereby change the position of the eccentric within the eccentric bushing. This causes a change of the stroke length. The oil pressure is then relieved thereby causing the eccentric bushing to contract and again form a press fit with the crankshaft eccentric and release the temporary press fit connection between the outside of the eccentric bushing and the connection member arm. After such oil pressure has been reduced, normal press operations may proceed. During normal operations and repeated press operations and stroke adjustments, there can be slippage between the larger eccentric bushing and the connection arm after repeated stroke changes. Thus, if one of the eccentric bushings rotates a percentages of a degree in relation to the secondary eccentric on the crankshaft during the stroke adjustment process, this will cause the slide parallelism from the bottom of the slide to the top of the bolster on the bed to be out of specification. The addition of the positive lock for infinite adjustable stroke and alignment mechanism ensures that during the stroke adjustment process, no movement or slippage will occur and the stroke adjustment will be made uniformly and accurately during each stroke adjustment.
The invention comprises, in one form thereof, a mechanical press having a press connection member, an eccentric bushing disposed within the press connection member, and a second eccentric member disposed within the eccentric bushing. The second eccentric member releasably connectable within the eccentric bushing. A rotatable crankshaft is connected to the second eccentric member. The invention includes a system for connecting the eccentric bushing with the press connection member to prevent rotation there between and permitting rotation of a second eccentric member within the eccentric bushing whereby rotation of the crankshaft, when the system is activated, causes a press stroke adjustment. The invention also includes an alignment connection means that secures the press connection member or multiple press connection members to the eccentric bushings at a predetermined position that ensures the proper positioning of each and every eccentric within the adjustable stroke bushing.
The invention comprises, in another form thereof, a double acting cylinder means for activating the alignment means, such as a U-bar, into and out of the key ways provided for proper alignment of the eccentric bushing and the press connecting members. The alignment means includes a spring to hold the U-bar open so that the U-bar and the eccentric bushing never come in contact and causes a collision when the eccentric bushing is rotating and fixed to the crankshaft.
An advantage of the present invention is that the mechanical presses may now include a positive lock for infinite adjustable stroke alignment mechanism to ensure simple and compact stroke adjustment connections operated by fluid pressure. This is an improvement over prior stock adjustment connections that utilize keys and/or gearing between the crankshaft and the various eccentrics and ensures no slippage or movement of the larger eccentric and connection arms during stroke adjustment operated by fluid pressure.
Another advantage of the present invention is that mechanical presses with infinite adjustable stroke mechanisms will have a small amount of slippage from one connector to the other connector on a press with multiple connection members and their respective eccentric bushings on a crankshaft after hundreds of stroke changes. The present invention will prevent rotational movement of the eccentric bushing in relation to the secondary eccentric on the crankshaft and the bearing cap not to move out of specification, during the time the press stroke is being adjusted.
Another advantage of the present invention is that the alignment mechanism can be used with the simple and compact stroke adjustment connection operated by fluid pressure. The present invention utilizes a connection that is simple in design and vastly reduces the number of parts necessary for a stroke adjustment mechanism and a method to ensure proper alignment.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1
is a schematic, prospective view in a partial cut away of a portion of the crankshaft and slide connection;
FIG. 2
is a cross-sectional view along line E—E of
FIG. 1
of the cylinder support and alignment bar;
FIGS. 3
a
and
3
b
are cross-sectional views along the line H—H of FIG.
1
and along the line F—F of
FIG. 3
a
respectively, along the crankshaft axis at several times of operation, namely during normal stamping operations and during stroke length/eccentric adjustment;
FIG. 4
is an axial, cross-sectional view of the press mechanisms showing the crankshaft and connections along with the cylinder support for the alignment mechanisms; and
FIG. 5
is an elevational view of a typical mechanical press utilizing the present invention.
Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent embodiments of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated or omitted in order to better illustrate and explain the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The positive lock for the infinite adjustable stroke mechanism of the present invention is ideally suited for a wide assortment of configurations of mechanical and stamping presses utilizing one or more connections. As is conventional, a mechanical press
110
(wherein
FIG. 5
) typically includes a crown portion
115
, a bed portion
117
having a booster assembly connected thereto, and uprights
113
connecting crown portion
115
with the bed portion
117
. Uprights
113
are connected to or integral with the underside of crown portion
115
and the upper side bed portion
117
. A slide
119
is positioned between uprights
113
for a guided, reciprocating movement relative to bed portion
117
. Tie rods (not shown), which extend through crown portion
115
, uprights
113
and bed portion
117
, are attached with each end with the tie rod nuts. Leg members
118
are formed as an extension of the bed and are generally mounted on the shop floor by means of shock absorbing pads.
In order to power the reciprocating motion of slide
119
, a drive mechanism
114
for the press is provided. The drive mechanism
114
includes a motor
116
, a clutch
130
, a press drive shaft
131
and a flywheel
120
. The press driveshaft
131
is connected to a pinion
132
which rotates crankshaft
14
. A flywheel
120
is connected to a main flywheel
133
which in turns selectively engages the clutch of the combination clutch brake to power rotation of the press crankshaft
14
, which in turn effects slide motion via connections extending between the slide and the crankshaft. This description of press
110
and its drive mechanism is merely illustrative. A wide variety of mechanical presses are well known in the art, and the use of the present invention can be utilized with any mechanical press that utilizes a crankshaft type device to achieve reciprocating motion of a press component. An example of a mechanical press is disclosed in U.S. Pat. No. 5,189,928 entitled “Adjustable Stroke Punch Press”, which is incorporated herein by reference.
Referring to
FIG. 1
, there is schematically shown a cross-sectional view of a crankshaft main portion
16
, its associated eccentric bushing
20
and connection
10
which is powered by the crankshaft rotation. The connection may be formed of a bottom portion and a cap, and the bottom portion of connection member
10
is attached in a suitable fashion to the press slide. The crankshaft
14
includes a cylindrical main portion
16
axially centered on the crankshaft axis of rotation and a second eccentric member such as a cylindrical eccentric
18
, rotatably fixed thereto or integrally formed therewith. Although only one crankshaft eccentric is shown, multiple eccentrics and connection members
10
would be provided along the axial length of the crankshaft to cooperate with additional connectors which are not shown. Ringing crankshaft eccentric
18
is an eccentric bushing with a keyway
22
to receive an alignment bar
30
to ensure proper alignment during press stroke adjustment.
FIG. 2
is a cross-sectional view of cylindrical support
40
and alignment bar
30
.
FIGS. 3
a
and
3
b
illustrate the configuration of the alignment mechanism in the position for production and the position during stroke change. In
FIG. 3
a
, alignment bar
30
is in the upright position and is not engaging eccentric bushing
20
or crankshaft
14
. This allows crankshaft
14
and eccentric bushing
20
to rotate freely during production without a collision. In
FIG. 3
b
, alignment bar
30
is shown lowered into eccentric bushing
20
for positive lock position during stroke change.
FIGS. 1 and 4
better illustrate the configuration of these components, wherein the crankshaft main portion
16
is shown with crankshaft eccentric
18
and eccentric bushing
20
as these components would appear during normal press operation. Alignment bar
30
is now removed or in the up position and removed from keyway
22
as it would be positioned or appear during normal stamping operation. A double acting cylinder
28
and a spring
26
(shown in
FIG. 4
) to hold alignment bar
30
in the upward position so eccentric bushing
20
is affixed to the crankshaft and rotates with the crankshaft and alignment
30
, and never communicates into keyway
22
and thus cause a collision with the rotating crankshaft. Found on the sides of keyway
22
are two sensors
24
that detect whether alignment bar
30
is in the up position or the down position through the use of upper limit switch
34
which indicates alignment bar
30
is up, and lower limit switch
32
which indicates that alignment bar
30
is down and engaging eccentric bushing
20
, as shown in
FIG. 3
a
. Not shown in the figures is a keyway on both sides of connection member
10
. Alignment bar
30
can be a U-shaped bar to engage a similar keyway on the opposite of connection member
10
.
FIG. 3
a
depicts the invention with alignment bar
30
lowered into keyway
22
and engaged within eccentric bushing
20
for press stroke adjustment by hydraulic oil pressure as described in U.S. No. Pat. 5,865,070 entitled “Adjustable Stroke Connection”. As depicted in
FIG. 3
a
, alignment bar
30
has been lowered into keyway
22
by double acting cylinder
28
, shown in
FIGS. 1 and 4
, so as to affix alignment bar
30
into eccentric bushing
20
to make stroke adjustments. The mechanical press is stopped and crankshaft eccentric
18
and eccentric bushing
20
are aligned on top with keyway
22
in alignment with alignment bar
30
. A double acting cylinder
28
pushes alignment bar
30
into keyway
22
of eccentric bushing
20
and electric sensor
24
detects when lower limit switch
32
indicates alignment bar
30
is in the proper position. In this position, eccentric bushing
28
and the cap of connection member
10
are all locked together. The chamber (not shown) inside eccentric bushing
20
is pressurized relieving the press fit between crankshaft
14
and eccentric bushing
20
, and creating the press fit between the cap
16
of connection member
10
and eccentric bushing
20
. At this time, crankshaft
14
can be rotated to whatever desired stroke position is desired and need in the press operation. Once the desired stroke position is obtained, the high pressure oil (not shown) between eccentric bushing
20
and crankshaft
14
is halted thereby creating the clearance between connection member
10
and eccentric bushing
20
. Double acting cylinder
28
can be energized raising alignment bar
30
(as shown in
FIG. 3
b
) until upper limit switch
34
activates sensor
24
putting alignment bar
30
into the position depicted in
FIG. 3
a
. Spring
26
additionally holds alignment
30
in the up position during mechanical press operation.
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This patent application is therefore intended to cover any variations, uses, or adaptations of the present invention using its general principals. Further, this patent application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.
Claims
- 1. A mechanical press comprising:a press connection member; an eccentric bushing disposed within said press connection member; a second eccentric member disposed within said eccentric bushing creating an interface therebetween, said second eccentric member releasably connectable with said eccentric bushing; a rotatable crankshaft connected to said second eccentric member; a means for connecting said eccentric bushing with said press connection member by a temporary press fit to prevent rotation there between whereby rotation of said crankshaft when said means is activated then causes a press stroke adjustment; and a means for aligning said press connection member and said eccentric bushing during said press stroke adjustment, said alignment means being mounted in said press connection member, said alignment means being selectively actuatable into a positive lock position with said eccentric bushing, said positive lock position with said eccentric bushing defining a first limit of movement for said alignment means.
- 2. The press of claim 1 in which said connecting means comprises fluid pressure applied to the interface between said second eccentric and said eccentric bushing whereby said such pressure permits relative rotation between said second eccentric member and said eccentric bushing while said alignment means engages said eccentric bushing.
- 3. The press of claim 1 in which said connecting means comprises fluid pressure applied to the interface between said second eccentric member and said eccentric bushing that causes said eccentric bushing and said press connection to connect together by temporary press fit connection while said alignment means is engaged by said eccentric bushing.
- 4. The press of claim 3 in which said connection means is in operative communication with said crankshaft.
- 5. The press of claim 3 wherein said second eccentric member and said eccentric bushing form a press fit therebetween prior to creation of said temporary press fit connection.
- 6. The press of claim 1 in which said connection means which is in operative communication with said crankshaft.
- 7. The press of claim 1 in which said eccentric bushing includes an internal cavity in communication with said second eccentric member.
- 8. The press of claim 1 in which said eccentric bushing includes at least one keyway therein, each said keyway being configured for receiving said alignment means therein.
- 9. The press of claim 1 where said alignment means is a bar which engages said eccentric bushing.
- 10. The press of claim 1 where said means of alignment operates through a double acting cylinder.
- 11. The press of claim 1 where said means of alignment includes a detection means to detect the position of said alignment means.
- 12. A mechanical press comprising:a press connection member; an eccentric bushing disposed within said press connection member; a second eccentric member disposed within said eccentric bushing creating an interface therebetween, said second eccentric member releasably connectable with said eccentric bushing; a rotatable crankshaft connected to said second eccentric member; a means for connecting said eccentric bushing with said press connection member by a temporary press fit to prevent rotation there between whereby rotation of said crankshaft when said means is activated then causes a press stroke adjustment; and a means for aligning said press connection member and said eccentric bushing during said press stroke adjustment, said means of alignment including at least one of a double acting cylinder and a spring to hold the alignment means in position to ensure that the alignment means and connection member do not collide during the operation of the press.
US Referenced Citations (16)