US2314980A - Constant pressure wringer - Google Patents

Description

March so, 1943. L. F. I -IAM MAND 2,314,980

' CONSTANT PRESSURE WRINGER Filed March 25, 1940 3' Sheets-Sheep l Mar'chso, 1943. L. F. HAMMAND $314,980

I CONSTANT PRESSURE WRINGER Filed March 25, 1940 s Sheets-Shet 2 Patented Mar. 30, 1943 UNETED STATES ATENT OFFICE 2,314,980 CONSTANT PRESSURE WRINGER Lowell F. Hammand, Chicago, Ill., assignor to Nicholas L. Etten, Waterloo, Iowa 11 Claim The present invention relates to clothes wringers and more particularly to mechanism for controlling the pressure exerted between the wringer rolls.

The principal object of the invention is to provide pressure control devices for a wringer such that the wringer rolls may operate under customary pressures at all times during the normal operation of the wringer and will operate under greatly diminished pressure whenever the pressure rolls are forced apart into abnormal spaced relationship.

Another object of the present invention is to provide wringer pressure control devices comprising a triangular lever operatively interconnecting a fiat leaf type wringer spring with the movable roll of the wringer.

A further object of the invention is to pro vide a wringer pressure control mechanism adapted to cause the pressure rolls to operate under undiminished wringing pressure in normal displacement of the IOlls and to operate under greatly diminished wringing pressure whenever the wringer rolls are moved into abnormal spaced relationship.

Another object of the invention is to provide wringer pressure control devices constituting the triangular lever mounted for free floating movement to permit straight line vertical movement of the wringer roll bearings and to shift the effective point of spring pressure application on the lever.

A further object of the invention is to provide wringer pressure control devices of extreme simplicity and rugged construction adapted to be used in any one of the conventional wringer structures now commonly in use and capable of great economy in manufacture.

Further objects will appear hereinafter.

In the prior art numerous attempts have been made to construct a wringer equipped with pressure control devices whereby the pressure effective between the wringer rolls would not rise to great extremes in the event that the rolls were forced apart into an abnormal-spaced relationship, but insofar as is known to the applicant, these prior art devices have been Objectionable on the ground that they have been inherently complicated, expensive to manufacture and unreliable in operation. 7

In the present invention the desired results have been obtained by the simple expedient of mounting a free-floating triangular lever between each of the bearing blocks of the movable wringer roll and the pressure spring of the wringer.

The arrangement is such that the wringer bearing blocks may move in a straight line vertical direction and this movement will be effective to shift the three operating points of the lever with respect to each other in such a manner as to vary the mechanical advantage existing between the pressure spring of the wringer and the movable wringer roll. 'It will be obvious that in such an arrangement the exact dimensions of the lever may be varied in accordance with the requirements of each individual wringer to provide a pressure control device having the exact mechanical characteristics preferred.

In the preferred construction of the invention the arrangement is such that one of the operating points of the triangular lever is shiftable with respect to the pressure spring and it is, therefore, possible to form a cam surface on the pressure spring in order that any desired mechanical characteristics may be obtained in the mechanism as a whole.

Referring more particularly to the drawings:

Fig. 1 is a longitudinal'sectional view of a characteristic type of wringer constructed in accordance with the principles of this invention;

Fig. 2 is a detail sectional view of the pressure control mechanisms in the position they assume during the normal lateral displacement of the pressure rolls caused by the thickness of the materials being passed between the rolls;

Fig. 3 is a detail sectional view similar to Fig. 2, illustrating the position the mechanisms assume when the pressure rolls are forced into abnormal spaced relationship with each other;

Fig. 4 is a detail sectional view similar to Fig. 2, illustrating the position the pressure mechanisms assume when the pressure rolls are moved into extreme spaced relationship with each other;

Fig. 5 is a detail sectional view illustrating a modified form or the pressure control devices;

Fig. 6 is a fragmental detail sectional view of another modified form of pressure control mechanism; and

Fig. 7 is a perspective view of one of the triangular lever pressure control devices.

The wringer chosen for purpose of illustration' of the principles of this invention comprises in general a main frame iii incl ning a pair of vertical bearing slideways ll and I2 rigidly interconnected at their lower extremities by a longitudinal bottom channel member l3 spot welded or otherwise secured to the vertical bearing slideways H and I2. The top frame Mof the wringer may be secured to the main frame L0 in any c nv a a ne a or exam le. by e lower wringer roll 23 by means of a spur gear 24;

which is adapted to mesh with an internal gear 25 pinned to the lower roll shaft 22. The lower roll shaft 22 is, of course, journaled for rotation in suitable bearings 26 and 21 carried in the vertical bearing slideways II and I2, respectively. It will be seen from reference to Fig. 1 that the bearing 26 is stationarily mounted and is secured in position by the cross pin 28, while the bearing 21 is free for vertical movement limited by the lower bearing support 29 and the cross pin 3|, and is urged upwardly by a light coiled spring 32. The

arrangement is such that whenever the upper roll 33 is forced downwardly into pressure relationship with the lower roll 23, the coil spring 32 will be compressed until the movable bearing 21 seats firmly on the lower bearing support 29. In this position the internal gear 25 will be in the position illustrated in the drawings and will be in mesh with the spur gear 24 carriedby the power drive shaft 2| to complete a rotary driving connection between the power head l6 and the lower wringer roll 23. When the pressure between the rolls 33 and 23 is released, however, the coil spring 32 will act to move the bearing 21 upwardly until the lower roll shaft 22 engages the cross pin 3|. In this position the internal gear 25 and the driving spur gear 2| will be in concentric relationship and since the extreme outer diameter of the spur gear 2| is less than the inside diameter of the internal gear 25, these gears will not engage and the gear 2| may continue to rotate without imparting any motion whatsoever to the wringer rolls.

The upper wringer roll 33 includes a roll shaft 34 j ournaled at each end of the wringer in similar bearings 35 mounted for vertical movement in the bearing slideways H and I2. Each of the bearings 35 is provided with a clip 38 by which the bearing 35 is mounted on a cross pin 31 extending between a pair of triangular plates 38 which cooperate to act as a triangular lever 38 interconnecting the roll bearings 35 with a flat leaf pressure spring 39 adjustably mounted on the top frame M of the wringer by means of a threaded adjustment screw 4|.

The operative connection between the pressure spring 39 and the triangular lever assembly 38 is completed by means of a roller 42 rotatably mounted on a cross pin 43 riveted at each end to one of the triangular plates 38' and adapted to be engaged by the cam surface 44 of the end portion of the flat leaf pressure spring 39. p

A movable fulcrum is'provided for the triangular lever assembly by mounting a pair of links 41 on rivets 48 secured in the side walls of the top frame l4 and pivotally interconnecting the lower ends of each of these links 41 to one of the-triangular plates 38 by means of a pair of rivets 49. This arrangement provides a full floating triangular lever to operatively interconnect the pres sure spring 39 of the wringer with each end of the movable pressure roll 33. The term full floating as used here is intended to define a lever having no fixed mounting point, so that all points of the lever are movable with respect to the wringer frame.

When the top frame l4 of the wringer is secured in operative position on the main frame l8, the cam surface 44 at either end of the spring 39 will bear downwardly against rollers 42 of the triangular levers 38 and will cause each of these levers 38 to tend to pivot downwardly around the fulcrum 49 so that the cross pins 31 will xert downward force on the upper roll bearings 33 and maintain the upper roll 33 in a predetermined pressure relationship with the lower roll 23. It will be understood, of course, that the initial degree of pressure existing between the two rolls 33 and 23 will be adjustable by means of the threaded adjusting screw 4|, but that in the operation of V the machine the triangular levers 38 will also act to control the operating pressure whenever the rolls are forced apart by the thickness of the work passing between them. In the normal operation of the machine this relative spacing movement between the rolls will be relatively small, probably not exceeding one-half inch under normal conditions. Within this range of movement it is often desirable to provide pressure control devices of such design thatas the rolls are urged apart the pressure will increase slightly. This arrangement accomplishes .a highly desirable result in that it provides a light operating pressure when thin articles, such as handkerchiefs, are being passed between the rolls, and gradually increases the pressure when heavier articles, as sheets and blankets, are passing through the wringer. In the present device this increase of pressure in the operating range of the wringer is accomplished by providing the cam surface 44 on each end of the flat leaf type pressure spring 39, such that the initial movement of the triangular levers 38 will cause the rollers 42 to act on the cam surfaces 44 and cause a comparatively large degree of flexing of the spring 39. This arrangement provides means to increase the pressure exerted by the leaf spring 39, but since the triangular levers 38 have shifted in position, as illustrated in Fig. 2, the mechanical advantage between the spring and the roll have been somewhat altered and, if desired, the cam surface 44 may be cut at such an angle that these two factors compensate for each other, and the wringer pressure will remain constant during the normal range of displacement of the upper roll. Such an arrangement is illustrated in Fig. 5, to be described hereafter.

In an emergency, as, for example, in the event that the operator should allow her arm to get between the wringer rolls, it is obvious that the rolls will be forced apart a distance greater than the normal spacing at which the rolls operate. In this event, it will be readily apparent that it is desirable not only that the wringing pressure does not increase to the great extremes encountered in some present-day wringers, but it is also desirable that the pressures be greatly diminished to avoid serious injury insofar as it is possible to do so. The manner in which this is accomplished in the present device is illustrated in Fig. 3, where it will be seen that the roll 42 constituting the center point of the triangular lever 38 has been shifted longitudinally along the spring 39 and the lever 38 has shifted to sharply alter the mechanical advantages existing between the spring and rolls, so that the effective pressure between the rolls 33 and 23 has been reduced almost to zero. V

' In the event that the rolls 33 and 23 are forced apart to their extreme spaced relationship illustrated in Fig. 4, the roller 42 will move inwardly until it crosses the center line between the rivets 48 and the rivets 49. this position, the forc of the pressure spring 39 will be restrained by the links M and will exert no force whatever tending to urge the rolls into engagement. The upper roll 33 will, therefore, be retained in locked position out of engagement with the lower roll 23.

In the modified form of the invention illustrated in Fig. 5, the pressure control mechanism has been arranged to act on the lower roll of the wringer rather than on the upper roll, as in the preferred form of the invention just described. The structure illustrated in Fig. includes a pair of Vertical bearing slideways 51 joined at theirlower ends by cross frame 52 and their upper ends by a top frame 53 releasably latched to theslideways 5| by means of a latch 54, a link 55 and a reset lever 55. The structure is quite similar to the arrangement illustrated in Fig. 1, except that the upper wringer roll 51 is mounted in stationary bearings 58, each of which is locked in position in the bearing slideways 5| by a cross pin 59, which extends through a slot 6| in the sidewall 52 of the slideway and is riveted in the wall of the top frame 53. The lower roll 63 is journaled for rotation in a pair of bearings 68 mounted for vertical slidin movement in the slideways 5i and urged upwardly by a flat pressure spring 5% mounted on a rigid bracket 55 positioned at substantially the mid-point of the lower cross frame 52. comprises a triangular lever 66 mounted on a fixed pivot point 6! rivete in the walls of the lower cross frame 52. This lever 66 is preferably, though not necessarily, made up of a pair of identical plates spaced apart on opposite sides of the spring es. The spring 64 bears against the roller 68 mounted on the rivet 59 and forces the lower roll $3 upwardly by means of the connection established by the link H extending between the pin 12 on the lower roll bearing BE and the pin '!3 on the triangular lever 65. The operation of this pressure control device is substantially the same as the operation of the mechanism illustrated in Fig. 1, except that the cam surface 14 on the end of the spring 6% is cut at an angle calculated to compensate for the change of mechanical advantage that takes place during the movement of the lever 66 through its operating range and thus maintains the constant pressure between the rolls 5'! and 63 until these rolls are moved apart a distance greater than the normal range of operation of the device.

It will also be noted that the spring 54 is mounted on a rigid and stationary supporting bracket 65 which will prevent any rocking movement of the spring at its point of support and cause each end of the roll 53 and spring 64 to operate independently of the other.

The second modified form of the invention is illustrated in Fig. 6. In this modification a triangular lever Si is mounted on a fulcrum 82 suspended from the supporting rivet 83 by the link 84. The roll bearing 85 is mounted on the cross pin 86 and a roller 81 is mounted on the cross pin 88 and adapted to be engaged by the spring 89. The principal difference between this structure and the structure illustrated in Fig. 1, is that the lever 81 comprises a lever of the second class; that is, a lever wherein the point of application of the force to the bearing is between the fulcrum andthe point of application of the spring pres- When the parts assume The pressure control device in this wringer sure, whereas the lever illustrated in Fig. 1, comprises a lever of the third class, wherein the point" of application of the spring pressure is between the fulcrum and the point of application of the bearing pressure.

' The operation of the mechanisms is substantially the same, however, with the single exception that no cam surface has been provided on the spring 8d so that the leverage existing between the spring and roll is entirely dependent on the dimensions of the lever ill. The result of this structure, of course, is that the effective pressure between the wringer rolls will begin to decrease immediately as the rolls begin to move apart as contrasted with the structure illusrated in Fig. 1, in which there is a slight increase in pressure and in contrast with the structure illustrated in Fig. 5, where the pressure remains. f constant.

From the foregoing description it will be ap parent that bypracticing the principles of thisinvention the operating pressure of a conventional type of wringer may be controlled by mechanism of an exceedingly simple and rugged nature. Furthermore, it will be seen that the mechanism here illustrated and described is of such a nature that it may be easily incorporated into the design of the conventional type of wringer now in common use in the industry since the principal parts of the wringer structure, namely, the rolls, the main frame, the top frame. the power head'the pressure release and reset mechanism, and the roll stop mechanism may be constructed exactly as they have been constructed in the prior art, and the pressure control devices comprising the triangular levers and links may be incorporated into almost any modern wringer without the necessity of altering the general appearance or operation of the wrmger.

it will also be seen that the lever and link pressure control mechanisms perform an incidental function at the time when-the emergency release mechanism of the Wringer is operated in that. they act as limit links to prevent the top frame from being thrown too far upwardly when the emergency pressure release is operate While I have shown and described a preferred embodiment of this invention in compliance with the patentstatutes, I am aware that it is subject to numerous modifications and alterations without. departing from the invention spirit and I therefore do not wish to be limited except by the scope of theappended claims.

I claim: 7

1. In a wringer, a frame, a laterally rnovable pressure roll, a fiat leaf pressure spring adapted to exert force acting at substantially right angles to the axis'of said roll; and pressure control mechanisms operatively interconnecting said spring with said roll at each end of said roll, each of said pressure control mechanisms comprising an anchor connection on the frame, a pivotal connection anchored to the roll, and a link and triangular lever of the third class pivotally interconnecting each other and extending between the pivotal anchor connection on the frame and the pivotal connection anchored to said pressure roll, said lever being adapted to operatively engage a cam surface formed on said spring, said pressure control mechanisms being characterized by means responsive to normal lateral displacement of said movable roll to exert undiminished pressure between the wringer rolls, means responsive toabnormal lateral displacement oxfsaid movable roll to diminish the effective pressure between the rolls, and means responsive to maximum lateral displacement of the movable roll to maintain the wringer rolls in spaced-apart relationship.

2. In a wringer, a frame, a laterally movable pressure roll, a flat leaf pressure spring adapted to exert force acting at substantially right angles to the axis of said roll; and pressure control mechanisms operatively interconnecting said spring with said roll at each end of said roll, each of said pressure control mechanisms comprising an anchor connection on the frame, a pivotal connection anchored to the roll, and a link and triangular lever of the third class pivotally interconnecting each other and extending between the pivotal anchor connection on the frame and the pivotal connection anchored to said pressure roll, said lever being adapted to operatively engage a cam surface formed on said spring, said pressure control mechanisms being characterized by means responsive to normal lateral displace" ment of said movable roll to exert undiminished pressure between the wringer rolls, and means responsive to abnormal lateral displacement of said movable roll to diminish the effective pressure between the rolls.

3. In a wringer, a frame, a laterally movable pressure roll, a flat leaf pressure spring adapted to exert force acting at substantially right angles to the axis of said roll; and pressure control mechanisms operatively interconnecting said spring with said roll at each end of said roll, each of said pressure control mechanisms comprising an anchor connection on the frame, a pivotal connection anchored to the roll, and a triangular lever having an end fulcrum extending between the pivotal anchor connection and the pivotal connection anchored to said pressure roll; said pressure control mechanisms being characterized by means responsive to normal lateral displacement of said movable roll to exert increasing pressure between the wringer rolls, means responsive to abnormal lateral displacement of said movable roll to diminish the effective pressure between the rolls, and means responsive to maximum lateral displacement of the movable roll to maintain the wringer rolls in spaced-apart relationship.

4. In a wringer, a frame, a laterally movable pressure roll, a fiat leaf pressure spring adapted to exert force acting at substantially right angles to the axis of said roll; and pressure control mechanisms operatively interconnecting said spring with said roll at each end of said roll, each of said pressure control mechanisms comprising an anchor connection on the frame, a pivotal connection anchored to the roll, and a triangular lever of the third class extending between the pivotal anchor connection and the pivotal connection anchored to said pressure roll, said pressure control mechanisms being characterized by means responsive to normal lateral displacement of said movable roll to exert increasing pressure between the wringer rolls and means responsive to abnormal lateral displacement of said movable roll to diminish the effective pressure between the rolls.

5. In a wringer including a main frame, a top frame, a latch interconnecting said main and top frames, a manually operable latch release, and a reset lever, the combination of a plurality of pressure rolls including a movable roll mounted in bearings for movement in a direction lateral to the roll axis, spring means associated with said movable roll, and pressure control mechanisms operatively interconnecting said spring means and said roll; said pressure control mechanisms being characterized by means to maintain predetermined initial operating pressure between said pressure rolls when said rolls are in contact, means responsive to normal lateral displacement of said movable roll to exert undiminished pressure between said rolls, and means responsive to abnormal lateral displacement of said movable roll to gradually and progressively diminish the effective pressure between said rolls.

6. In a wringer including a frame, a plurality of pressure rolls, and a flat leaf pressure spring adapted to exert force acting at substantially right angles to the axes of said rolls, pressure control mechanisms interconnecting said spring and said rolls at each end of one of said rolls, each of said pressure control mechanisms comprising a triangular lever of the third class including a point of force application with said spring, and means to shift said point of force application between said lever and said spring in response to lateral displacement of one of said rolls.

7. In a wringer including a frame, a plurality of pressure rolls, and a pressure spring, pressure control mechanisms interconnecting said spring and said rolls at each end of one of said rolls, each of said pressure control mechanisms comprising a triangular lever of the third class, a point of engagement between said lever and said spring, and means to shift said point of engagement between said lever and said spring in response to lateral displacement of one of said rolls,

8. In a wringer including a frame, a plurality of pressure rolls, and a fiat leaf pressure spring adapted to exert force acting at substantially right angles to the axes of said rolls, pressure control mechanisms interconnecting said spring and said rolls at each end of one of said rolls, each of said pressure control mechanisms comprising a triangular lever having an end fulcrum including a point of engagement with said spring, and mounting means for said lever adapted to shift said point of engagement longitudinally of said spring in response to lateral displacement of one of said rolls.

9. In a wringer comprising a frame, a spring,'

and a plurality of pressure rolls including a laterally displaceable roll and movable bearings for said roll, pressure control devices operatively interconnecting each end of said spring with one of said movable bearings, each of said pressure control devices comprising an anchor connection on the frame, a pivotal connection anchored to the movable roll bearing and a link and a floating triangular lever of the third class pivotally interconnected with each other and extending between the pivotal connection on the frame and the pivotal connection on the movable roll bearing; and a point of force application operatively interconnecting said floating triangular lever and said spring.

10. In a wringer comprising a frame, a spring, and a plurality of pressure rolls including a laterally displaceable roll and movable bearings for said roll, pressure control devices operatively interconnecting each end of said spring with one of said movable bearings, each of said pressure control devices comprising a triangular lever of the second class, a pivotal anchor connection on the frame, a pivotal connection with the movable roll bearings, and a shiftable point of force application between said lever and the pressure spring.

11. In a wringer including a frame, a plurality of pressure rolls and a pressure spring, pressure control mechanisms interconnecting said spring and said rolls at each end of one of said rolls, each of said pressure control mechanisms comprising a-triangular lever of the second class, a point of engagement between said lever and said spring, and a means to shift said point of engagement between said lever and said spring in response to lateral displacement of one of said rolls.

LOWELL F. I-IAMMAND.

Images