US2862392A - Rocking bed and cam control mechanism - Google Patents

Description

F. A. BLASHFIELD ROCKING BED AND CAM CONTROL MECHANISM Dec. 2, 19258v 5 Sheets-Sheet 1 Filed Oct. l5.- 1955 TTRNEY Dec. 2, 1958 F. A. BLASHFIELD 2,862,392

ROCKING BED AND CAM CONTROL MECHANISM Filed Oct. 15 953 5 Sheets-Sheet 2 IN V EN TOR.'

ATToRNns.

De. 2, 1958 F. A. BLASHFIELD 2,862,392

RooxING BED AND CAM CONTROL MECHANISM 5 Sheets-Sheet 3 Filed 001.. 15. l953 WI l INVENTOR.'

QT y@ M/@a @JMW ATTORNEYS.

De 2 1958 F. A. BLAsHFlELD 2,862,392

' RocKING BED AND CAM CONTROL MECHANISM Filed Oct. 15, l953 5 Sheets-Sheet 4 1N V EN TOR.'

ATTURNEYS.

DeC 2, 1958 F. A. BLASHFILD 2,862,392

ROCKING BED AND CAM CONTROL MECHANISM Filed Oct. l5. 41953 5 Sheets-Sheet 5 QU f1 IN V EN TOR.'

. 2,362,392 j RocKiNG BED AND CAM coNTRoL MECHANISM Y, i

VFloyd A. Blashield, Evanston, Ill., assigner to American .Hospital Supply Corporation, Evanston, lll., a corporation of Illinois Y Y ThisV invention relates to a rocking bed and cam control mechanism. The .cam control mechanism is useful in connection with the control of the rocking movement of the bed, -btt is also obviously useful Vin they control of other structures and elements or devices to be moved.

A primary object of the invention is to provide in connection with the moving of a rocking bed or other type of device, .means for changing the amplitude of movement of the bed -or device during the operation of the rocking or moving mechanism, thus making it unnecessary to stop the motor to effect a change in the amplitude of movement or throw of the cam. A further object is to provide means whereby a device may be actuated by a cam while at the same time providing simple crank or handle means whereby Vthe position of the cam may be changed to alter its throwwhile the operating mechanism y '2,862,392 iatented Dec. 2, A1958 lCC Fig. 5; Fig. 7, a broken, part-sectional view showing the :clutching mechanism and locking mechanism employed;

Fig. 8, a part-sectional detail view of the worm driven by the handle crank; Fig. 9, a perspective view of the chain of geariconnections between the handle crank and the cam member; Fig. 10, a broken, vertical, part-sectional View of a modified form of structure in which a motor is employed for adjusting the position of the cam rather than the manual means shown in Figs. l to 9; and Fig. 11, a side view of the structure shown in Fig. l0.

Referring more particularly to Figsfl and 2, the general arrangement of the structures will be described, it being understood that while reference is made in particular to the rocking bed shown, such bed is merely illustrative of a number of devices with which the cam control mechanism may be employed. In Figs. l and 2, 1t) designates the base equipped with casters 11 and providing a support standard or frame 12. Upon the top of the frame 12 is supported a rock shaft 13. A bed frame 14 is in fulll operation. A still further object is to provide a I device whereby a crank shaft is utilized for rotating a cam having its peripheral portions encircled by a ring and the ring connected to the device to be moved, while at the same time utilizing the Acrank shaft for supporting a member secured to the cam, connections. being provided Vfor moving said member to swing the, cam to different effec-v tive positions upon the crank shaft. Yet another object is to provide a rocking bed, or the like, equipped with a driven crank and a cam eccentrically receiving the crank anda ring freely'receiving the peripheral portions of the cam and .connected to the bed` at one side of its rocking center, means being provided for rotating the cam independently of the operation of the crank for changing the position of the cam thereon. A further object is to provide in connection with the foregoing handle-mechanism supported in line with the driven shaft of the crank for eifecting such changein the position `of the cam. Yet

another object is to provide motor-driven means for opin the set position by such worm and wormV gear, etc.

Other specic objects and advantages will apstructures. pear as the specification proceeds.

The invention is shown, in illustrative embodiments, by the accompanying drawings, in which- Figure l is a perspective view of a rocking bed equipped with cam control mechanism embodying my invention;

Fig. 2, a broken side view in elevation, the bed being shown in a tilted position by dotted lines; Fig. 3, a vertical sectional view, on an enlarged scale, of the crank, .cam mechanism, and the control mechanism therefor; Fig. 4, a plan sectional view of the structure shown in Fig. 3; Fig. 5, an enlarged, brokenside view inelevation of the cam-operating mechanism; Fig. 6, a broken sectional view, the section being taken as indicated at line 6--6 of "with the driven shaft 30, no rocking of the bed will is supported upon the shaft 13 and carries a mattress 15.

If desired, the bed frame 14 may be provided with sectional frames adjustable by means of the links 16. The links 16 are fixed tothe large gears 17 mounted on one side ofthe bed and operated by means of handle driven worm and gear connections. By this means, the bed sections, when moved into the desired position, will remain fixed in such position without further attention because of `theworm and gear structure described.

The standard 12 may be provided with a Xed pointer 18 and a scale 19 fixedto the rock shaft 13 and provided with graduations which will thus indicate the degree of tilting of the bed at any moment. k

The mechanism for rocking the bed will now be described.

Fixed to the bottom of the bed frame are the bearing members 20. Within the mountings V20 is supported a rock member 21 supporting a control shaft 22 and having a bevel gear engaging the vertical bevel gear 22a. The vertical bevel gear 22a is carried by a screw 23 which enters a threaded socket member carried'by the frame member 24. The frame member 24 extend on opposite .sides of an ear 25 carried by a cam ring 26. The cam Vring 26 freely receives a cam 27 eccentrically supported upon the crank shaft 28. The crank shaft 28, as will be shown more clearly in Fig. 6, is rigidly carried by a crank arm 29 Xed to a driven shaft 30. y 1 f y Any. suitable means may be provided for driving the shaft 30. In the specific illustration given, there is provided a motor 31 driving through speed-reducing gears 32 a pulley 33, and, by means of the belt 34, another pulley 35. The shaft upon which pulley 35 is mounted drives through reducing gears 36 the drive shaft 30.

yThe cam and ring mechanism may be of any suitable construction. As shown more `clearly in Fig. 6, the cam 27 is in the form of a disc having an eccentric mounting 37 receiving the crank shaft 28. Between the cam 27 and the ring 26 may be interposed antifriction bearings 38. The straps 24 are provided at their lower ends with ears 39 centrally apertured at 40 to receive the locking pin 41. As shownmore clearly at the top of Fig. 5, the pinv'41y extends through the ears 39 and the central lug 25 carried by the ring 26 so as to secure the ring 26 thus to the straps 24, which in turn are connected by the `screw 23 to the rotatable member 21 on bed 14.'

The ring 26 is confined about the peripheral portion of the cam 27 and theA antifriction bearings 38 carried thereby by means of a locking disc or band 42, the band 42 being held in Yposition by the screws 43, as shown more clearly in Fig. 6. f

Assuming that the parts are -in the position shown in Fig.. 6 with the Vcenter of the cam 27 in alignment freelyreceive the shaft 28.

occur when'the shaft 30 is driven because the crank `shaft '28 will' rotate about theV true center'of'the cam27 and the center of cam 27=.will be in line with the axis of shaft 30. However, if the cam be rotated in either the `bed will occur and the-ring structure"26 will'begin to rise and fall. -Iffthere'forq means can'beprovided for shifting thel positionY of the -cam 27 throughV` mech- Vanisrnv that maybe Voperated while theidrivenshaft '3% Lis in operation, a change in amplitude'of the rocking movement of thebed `can be electedwithout requiring Vthe stopping of `the motor.

I will now describe the mechanism for changing the positionv of thecam '27 while the motor is in operation. v

The cam control mechanism-shownin the drawings employs rst a gear 44,' which is apertured centrally to i VThe Vgear '44 which thus may operate independently of shaft 28,'isbolted directly to the cam 27, employing'three bolts 45. `Thus,"when the gear 44 is rotated, it requires-a similar movement of cam 27 and the cam 27'may'be'thus caused to move in a circular path aboutthe shaft 28 and thuseto'vary the throw of the cam.

Gear connections are provided for rotating the large gear 44 which has been described as bolted directly to the cam 27. For the Apurpose `of clarity, I`have Vshown such gear connections in Fig. 9. It will be noted that a pinion -gear 46 meshes with the large gear 44 and is fixed upon va shaftl 47 carrying a worm gear 48. The worm gear 48 `meshes with` a worm 49 on shaft 50. The shaft 50 carries a bevel gear 51 meshing with another bevel gear 52 Acarried by shaft 53. The shaft 53, through several clutch connections, is connected to a handle on crank 54. Thus, when the handle 54 is turned with the clutch ends so as to rotate shaft 53, there isa rotation of gears 52,51, 49, and finally pinion gear 46 meshing with the large gear 44 which is bolted tothe cam 27. By this means, the cam 27 may be rotated manually through the rotation of the handle or crank 54 to change the setting of the cam 27 and thus vary its throw. Such change of `the cam is Veffected without requiring the stopping of the motor and while, in fact, the motor is in full operation.

The clutch and locking mechanism is important for the following reason. InV the Aoperation of the crank shaft, resulting in movement of the parts, there is found to be some slight creeping ofthe adjustment parts or gears, and'while such change is extremely small, over a substantial period of timethere may be a decided change in the amplitude ofthe-movement of the cam away from the desired setting. lTo Vavoid this, I provide a locking mechanism-and clutch mechanism which will now'be described.

Asshown-more clearly in Fig. 3, I provide'within the casingSSithe-xed shafte56=having a depending fixed support'f57. YYThe fixed support 57 is shown with`the clutch mechanism parts LVAbest in'Fig. 7. observed'fthat the fixed part57` is provided with a recess 58 adapted to receive a locking pin59 threadably received within theAslidable memberl60. A ring member 61 is Vrfixed to the shaft 53 by means of vpinl 62, yand is aperktured at v-63 to receive the outer free end-of-pin`59- 5A compression spring-64 is received within oppositerecesses in the members -60 and 61 so as to ordinarily Vurge "the memberv 60 toward the fixed abutment or support -57. It will be observed that thememberO has a substantial portion projecting outwardly Vbeyond the abutment 57 soas yto permitit to beengaged and movedrinwardly Vto* retract the pin 59 from the recess 58. vThe handle orV crankf54-is tiXed to a sleeve 65, and the sleeve 65,*

having running shaft66a, isA provided'at its inner end with a clutch tongue. 66 adaptedfto" engage a clutch'in shaft'53. vA .lightsp'ring 68 may be employed tomaintain the sleeve 65 spaced from'the vmember 60, and in n will be Y the illustration given, the spring 68 extends between the In operating the clutch, lthe crank handle 54 is moved inwardly to bring the end of the sleeve into engagement with the slidable member 60 and as the member 60 is pressed inwardly, the locking pin 59 is detached from the recess 58, thus permitting the shaft 53 to be freely rotated, andewith the squared tongue 66 engaging the squared recess 67, rotation of-shaftl 53 is readily effected.

It is desired to provide means for indicating the position of the camafter it hasbeen moved and thus to determine the amplitude of movement. To.y accomplish this, I provide the casing 55 on its outer side with a circular scale70 andV provide a pointer 71 lfor cooperation therewith. The pointer 71, as shown more clearly in Fig. 7, is mounted upon a disc'72 secured by the setscrew 73 to a hub member 74 freely mounted upon shaft 53. The hub member 74 is equipped at `its inner end with a gear"75which,"in turn, meshes with a gear 76 freely mounted bythe pin 77 upon the end'of the shaft-28.

Fixed-to the gear '76 is a roller 78 connected by a strap 79 to the large gear 44 bolted to .the cam 27. As shown more'clearly in'Fig. 6, the bracket 79tis secured by a threaded-pin 80 to an inner portion of the gear 44. with this structure, when the .gear 44 is rotated, there is produced'a corresponding rotation of the gearv 76 on shaft-28 and gear 75 on the hub '74, thus producinga rotation ofthe pointer'71 in line with the graduations on scale70.

Y Operation -a fixed crank arm 29. and thereby drives the crankshaft 28.

The cam disc or wheel-27 mounted eccentrically upon crank shaft28 rotates to raise and lower the cam 27, depending upon the position of the cam. As the cam V27 rises and falls with-the rotation of thecrank shaft 28, the sleeve or ring'26 similarly rises and falls, carrying with it the ear 25y and thereby the metal straps .24 and the screw 23, thus transmitting` the movement to -the bed 14 there-above and rocking the bed.

The shaft 53v is concentric with shaft 30, and as gear -44 gyrates, gear 46, which is in -mesh therewith,4 also gyrates.

The casing 55 andeverything contained-and attached therewith rotates. When the cam is rotated yso -as to bring the-center ofthe cam in line with the drive shaft i310, as described in column 3, no longitudinal movement of the connecting link 26 is effected and there 'is no rocking of the-bed. VHowevenfas the cam is rotated in either direction upon the shaft 28 so as to 'bring the center of the cam off-center with respect to the driven shaft 39, rocking of the bed 'occurs and to effect this change, the handle may be'operated in either direction.

To change the position of the cam so as to vary its throw,v the operator new rotates Athe handle 54, after `pressing it 4inwardly so as to ree'the member 60 and the pin 59 from the recess-158 and; toy bring the clutch parts -66andl 67 into engagement. By this means, shaft 53 is rotated and thence throughv gears 52 and 51, shaft 56, worm 49, worm gear 48,- shaft 47, and pinion 46,

`:the large gear ".44 which isbolted` to the cam 27 isA rotated. This causes the cam 27 to move bodily about the crank shaftZS to any selected position. Such move- Vment is accomplished during 'the rotation of the crank shaft.28.and without affecting the regular operation of ethf'rmotor and the driven shaft 30. Simultaneously, with any shiftingof the position` of: the cam, there is .pro

'duced .through the` connector strap 179 a shifting of the free gear 76 and thereby the gear 75 and hub 74 carrying the pointer disc 72.

While, in the foregoing, I have described a manuallyoperated control for shifting the position of the cam, it will be understood that other means may be provided for effecting such change. If desired, a motor may be provided for this purpose and instead of the nurse having to bend downwardly to operate the manual crank, the change may be effected by simply throwing a switch button located at a convenient point on the bed and thus operating a motor to increase or decrease the amplitude of the rocking movement. In Figs. and l1, I have shown such motordriven means, and since the parts are to a large degree the same in these gures as those shown in the preceding figures, it will only be necessary to refer to the added parts.

In Figs. 10 and l1, there is shown a motor 81 which drives, through reducing gears within the casing 82, a shaft 83 carrying a bevel gear 84. Meshing with gear 84 is another bevel gear 8S, and through the chain of gears shown there is driven the Worm 49a, worm gear 48a mounted on shaft 47a, and thereby through a pinion the large gear 44a which is bolted to the cam 27a.

In the operation of the structure shown in Figs. 10 and 1l, the motor drives through the chain of gears shown the large gear 44a and operating exactly as the gear 44 heretofore described, produces a rotation of the cam 27 about the crank shaft to change the throw of the cam.

While the structure has been described in connection with a rocking bed, it will be understood that the mechanism is applicable to a great variety of machines in which an oscillating or reciprocating movement is desired or other movements which may be effected by a cam as described, and the cam control mechanism herein described may be effective for the control of such machines. The use of a hospital bed as an illustration of the use of the cam control mechanism is desirable because of the effectiveness of such control in connection with a hospital bed, whereby a patient will not be disturbed in the operation of the mechanism, the change of amplitude of movement being effected without stopping the machine; however, it will be understood that the illustration is not limiting in character but merely sets forth one of the many devices which may be used in connection with a cam control mechanism.

While, in the foregoing specification, I have set forth specific structures in considerable detail for the purpose of illustrating embodiments of the invention, it will be understood that such details of structure may be varied widely by those skilled in the art without departing from the spirit of my invention.

I claim:

1. In element-moving mechanism, a frame, a driven y shaft mounted therein, a crankshaft fixed to one end of said driven shaft and having its axis in spaced parallel relation thereto, a cam member having an eccentric mounting receiving said crankshaft and having its center alignable with said driven shaft, a ring freely receiving the peripheral portions of said cam, connecting means between said ring and said element to be moved, control means rotatably supported in general alignment with said driven shaft but longitudinally spaced therefrom, a rotatably mounted handle, said handle 'and' control means being normally unconnected for independent rotation of said control means with reference to the handle, and selectively operable kconnecting means between said handle and said control means for locking said control means and handle against independent rotation, whereby, said 6 handle may be connected with said control means by said second-mentioned connecting means for rotation of said cam upon said crankshaft without interrupting rotation of said drive shaft.

2. In element-moving mechanism, a frame, a driven shaft mounted thereon, a crankshaft actuated by said driven shaft, a cam member apertured eccentrically to receive said crankshaft and having its center alignable with said driven shaft, a ring freely receiving the peripheral portions of said cam, a gear apertured to receive freely said crankshaft and fixed to said cam, rotatable control means independent of said crankshaft and longitudinally spaced from said driven shaft for rotating said gear to change the position of the cam thereon, and a rotatable handle selectively and axially movable between a normal inoperative position wherein said handle is freely disengaged from said control means and an operative position wherein said handle engages said control means for rotation of said cam upon said crankshaft as said handle is turned, said handle being movable into its operative position for changing the position of said cam while said driven shaft is being rotated.

3. In element-moving mechanism, a frame, a driven shaft member mounted thereon, a crankshaft carried by a crank arm on the driven shaft, a cam member apertured eccentrically to freely receive said crankshaft and having its center alignable with said driven shaft, a ring freely receiving the peripheral portions of said cam, connecting means between said ring and said element to be moved, rotatable control means longitudinally spaced from said driven shaft for turning said cam'to change its position upon said crankshaft, and a rotatable handle selectively and axially movable between a normal inoperative position wherein said handle is freely disengaged from said control means and an operative position wherein said handle engages said control means for rotation of said cam upon said crankshaft as said handle is turned, said handle being movable into its operative position for changing the position of said cam while said driven shaft is being rotated.

4. In an element moving mechanism, a frame, a driven shaft mounted thereon, a crank shaft xedly secured to one end of said driven shaft and having its axis in spaced parallel relation to the axis of said driven shaft, a circular cam member apertured eccentrically to rotatably receive said crank shaft, a ring freely receiving the peripheral portion of said cam member, a gear centrally apertured to receive freely said crank shaft and fixed to said cam member, a control shaft operatively associated with said gear for rotating the same upon said crank shaft, and actuating means normally disengaged from said control shaft but being movable into an engaged position therewith for rotating said control shaft and for thereby rotating said cam member upon said crank shaft, said actuating means being movable between engaged and disengaged positions while said driven shaft is being rotated.

References Cited in the le of this patent UNITED STATES PATENTS 421,297 Mills Feb. 11, 1890 540,394 Leitch June 4, 1895 1,700,966 Baerbalck Feb. 6, 1929 2,036,625 Garratt Apr. 7, 1936 2,241,378 Evans May 13, 1941 2,242,715 Woodford May 20, 1941 2,445,258 Beem July 13, 1948 2,592,237 Bradley Apr. 8, 1952 2,696,207 Bushnell Dec. 7, 1954

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