US3539011A

US3539011A - Rotary-drum machines

Info

Publication number: US3539011A
Application number: US768846A
Authority: US
Inventors: Reginald Thomas Hopkins
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1967-11-02
Filing date: 1968-10-18
Publication date: 1970-11-10
Anticipated expiration: 1987-11-10
Also published as: GB1212211A

Description

United States Patent Inventor Reginald Thomas Hopkins [56] References Cited atf r gland FOREIGN PATENTS P 928,042 5 1955 Germany 7. 210/146 Filed Oct. 18, 1968 Patented Nov. 10, 1970 OTHER REFERENCES Assignee General Motors Corporation German Printed Application 1,158,003, November 1963,

Detroit, Michigan 210- 146. a cm'ponum of Delaware Primary Examiner-J. L. DeCesare Pmmy 2, Att0mey-- F. M. Ritchie and w. E. Finken Great Britain 49,789/67 1 ABSTRACT: A centrifugal extraction machine includes a casing, a rotary drum within the casing, a lid on the casing opena- :gT? i2% Q ble for access to the drum, and a lid latch to secure the lid in a raw closed position on the casing. The machine has a brake to U.S. Cl 210/146, brake rotation of the drum, and an interlock between the 210/368 brake and the latch which interlock is operable by mechanical Int. Cl 1304b 7/06 reaction torque of the brake, when the drum is being braked, Field of Search 210/146, to block release movement of the latch and prevent opening of 368 the lid while the drum rotates.

Patented Nov. 10, 1970 r ("0,539,011

Sheet I of 4 Inventor A Home y 1 ROTARY-DRUM MACHINES This invention relates to rotary-drum machines, for example spin driers, clothes washer machines having centrifugal drier drums, or other centrifugal extraction machines having a lid to cover the drum which is 'close d by a latch whenever the drum is rotating butrequires to be opened to fill or empty the drum.

By the invention untimely opening of the lid when the drum is still rotating is prevented by aninterconnection between the catch of the lid a'nd'the rotation of the drum.

The scope of the invention is defined by the appended claims; how the invention may be performed is, particularly described below with reference to the accompanying drawings. i

a One example of a machine in accordance with the invention is shown in FIGSJ to 4 ol' the drawings, in the form of a spin drier for domestic laundry use. In the drawings:

FlCbl is a diagrammatic view, partly in section of a spin I drier accordingto the inventio n, with some parts omitted for clarity;

HO. 2 is a plan of a brake spinner plate according to the inventions X FIG. 3 is a plan of a stop device according to the invention;

FIG. 4 is a plan ofthe lid latchof FIG. 1;

FIG. 5 is a diagrammatic viewtsimilar to FIG. I, of second embodiment of spin drier for domesticlaundry use;

FIG. MS a planof the brake of FlG. 5ointhe direction of the arrow A;

FIG. 7. is a side'view in the direction of the arrow B in FIGS. 5 and tLofthe cable and fixture of FIG. 5;

when the lid unlatched. Within the casing a drum 5 is mounted on a hollow shaft 7 jou rnaled in bearings I05, 106 on a spindle 9 secured to asupport it) near the bottom of the easingl. Near itslower end, the shaft 7 has an enlargement H with a peripherulgroove thci'cin, which forms a pulley fora drive belt (hotshown) from an, electric motor (also not shown). The shaft 7 extends slightly below the enlargement 11. A rotatable brake assemblyis attached to the bottom 13 of the shaft 7, and consists of a brake spinner plate 15 sandwiched between themae hined undersurface 17 of the enlargement 1.1 arid a pressure plate 19, by helical compression springs 21 threaded on bolts 23 screwed into the bottom 13 of the shaft 7. The spinner plate has frictionpads 25 on each face, and has two diametrically opposed

lugs

29, 31 on its peripherytFlG. 2); The lid 3 hasa fixed latch member 33 with two oppositclyfacing barbs 35; .37- along its length, one barb 37 being below the otherbarb'35. A spring-loaded horizontal latch plate 39.slidably mountedinthe casing l has a knob 41 on its outside end-extendingthrough the casing wall. A helical from stop 63, also projects up from the support 10. The push rod 49 also has a contact 67 for making and breaking a drum drive motor energizing circuit through a microswitch 69 secured to the casing 1.

When' wet clothes are loaded into the drum 5 and the machine operated, water or any other liquid is centrifuged out through apertures (not shown) in drum 5. The centrifuged compression spring 43 abuts at one enda stop 45 extending downwardly from theunderside of the plate 39 .near its inner end, the other end of the spring abutting against a fixed abut ment 145. Thus the spring 43 acts to urge the latch plate 39 outwardlyof the casing."l"he plate 39has a slot 47 in it (FIG.

4) whose length is suff cient to allow the passage therethrough of the latch member 33 and one

o fthe barbs

35,37 but not the latch member and both barbs. A vertical push rod 49 is mounted for a'xi al and rotary movement in brackets 57, 157;v on the side of thecasing l. Thepush rod 49has a cranked.

lower end, 149 terminating in a short upturned vertical length or tall 51. A helical compression spring 53 threaded on the rod 49 abuts at one end nstop 55 on therod and at the other end abutsthe bracket 57 iixed to the casingl forthe push rod 49. A cam 59is fixed on theupper end of the push rod. A helical tension spring 61 "(FlCrS. I and 3) is connected between the cranked end 49 of the push rod 49 and the casing] and holds the pushrod end 149 against a stop 63projecting up from the liquid collects on a partition 200 in the casing l, and may be drained therefrom by some suitable means (not shown).

When the spin drier is operating any attempt to open the lid is prevented by the use of the mechanical reaction torque of the braking energy of the spinning drum to lock the lid until the drum is completely stationary. When'the drum is charged with laundry the lid is closed and latch member 33 abuts the end of the push-rod 49 and depresses it against the pressure of the spring 53. This downward movement of the push rod brings the contact 67 into engagement with the microswitch 69 and completes the circuit for energization of the motor to rotate the drum 5. As the lid is closed so the barb 37 of latch member 33 passes freely through the slot 47, the barb 35 then passes through the slot 47 by pressing the plate 39 inwards against spring 43, and the plate 39 is urged outwardly again by the spring 43 to overlie the barb 35 to prevent upward move. ment of the lid and so hold it closed. If the operator now pushes knob 41 'to move the slidable plate 39 inwards and releasethe lid, then the upper barb 35 passes up through the slot 47 as the latch member 33 is pushed up by the push rod 49 raising the lid 3 slightly until the lower barb 37 contacts plate 39, which it does by virtue of the shifted position of plate 39. The upward movement of the rod 49 (to broken line position, FIG. 1) moves the contact 67 away from the microswitch 69 and breaks the motor drive circuit to deenergize the motor. The upward movement of rod 49 also brings its tail 51 up to the path of the lugs on the brake spinner 15 which is revolving with the drum shaft 7. One of the lugs hits the tail 51 and pushes it against the pull of the tension spring over from stop 63 against stop 65 The tail 51 holds the brake spinner fast while the shaft 7 continues to revolve. The friction pads 25 still bear against the undersurface of the enlargement II and against pressure plate 19 and exert a braking effort on them which effort will depend upon the coefficient of friction between the brake pads 25 and the surface on which they bear and the pressure exerted by the spring 21. The reaction torque of this braking effort will be available as a tangential force exerted on the restraining influence; that is the stop 65, and will remain substantially constant until the drum is brought to rest. The movement of the tail 51 from stop 63 to stop 65 turns the rod 49 through the same angle. The cam 59 is also turned and this turning brings. it into contact with the stop 45 on the slidable latch plate 39 and holds the latch plate 39 against return outward movement when knob 41 is released by the operator. Because the return movement of the plate 39 is stopped before it has moved sufficiently to bring the slot 47 into line with the lower barb 37 this barb cannot yet pass up through the slot to release the latch member33 and allow the lid to be opened fullyby the spring hinge 4. The push rod 49, cam 59 and slidable plate39 are held in their places until the drum stops completely since the brake reaction torque is substantially constant and adjusted so as to be greater than the force exerted-v by the spring 61. As soon as the drum stops rotating spring 61 pulls the portion 149 of rod 49 back against thestop 63, and so rotates rod 49 to move cam 59 out of contact with the stop 45. The slidable plate 39 is now free to return fully outwards under spring pressure 43 and so bring the slot 47 into line with the lower barb 37 which can now pass through it and so completely release the latch member 33 so that the lid can openbecause ofits spring-loaded hinge 4.

The spin drier illustrated in FIGS. 5 to 10 has a sheet metal casing 10 with an opening at the top closable by a lid 11 secured to the casing by a spring-loaded hinge 12. A drum and direct-drive electric motor are mounted as a unit l3 vertically within the casing. the drum [3A being supported above the motor 131! by a drive shaft 14. The casing contains a transverse partition 200A. This partition has a central aperture 2008. A drum and direct-drive electric motor are mounted as a unit 13 vertically within the casing, the drum 13A being supported above the motor 138 by a drive shaft 14. The motor 138 is mounted on the underside of the partition 200A by resilient mounts 13C, and the drive shaft 14 extends through the aperture 20013 and supports the drum 13A above the partition. When wet clothes are loaded into the drum 13A and the machine operated, water or any other liquid is centrifuged out through apertures (not shown) in drum 13A. The centrifuged liquid collects on partition 200A and may be drained therefrom by some suitable means (not shown). The drive shaft 14 extends below the motor and on this extension 14A there is fixed a brake disc 15 for frictional engagement by a brake caliper l6 fitted to a slidable plate 17. The slidable plate 17 is mounted on studs 18 on the underside of the motor and to one side of the shaft extension 14A. These studs engage in slots 19 in the plate 17 so that the plate can be moved along the length of the slots. At one end the plate 17 has a fitting 17A for one end ofa Bowden control cable 50, and at the opposite end the plate has two downwardly projecting opposed lugs 178, one on each side, through which a spindle 20 is fixed to form a pivot for the brake caliper 16. The brake caliper 16 has two opposed flat

rectangular plates

21, 22 pivoted at one end on the spindle 20. The two

plates

21, 22 are urged apart by a helical compression spring 23 fitted between them adjacent their pivot end. At the opposite end, the plates are connected together by a toggle joint 24, the limbs of which are held normally in line (full line position FIG. 5) by the compression spring 23. Secured to the centre hinge of the toggle joint is one end of a helical tension spring 25, the other end of which is secured to a bracket 26 on the motor. The

plates

21, 22 each have a pad 120 of friction material secured on their mutually opposed surfaces. The caliper l6 and slidable plate 17 are so mounted with respect to the shaft 14 that the brake disc 15 is sandwiched between the

plates

21,22 of the caliper. A vertical rod 27 mounted in brackets 27A and 278 for axial and rotary movement, is urged upwardly within the casing by a helical compression spring 28 threaded on the rod, and having one end abutting a stop 28A on the rod while the other end abuts the bracket 278. The rod 27 has a cranked lower portion 127, which has a flattened end 29. The Bowden control cable 50 connects this end of the rod with the slidable plate 17 in the manner explained below. Theouter casing 50A of the Bowden cable is secured at one end to the bracket 26 on the motor, and near its other end to a support 202 on the base of the casing 10 (see FIG. 7). A helical compression spring 30 is threaded on to the end of the cable 50 which passes through the flattened end 29 of the rod 27 and has fixed to its end a collar 150 bearing against spring 30. A sleeve 31 is also fixed to the cable 50 and abuts the flattened end 29 of the rod on the opposite side from the spring 30. The sleeve 31 is slidable over the outer casing 50A of the cable.

A lever 32 is pivoted at 132 on a support at the base of the casing. One arm 32A of the lever abuts the cranked portion 127 of the rod 27, which is held against the arm 32A by a helical tension spring 33 connected between the cranked portion 127 of the rod and the casing 10, while the other arm 328 forms a foot pedal protruding from the casing. At its upper end the rod 27 has a cam 34 which can be brought into engagement with a pin 35 on a spring-loaded pivotable slotted latch plate 36, engageable by a barbed latch member 37 on the lid 11. The latch member 37 has two oppositely facing

barbs

38, 39 one below the other. The latch plate 36 is supported in a fixed bracket 236, in which it is pivoted on a pivot pin 237, and spring-loaded in one direction about the pin 236 by a torsion spring 238.

When the spin drier is operating, any attempt to open the lid is prevented by the use of the mechanical reaction torque of the braking energy of the spinning drum to latch the lid until the drum is completely stationary. When the drum is loaded, the lid 11 is closed, which causes the latch member 37 to abut the end of rod 27 and depress it against the pressure of spring 28. This downward movement of the rod 27 brings a stop 2S0 thereon into engagement with a contact arm 251 of a microswitch 252 and moves it to close an electric circuit to energize the motor to spin the drum. As with the embodiment according to FIGS.'1 to 4, the slot 136 in the movable latch plate (slot 136 in this present case) is of sufficient length to allow the passage through it of one but not both of the fixed latch member barbs (38 and 39 in the present case). As the lid 11 is closed the barb 39 on the latch member 37 passes freely through the slot 136 in the pivotable latch plate 36, and the barb 38 then passes through by the necessary pivoting of the plate 36 against spring 238, which then returns the plate 36 so that the upper barb 38 engages the underside of the plate 36 to latch the lid. Both

barbs

38 and 39 can pass freely through a wider slot 236A in the bracket 236.

If the foot pedal 32B is now depressed, while the drum is spinning, the movement of the pedal lever 32 about its pivot causes the inner arm 32A of the lever to push against the cranked portion 127 of the rod 27 and move it against the pull of the helical tension spring 33. Thus rod 27 is turned, causing cam 34 to contact pin 35 and effect sufficient pivoting ofplate 36 to bring slot 136 into alignment with barb 38, allowing the latch member 37 to be pushed up by the rod 27 under the pressure ofspring 28 until the lower barb 39 contacts the plate 36 and is thus prevented from passing up through the slotted plate, and so holds the lid latched. This upward movement of the rod 27 also breaks the contact at 250, 251, to dcencrgize the motor.

The movement of the cranked portion 127 of rod 27 moves the Bowden cable 50 (movement from full line to broken line position in FIG. 7). This movement of the cable 50, caused by the pressure of rod end 29 on sleeve 31 moves the slidable plate 17 in its slots (to the left in FIG. 5, moving from the full line position to the broken line position). This movement of the plate pulls the toggle joint 24 against the resistance of spring 25 and so causes the joint to bend. This bending of the joint pulls the

plates

21, 22 nearer to one another and brings the pads into contact with the rotating brake disc l5 which is squeezed between them. The rotation of the disc 15 against the friction pads 120 induces frictional drag tending to pull the plates round with the disc. This drag, by moving the plate 17 further to the left in FIG. 5 tightens the pads 120 further against the disc, and the brake is in effect a self-energizing one. The drag pulls the cable 50 further against the pressure of spring 30 and so pulls the rod end 127 which causes the rod 27 to turn further to hold the cam 34 against the pin 35 on the latch plate 36 and keep the lid locked. The reaction torque of the braking effort of the pads 120 on the disc 15 will be available as a force exerted on the plate 17 and will remain substantially constant until the drum is brought to rest. This force is transmitted by the plate 15 through the cable 50 to the rod 27 to keep the lid latched. The reaction torque of the brake is substantially constant over the whole of rundown period; and, therefore, if the various spring forces are so chosen that the slidable plate 17 moves quickly to the left after the initiating force is applied, then the plate 17 will remain in that position until the drum stops completely. Then, the combined action of

springs

25, 28, 30, 33 returns the mechanism to its original position and releases the lid 11 by allowing plate 36 to pivot under its spring loading until the slot 136 is in alignment with the lower barb 39 which then passes through the slot and so completely release the latch member 37, so that the lid can open. The spring 30 acts as a return spring for the control cable 50.

The passage of rod 27 through the partition 200 is sealed by a flexible telescopic boot" 201. The centrifuged liquid collects above partition 200, as in the case of the first embodiment described above.

In the first embodiment described above (FIGS. 1 to 4) the

vertical rod

149, 49, acts as an interloek" between the latch and the brake. A similar interlock is provided by the corresponding parts in the second embodiment (FIGS. 5 to 10).

I claim:

1. A centrifugal extraction machine including, in combination, a casing with an aperture therein, a lid hinged to the easing and arranged to close the aperture, a latch member having two locking positions attached to said lid and extending axially into said casing, a manually actuated latch plate, a drum rotatably mounted within said casing and accessible through said aperture, a drive shaft connected to said drum, an electric motor driving said shaft, control circuitry for saidmotor, a I switch in said control circuitry, a brake device attached to said drive shaft operable to brake rotation of said shaft and said drum, a push rod mounted for axial and rotational movement within said casing, latch blocking means attached to the upper end of said rod, movement of said lid to a closed position causing the engagement of said latch with said latch plate in a first locking position and simultaneously moving said rod axially downwardly within said casing and closing said control switch, and brake actuating means attached to the lower end of said push rod, manual actuation of said latch plate to a position disengaging said latch member from its first locking position causing said push rod to move said latch member upwardly into a-second latching position while opening said control switch, said brake actuating means coacting with said brake device to angularly move said push rod to position said latch blocking means to prevent disengagement of said latch from its second locking position while said drum continues to rotate.

2. A machine according toclaim 1 wherein said latch member comprises oppositely extending barbs axially spaced to provide the two latching positions, said latch plate being 3. A machine according to claim l'wherein the latchblocking means comprises a cam rotatable to block the latch against release as long as said rod remains moved angularly by said brake disc lug.

4. A machine according to claim 1, wherein the brake device comprises a brake disc having a peripheral lug, and two parts rotatable withthe drum and sandwiching said brake disc under a spring load; and said push rod includes an abutment movable into engagement with said peripheral lug to arrest rotation of the brake disc and thereby brake the drum and apply to the disc said braking reaction torque.

5. A machine according to claim 1, wherein the brake device comprises a brake disc fixed for rotation with the drum and nonrotatable brake plates sandwiching the brake disc and movable towards it.

6. A machine according to claim 5, in which the brake plates are hinged and are connected by a toggle joint, bending of which operates to move the brake plates towards the brake disc.

7. A machine according to claim 6, in which the hinged brake plates are slidable to effect bending of the toggle joint.