US3575022A

US3575022A - Rotary drive assemblies

Info

Publication number: US3575022A
Application number: US818534A
Authority: US
Inventors: Jonathan Peter Steele
Original assignee: Hoover Co
Current assignee: Hoover Co
Priority date: 1968-04-29
Filing date: 1969-04-23
Publication date: 1971-04-13
Anticipated expiration: 1988-04-13
Also published as: GB1270255A; NL6906531A; SE350547B; DE1921671A1; FR1597121A

Abstract

A tumbler-type washing machine has a horizontal axis rotary drum capable of periodically reversed rotation at slow speed for washing, or rotation at high speed in one direction for centrifugal extraction. The drum is driven by a belt drive extending directly from the shaft of an electric motor which during washing can be periodically reversed. An extraction pump for emptying the drum is also driven by the motor via a drive assembly. The drive assembly for the pump has an input rotary member connected directly to the motor and an output rotary member connected directly to the pump. The input and output rotary members form part of a train of rotary members two of which are capable of rotary movement with respect to one another through a lost motion arc during the periodical reversal of the motor. In this way the pump is not driven during the washing operation. When, however, cooperating shoulders on the said two of the rotary members of the train engage one another, after the members have been driven relatively to one another in either direction through an arc which is as great as the lost motion arc, the input member will drive the output member so as to drive the pump.

Description

United States Patent [72] Inventor Jonathan Peter Steele London, England [21] Appl. No. 818,534 [22] Filed Apr. 23, 1969 [45] Patented Apr. 13, 1971 [73] Assignee The Hoover Company North Canton, Ohio [32] Priority Apr. 29, 1968 [3 3 Great Britain [3 l 20,226/68 [54] ROTARY DRIVE ASSEMBLIES 8 Claims, 4 Drawing Figs.

[52] US. Cl 68/24,

68/208 [51] Int. Cl D06f 29/00 [50] Field of Search 68/24, 208

[56] 4 References Cited UNITED STATES PATENTS 3,033,014 5/1962 Neyhouse et al. 68/19 3,342,085 9/ l 967 Brundage 74/785 Primary Examiner-Emest R. Purser Assistant Examiner-Joseph H. McGlynn Attorneys-Alfred G. Gross and Elmer A. Johnson ABSTRACT: A tumbler-type washing machine has a horizontal axis rotary drum capable of periodically reversed rotation at slow speed for washing, or rotation at high speed in one direction for centrifugal extraction. The drum is driven by a belt drive extending directly from the shaft of an electric motor which during washing can be periodically reversed. An extraction pump for emptying the drum is also driven by the motor via a drive assembly. The drive assembly for the pump has an input rotary member connected directly to the motor and an output rotary member connected directly to the pump. The input and output rotary members form part of a train of rotary members two of which are capable of rotary movement with respect to one another through a lost motion are during the periodical reversal of the motor. In this way the pump is not driven during the washing operation. When, however, cooperating shoulders on the said two of the rotary members of the train engage one another, after the members have been driven relatively to one another in either direction through an are which is as great as the lost motion are, the input member will drive the output member so as to drive the pump.

Patented A ril 13, 1971 v 3,575,022

3 Sheets-Sheet l 18 q 27 q I I 10E.

SPEED A 7 CONTROL TIMER REVERSE 4 SWITCH B 19 20 1; 36 37 38 22 51 03 mm 4 MOTOR 42 44 ,35 J PUMP 43 36 Q INVENTOR JONATHAN P- Swan. BY QWM ATTORNEY Patented April 13, 1971 I 3,575,022

3 Sheets-Sheet 2 INVENTOR JONATHAN P. S-nu-e BY Wit/Siam ATTORNEY Patented April 13, 1971 3,575,022

3 Sheets-Sheet 5 INVENTOR JQNA'FHAN P, 51cm. BY M ATTORNEY ROTARY DRIVE ASSEMhLIES This invention relates to washing and/or centrifugal extraction machines and to rotary drive assemblies therefor. There are occasions when it is desirable to provide a limited, timed, rotary drive of an input shaft in a clockwise or anticlockwise direction without rotating an output shaft but to be able to have an output drive if the rotation of the input shaft is continuous in either direction. For example at the present time it is known to use a reversible motor for the driving of a rotary drum of a tumbler-type washing and centrifugal extraction machine, the motor being reversed at say l2-second intervals to reverse the direction of the drum during a low-speed washing operation. With such an arrangement it is clearly impossible also to have a direct drive from the motor to an extraction pump where the pump requires continuous rotation in one direction for its operation.

As a result it has previously generally been necessary to provide either an independent motor for the extraction pump or a clutch arrangement whereof the clutch is engaged to drive the pump only at appropriate times in a washing machine programme. Such extra motors, clutches, and ancillary mechanisms and circuits inevitably complicate the machine as a whole and increases its overall cost.

Accordingly one of the principal objects of the present invention is to provide a washing machine with a pump drive of a simple and robust nature which avoids the use of clutches, independent motors or other electromechanical devices to drive it. By the use of the invention it is possible to use a direct belt drive from the shaft of a motor which is also employed in a reversible manner to drive another part of a washing machine such as a rotary drum.

Another object of the invention is to provide an arrangement whereby a pump in a washing machine can be driven only during certain desired parts of a washing machine programme even though a connection exists whereby the reversible motor may drive the pump directly e.g. by a belt drive, when desired.

A further object of the invention is to provide a novel drive assembly for a washing and centrifugal extraction machine wherein a rotary drum e.g. of the horizontal axis tumbler type, and an extraction pump for the drum may be driven by the same motor which is of reversible type to permit the drum to be periodically reversed for washing operations or alternatively to run continuously in one direction to provide a pump drive.

These and other objects are attained by providing a washing machine (which may be simply a machine which has no centrifugal extraction facility or alternatively a combination machine which provides for tumbling at low speed during washing and also rotation at high speed for centrifugal extraction), with a reversible electric motor connected in each direction of rotation of the motor shaft to drive a first rotary part such as a drum, reversing means to reverse the direction of rotation of the motor shaft periodically, means connecting the motor shaft in each direction of its rotation to drive the said first rotary part, and a drive mechanism extending from the electric motor to a shaft of a pump, the said drive mechanism including a rotary input member adapted to be driven by the motor and an output member adapted to drive the pump shaft and a train of rotary members extending between the input and output members, two of the said rotary members being capable of rotary movement with respect to one another in either direction, without the one driving the other, through a lost motion are and without a drive being transmitted between the input and output members, the said two members affording cooperating driving shoulders which are adapted to engage one another after the two members are driven relatively to one another in either direction through an arc which is as great as the lost motion are and after such engagement to impart a drive between the input and output members and hence impart a drive between the motor shaft and pump shaft.

Preferably the lost motion are is less than 360 so that the train of rotary members provides a gear ratio which ensures less than one revolution of the output member during a period between two reversals of the direction of rotation of the motor.

The train of rotary members may include an epicyclic gear having an input pinion arranged to drive a floating planet gear which cooperates with a pair of annular members having inwardly facing gear teeth one of which annular members comprises the output member and is connected to the shaft of the pump and other of which comprises an intermediate member having a greater number of teeth than the output member and which is driven relatively to the output member by the planet gear until the said cooperating shoulders engage one another whereafter the said other member will rotate the output member to drive the pump.

The accompanying drawings illustrate one specific embodiment of the invention by way of example.

FIG. I diagrammatically illustrates a washing machine of the horizontal axis tumbler type and incorporating an emptying pump which is driven in accordance with the present invention;

FIG. 2 shows a front elevation of the pump drive assembly partially broken away and shown in section to illustrate certain internal parts;

FIG. 3 is a view similar to FIG. 2 but showing other internal parts; and

FIG. d is a side elevation, partly in vertical cross section, of the assembly of FIG. 2 and 3.

Referring firstly to FIG. I this illustrates diagrammatically a washing machine of the horizontal axis tumbler type having an external appearance casing within which is resiliently mounted an assembly ill including an outer stationary tub 12 which is suspended from the outer appearance casing I0 by coil springs 13. Mounted to rotate within the tub 12 is a perforated wash drum 15 having a shaft 16 driven by a pulley 17. The pulley 17 is connected by means of a belt 18 to a further pulley I9 on the shaft 20 of a reversible motor 22. Extending from a socket 26 on the rear wall of the casing 10 are power leads 27 and 28 which supply a timer 30. By means of further leads 31 and 32, extending from the leads 27 and 23 respectively, a reverse switch 33 is energized, the lead 32 incorporating a speed control 34 for a purpose to be described. The timer is suitably connected either mechanically or electrically, as diagrammatically indicated by the arrows A and B, to the speed control 34 and the reverse switch 33 respectively.

The reversible motor 22 is diagrammatically shown as having three supply leads 36, 37 and 35 extending thereto from the reverse switch, the direction of rotation of the motor being dependent upon which of the leads 37 and 38 is at any one time supplying power to the motor with the third lead 38.

This is a conventional arrangement whereby the timer can be arranged via the connection B to cause the reverse switch periodically to change the direction of rotation of the motor to provide for reversal of the direction of rotation of the wash drum 15 during low-speed tumbling operation for washing purposes.

For centrifugal extraction the drum 15 is rotated at high speed by the same drive for which purpose the timer 30, via its connection A to the speed control 34, causes an appropriate change in speed for the motor 22 when it is desired to change from a tumbling to an extraction operation.

For extraction purposes the machine incorporates a pump having its inlet as connected by means of a hose 37 to the lower side of the tub I2. The outlet 39 of the pump is connected via an outlet hose 40 to an outlet connection 4t.

As will be explained with reference to other FIGS. the pump 35 has a shaft i3 driven by a pulley 44 via a rotary drive assembly 42 which only effects a driving connection to the pump in certain circumstances. The pulley 44 is connected by a belt 45 to a further pulley 511 also mounted on the motor shaft 20. In this way the pulley 44 rotates whenever the motor shaft 20 rotates, irrespective of the direction of rotation of this motor shaft.

The pulley 44, as shown in FIG. 4, has a pinion 46 integrally formed therewith, the pulley and pinion being mounted to rotate freely with respect to the pump shaft 43. Mounted to be driven by the pinion 46 is a floating planet gear 48 having a flange 47 at its end adjacent the pulley 44, this flange 47 being located by a slot 51 formed between the pulley 44 and the pinion 46. Externally, the floating planet gear 48 meshes with internally facing

teeth

49 and 50 of a pair of circular members, namely an intermediate annular gear member 52, and an output gear member 53 which is rigidly secured to the shaft 43 of the pump. As shown in FIGS. 2 and 3 the

members

52 and 53 are provided with

cooperating stops

54 and 55 respectively which, whilst permitting relative rotation of the

members

52 and 53 through less than one revolution, when brought into engagement with one another will rotate together and drive the pump.

H6. 2 shows the floating planet gear 48 with its external teeth 60 meshing with the internal facing teeth 50 of the output gear member 53 whilst FlG. 3 shows the construction with the output gear member 53 removed to illustrate the pinion 46, and the floating planet gear 48, the latter engaging the internally extending teeth 49 of the intermediate annular gear member 52.

The pinion 46 has 17 external teeth whilst the floating planet gear 48 has 16 external teeth. The annular intermediate gear member 52 has 50 internally facing teeth whilst the output gear member 53 has 49 internally facing teeth.

ln this way, whilst the

stops

54 and 55 are out of engagement with one another, the output gear member 53 can be regarded as a stationary gear of an epicyclic train with the pinion 46 forming the input gear. This will produce planetary movement of the planet gear 48 which reacts against the stationary output gear member 53. Due to the fact that the intermediate annular gear 52 has one more tooth than the output gear member 53 each planetary orbit of the planet gear 48 will cause slight relative movement between the

gear members

52 and 53 and, therefore, corresponding relative movement between the

stops

54 and 55. Assuming the numbers of teeth are as referred to above the gear ratio obtained with this construction between the input pinion 46 and the output gear member 53 is 194:1.

In practice the pulley 44 will only be driven through some 100 revolutions during a l2-second running period of the reversible motor 22 when this is running at 500 rpm. Accordingly, assuming that the

stops

54 and 55 are initially in engagement but the instant direction of rotation of the motor is such that the stop 54 moves away from the stop 55, the 100 revolutions of the pulley 44 will not cause the stop 54 to rotate right round into engagement with the stop 55 on its opposite side since after 12 seconds the direction of rotation will be reversed. Therefore whilst the motor is continually reversing to alternate the direction of rotation of the wash drum of the washing machine during, say, a washing cycle the intermediate annular gear 52 will be rotated to and fro without imparting a drive to the stop 55.

Hence the pump 35 will not be driven during the washing cycle.

It will be seen from HO. 4 that the intermediate annular gear 52 has axially extending

flanges

60 and 61. The flange 60 cooperates with a radial flange 63 integrally formed on the pulley 44 substantially to close one end of the assembly 42. The other flange 61 extends outside an axially extending flange 65 of the output gear member 53 which flange 65 bears on its interior the inwardly directed teeth 50. Thus the

flanges

61 and 65 although spaced slightly from one another effectively close the other end of the assembly 42.

When it is desired to empty the washing container, the

motor is arranged to be driven continuously in one direction so that after a short period the stop 54 will engage the stop 55 and will drive the stop 55 and hence the pump.

it will be appreciated that since the pulley 51 for driving the pump pulley 44 is secured to the motor shaft 20 the pump pulle 44 will be rotated continuously irrespective of hthfe e motor s a t direc ion of rotation or speed of rotation of t 20. Hence the continuous rotation of the motor shaft 20 can occur either during slow-speed tumbling operations for example during initial stages of emptying of the machine, or during a high-speed centrifugal extraction operation. The pump is therefore designed to operate at either of these speeds. The speed control 34 is utilized to determine whether the motor is driven at tumbling speed or centrifugal extraction speed.

lclaim:

l. A washing machine including a first rotary part, an electric motor, reversing means whereby the direction of rotation of the motor shaft may be periodically reversed, means connecting the motor shaft in each direction of its rotation to drive the said first rotary part, a drive mechanism extending from the electric motor to a shaft of a pump, the said drive mechanism including a rotary input member adapted to be driven by the motor and an output member adapted to drive the pump shaft and a train of rotary members extending between the input and output members, two of the said rotary members being capable of rotary movement with respect to one another in either direction, without the one driving the other, through a lost motion arc and without a drive being transmitted between the input and output members, the said two members affording cooperating driving shoulders which are adapted to engage one another after the two members are driven relatively to one another in either direction through an are which is as great as the lost motion arc and after such engagement to impart a drive between the input and output members and hence impart a drive between the motor shaft and pump shaft.

2. A machine as claimed in claim 1 in which the lost motion are is less than 360.

3. A machine as claimed in claim 1 wherein the output member is secured to the pump shaft and the input member comprises a pulley arranged to be driven via a belt from a pulley on the motor shaft.

4. A machine as claimed in claim 3 including an epicyclic gear having an input pinion arranged to drive a floating planet gear which cooperates with a pair of annular members having inwardly facing gear teeth one of which annular members comprises the output member and is connected to the shaft of the pump and the other of which comprises an intermediate member having a greater number of teeth than the output member and which is driven relatively to the output member by the planet gear until the said cooperating shoulders engage one another whereafter the said other member will rotate the output member to drive the pump.

5. A machine as claimed in claim 4 wherein the output member is connected to the pump shaft which shaft passes through and supports the input pinion.

6. A machine as claimed in claim 4 wherein the input pinion is secured to a pulley by which it is driven by the motor shaft.

7. A machine as claimed in claim 6 wherein the pinion and pulley are integrally formed.

8. A machine as claimed in claim 7 wherein a substantially radial wall formed on the pulley and a substantially radial wall formed on the second annular member are separated by a space within which the planet gear rotates, the outer circumference of the said space being substantially closed by axially extending flanges on the first annular member.

Claims

1. A washing machine including a first rotary part, an electric motor, reversing means whereby the direction of rotation of the motor shaft may be periodically reversed, means connecting the motor shaft in each direction of its rotation to drive the said first rotary part, a drive mechanism extending from the electric motor to a shaft of a pump, the said drive mechanism including a rotary input member adapted to be driven by the motor and an output member adapted to drive the pump shaft and a train of rotary members extending between the input and output members, two of the said rotary members being capable of rotary movement with respect to one another in either direction, without the one driving the other, through a lost motion arc and without a drive being transmitted between the input and output members, the said two members affording cooperating driving shoulders which are adapted to engage one another after the two members are driven relatively to one another in either direction through an arc which is as great as the lost motion arc and after such engagement to impart a drive between the input and output members and hence impart a drive between the motor shaft and pump shaft.

2. A machine as claimed in claim 1 in which the lost motion arc is less than 360*.