GB2189306A

GB2189306A - Program indication in a domestic appliance

Info

Publication number: GB2189306A
Application number: GB08703872A
Authority: GB
Inventors: Walter Menzel
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-04-15
Filing date: 1987-02-19
Publication date: 1987-10-21
Also published as: DE3612649C1; GB2189306B; GB8703872D0

Abstract

A program-controlled household appliance comprises a panel body (2) with a viewing window (6), and an indicating device which is arranged in the body (2) and comprises gearing driving a toothed rack (7) carrying a sliding indicator (8). In one end setting of the rack, a pinion (17) on a pivotable rocker (19) is brought out of engagement with the toothing (16) of the rack and the rack together with the indicator is pushed back into a starting position by a restoring spring (26). Actuation of the indicator is via a toothed input member (14) which moves the rack (7) via meshing gears (15 & 17). The gear (15) is mounted on the same bearing shaft (18) as the rocker (19); the pinion (17) is rotatably mounted on the rocker (19). Disengagement of the pinion (17) from the rack toothing (16) is achieved by contact of a cam follower (23) on the rocker with a widened tooth or abutment (24) on the input member (14). <IMAGE>

Description

SPECIFICATION Program indication in a domestic appliance The present invention relates to a domestic appliance and has particular reference to the indication of program rundown in a prog rnm-contrnlled appliance, for example a clothes washing ordishwashing machine.

In a known indicating deviceforthis purpose (DE-G M 82 29 737), a rotary knob is connected with the program control device ofthe appliance and an indicating body, movable to and fro byway of a gear, is arranged behind a panel provided with at least one viewing window at the front side and displaying markings. In that case, the rotary knob sits directly on the actuating shaft of the program control device, stands in entraining connection with a toothed ring notched into the panel from the rear side and is coupled through entraining members with the toothed ring. This in turn is coupled bywayofa toothed rack gear with a pointer which sits on the rack and is displaceable in front of or behind the viewing window of the indicator.In this indicating device, the rotary knob is constructed to be rotatable to and fro only in an angular range limited by the toothed rack. In the case of a forced excess rotation, the indicating device could be damaged.

In DE-GM 8231 565 there is disclosed a rotary knob arrangement which, bymeansofaCardanjointis suitable for compensating for axial displacement, due to production tolerances, between the central axis of the actuating shaft of the program control device and the central axis of the rotary knob arranged displaced in a panel body.

There remains a need for an indicating device which is reliable in operation and simple in construction, so that precise indication of rundown of a program is possible.

According to the present invention there is provided a domestic appliance provided with a control device to control operation of the appliance according to program and with indicating means operable to indicate rundown of such program and comprising a panel with a transparent viewing window, an indicator member connected to a rack and movable between two end positions to travel across the window and past markings indicative of the rundown of the program, first resilient means to urge the indicator member into one end position thereof associated with the start of the program, a rocker which carries a pinion rotatable about a first axis and which is pivotable about a second axis spaced from the first axis to move the pinion into and out of engagement with the rack for driving the indicator member in direction from said one end position to its other end position, second resilient means to urge the pinion into engagement with the rack, an intermediate drive element rotatable about the second axis to drive the pinion, and an input drive element which is rotatable about a third axis by the control device in dependence on rundown ofthe program to drive the intermediate drive element and which is provided with cam means so co-operable with the rocker during rotation of the input drive element through an angular position associated with the end of the program as to cause the rocker to move the pinion out of engagementwith the rack, the first resilient means being arranged to return the indicator memberto said one end position when the pinion is disengaged from the rack and the second resilient means being arranged to restore engagement of the pinion with the rack on rotation of the input drive element beyond said angular position thereof.

In a preferred embodiment, an indicating device in an electrically operated household appliance, in particulara dishwashing machine ora laundry treatment machine, comprises a program control device and a sliding indicator, which is movable in a panel body by way of a gearwith toothed rack and which is arranged behind a panel provided with at least one viewing window at the front side and having markings such as symbols orthe like. The gear comprises an input member, which is arranged concentrically with a shaft of the control device and is mounted in the panel body, an output member which co-operates directlywith this and is mounted parallel ly to the shaft of the control device, and a toothed pinion which is movable into engagement between the output member and the rack.The output member co-operating with the input member sits on the bearing spigot of a rocker (19), while the pinion is arranged displaced on a spigot on the rocker. A spring holds the rocker with the toothed pinion in meshing engagement with the output member and the toothed rack. The pinion, after rundown ofthe program, can be broughtoutof engagement with the rackthrough a heightened tooth, abutment pin, dog orthe like ofthe input member as well as through the rocker, whereby the rack is pushablethrough a restoring spring back into its initial position. The rocker, on a further rotation of the input member and after overcoming the heightened tooth, can be brought by an associated spring into an initial position in which the gear parts again stand in engagement with the rack.

Such an indicating device, which is usable in, for example, a dishwashing machine, a laundering machine and a laundry drier, can be initiatable by way of a rotary knob in the program control device if the device does not start on its own and, during the rundown ofthe program, shows the respective program state and/orthe remaining running time of the program. In that case, the rotary knob serves exclusively for the starting of the program, and the control device after the start actuation takes over the drive of the indicating device. The gear elements and the sliding indicator can return automatically into their initial position after a 3600 rotation of the shaft of the program control device or of the rotary knob, so that damage of the indicating device is not possible also through multiple rotation of the rotary knob in drive sense.On the other hand, a heightened tooth and afeelerfinger co-operating therewith excludes an undesired resetting ofthecontrol device or a lock of the control device itself prevents rotation ofthe rotary knob against the drive sense.

The entraining connection between the rotary knob and a hollow shaft ofthe control device can be by way of a flattened spigot which is disengageable in the construction with a control device startable through a rotary knob, wherebythe panel body can be set onto or removed from the appliance in simple manner. The panel body can therefore be pre-assembled completely, i.e. it can be equipped with the indicating device and tested separately from the appliance. Moreover, appliance design variants and repairs can be carried out more easily.

An embodimentofthe present invention will now be more particularly described byway of example with reference to the accompanying drawings, in which Figure 1 is a perspective view of an electrically operated household appliance embodying the invention, with a panel body atthe front side and an indicating device as well as operating elements; Figure 2 is a vertical section of the panel body with the indicating device; and Figure 3 is a partly broken away front view of a portion ofthe indicating device.

Referring now to the drawings, there is shown a dishwashing machine 1 which at the front side has a control panel, which is constructed as a panel body 2 and at which are mounted a rotary knob 3 as well as operating elements. The body2, in this case arranged on an appliance door4,forms an opaque shield 5 and contains a viewing window 6 atthefront side. A horizontally displaceable toothed rack 7, which carries a sliding indicator8, is guided inthe shield body 2. The indicator 8 appears behind the window 6 during the displacement of the toothed rack and symbols or other markings (not shown), which are associated with the selected program, are arranged on the shield 5.

The knob 3, which is arranged preferably at least partially recessed in the body 2, comprises a cap-shaped part detented with an inner cover part9 insertablefromthe undersideofthe knob. Arranged between the cap-shaped part andthe innercover part is an intermediate piece 10, which carries a rotary spigot 11, which is constructed to be flattened on one side and penetrates the part 9. The piece 10 and the spigot 11 are movable so that axial displacement between the central axis of a hollow actuating shaft 12 of a program control device 13 and the central axis ofthe rotary knob recessed in in the body 2 can be compensatedfor.Adisengageable entraining connection is provided between the spigot 1 and the shaft 12 device 13, which is fastened atthe machine side.

For actuation of the indicating devicethroughthe rotary knob orthe program control device, a gear is provided, which consists of an input member 14 in the form of a pinion which is moulded on the inner cover part 9 of the knob 3, an output part 15, which is constructed as toothed wheel and constantly stands in engagement with the input member, and a toothed pinion 17 which is movable into as well as out of engagement with the toothing 16 of the rack7 and the output member 15. The input member or pinion 14 is mounted concentrically with the shaft 12 ofthe control device 13 and the output member 15 or intermediate wheel is mounted on a bearing spigot 18, arranged axially parallelly to the shaft 12, ofthe body 2.Rotatably arranged on the same bearing spigot 18 is a rocker 19, which is displaced axially parallel ly from the spigot 18 and from the shaft 12 and carries a spigot 20 on which the pinion 17 is rotatably mounted. A spring 22, bearing against a bearing block 21 of the body 2, holds the rocker 19 in an end position in which the pinion 17 is in meshing engagementwith the output member 15 and the toothing 16 ofthe rack 7.

The rocker 19 has a cam follower or feeler finger 23 opposite its end supported by the spring 22 and arranged at the input member 14 but displaced from the toothing thereof is a widened tooth 24, abutment pin, dog orthe like. The body 2 forms a housing 25 forthe rotatable bearing of the knob 3 and a restoring spring 26 is provided between mountings ofthe rack and the body 2 for the pushing the rack 7 with the indicator 8 back into the zero setting.

Figure 1 shows the assembled knob 3 in the body 2, which has the viewing window 6, through which the indicator 8 is visible. Figure 2 shows the construction in section. The knob 3 is rotatable in the shield body 2, yet held undisplaceably in axial direction by hooks 27 of the housing 25.

Injection-moulded onto the knob 3 is the toothed wheel 14, which meshes with the toothed wheel 15 (Figure 3). The wheel 15 sits on the rocker 19, which is mounted coaxially with the wheel 15 on the spigot 18. Mounted on the rocker 19 atthe spigot 20 is the pinion 17, which is in engagement with the toothing 16 ofthe rack 7. The spring 22 presses pinion 17, by way of the rocker 19, againstthetoothing 16 ofthe rack 7. The knob 3 is entrained by way of its spigot 11 through the shaft 12 ofthe control device 13 during the rundown ofthe program and rotates in arrow direction 28, during which the rack is displaced in the direction of arrow 29. The indicator 8 in that case runs away from the shield 5, which is injection-moulded to the body 2.When the rotary knob 3 has rotated through about 340 , the tooth 24 abuts against the feeler finger 23 of the rocker and rotates this about the spigot 18. In the course ofthis movement, the pinion 17 comes out of engagement with the toothing 16 and the rack7 is pushed back into its initial position through the spring 26. On complete rotation of the input member 14 or ofthe rotary knob 3, the tooth 24 again frees the rocker 19 and the spring 22 presses the pinion 17 backintothe toothing 1 6 of the rack 7. By virtue of this arrangement, the entire indicating device is mounted precisely in the body 2 and can be completely assembled and tested independently of the appliance.

In a household appliance which is equipped with a control device able to startwithoutthe aid ofthe rotary knob, the knob can be dispensed with. In that case, the input member 14 in the form of a toothed rim is then not visible from the front side, the member 14 being guided in the body 2 on a part matched to the cover part 9 and couplable with the shaft 12 of the control device 13. The further gear parts and other parts of the afore-described embodimentofthe indicating device are retained.

Claims

1. A domestic appliance provided with a control device to control operation ofthe appliance according to program and with indicating means operable to indicate rundown of such program and comprising a panel with a transparent viewing window, an indicator member connected to a rack and movable between two end positionstotravel across the window and past markings indicative of the rundown of the program, first resilient means to urge the indicator member into one end position thereof associated with the start of the program, a rocker which carries a pinion rotatable about a first axis and which is pivotable about a second axis spaced from the first axis to move the pinion into and out of engagement with the rack for driving the indicator member in direction from said one end position to its other end position, second resilient means to urge the pinion into engagementwiththe rack, an intermediate drive element rotatable about the second axis to drive the pinion, and an input drive element which is rotatable about a third axis by the control device in dependence on rundown of the program to drive the intermediate drive element and which is provided with cam means so co-operable with the rocker during rotation of the input drive element through an angular position associated with the end of the program as to cause the rockerto move the pinion out of engagement with the rack, the first resilient means being arranged to return the indicator member to said one end position when the pinion is disengaged from the rack and the second resilient means being arranged to restore engagement of the pinion with the rack on rotation of the input drive element beyond said angular position thereof.

2. An appliance as claimed in claim 1,wherein the input drive element is rotatable by the control device by way of a rotary knob which is rotatably mounted in the panel and carries the input drive element and which is provided with an axial pin removably engaged in and rotationally drivable by a hollow drive shaft of the control device, the knob being rotatable to actuate the control device.

3. An appliance as claimed in claim 2, wherein the knob comprises an outer part rotatably mounted in housing means of the panel and an inner part connected to the outer part.

4. An appliance as claimed in claim 3, wherein the knob comprises an intermediate part arranged between the inner end outer parts and the axial pin is connected to the intermediate part, the intermediate part being movable radially of the axis of the knobto compensate for any offset of that axis relative to the axis of the drive shaft.

5. An appliance as claimed in either claim 3 or claim 4,wherein the third axis is defined by an axle pin formed integrally with the housing means, and the intermediate drive element comprises a toothed wheel mounted on the axle pin together with the rocker.

6. An appliance as claimed in any one ofthe preceding claims, the cam means comprising an abutment pin, a dog or other projection.

7. An appliance as claimed in claim 6, the input drive element being a toothed wheel and the cam means being arranged on the toothed wheel in a position axially offset from the teeth thereof.

8. An appliance as claimed in any one of the preceding claims, the second resilient means comprising a spring acting between support means atthe panel and one end portion of the rocker, the other end portion of the rocker being constructed as follower co-operable with the cam means.

9. An appliance as claimed in any one ofthe preceding claims, the cam means being so disposed on the input drive element that the element is rotatable through substantially 360' from start of movement of the indicator member from said one end position before passing through and beyond said angular position.

10. An appliance as claimed in claim 1,wherein the input drive element comprises a toothed wheel drivingiy coupled to a drive shaft ofthe control device and arranged behind the panel to be concealed from view at a front side of the appliance.

11. An appliance as claimed in any one ofthe preceding claims, the appliance being one of a clothes washing machine a dishwashing machine.

12. A domestic appliance substantially as hereinbefore described with reference to the accompanying drawings.