GB2242071A

GB2242071A - A time switch

Info

Publication number: GB2242071A
Application number: GB9104028A
Authority: GB
Inventors: Peter Schonhardt
Original assignee: Graesslin GmbH; Graesslin KG
Current assignee: Graesslin GmbH; Graesslin KG
Priority date: 1990-02-26
Filing date: 1991-02-26
Publication date: 1991-09-18
Anticipated expiration: 2011-02-26
Also published as: DE4104630C2; GB9104028D0; DE4104630A1; GB2242071B; DE9002256U1

Abstract

An electromechanical time switch comprises a stationary programming device which is composed of individual switching elements (7) arranged in a circular array and selectively movable between operative and inoperative positions, a sun gear (1) driving a planet wheel (2) mounted on a pivotable switching lever (3) for actuating a fixed electrical switch (14), a ring gear (5) in driving engagement with the planet wheel (2), a sensing lover (6), which senses the switching elements (7) and which is pivotably and eccentrically mounted at (16) to the ring gear (5) and at (17) to a further gear (10), (not shown) the arrangement being such that when the sensing lever (6) abuts against and comes to a halt against a switching element (7) arranged in an operative position, the ring gear (5) is held stationary and the first planet wheel (2) continues to be driven so that the switching lever (3) is pivoted against the action of a spring force (15) in order to actuate the switch (14), and when the switching lever (3) has come to a halt against the actuated switch (14), by virtue of its engagement with the rotating further gear (10), the sensing ever (6) is pivoted radially away from its abutment against the switching element (7). <IMAGE>

Description

A TIME SWITCH The invention relates to an electromechanical time switch comprising a stationary programming device which is composed of individual switching elements arranged closely adjacent to one another and In the form of a circular ring, and the switching elements of which, which are programmed in accordance with a switching programme, are sensed by a switching device which rotates in time-keeping fashion, in order to actuate a stationary electrical switch.

German Patent 910 081 discloses a time switch in which the switching times are determined by switch pins which are inserted In fixed fashion into apertures provided in a circular array at the periphery of the dial face. These switch pins, which are Inserted in accordance with a switching programme, are sensed by a switching wheel which rotates in time-keeping fashion and which actuates a rotating electrical switch, which is supplied with current via a likewise rotating contact disc, provided with slip rings, and via fixed brush springs.

This time switch involves the serious disadvantage that not only is the electrical contact technically elaborate and complicated, but also the current supply to the rotating contact is inadequately dimensioned in respect of the current density required for the electrical power which is to be transmitted in such time switches, and the mechanical driving torque for the contact disc. This electrical contact arrangement is also uneconomical to produce.

In another electromechanical time switch comprising programmable switch pins, known from German Patent 910 081, the electrical contact arrangement is stationary. A rotating mechanical switching device serves to sense the stationary switch pins and by means of a switching wheel, which engages with the switch pins, actuates a rotating lever mechanism which In turn actuates the electrical contact arrangement.

Although In the case of this time switch it is possible for the switch to be adequately dimensioned in terms of electrical supply, the mechanical switching device which rotates in time-keeping fashion is technically elaborate and complicated, and because of the relatively large sensing radius of the switching wheel, requires a large amount of space.

The aim of the invention is to provide a time switch with a stationary programming device of the type described in the introduction wherein the rotating, mechanical switching device is technically simple, reliable in function and economical to produce.

According to the present invention, an electromechanical time switch comprises a stationary programming device which Is composed of switching elements which are arranged in a circular array and are selectively movable between operative and inoperative positions, and the switching elements in their operative positions are sensed by a switching device which rotates in time-keeping fashion, for the actuation of a stationary electrical switch, wherein the switching device is provided with a planetary gear system, wherein a sun gear drives a first planet wheel in time-keeping fashion, the first planet wheel being mounted on a pivotable switching lever for the actuation of the electrical switch, the first planet wheel being fixed to a pinion which is in engagement with a first gear, to which a sensing lever is eccentrically and pivotably mounted, the sensing lever being also eccentrically pivotally mounted to a third gear coaxial with the first gear and connected to the sun gear via a second planet wheel so as to be driven at the same speed as the first gear, which rotates in time-keeping fashion, in such manner that when the sensing lever abuts against a switching element in its operative position, the first planet wheel continues to be driven and the switching lever is pivoted against the action of a spring force in order to actuate the switch, and when the switching lever has come to a halt against the actuated switch, under the influence of the planetary gear system the sensing lever, by virtue of its mounting on the third gear, is pivoted out of engagement with the switching element.

An embodiment of the invention will now be explained in detail with reference to the drawings, in which: Figure 1 is a diagram of an arrangement of the mechanical switching device; Figure 2 is-a side view of the device illustrated in Figure 1; Figure 3 is an internal view of a time switch comprising a new switching device; Figure 4 is a plan view of the base plate construction of the switching device of the time switch illustrated in Figure 3 with the sensing device removed; Figure 5 is a front view of the sensing device; and Figure 6 is a front view of the time switch illustrated in Figure 3.

The mechanical switching device illustrated in Figure 1 and 2 basically comprises a planetary gear system which is driven in time-keeping fashion by a sun gear 1. The sun gear 1 is in engagement with the drive device of the time switch, but this engagement has not been shown in detail. The sun gear 1 drives a first planet wheel 2 which is rotatably mounted on a switching lever 3. The switching lever 3 is itself pivotably mounted at one end about the axis of sun gear 1, in order to actuate an electrical switch 14 by engagement of its free end.

The first planet wheel 2 is coaxially coupled to a pinion 4. The first planet wheel 2 and the pinion 4 rotate at the same rotational speed. The pinion 4 is in engagement with a ring gear 5 which is mounted coaxially with the sun gear 1, and a sensing lever 6 is eccentrically and pivotably mounted on the ring gear 5. The sensing lever senses the programmed, rib-shaped switching pins 7 of the stationary programming device which is arranged in a circular formation coaxially with the ring gear 5 and the sun gear 1. The programming device comprises a plurality of pins 7 arranged in a circular array, each pin being movable radially from an outer, inoperative position to an inner, operative position wherein the pin 7 obstructs the path of a sensing lug 13 forming part of the sensing lever 6.This sensing lever 6 is also provided with a coupling pin 9 in the region of its free end 8, which coupling pin 9 extends through the ring gear 5 and is eccentrically rotatably engaged with a third gear 10 which is likewise arranged coaxially with the ring gear 5 and the sun gear 1, and which is likewise driven in time-keeping fashion by the drive device of the time switch via a gear reduction unit comprising a second planet wheel 11 and a drive gear 12.

If the sensing lug 13 arranged on one side of the sensing lever 6 now abuts against a switching element 7 positioned in an operative position in accordance with a switching programme, the sensing lug 13 of the sensing lever 6, and thus also the ring gear 5, are momentarily halted. The time-keeping drive device continues to drive the first planet wheel 2 continuously so that the pinion 4 rolls over the stationary ring gear 5. As a result of this continued rotation of the first planet wheel 2 and the pinion 4, which are mounted on the switching lever 3, the switching lever 3 is pivoted and the stationary electrical switch 14 is thereby actuated.

In a further sequence of the drive movement, and with the first planet wheel 2 also now stationary, continued rotation of the third gear 10, driven by the second planet wheel 11, causes the pin 9 to move round the axis of the sun gear 1 and ring gear 5, and the sensing lever 3 is thus rotated about the pivot 16 in a clockwise direction as seen in Figure 1. This causes the sensing lug 13 to be moved radially outwardly so that the sensing lug 13 can move past the respective switching element 7. As soon as the sensing lug 13 has passed the switching element 7, the switching lever 3 snaps back into its starting position, in particular under the influence of a spring 15, and the switch 14 is returned to its original state.

The radial relative movement of the sensing lug 13 of the sensing lever 6 is achieved by the radially differing eccentricity of the bearing points 16 and 17 df the sensing-lever 6, on the one hand on the ring gear 5 and on the other hand on the third gear 10. A dial 36 indicating the time of day and comprising a minutes hand and an hours hand is provided to show the current time for setting purposes.

Figure 3 illustrates the spatial Integration of the switching device in a time switch. The switching device Is arranged and mounted to a base plate 18 which will be described in further detail in this specific embodiment and in the arrangement in Figure 4. A minutes hand disc 19 and an hours hand ring 20 with an hours hand mark 21 enable the time of day to be read on a dial face 22 illustrated in Figure 5. A socket 23 is integrated into the time switch, and a plug which is not illustrated In detail in the individual figures may be arranged coaxially therewith on the rear side. This illustrated time switch Is a so-called 'plug and socket time switch'. The supply of power from the plug to the socket 23 being controlled by the programme controlled switch. Fixing apertures 24 are provided on the front side 25 of the housing illustrated in Figure 6, and the sensing device 26 with the sensing lever 6 are also shown.

The switching device arranged in the time switch shown in Figure 3 differs partially from the construction of the switching device illustrated in Figure 1 in respect of the required spatial design and dimensioning of the individual components, although the reference numerals for corresponding individual components have been substantially retained in the following description of Figures 4 and 5.

The gear elements illustrated in Figure 4, the sun gear 1 and the drive gear 12, are driven so as to rotate in time-keeping fashion. The sun gear 1 is in engagement with the first planet wheel 2 which is arranged and mounted on the pivotable switching lever 3.

The switching lever 3 is pivotally mounted at the centre 27 of a base plate 18. A rib 28 of the switching lever extends through an opening 29 in the base plate 18, to act on an electrical switch which has not been shown in detail here, and which is arranged behind the base plate 18.

The first planet wheel 2 is in engagement with an internally,.

toothed ring gear 5 which is. mbuntedcoaxially with the centre~ Hof the base-plate. The sensing lever 6 with the sensing-lug 13 is also pivotably mounted on the ring gear 5. In addition a fork-shaped groove 30 arranged on one side of the sensing lever 6 is in engagement with a bearing pin 9 which is arranged eccentrically on the third gear 10 which is likewise mounted coaxially with the centre 27 of the base plate, directly behind the ring gear 5. This third gear 10 is in engagement with the drive gearl2, which rotates in time-keeping fashion, on the drive shaft 31 dn which the sun gear 1 is mounted.Switching elements 7 of the programming device are provided in a stationary array, coaxial with the centre 27 of the base plate, and for programming are arranged closely adjacent to one another and in particular so as to be radially movable and in the form of a circular ring, and which can be seen in detail in Figure 6, which will be described in the following.

In Figure 6, 32 designates the front part of the housing with the programming device which is arranged here and which comprises the switching elements 7. A 24-hour scale 33 is fixed In relation to the programming device, and a dial face 22 for the time of day has a minutes hand disc 19 and an hours hand ring 20. A socket 23, the circuit of which is switched by the switching device in time-controlled fashion, is also connected to a manual switch 34 for manual actuation of the built-in electrical switch 14, overriding the programmed control cycle.

It is within the scope of the invention that, in place of the illustrated and described switching elements of the programming device, switching elements in another design and with a different manual programming operation can be used.

It is also provided that this new switching device can also be used expediently and advantageously in time switch designs other than the described, so-called plug and socket time switch.

Claims

1. An electromechanical time switch comprising a stationary programming device which is composed of switching elements which are arranged in a circular array and are selectively movable between operative and inoperative positions and the switching elements in their operative positions, are sensed by a switching device which rotates in time-keeping fashion, for the actuation of a stationary electrical switch, wherein the switching device is provided with a planetary gear system, wherein a sun gear drives a first planet wheel in time-keeping fashion, the first planet wheel being mounted on a pivotable switching lever for the actuation of the electrical switch, the first planet wheel being fixed to a pinion which Is in engagement with a first gear, to which a sensing lever is eccentrically and pivotably mounted, the sensing lever being also eccentrically pivotally mounted to a third gear coaxial with the first gear and connected to the sun gear via a second planet wheel so as to be driven at the same speed as the first gear, which rotates in time-keeping fashion, in such manner that when the sensing lever abuts against a switching element in its operative position, the first planet wheel continues to be driven and the switching lever is pivoted against the action of a spring force in order to actuate the switch, and when the switching lever has come to a halt against the actuated switch, under the influence of the planetary gear system the sensing lever, by virtue of its mounting on the third gear, is pivoted out of engagement with the switching element.

2. A time switch as claimed In Claim 1, wherein the first and third gears are arranged coaxially with one another and that the first gear is designed as an internally toothed wheel.

3. A time switch as claimed in Claim 1 or Claim 2, wherein the switching lever is mounted to pivot about an axis coaxial with the axes of the first and third gears.

4. A time switch as claimed in any of Claims 1 to 3, wherein the sensing lever, which Is eccentrically In engagement with the first and third gears, is provided with a sensing lug extending laterally from the lever.

5. A time switch as claimed in Claim 4, wherein the ratio between the radial distances of the two eccentric bearings of the sensing lever from the axis of the first and third gears is approximately 1 : 1.52.

6. A time switch as claimed in Claims 1 to 5, wherein the switching elements are mounted so as to be radially movable between their operative and inoperative positions for the purpose of their programming.

7. A time switch as claimed in Claims 1 to 6, wherein a dial face which displays the time of day and which comprises a minutes indicator and an hours indicator is arranged coaxially with the switching device.

8. A time switch as claimed in Claim 7, wherein the hours indicator is ring-shaped.

9. A time switch as claimed in Claims 1 to 8, wherein the switching device is arranged in a housing with an integrated socket and a plug arranged in particular coaxially with the socket.