GB1565956A - Range-changing device for a time lapse relay - Google Patents

Abstract

A central rotation shaft (28) extends parallel to a shaft of a step-down transmission (55). A changeover knob (9) for switching over the time regions is placed on one end of the rotation shaft. A lengthened gearwheel (64), which extends over the entire length of the step-down transmission, is supported on the other end of the rotation shaft. A number of pinions (63), which engage with the gearwheel but are in different levels, are arranged around the said gearwheel. The shafts (59) on which the pinions are supported such that they can rotate are mounted in a bearing disc (62) which is connected firmly to the central rotation shaft (28). One of the pinions (63) can be selectively engaged with that gearwheel (67) of the transmission which is arranged in the same plane as the relevant pinion, by rotating the changeover knob. Flat sections (58) corresponding to the number of pinions are provided on the bearing disc (62), which sections (58) produce a latching effect in conjunction with a leaf spring, so that one of the pinions is always engaged with one of the gearwheels (67) of the transmission. <IMAGE>

Description

(54) RANGE-CHANGING DEVICE FOR A TIME LAPSE RELAY (71) We, SCHLEICHER GMBH & CO., RELAIS-WERKE KG, a Germany Company of Pichelswerder Strasse 3--5, D--1000 Berlin, 20, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to a device for changing a time range in an electromechanical timing relay, in which a timelapse wheel is actuated by a motor drive by way of reduction gearing after selecting a predetermined time, the various reduction stages of the gearing being able to be engaged separately by way of a range changing knob.

In addition to single time range relays, multiple time range relays have been used in practice to an increasing extent, i.e. relays m which several time ranges may be pre-selected as desired by a switching process, according to suitability, in which ranges, time lapses or response times may be continuously set. In some designs, changing between the various time ranges takes place by way of a shaft provided with a slot on the end face, by means of a screw driver or an actuating member supplied with the timing relay, for example a detachable knob or the like.

In a particularly advantageous known construction, a range-changing knob for the various time ranges is mounted in a so-called "piggy-back" arrangement on the adjusting knob for the time selection within a given time range, which may be actuated without the assistance of a tool and can be removed and replaced by a locking plate if the specifications provided do not allow for range-changing without auxiliary means.

Changing from one time range to another, for example from a time range with a maximum pre-set time of 30 seconds to another with a maximum time adjustment possibility of 3 minutes, takes place in the last analysis by way of the associated actuating member due to the fact that in the drive between the synchronous motor actuating the timing relay and the time-lapse wheel, various stages of the reduction gearing are engaged.

In a known timing relay (Siemens 7 PR 30 514/Z 51 K) this takes place due to the fact that a shaft mounted laterally in a plate, which shaft projects from the front panel of the relay, on the end face and is provided with an actuating slot, can be turned to and fro between two positions. These two positions offset through 900 with respect to each other as regards the actuating slot actually represent a time range of 0 or 3 to 90 and on the other hand of 0 or 0.5 to 15 seconds. For the range-changing process, the shaft is connected to a toothed segment which meshes with a gear wheel, with is held in a non-rotary manner on a shaft, which also supports a double gear wheel once more connected to the latter in a non-rotary manner, which engages with the output pinion of the motor of the timing relay. The first gear wheel, which is provided with teeth only over part of its periphery, simultaneously forms a bearing disc for two pinions meshing with the latter double gear wheel, which pinions are arranged at two different heights, seen axially. These heights of spacings correspond to the spacings between two gear wheels of the reduction gearing, which represent various reduction stages.

Apart from the fact that this known timing relay only offers the possibility of preselecting two different time stages, it also has the drawback of a range-changing control which is not arranged centrally, is moved to and fro between two positions and is difficult to see.

It is an object of the present invention to provide a device for the selection of a time range in an electro-mechanical timing relay in which a plurality of different time ranges may be selected without the direction of rotation of the range changing knob having to be taken into consideration and in particular with the simplest possible construction of the range-changing device itself and with high reliability as regards service and operation.

According to the present invention, there is provided a device for the selection of a time range in an electro-mechanical timing relay in which a time-lapse wheel controlling electrical contacts is rotated by a motor drive by way of reduction gearing after the selection of a predetermined time range reduction stage of the gearing which is engageable selectively by means of a range-changing knob, the device comprising a shaft fixed to the range-changing knob and supporting thereon a loosely journalled coaxial gear wheel which forms part of said reduction gearing and is in mesh with each one of a plurality of pinion wheels spaced circumferentially around the gear wheel on at least one bearing disc secured coaxially on the shaft, whereby a selected pinion wheel can be brought into mesh with a respective further gear in the reduction gearing by rotation of said range-changing knob, and a detent member which can resiliently engage any of a plurality of locating notches or the like on said bearing disc, each of said notches or the like corresponding to a different one of the reduction stages of the gearing.

Advantageous developments and embodiments of this solution of the object will become apparent from the following description.

The arrangement of a plurality of individual pinion wheels for the various reduction stages on a bearing disc connected to the central shaft in a non-rotary manner may be compared with the arrangement of cartridges in a revolver, which leads not only to particularly operationally reliable use of the device, but also to a simple space-saving construction with a simultaneous possibility of central operation. A comparatively large number of reduction stages may be provided on the range-changing device constructed in this way, the particular advantage consisting in that the range-changing operation may be undertaken by rotation of the knob in either direction. For this, it is essential and of significance that in each of the possible reduction stages or pre-set time ranges, the detent locating means of the bearing disc is constructed symmetrically, i.e. allows rotary movement for the range-changing operation to the same extent in both directions.

The central shaft of the device for changing the time range for electromechanical time relays is guided through the time-lapse wheel and adjusting knob for the respective pre-set time so that it is possible to locate the time range-changing knob centrally on the adjusting knob.

The accompanying drawings illustrate one embodiment of the invention by way of example and in conjunction with the following description serve for its further clarification and to emphasise the advantages as a result of the construction chosen: Fig. 1 is a lateral section through an electro-mechanical timing relay with a device for changing a time range constructed according to the invention; and Fig. 2 is a section on line A-A of Fig. 1, seen in the direction of the arrows.

According to the illustration, the timing relay to be operated from a front panel 1 by way of an adjusting knob 10 and a time range-changing knob 9 is surrounded by a housing cover 27, in which all the mechanical and electrical components are located.

The timing relay is driven by a synchronous motor 86 with an output pinion 73, which meshes with a gear wheel 68. The synchronous motor 86 is mounted on a motor plate 80, which is kept at a distance from frame 30. The gear wheel 68 is non-rotatably mounted on a shaft together with part a of the reduction gearing 55, which is made up in the manner illustrated from a plurality of gear wheels 67. The power drive from the synchronous motor 86 travels by way of the pinion 73, the gear wheel 68 and the reduction gearing 55 to a pinion 63, which belongs to a range-changing unit, which in addition to a plurality of further pinions 63 is represented essentially by a double gear wheel 64 and a bearing disc 62.

As shown particularly by the sectional view of Fig. 2 along line A-A of Fig. 1 the individual pinions 63 are arranged on a circle on the bearing disc of the device for range-changing, in which case they have equal spacings not only with respect to the central rotary shaft 28, but also with respect to each other. The teeth of each pinion 63 mesh with the axially extended gear wheel 64 and they are arranged at different heights in the manner shown.

For this, the individual pinions 63 are arranged to rotate freely on shafts 59, which are mounted firstly in the bearing disc 62 and secondly in a second disc located parallel to the latter and at a distance therefrom.

Each height or spacing of a pinion 63 from the bearing disc 62 corresponds to the height of a reduction stage, i.e. to one of the gear wheels 67 of the reduction gearing 55, so that during rotation of the time range-changing knob 9, the pinions 63 may engage respectively one after the other with a different one of the gear wheels 67. The drive from the synchronous motor 86 is thus transmitted in the manner above-described by way of the reduction gearing 55 and the pinion 63 respectively meshing with one of the gear wheels 67 and thus by way of the gear wheel 64 to a gear wheel 71, which is non-rotatably mounted on a shaft 69 which leads to a coupling 50. In the engaged condition, the coupling 50 which may be actuated by an electro-magnet which is not of interest at this point, transmits the motor drive to the pinion 74 which finally meshes with the time-lapse wheel 22 by which the timed switching process may be controlled.

In the embodiment, according to the revolver-like arrangement of the pinions 63 with their bearing shafts 59 on the bearing disc 62, five different time ranges may be pre-selected. The locking of a range position with the teeth of one of the gear wheels 67 of the reduction gearing 55 engaging one of the pinions 63, is achieved by flats 58, which are advantageously provided on the bearing disc 62 and are produced in a simple manner due to the fact that along the circular peripheral surface, circular segments are cut off, and which are in positive engagement with a leaf-spring 60 in the manner shown in Fig. 2. The central shaft 28 and thus the bearing disc 62 are rotated against the action of the spring force of the leaf-spring 60, which is thus deformed and in particular is irrespective of the selected direction of rotation of the shaft 28 and thus of the switching knob 9. In plan view, the leaf-spring 60 is of L-shaped construction and slmply inserted in bearing blocks which are not shown in detail.

Attention is directed to our co-pending application No. 44776/76.

WHAT WE CLAIM IS: 1. A device for the selection of a time range in an electromechanical timing relay in which a time-lapse wheel controlling electrical contacts is rotated by a motor drive by way of reduction gearing after the selection of a predetermined time range reduction stage of the gearing which is engageable selectively by means of a range-changing knob, the device comprising a shaft fixed to the range-changing knob and supporting thereon a loosely journalled coaxial gear wheel which forms part of said reduction gearing and is in mesh with each one of a plurality of pinion wheels spaced circumferentially around the gear wheel on at least one bearing disc secured coaxially on the shaft, whereby a selected pinion wheel can be brought into mesh with a respective further gear in the reduction gearing by rotation of said range-changing knob, and a detent member which can resiliently engage any of a plurality of locating notches or the like on said bearing disc, each of said notches or the like corresponding to a different one of the reduction stages of the gearing.

2. A device as claimed in Claim 1, in which the notches or the like are provided along the peripheral edge of the bearing disc and are of symmetrical shape.

3. A device as claimed in Claim 2, in which the notches or the like are flats formed by cut-off segments of the bearing disc.

4. A device as claimed in any of Claims 1 to 3, in which a selected one of the notches or the like is engaged by a leaf-spring which forms a resilient detent member.

5. A device for the selection of a time range in an electromechanical timing relay, substantially as hereinbefore described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. the gear wheels 67 and thus by way of the gear wheel 64 to a gear wheel 71, which is non-rotatably mounted on a shaft 69 which leads to a coupling 50. In the engaged condition, the coupling 50 which may be actuated by an electro-magnet which is not of interest at this point, transmits the motor drive to the pinion 74 which finally meshes with the time-lapse wheel 22 by which the timed switching process may be controlled. In the embodiment, according to the revolver-like arrangement of the pinions 63 with their bearing shafts 59 on the bearing disc 62, five different time ranges may be pre-selected. The locking of a range position with the teeth of one of the gear wheels 67 of the reduction gearing 55 engaging one of the pinions 63, is achieved by flats 58, which are advantageously provided on the bearing disc 62 and are produced in a simple manner due to the fact that along the circular peripheral surface, circular segments are cut off, and which are in positive engagement with a leaf-spring 60 in the manner shown in Fig. 2. The central shaft 28 and thus the bearing disc 62 are rotated against the action of the spring force of the leaf-spring 60, which is thus deformed and in particular is irrespective of the selected direction of rotation of the shaft 28 and thus of the switching knob 9. In plan view, the leaf-spring 60 is of L-shaped construction and slmply inserted in bearing blocks which are not shown in detail. Attention is directed to our co-pending application No. 44776/76. WHAT WE CLAIM IS:

1. A device for the selection of a time range in an electromechanical timing relay in which a time-lapse wheel controlling electrical contacts is rotated by a motor drive by way of reduction gearing after the selection of a predetermined time range reduction stage of the gearing which is engageable selectively by means of a range-changing knob, the device comprising a shaft fixed to the range-changing knob and supporting thereon a loosely journalled coaxial gear wheel which forms part of said reduction gearing and is in mesh with each one of a plurality of pinion wheels spaced circumferentially around the gear wheel on at least one bearing disc secured coaxially on the shaft, whereby a selected pinion wheel can be brought into mesh with a respective further gear in the reduction gearing by rotation of said range-changing knob, and a detent member which can resiliently engage any of a plurality of locating notches or the like on said bearing disc, each of said notches or the like corresponding to a different one of the reduction stages of the gearing.

2. A device as claimed in Claim 1, in which the notches or the like are provided along the peripheral edge of the bearing disc and are of symmetrical shape.

3. A device as claimed in Claim 2, in which the notches or the like are flats formed by cut-off segments of the bearing disc.

4. A device as claimed in any of Claims 1 to 3, in which a selected one of the notches or the like is engaged by a leaf-spring which forms a resilient detent member.

5. A device for the selection of a time range in an electromechanical timing relay, substantially as hereinbefore described with reference to the accompanying drawing.