EP0070934A1 - Variable electrical resistance device - Google Patents
Variable electrical resistance device Download PDFInfo
- Publication number
- EP0070934A1 EP0070934A1 EP81303475A EP81303475A EP0070934A1 EP 0070934 A1 EP0070934 A1 EP 0070934A1 EP 81303475 A EP81303475 A EP 81303475A EP 81303475 A EP81303475 A EP 81303475A EP 0070934 A1 EP0070934 A1 EP 0070934A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- housing
- support
- secured
- shaft
- spindle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C1/00—Details
- H01C1/01—Mounting; Supporting
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C10/00—Adjustable resistors
- H01C10/14—Adjustable resistors adjustable by auxiliary driving means
Definitions
- This invention relates to a rotary variable electrical resistance device and more particularly to a variable resistance device having a rotatable operating spindle adapted to be secured to a rotatable shaft whose angular rotation is to be followed by the variable resistance device, the device having a novel means of mounting and location with respect to a support such that it is able to accommodate misalignment or bending of the shaft or a degree of axial and radial play in the shaft.
- Rotary variable electrical resistance devices eg. potentiometers
- Such a device typically comprises a housing containing an arcuate element of electrical resistance material adapted to be traversed by a wiper of electrically conductive material, the wiper being operated by a rotatable spindle which is supported on bearings in the housing. Adjustment of the setting of the device is effected by rotating part of the spindle which protrudes from the housing. It has hitherto been common practice to mount a variable resistance device with its housing rigidly secured to a support which may, for example, be a rigid plate having a hole through which the operating spindle of the device passes.
- the present invention provides a rotary variable electrical resistance device comprising: a housing; a spindle secured in and arranged for rotation in said housing and adapted to adjust the setting of said device by causing a wiper of electrically conductive material to traverse an electrical resistance element supported on or in said housing, said spindle being adapted to be substantially rigidly secured to the end of a rotatably supported shaft, on a common axis with said shaft, whereby said spindle is rotatable with said shaft and such that said shaft substantially supports said device; means cooperating between said housing and a support to restrain said housing from rotation about the axis of said spindle when said spindle is caused to be rotated by said shaft, said means also being arranged such that said device is displaceable to follow longitudinal and/or lateral displacement of said end of said shaft.
- said means cooperating between said housing and support comprises a rigid member having a portion thereof adapted to be secured to said support and__- a further portion adapted to engage a recess or__ g pening in said housing or in a part secured to or extending from said housing.
- said means cooperating between said housing and support comprises a rigid member having a portion thereof adapted to be secured to said housing rather than said support and a further portion adapted to engage a recess or opening in said support rather than in said housing or in a part secured to or extending from said support.
- Backlash resulting from clearance between said member and said recess or opening may be avoided or minimised by providing one or more springs or other suitably resilient material between said member and said housing or said support or said part secured thereto.
- said rigid member comprises a pin or bolt.
- the said pin or bolt may have a head for engaging said recess or opening; said pin or bolt or said head may be radiused to produce a substantially barrel-shape whereby variations in the angle at which said pin or bolt enters said recess or opening can be accommodated without said pin, bolt or head becoming jammed in said recess or opening.
- the said part secured to or extending from said housing or said support suitably comprises a lug, flange, plate or disc having a hole or a recess therein for accommodating said rigid member.
- One or more further lugs or flanges may be provided secured to or extending from said housing and each provided with a hole therein through which a screw or bolt with a head may be passed and secured to said support, said head of said screw or bolt being arranged to be clear of said lug or flange to permit displacement of said device to follow said longitudinal displacement of said end of said shaft, whilst providing a limitation for this displacement of the device.
- the plurality of lugs or flanges may be replaced by a single plate, secured to and extending from said device and provided with holes or recesses for accommodating said screws, bolts or pins.
- said means cooperating between said housing and support may comprise a spring blade having one end secured to said support and the other end secured to said housing said spring blade being deflectable to permit said device to be displaced to follow lateral displacement of said end of said shaft.
- Said one or said other end of said spring blade may optionally be slideably secured to said support or said housing respectively, eg. by location in a slot or groove in said support or said housing, to permit said device to be displaced to follow longitudinal displacement of said end of said shaft.
- said means cooperating between said housing and support may comprise a band encircling and spaced from said housing and secured to said support, a suitably resilient material being provided between said band and said housing to permit displacement of said device to follow said displacement of said shaft.
- the said band may comprise a metal or plastics material; said resilient material suitably comprises a rubber, eg. silicone rubber.
- the means cooperating between the housing and support comprises a pin extending from a disc-shaped member adapted to be clamped at its periphery to said support by means of a ring-shaped member, said pin being arranged for location in an aperture provided in a flange member secured to the housing of the resistance device concentrically with said spindle, said disc shaped member and said support having an opening therein through which said spindle may pass, said flange member being shaped for loc-ation within said ring shaped member such that clearance is provided between said flange member and said ring shaped member to permit said device to be displaced to follow said longitudinal and/or lateral displacement of said end of said shaft, the location of said pin in said aperture in said flange member serving to restrain said housing from rotation about said axis of said spindle.
- said pin instead of said pin being provided on the disc shaped member it may be provided extending from the flange member and arranged to be located either in an aperture provided in the disc shaped member or, if the disc shaped member is eliminated, in an aperture provided in said support.
- said ring shaped member is secured to said support by means of screws or bolts.
- a rotary variable electrical resistance device eg. a potentiometer
- a housing 1 of metal or rigid plastics material containing an arcuate element of electrical resistance material (not shown) adapted to be traversed by a wiper of electrically conductive material (not shown), the wiper being operated by a rotatable spindle 2 arranged for rotation in bearings 3 and 4 in the housing 1, to adjust the setting of the device.
- a rotatable spindle 2 arranged for rotation in bearings 3 and 4 in the housing 1, to adjust the setting of the device.
- the spindle 2 is rigidly secured, by means of a solid coupling 5, to the end of a rotatably supported shaft 6 whose angular rotation is to be followed by the variable resistance device.
- Shaft 6 may comprise, for example, a throttle control shaft of an internal combustion engine in a motor vehicle, the setting of the variable resistance device being required to be changed by rotation of the throttle control shaft, for effecting control functions in the operation of the engine.
- the coupled spindle 2 and shaft 6 have a common axis 7.
- the shaft 6 supports the variable resistance device.
- a rigid member in the form of a pin 8 is secured at one end into a fixed support 9 which suitably comprises a metal plate or bracket.
- the end of the pin 8 is suitably threaded and engages a similarly threaded hole in the support 9.
- the housing 1 of the variable resistance device is provided with a lug or flange 10 extending therefrom and having a hole 11 through it.
- the variable resistance device is arranged such that the spindle 2 passes through a hole 12 provided in the support 9 and such that the pin 8 locates in the hole in the lug or flange 10.
- This simple arrangement is advantageous since it allows the variable resistance device to be displaced to follow any longitudinal displacement (ie. in the direction indicated by arrows A, B) or lateral displacement (ie. in the direction indicated by arrows C, D and E, F) of the end of shaft 6 which is coupled to the spindle 2, such displacement of the shaft taking place as a result of play in bearings which support it.
- the arrangement also allows the variable resistance device to tilt to accommodate a situation where the shaft 6 is not perpendicular to the support 9, or as a result of the shaft 6 being bent.
- a suitably resilient material such as a spring or rubber (eg. silicone rubber) can be applied between the pin and sides of the hole to take up the clearance whilst permitting the necessary displacement to occur.
- pin 8 is shown in Figures 1 and 2 as having parallel sides, it may be advantageous for the pin to be formed of a barrel shape, thereby minimising risk of the pin jamming in the hole 11 when the housing 1 of the device is caused to be tilted.
- One or more further lugs or flanges 13, similar to lug or flange 10 may be provided, having a hole 14 therein.
- Such lugs or flanges 10, 14 are often already provided during manufacture of the device and hitherto intended for use in rigidly securing the device to a support.
- a screw 15 with a head 16 is passed through hole 14 in lug 13 and screwed into a hole provided in support 9.
- the head 16 of the screw is arranged to be sufficiently clear of the lug 13 to permit the required degree of displacement of the device, whilst serving to prevent the spindle 2 from becoming decoupled from the shaft 6, eg. in event of the arrangement being utilised in conditions of severe vibration. It would be preferable to provide at least two further lugs 13 with screws 15, for this purpose.
- a pin with a head may be substituted, the head engaging the hole 11 in lug 10.
- the head of the pin is radiused to provide a barrel shape to prevent the head jamming in the hole when the housing 1 is caused to be tilted.
- variable resistance device it may be necessary, for some applications, to preset the variable resistance device to allow a particular phasing between the device and the shaft coupled thereto. This may be achieved by providing a slot in the support 9 and providing one or more lock nuts on the end of the pin 8. Thus, with the lock nuts slack, the housing 1 of the device is rotated, the pin 8 being moved in the slot in support 9 during this rotation. When a desired setting of the device is attained, the pin is locked in place in the support 9 by means of the lock nuts.
- the housing of the device can be mounted on a sub-plate such that it can be rotated to a required position on the sub-plate and then clamped, a hole or recess being provided in the sub-plate into which pin 8 locates, operation being otherwise the same as described with reference to Figures 1 and 2.
- the pin 8 could be secured to lug or flange 10 or directly to the face of the housing of the device and be arranged to be located i ' n a hole provided in the support 9.
- a disc or plate (not shown) could be clamped to the support and provided with an aperture for location by the pin, thus obviating the need to provide an aperture in the support for this purpose.
- This arrangement also permits a predetermined orientation of the device with respect to the support to be achieved which is valuable for phasing purposes.
- a flat spring blade could be substituted which would be secured at one end to the support 9 and at the other end to the side of the housing 1, lug 10 being unnecessary in such an embodiment.
- This arrangement would permit lateral displacements of the end of shaft 6 to be accommodated, but in the case where longitudinal displacements of the shaft are also required to be accommodated, the end of the spring blade could be slideably secured in a slot or groove in the side of housing 1 or in the support 9.
- variable resistance devices could be provided arranged in ganged form on a common spindle axis and each provided with the means restraining the housing from rotation whilst permitting displacement to follow displacement of a shaft coupled to a spindle at one end of the ganged assembly.
- each of the ganged devices is provided with a lug or flange, as denoted by reference numeral 10 in Figures 1 and 2, then a single pin 8, extended to pass through the holes in the lugs of all the devices, could be used to allow displacement .of the assembly when displacement of the end of the shaft coupled thereto occurs.
- a rotary variable electrical resistance device eg. a potentiometer
- a rotatable spindle 22 extends from the housing for adjusting the setting of the device, spindle 22 being intended to be rigidly coupled to the end of a rotatably supported shaft (such as the shaft 6 shown in Figures 1 and 2) whose angular rotation is to be followed by the variable resistance device.
- a disc shaped member 23 is arranged to be clamped at its periphery to a support 24 by means of a stepped ring shaped member 25, using screws 26 for securement of the member 25 to the support 24.
- a pin 27 extends from the disc shaped member 23 for location in an aperture 28 provided in a circular flange member 29 having a hole through its centre and secured to the housing 21 of the device, concentrically with the spindle 22, by means of nut 30.
- the disc shaped member 23 and support 24 each have a hole therein through which the spindle 22 may pass.
- the flange member 29 is shaped for location within the stepped ring shaped member 25 such that clearance is provided at region 31 between the flange member 29 and ring shaped member 25 to permit the device 21, 22 to be displaced to follow any longitudial and/or lateral displacement of a shaft secured to the spindle 22.
- the pin 27, located in aperture 28 in the flange member 29, restrains the housing 21 from rotation about the axis of the spindle 22 when the latter is rotated.
- pin 27 may be provided on the disc shaped member 23 instead of pin 27 being provided on the disc shaped member 23, it may be provided extending from the flange member 29 and arranged to be located in an aperture provided in the disc shaped member 23. With this arrangement, the disc shaped member 23 may be eliminated if desired and the pin located in an aperture provided in the support 24. In this latter case the ring shaped member 25 would be secured to the support 24 without the intermediary of the disc shaped member 23.
- a further advantage of the present invention is particularly evident where a variable resistance device is operated in conditions where mechanical vibration exists.
- a device of the prior art is rigidly mounted and coupled to an operating shaft, such vibration sometimes results in what is known in the art as 'dither'.
- a small amount of slackness or resilience in the coupling between the housing of the device and support advantageously attenuates the effect of such vibrations and reduces the effect of 'dither' wear on the resistance track.
Abstract
Description
- This invention relates to a rotary variable electrical resistance device and more particularly to a variable resistance device having a rotatable operating spindle adapted to be secured to a rotatable shaft whose angular rotation is to be followed by the variable resistance device, the device having a novel means of mounting and location with respect to a support such that it is able to accommodate misalignment or bending of the shaft or a degree of axial and radial play in the shaft.
- Rotary variable electrical resistance devices,_ eg. potentiometers, are well known in the art. Such a device typically comprises a housing containing an arcuate element of electrical resistance material adapted to be traversed by a wiper of electrically conductive material, the wiper being operated by a rotatable spindle which is supported on bearings in the housing. Adjustment of the setting of the device is effected by rotating part of the spindle which protrudes from the housing. It has hitherto been common practice to mount a variable resistance device with its housing rigidly secured to a support which may, for example, be a rigid plate having a hole through which the operating spindle of the device passes.
- - It is sometimes required to couple the spindle of a variable resistance device to an operating shaft in order to provide an extension to the spindle or to monitor the degree of rotation of such a shaft. Problems exist in accurately aligning the shaft and spindle and also the shaft may not be absolutely straight. The shaft may also be mounted in such a way that it can exhibit a significant degree of axial and radial play. If a solid coupling is used between the shaft and spindle with any of these conditions existing, then the bearings of the spindle in the housing of the device may be subjected to excessive forces, resulting in damage to the device. Variations in torque in the shaft/spindle assembly may also occur during rotation in these conditions.
- It has previously been proposed to deal with this problem by coupling the shaft and the spindle of the device by means of a flexible coupling member. Such a flexible coupling is expensive and often bulky to the extent that insufficient space is available for it to be used in some applications.
- The present invention provides a rotary variable electrical resistance device comprising: a housing; a spindle secured in and arranged for rotation in said housing and adapted to adjust the setting of said device by causing a wiper of electrically conductive material to traverse an electrical resistance element supported on or in said housing, said spindle being adapted to be substantially rigidly secured to the end of a rotatably supported shaft, on a common axis with said shaft, whereby said spindle is rotatable with said shaft and such that said shaft substantially supports said device; means cooperating between said housing and a support to restrain said housing from rotation about the axis of said spindle when said spindle is caused to be rotated by said shaft, said means also being arranged such that said device is displaceable to follow longitudinal and/or lateral displacement of said end of said shaft.
- In one embodiment, said means cooperating between said housing and support comprises a rigid member having a portion thereof adapted to be secured to said support and__- a further portion adapted to engage a recess or__gpening in said housing or in a part secured to or extending from said housing. In a modification of this embodiment, said means cooperating between said housing and support comprises a rigid member having a portion thereof adapted to be secured to said housing rather than said support and a further portion adapted to engage a recess or opening in said support rather than in said housing or in a part secured to or extending from said support. Backlash resulting from clearance between said member and said recess or opening may be avoided or minimised by providing one or more springs or other suitably resilient material between said member and said housing or said support or said part secured thereto.
- Preferably said rigid member comprises a pin or bolt. The said pin or bolt may have a head for engaging said recess or opening; said pin or bolt or said head may be radiused to produce a substantially barrel-shape whereby variations in the angle at which said pin or bolt enters said recess or opening can be accommodated without said pin, bolt or head becoming jammed in said recess or opening.
- The said part secured to or extending from said housing or said support suitably comprises a lug, flange, plate or disc having a hole or a recess therein for accommodating said rigid member.
- One or more further lugs or flanges may be provided secured to or extending from said housing and each provided with a hole therein through which a screw or bolt with a head may be passed and secured to said support, said head of said screw or bolt being arranged to be clear of said lug or flange to permit displacement of said device to follow said longitudinal displacement of said end of said shaft, whilst providing a limitation for this displacement of the device.
- In a modification of the above arrangement, the plurality of lugs or flanges may be replaced by a single plate, secured to and extending from said device and provided with holes or recesses for accommodating said screws, bolts or pins.
- In an alternative embodiment, said means cooperating between said housing and support may comprise a spring blade having one end secured to said support and the other end secured to said housing said spring blade being deflectable to permit said device to be displaced to follow lateral displacement of said end of said shaft. Said one or said other end of said spring blade may optionally be slideably secured to said support or said housing respectively, eg. by location in a slot or groove in said support or said housing, to permit said device to be displaced to follow longitudinal displacement of said end of said shaft.
- In a further embodiment, said means cooperating between said housing and support may comprise a band encircling and spaced from said housing and secured to said support, a suitably resilient material being provided between said band and said housing to permit displacement of said device to follow said displacement of said shaft.
- The said band may comprise a metal or plastics material; said resilient material suitably comprises a rubber, eg. silicone rubber.
- In a still further embodiment, the means cooperating between the housing and support comprises a pin extending from a disc-shaped member adapted to be clamped at its periphery to said support by means of a ring-shaped member, said pin being arranged for location in an aperture provided in a flange member secured to the housing of the resistance device concentrically with said spindle, said disc shaped member and said support having an opening therein through which said spindle may pass, said flange member being shaped for loc-ation within said ring shaped member such that clearance is provided between said flange member and said ring shaped member to permit said device to be displaced to follow said longitudinal and/or lateral displacement of said end of said shaft, the location of said pin in said aperture in said flange member serving to restrain said housing from rotation about said axis of said spindle.
- In a modification of this still further embodiment, instead of said pin being provided on the disc shaped member it may be provided extending from the flange member and arranged to be located either in an aperture provided in the disc shaped member or, if the disc shaped member is eliminated, in an aperture provided in said support.
- Suitably said ring shaped member is secured to said support by means of screws or bolts.
- The invention is now described by way of example with reference to the accompanying drawings in which:
- , Figure 1 shows a perspective view of an embodiment of a rotary variable resistance device according to the invention;
- Figure 2 shows a section through the embodiment of Figure 1;
- Figure 3 shows a part-sectioned exploded view of an alternative embodiment of a rotary variable resistance device according to the invention;
- Figure 4 shows an assembled view of the embodiment of Figure 3.
- Referring to Figures 1 and 2, a rotary variable electrical resistance device, eg. a potentiometer, is constructed comprising a
housing 1 of metal or rigid plastics material containing an arcuate element of electrical resistance material (not shown) adapted to be traversed by a wiper of electrically conductive material (not shown), the wiper being operated by arotatable spindle 2 arranged for rotation inbearings 3 and 4 in thehousing 1, to adjust the setting of the device. Such an arrangement of a housing, arcuate element, wiper and spindle is very well known in variable resistance device technology. Thespindle 2 is rigidly secured, by means of asolid coupling 5, to the end of a rotatably supportedshaft 6 whose angular rotation is to be followed by the variable resistance device.Shaft 6 may comprise, for example, a throttle control shaft of an internal combustion engine in a motor vehicle, the setting of the variable resistance device being required to be changed by rotation of the throttle control shaft, for effecting control functions in the operation of the engine. The coupledspindle 2 andshaft 6 have a common axis 7. Theshaft 6 supports the variable resistance device. - In order to allow the setting of the device to be altered as
shaft 6 is rotated, it is necessary to provide means to prevent rotation of thehousing 1. A rigid member in the form of apin 8 is secured at one end into afixed support 9 which suitably comprises a metal plate or bracket. The end of thepin 8 is suitably threaded and engages a similarly threaded hole in thesupport 9. Thehousing 1 of the variable resistance device is provided with a lug orflange 10 extending therefrom and having ahole 11 through it. The variable resistance device is arranged such that thespindle 2 passes through ahole 12 provided in thesupport 9 and such that thepin 8 locates in the hole in the lug orflange 10. Thepin 8, located inhole 11, restrains thehousing 1 from rotating about the axis of thespindle 2 when thespindle 2 is rotated byshaft 6. This simple arrangement is advantageous since it allows the variable resistance device to be displaced to follow any longitudinal displacement (ie. in the direction indicated by arrows A, B) or lateral displacement (ie. in the direction indicated by arrows C, D and E, F) of the end ofshaft 6 which is coupled to thespindle 2, such displacement of the shaft taking place as a result of play in bearings which support it. The arrangement also allows the variable resistance device to tilt to accommodate a situation where theshaft 6 is not perpendicular to thesupport 9, or as a result of theshaft 6 being bent. - In order to avoid backlash resulting from clearance between the
pin 8 and the sides of the hole 11 a suitably resilient material such as a spring or rubber (eg. silicone rubber) can be applied between the pin and sides of the hole to take up the clearance whilst permitting the necessary displacement to occur., - Although the
pin 8 is shown in Figures 1 and 2 as having parallel sides, it may be advantageous for the pin to be formed of a barrel shape, thereby minimising risk of the pin jamming in thehole 11 when thehousing 1 of the device is caused to be tilted. - One or more further lugs or
flanges 13, similar to lug orflange 10 may be provided, having ahole 14 therein. Such lugs orflanges screw 15 with ahead 16 is passed throughhole 14 inlug 13 and screwed into a hole provided insupport 9. Thehead 16 of the screw is arranged to be sufficiently clear of thelug 13 to permit the required degree of displacement of the device, whilst serving to prevent thespindle 2 from becoming decoupled from theshaft 6, eg. in event of the arrangement being utilised in conditions of severe vibration. It would be preferable to provide at least twofurther lugs 13 withscrews 15, for this purpose. - Instead of using a
plain pin 8, a pin with a head may be substituted, the head engaging thehole 11 inlug 10. Preferably the head of the pin is radiused to provide a barrel shape to prevent the head jamming in the hole when thehousing 1 is caused to be tilted. - It may be necessary, for some applications, to preset the variable resistance device to allow a particular phasing between the device and the shaft coupled thereto. This may be achieved by providing a slot in the
support 9 and providing one or more lock nuts on the end of thepin 8. Thus, with the lock nuts slack, thehousing 1 of the device is rotated, thepin 8 being moved in the slot insupport 9 during this rotation. When a desired setting of the device is attained, the pin is locked in place in thesupport 9 by means of the lock nuts. - Alternatively, the housing of the device can be mounted on a sub-plate such that it can be rotated to a required position on the sub-plate and then clamped, a hole or recess being provided in the sub-plate into which
pin 8 locates, operation being otherwise the same as described with reference to Figures 1 and 2. - It will be apparent to those skilled in the art to which this invention relates that a number of alternative embodiments can be envisaged which fall within the scope of the invention.
- For example, instead of the
rigid pin 8 being secured to support 9 and located in thehole 11 in the lug orflange 10, thepin 8 could be secured to lug orflange 10 or directly to the face of the housing of the device and be arranged to be located i'n a hole provided in thesupport 9. Alternatively a disc or plate (not shown) could be clamped to the support and provided with an aperture for location by the pin, thus obviating the need to provide an aperture in the support for this purpose. This arrangement also permits a predetermined orientation of the device with respect to the support to be achieved which is valuable for phasing purposes. - Also, instead of using the
rigid pin 8 shown in Figures 1 and 2, a flat spring blade could be substituted which would be secured at one end to thesupport 9 and at the other end to the side of thehousing 1, lug 10 being unnecessary in such an embodiment. This arrangement would permit lateral displacements of the end ofshaft 6 to be accommodated, but in the case where longitudinal displacements of the shaft are also required to be accommodated, the end of the spring blade could be slideably secured in a slot or groove in the side ofhousing 1 or in thesupport 9. - In an alternative embodiment, instead of using a
pin 8 and lug 10, a band of metal or plastics material could be provided encircling, but spaced from, the housing and secured to support 9, a suitably resilient material, such as silicone rubber, being provided between the ban=d and housing to permit displacement of the device whilst restraining the housing from rotating about the axis of thespindle 2. - It is also envisaged, within the scope of the invention, that a plurality of variable resistance devices could be provided arranged in ganged form on a common spindle axis and each provided with the means restraining the housing from rotation whilst permitting displacement to follow displacement of a shaft coupled to a spindle at one end of the ganged assembly. If each of the ganged devices is provided with a lug or flange, as denoted by
reference numeral 10 in Figures 1 and 2, then asingle pin 8, extended to pass through the holes in the lugs of all the devices, could be used to allow displacement .of the assembly when displacement of the end of the shaft coupled thereto occurs. - A still further embodiment of the invention is illustrated in Figures 3 and 4.
- A rotary variable electrical resistance device, eg. a potentiometer, is constructed comprising a
housing 21 of metal or rigid plastics material containing essential elements as previously described with reference to Figures 1 and 2. Arotatable spindle 22 extends from the housing for adjusting the setting of the device,spindle 22 being intended to be rigidly coupled to the end of a rotatably supported shaft (such as theshaft 6 shown in Figures 1 and 2) whose angular rotation is to be followed by the variable resistance device. - To permit the
device housing 22 from rotation about the axis of thespindle 22 when the spindle is rotated, the following arrangement is employed. a disc shapedmember 23 is arranged to be clamped at its periphery to asupport 24 by means of a stepped ring shapedmember 25, usingscrews 26 for securement of themember 25 to thesupport 24. Apin 27 extends from the disc shapedmember 23 for location in anaperture 28 provided in acircular flange member 29 having a hole through its centre and secured to thehousing 21 of the device, concentrically with thespindle 22, by means ofnut 30. The disc shapedmember 23 andsupport 24 each have a hole therein through which thespindle 22 may pass. Theflange member 29 is shaped for location within the stepped ring shapedmember 25 such that clearance is provided atregion 31 between theflange member 29 and ring shapedmember 25 to permit thedevice spindle 22. Thepin 27, located inaperture 28 in theflange member 29, restrains thehousing 21 from rotation about the axis of thespindle 22 when the latter is rotated. - In a modification of this further embodiment (not shown) instead of
pin 27 being provided on the disc shapedmember 23, it may be provided extending from theflange member 29 and arranged to be located in an aperture provided in the disc shapedmember 23. With this arrangement, the disc shapedmember 23 may be eliminated if desired and the pin located in an aperture provided in thesupport 24. In this latter case the ring shapedmember 25 would be secured to thesupport 24 without the intermediary of the disc shapedmember 23. - A further advantage of the present invention is particularly evident where a variable resistance device is operated in conditions where mechanical vibration exists. Where a device of the prior art is rigidly mounted and coupled to an operating shaft, such vibration sometimes results in what is known in the art as 'dither'. This involved the cyclic movement of the wiper of the device on the resistance track over a range of frequencies and relatively small angular amplitudes and can result in wear occurring on the track. With the present invention, a small amount of slackness or resilience in the coupling between the housing of the device and support advantageously attenuates the effect of such vibrations and reduces the effect of 'dither' wear on the resistance track.
Claims (20)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE8181303475T DE3174395D1 (en) | 1981-07-28 | 1981-07-28 | Variable electrical resistance device |
EP19810303475 EP0070934B1 (en) | 1981-07-28 | 1981-07-28 | Variable electrical resistance device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP19810303475 EP0070934B1 (en) | 1981-07-28 | 1981-07-28 | Variable electrical resistance device |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0070934A1 true EP0070934A1 (en) | 1983-02-09 |
EP0070934B1 EP0070934B1 (en) | 1986-04-16 |
Family
ID=8188360
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19810303475 Expired EP0070934B1 (en) | 1981-07-28 | 1981-07-28 | Variable electrical resistance device |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0070934B1 (en) |
DE (1) | DE3174395D1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0229446A2 (en) * | 1985-09-17 | 1987-07-22 | Crystalate Electronics Limited | Rotary type potentiometer |
EP0575918A2 (en) * | 1992-06-26 | 1993-12-29 | Wilhelm Ruf KG | Mounting means for supporting an electrical device |
US5858896A (en) * | 1996-10-01 | 1999-01-12 | Nippon Sheet Glass Co., Ltd. | Ultraviolet and infrared radiation absorbing glass |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2921285A (en) * | 1959-01-19 | 1960-01-12 | Oilgear Co | Preset transducer assembly |
DE2735673A1 (en) * | 1976-08-06 | 1978-02-09 | Denki Onkyo Co Ltd | POTENTIOMETER |
US4250481A (en) * | 1978-11-21 | 1981-02-10 | Kaufman Lance R | Variable resistance device for thick film circuitry |
GB2067846A (en) * | 1980-01-12 | 1981-07-30 | Colvern Ltd | Variable electrical resistance device |
-
1981
- 1981-07-28 EP EP19810303475 patent/EP0070934B1/en not_active Expired
- 1981-07-28 DE DE8181303475T patent/DE3174395D1/en not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2921285A (en) * | 1959-01-19 | 1960-01-12 | Oilgear Co | Preset transducer assembly |
DE2735673A1 (en) * | 1976-08-06 | 1978-02-09 | Denki Onkyo Co Ltd | POTENTIOMETER |
US4250481A (en) * | 1978-11-21 | 1981-02-10 | Kaufman Lance R | Variable resistance device for thick film circuitry |
GB2067846A (en) * | 1980-01-12 | 1981-07-30 | Colvern Ltd | Variable electrical resistance device |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0229446A2 (en) * | 1985-09-17 | 1987-07-22 | Crystalate Electronics Limited | Rotary type potentiometer |
EP0229446A3 (en) * | 1985-09-17 | 1988-04-27 | Crystalate Electronics Limited | Rotary type potentiometer |
EP0575918A2 (en) * | 1992-06-26 | 1993-12-29 | Wilhelm Ruf KG | Mounting means for supporting an electrical device |
DE4221024A1 (en) * | 1992-06-26 | 1994-01-05 | Ruf Kg Wilhelm | Holding device for mounting an electrical component which can be actuated by a rotatable shaft on an object |
EP0575918A3 (en) * | 1992-06-26 | 1994-08-03 | Ruf Kg Wilhelm | |
US5858896A (en) * | 1996-10-01 | 1999-01-12 | Nippon Sheet Glass Co., Ltd. | Ultraviolet and infrared radiation absorbing glass |
Also Published As
Publication number | Publication date |
---|---|
DE3174395D1 (en) | 1986-05-22 |
EP0070934B1 (en) | 1986-04-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4373269A (en) | Adjustment mechanism | |
US6921994B2 (en) | Motor having rotatable shaft coupled with worm shaft | |
US4520987A (en) | Structure of supporting a stepping motor | |
JPS58103846A (en) | Motor vibration preventive mounting device | |
EP0070934B1 (en) | Variable electrical resistance device | |
US4400686A (en) | Variable electrical resistance device | |
US20070065225A1 (en) | Coupling and shaft assembly | |
US10760667B2 (en) | Transmission housing unit having an axial disk | |
GB2058943A (en) | Cooling fan assemblies | |
GB2067846A (en) | Variable electrical resistance device | |
US4367373A (en) | Two-axis electromechanical controller | |
US5590149A (en) | Mirror mount | |
EP0431803A2 (en) | Lamp assembly | |
US6314829B1 (en) | Steering assemblies | |
SE508909C2 (en) | System for centering a rotating element | |
US2590287A (en) | Shaft coupling | |
JPS629097A (en) | Variable adjusting mechanism | |
EP0194803B1 (en) | Magnetic head adjusting device | |
US3054076A (en) | Potentiometer | |
US5046379A (en) | Remote control apparatus | |
US3112465A (en) | Ganged potentiometer structure | |
JP3111675B2 (en) | Surveying device drive | |
SU1737390A1 (en) | Coordinate mechanism | |
US4039262A (en) | Clamp holds members in rotatably adjusted position | |
SU607706A2 (en) | Automatic adjustment device for up-tuning of feed and tolerance control system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Designated state(s): BE DE FR IT NL SE |
|
17P | Request for examination filed |
Effective date: 19830805 |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: CRYSTALATE ELECTRONICS LIMITED |
|
ITF | It: translation for a ep patent filed |
Owner name: BARZANO' E ZANARDO ROMA S.P.A. |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): BE DE FR IT NL SE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19860416 Ref country code: FR Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY Effective date: 19860416 Ref country code: BE Effective date: 19860416 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Effective date: 19860430 |
|
REF | Corresponds to: |
Ref document number: 3174395 Country of ref document: DE Date of ref document: 19860522 |
|
EN | Fr: translation not filed | ||
NLV1 | Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19870401 |