Abstract: A temperature-adjusted heater for transfusion includes a clamping member and a temperature-controlled unit. The clamping member defines a through hole, for a transfusion tube pass through and fixed therein. The temperature-controlled unit connecting to power supply, includes a heating member, an adjusting current circuit, and an adjusting button. The heating member is mounted in the clamping member, in communication with the through hole, and firmly against the transfusion tube. The heating member and the adjusting button are in series with the adjusting current circuit, and the adjusting button is operated to change the resistance value of the adjusting current circuit.

Abstract: The invention relates to a control and regulating device for a drive arrangement of a displaceable press beam of a bending press in particular a press brake, comprising a protective housing having an access orifice for a foot of an operator, and comprising a pedal-type actuating element disposed in the protective housing At least one detection means connected so as to communicate with a control and monitoring system of the bending press is assigned to the actuating element and is provided in the form of a motion profile detection means.

Abstract: A light emitting key is disclosed. A through hole is made through piezoresistive layer; a light source is arranged under the bottom of the light emitting key. When the light source is turned on, light beams shall emit out of the top substrate. The light emitting effect of the key facilitates it to be used in a dark area such as an aircraft flying in the night sky.

Abstract: A variable speed toggle switch that allows a user to reverse a rotational direction of a motor and supply variable amounts of power to a motor, such as in a power tool, for example, a power drill. A trigger can include a gear segment that meshingly engages a gear on a potentiometer to electrically communicate the actuation direction and actuation amount of the trigger to a microprocessor. The microprocessor can then signal to an H-bridge, or to a series of transistors, the actuation direction and actuation amount of the trigger. A motor or other device can be powered by a power source in an amount corresponding to the actuation amount, and in a direction corresponding to the actuation direction of the trigger.

Abstract: A variable speed toggle switch that allows a user to reverse a rotational direction of a motor and supply variable amounts of power to a motor, such as in a power tool, for example, a power drill. A trigger can include a gear segment that meshingly engages a gear on a potentiometer to electrically communicate the actuation direction and actuation amount of the trigger to a microprocessor. The microprocessor can then signal to an H-bridge, or to a series of transistors, the actuation direction and actuation amount of the trigger. A motor or other device can be powered by a power source in an amount corresponding to the actuation amount, and in a direction corresponding to the actuation direction of the trigger.

Abstract: A variable speed toggle switch that allows a user to reverse a rotational direction of a motor and supply variable amounts of power to a motor, such as in a power tool, for example, a power drill. A trigger can include a gear segment that meshingly engages a gear on a potentiometer to electrically communicate the actuation direction and actuation amount of the trigger to a microprocessor. The microprocessor can then signal to an H-bridge, or to a series of transistors, the actuation direction and actuation amount of the trigger. A motor or other device can be powered by a power source in an amount corresponding to the actuation amount, and in a direction corresponding to the actuation direction of the trigger.

Abstract: A variable speed toggle switch that allows a user to reverse a rotational direction of a motor and supply variable amounts of power to a motor, such as in a power tool, for example, a power drill. A trigger can include a gear segment that meshingly engages a gear on a potentiometer to electrically communicate the actuation direction and actuation amount of the trigger to a microprocessor. The microprocessor can then signal to an H-bridge, or to a series of transistors, the actuation direction and actuation amount of the trigger. A motor or other device can be powered by a power source in an amount corresponding to the actuation amount, and in a direction corresponding to the actuation direction of the trigger.

Abstract: A switch element (1) for actuating a setting parameter on an electronic microdevice, such as a hearing aid, is characterized by a rotary element (7) having peripherally at least three contact points (9), said contact points being connected to one another in electrically conductive fashion. Furthermore, the switch element has an elastically mounted reset element connected with the rotary element as well as at least two electric leader contacts (3, 5), which can be switched into electrically conducting contact by turning the rotary element via the contact points.

Abstract: An overvoltage protection device includes a slide-in protective member and at least one non-linear resistance element in the slide-in protective member. A cable is connected to the at least one non-linear resistance element by solder, and a sliding member is biased against the cable. The sliding member is capable of reciprocal movement in the slide-in protective member. A visual indicator lever is engaged with the sliding member so that movement of the sliding member moves the visual indicator. A positioning element is engaged with the sliding member so that movement of the sliding member moves the positioning element.

Abstract: A switch for controlling a rotational speed of a motor includes an operation member, a first circuit, and a second circuit. The first circuit includes a brush coupled to the operation member having a contact and also includes a variable resistive plate having a resistance that changes in response to a contact position of the contact point of the brush, so that the first circuit outputs a control signal to the motor according to the contact position of the contact point. The second circuit connects the brush and the resistive plate without through the contact point when the brush is positioned at a given position relative to the resistive plate.

Abstract: A two-phase rotary encoder is provided which includes a substrate for the encoder which is double-faced and has a copper-foil-bonded substrate etched thereon, a first ring-shaped electrode pattern and a second ring-shaped electrode pattern formed concentrically around a center hole on the substrate, a smooth, level ring-shaped comb electrode pattern formed on an outermost periphery of the substrate, wiring patterns which cover the electrode patterns through each of external connecting terminals provided on the substrate, and a common external connecting terminal provided on an edge of the substrate, formed on a surface thereof via the center hole or a through hole. The rotary encoder further includes a resin-molded case, a shaft, a gear-shaped rotor, a click mechanism and a tact switch mechanism.

Abstract: The present invention relates to switch or volume control assemblies, in particular to switch or volume control assemblies to be mounted in e.g. hearing aids, said assembly comprising a movable member, such as a wheel-like member positioned between at least two detachable parts defining the exterior of a housing, the movable member having a part extending out of the housing, the movable member engaging a contact member so as to move the contact member with the movable member.

Abstract: A knob having a button for a rheostat includes a base, at least one arcuate contacts, a hub, a pushbutton cap with a conductive arc corresponding to the arcuate contacts and a biasing member mounted in the pushbutton cap. The biasing member can be mounted between the pushbutton cap and the hub or the base to make the pushbutton cap return to its original position when pressure on the pushbutton cap is released. A rotating shaft of a rheostat extends out from the base and connects to the hub. The pushbutton cap is mounted on the hub to turn the hub and the rotating shaft to change resistance of the rheostat.

Abstract: A switch mechanism for an electrical slide switch that has a detenting or clicking action is disclosed. The switch mechanism provides such detenting action in a mechanism that has a switch lever that moves through an arcuate path of movement and provides a uniform resistance to movement through the entire range of movement of the switch lever.

Abstract: An accelerator module for an electric vehicle has a pivotal actuator upon which is mounted a wiping element for wiping engagement with variable and constant resistance elements formed upon a printed circuit board mounted within a housing. A normally-open switch mechanism is also mounted upon the printed circuit board, and in order to delay the closure of the normally-open switch mechanism from its OPEN state to its CLOSED state, the actuator is provided with a spring-biased overtravel plunger mechanism which engages a push-button element of the switch mechanism so as to retain the switch in its OPEN state until the actuator has been moved a predetermined distance corresponding to a predetermined amount of depression of the accelerator pedal of the electric vehicle.

Abstract: A variable resistance control device and switch has a base, made of insulating material, a rheostat, mounted to the base, and a switch, mounted to the base. The rheostat includes a variable resistor trace, positioned on the base, a collector trace, positioned on the base next to and insulated from the variable resistor trace. The rheostat includes an actuator, slidably coupled to the base, for sliding over a length of both the variable resistor trace and the collector trace to make electrical contact therebetween. The rheostat also includes a first set of contacts, that are 1) electrically coupled during operation of the rheostat, and are 2) electrically isolated during operation of the switch; and a second set of contacts, that are 1) electrically isolated during operation of the rheostat, and are 2) electrically coupled during the operation of the switch.

Abstract: A rotary variable resistor with switch having a switch mechanism, in particular, a rotary variable resistor with switch corresponding to an ultrathin rotary variable resistor. Such a rotary variable resistor having a switch mechanism has dimensions, especially thickness, which are only slightly larger than that of a conventional ultrathin rotary variable resistor. Moreover, such a rotary variable resistor is easy to assembly due to the small number of parts, is reliable, and generates a fairly loud and easily recognizable clicking sound each time the switch is turned on or off, which can be both easily felt and heard by the user.

Abstract: A method and apparatus for actuating an electrical switch and providing a variable electrical resistance usable to sense displacement of a movable member. The apparatus includes a housing for receiving the electrical switch, a variable resistance element, and an actuator with a body member and a transverse cylindrical sleeve. An electrically conductive wiper is coupled to the actuator and contacts the variable resistance element, which varies with pivotal movement of the actuator. The body member is pivotably supported by an aperture of the housing about an axis of the cylindrical sleeve, and a spring member biases the actuator toward an initial position, wherein the actuator is pivotable against the bias of the spring to actuate the electrical switch and to provide the variable resistance by positioning the electrically conductive wiper along the variable resistance element.

Abstract: A pull chain switch circuit device for a stepless control of brightness of lighting fixtures of a ceiling fan is composed of a central control unit, a voltage stabilizing and rectifying unit, a pull chain switch, a protective unit, a zero crossing loop, and a gate unit. The input end of the voltage stabilizing and rectifying unit is connected with an alternating current source, whereas the output end of the voltage stabilizing and rectifying unit is connected with the central control unit. The pull chain switch has one end connected with the output end of the voltage stabilizing and rectifying unit. The protective unit is connected with the alternating current source and the central control unit. The zero crossing loop is connected with the alternating current source and the central control unit for detecting a time point at which the alternating current source becomes 0V.

Abstract: An improved multiturn potentiometer consists of a rotor assembly including a wiper in electrical contact with an output terminal and an annular resistance strip. The annular resistance strip is electrically connected to a source of potential through one or more potentiometric rotary switches which are activated periodically change the magnitude of potential to the annular resistance strip. Movement of the wiper along the annular resistance strip varies the potential to the output terminal. Activation of the rotary switches is effected by rotation of the rotor assembly and increases or decreases the potential to the annular resistance strip depending on the direction of rotation. Each potentiometric rotary switch is capable of multiple variations of potential so that each revolution of the rotor assembly effects movement of the rotary switch to supply a new potential to the annular resistance strip.

Abstract: An accelerator module comprises a printed circuit board having resistance elements mounted thereon, and an actuator pivotably mounted upon the printed circuit board and having a wiper member mounted upon a first end of the actuator. A rotary input shaft, connected to an accelerator pedal of an electric vehicle, has an input shaft arm fixedly mounted thereon, and the input shaft arm is pivotably connected to a second end of the actuator whereby the structural arrangement defines a mechanically advantaged linkage system whereby a predetermined pivotable movement of the rotary input shaft and its associated input shaft arm translates into an enhanced, enlarged, or magnified pivotable movement of the actuator and its associated wiper member for movement along the resistance elements of the printed circuit board.

Abstract: A notebook computer or other electronic device has a flexible cable interconnecting electronic circuitry in a base with electronic circuitry in a cover. A flexible potentiometer is coupled to said flexible cable in a location which bends when said cover is opened and closed with respect to the base. The resistance of the flexible potentiometer has a first value when the cover is closed and has a second value when the cover is open. A detection circuit is responsive to the resistance of the flexible potentiometer and generates an output signal which indicates whether the cover is open or closed.

Abstract: A rotary dimmer switch assembly for use with a vehicle push-pull switch controls at least one light dimming function. The rotary switch assembly comprises a stationary cam contact assembly, and a rotating carder assembly which carries a circuit element having an exposed circuit trace surface. The cam contact assembly is fixed to a circuit board and has a plurality of contact arms having one end biased against the circuit element circuit trace surfaces and the other end electrically connected to the circuit board. The cam contact assembly guides the rotation of the carrier assembly about the longitudinal axis of the push-pull switch. The circuit element rotates with the carrier assembly, which is rotated by rotation of a push-pull switching component, and the circuit trace surfaces sweep across the contact arms thereby controlling the light dimming function. A method of assembling the rotary potentiometer assembly is also disclosed.

Abstract: An electric tool rheostatic device in a switching arrangement is provided for regulating the speed of an electric motor in an electric tool. A circuit board for receiving electronic components is disposed in a switch housing. A potentiometer disposed within the switch housing includes a potentiometer slider operatively connected with a manually-operated actuating member and a resistance track that is constituted by a chip resistance element produced independently of the circuit board according to surface mounted device technology and mounted on the circuit board independently of the potentiometer slider. Upon assembly of the switching arrangement the potentiometer slide is adjustably located on the resistance track by the manually-operated actuating member for controlling resistance.

Abstract: A rotary, push-pull switch (20) for use in an automobile has a rotating ceramic coated metal substrate rheostat (48) and a supplemental switch (52) which opens and closes a dome light bypass circuit. The supplemental switch (52) is mounted internally to the rotary, push-pull switch (20) adjacent to the rotating rheostat (48) disposed on a shaft (36). A projection (88), which is radially disposed on the shaft (36), is used to actuate the supplemental switch (52) by engaging a resilient contact leaf (60) when the shaft (36) is rotated sufficiently. The engagement of the projection (88) and contact arm (60) causes the separation of a contact (62) and terminal (64), opens the dome light bypass circuit, and precludes energizing the dome light.

Abstract: A rotary switch for controlling electrical circuitry in ranges, ovens, etc., to be manually adjusted for control of function cycles. Included with the manually operated function selector are means for determining the position of the function selector providing at the same time via a low voltage DC communication link, with a solid state microprocessor or similar unit as used for control of ranges, ovens, etc.

Abstract: A circuit and apparatus for sensing the adjustment of a variable impedance device includes an elongated switching element having an alternating series of conductive and non-conductive areas. The conductive areas are electrically connected. As the device is adjusted, a wiper alternately operates the switch between open and closed states. A circuit detects the switch-state change and provides a signal which indicates that the device is being adjusted. The signal can, in turn, determine the output of a dimming circuit, a wireless transmitter, etc., or can determine whether power is provided to a microprocessor or the like. In another embodiment of the invention, a variable impedance device includes an end-of-travel return mechanism.

Abstract: A lever switch for a vehicle windshield wiper having a base for attaching to a steering column, a rotational shaft rotatably connected to the base, a first switch knob connected to the rotational shaft, and a second switch knob rotatable mounted around a portion of the rotational shaft. The lever switch includes mounting the switch mechanisms for the first and second switch knobs around a portion of the rotational shaft, thereby allowing the rotational shaft to be shortened and the lever switch to be connected at an angle to the base.

Abstract: A dual function rotary assembly (100) functions as a potentiometer and a momentary switch. The dual function assembly (100) includes a rotary shaft (106) that when rotated to a predetermined position, such as its final rotational position, may be pulled to provide a momentary contact between two switching terminals (116, 126).

Abstract: A variable resistance switch includes first and second flexible contact arms engageable by a pair of cam followers operable sequentially by an actuator movable in a first and an opposite direction. The actuator also carries a wiper movable therewith over a variable resistance coupled to a terminal. The first contact arm is operable upon initial movement of the actuator in a first direction to complete a first circuit through the switch, and the second switch arm is operable upon further movement of the actuator in the first direction to complete a second circuit through the switch and to place the variable resistance in circuit between one of the switch arms and the terminal. Further movement of the actuator in the first direction is operable to move a wiper over the resistance to vary the resistance in circuit with the terminal. A pivotal trigger is coupled to the actuator for moving the same in the first direction, and a spring biases the cam in the opposite direction.

Abstract: A variable resistor having a switching function includes a base plate, a first electrode formed on the base plate, a second electrode formed on the base plate, a third electrode formed on the base plate, and a fourth electrode formed on the base plate simultaneously with the formation of the second electrode. A resistive element connects electrically the first and the second electrodes, a first switching element is provided and includes two brushes which slide on the surfaces of the third electrode and the resistive element, respectively. A second switching element is movable together with the first switching element and includes two brushes which slide on the surfaces of the first electrode and the fourth electrode, respectively.

Abstract: A variable resistor with a switch which minimizes appearances of an arc and prevents incomplete contact between contacts of the switch originating from such an arc. The variable resistor with a switch includes a torsion coil spring having one end connected to a movable contact element supported for pivotal motion around a support shaft and the other end connected to a cam member also supported for pivotal motion around the support shaft. When the cam member is pivoted by movement of a slider receiver, a connecting point between the torsion coil spring and the cam member moves across a straight line interconnecting the support shaft and another connecting point between the torsion coil spring and the movable contact element so that a movable contact on the movable contact element is instantaneously brought into or out of contact with a fixed contact to turn the switch on or off irrespective of the speed of movement of the slider receiver.

Abstract: A composite headlight switch with buzzer circuit for use in a vehicle with, for example, a dome light, the dome light switch being located in line with the remaining switch elements in a front area of the overall switch structure, which front area was previously occupied by a spacer, rather than having the dome light switch located outboard on the exterior side of the overall switch structure as in the prior art. The dome light switch structure comprises front and back elements which include sandwiched between them a centrally located driver having a laterally extending peripheral cam.

Abstract: A control switch and potentiometer assembly for use in an in-the-canal type hearing air comprising a miniature single pole, single or double throw, push-pull control switch and rotary potentiometer. The components of the control switch and potentiometer are mounted within a durable thermoplastic resin housing which is anchored within the hearing aid. A single control knob for actuation of the control switch and potentiometer is raised and shaped to permit gripping between the fingertips of the user for removing the hearing aid from the ear canal.The switch contacts and switch wiper are designed such that the process of pulling on the potentiometer control knob to remove the hearing aid will extend the control switch, thereby disengaging a normally closed switch contact and opening a battery powered circuit so as to turn the hearing aid off.

Abstract: A locking slide switch is adapted to set a resistor depending on the length f travel. A key body has a row of teeth with which a pinion meshes. A locking push-button is provided on the shaft of the pinion. In order to make locking from both sides possible, a second pinion or an elongated pinion is guided in the row of teeth. On this pinion is provided a second push-button, which can also be blocked. An on-off switch is additionally provided.

Abstract: A sliding electrical control provides a method for controlling the power to electrical systems, such as lamps, motors, etc. from more than one location. The control is designed to be mounted on one side of a plate and operated from the other side. It thus permits a slide for operating the control to be mounted closer to a wall than was possible before. In a preferred embodiment, the control includes a biasing spring, which reduces any tendency to rock, rather than slide, when the motion of the slide is begun.

Abstract: An electrical device that includes a variable resistor and a switch mechanism. The variable resistor has a control element disposed to be moved linearly to change the electrical resistance of the device according to the position of the control element. A switch is positioned adjacent the variable resistor and the switch includes a movable contact holder having a first electrical contact mounted thereon. A second electrical contact is positioned in the switch such that movement of the contact holder selectively brings the first electrical contact into contact with the second electrical contact. An actuator moves the movable contact holder when the control element is at one extremity of a linear movement.

Abstract: A click mechanism of slide volume control ensures judgement of a center stop position of a lever by a difference in the click touches and allows many stop positions of the lever by providing holes on both sides of the lever inserting hole of the upper surface plate of the frame and providing convex portions on the ends of elastic arms of a plate spring which engage the holes.

Abstract: In electrical control apparatus having a first member disposed in an opening in a second member, the first and second members being adapted and arranged for relative movement with respect to each other, a safety device for covering the open portions of the opening as the first member moves relative to the opening. A primary shield is located adjacent to and overlaps the opening. The primary shield is operatively associated with the first member for movement in response to relative movement of the first member. The primary shield has a shape adapted to permit unrestrained movement of the first member while overlapping the open portions of the opening to cover those portions for all positions of the first member in the opening.

Abstract: A device forming a potentiometer for varying the resistance of an electrical circuit, and a switch for changing the state of current conduction in the circuit. The switch has a casing fastened to the potentiometer, and the potentiometer has a casing and a plate joined together. The device has a rotatable component having a central protuberance extending through the plate. A first discoidal element is carried by the rotatable component and has a metallic cursor. A resistance track and a metallic collector are stationarily mounted on the plate. The cursor is continuously and simultaneously in contact with the resistance track and the collector. A second discoidal element is mounted in the switch casing for engagement by the protuberance and is releasably coupled to the rotatable component when the switch is coupled to the potentiometer. A fixed contact is mounted on the switch casing and a movable contactor arm is movable mounted on the switch casing.

Abstract: A rotary potentiometer is provided with a switch, preferably as a final control element for the control of electrical machinery. An enclosed, prefabricated rotary potentiometer component with its own casing is inserted in a cup-shaped upper casing that is open on one side. Switching contact supports are housed in the upper casing by means of peripheral wall sections. These contact supports are actuated by a cam actuating member that is mounted on a fulcrum pin so as to permit play and simultaneously also effect rotation and retention of the potentiometer component in the upper casing.

Abstract: In a switch, for example, for a device such as a drill, a key switches an ectrical switching bridge at the beginning of the key displacement. A variable resistor is adjusted depending on the travel of the key, thereby controlling device speed. In order to achieve an adjustment of the key end stop, a slide displaceable in the transverse direction is mounted on the key, which slide has a stop edge projecting in the longitudinal direction. A stop border is provided on the switch cover and configured relative to the travel of the slide so that the distance between the stop edge and the stop border varies according to the displaced position of the slide, thereby enabling operator control of the device speed.

Abstract: A dimmer switch which includes a rotary potentiometer mounted on a board secured to, and projecting normal from, a switch arm support bracket. The support bracket is secured to a face plate. A cover housing cooperates with the face plate to enclose the bracket and board and any circuit components, including the potentiometer, which are mounted on the board. A switch arm assembly carries trunnion studs pivotally supported in receiving trunnion sleeves forming part of the support bracket, and the switch arm assembly further includes a pivot lever projecting through an aperture in the face plate, and a toggle end to which is adjustably secured an arcuate gear segment. A projecting operating shaft of the rotary potentiometer carries a gear drivingly engaged by the gear segment on the switch arm.

Abstract: A potentiometer which provides the function of an on/off switch includes a center conductor connected to a conductive ring and a resistive element concentrically disposed about the conductive ring. The resistive element includes a pair of termination pads and one of the pads includes a branch which is situated outside the outer periphery of the resistive element. As a wiper arm traverses the resistive element it remains in contact with the branch for a brief distance and then loses contact with it. This causes the value of the resistance in the potentiometer to make an abrupt shift in magnitude which can be used to initiate various switching functions.

Abstract: In a push-button switch, the switch element is a cantilever (2) of thin silicon strain gauge material with a small magnet (1), e.g. of samarium cobalt alloy at its free end. Adjacent to the free end there is an annular magnet (3), e.g. of plastics material impregnated with samarium cobalt alloy, on the push rod (4) of the switch. The annular magnet (3) is so poled that movement of the rod (4) causes, due to magnetic forces, the deflection of the silicon strain gauge to give an electrical output.The return force, plus collapse action, is provided by a soft iron collar (5) on the switch structure.

Abstract: A control unit, adapted to control a reversible, variable-speed electrical motor includes a control lever protruding through a U-shaped slot in a housing. Movement of the lever from one side to the other of the U-shaped slot controls the direction of rotation of the motor, and its position along a side of a slot determines the speed of rotation. The control lever is mounted to a pivotally mounted support member, which carries a linear potentiometer operated by the control lever, and includes a protruding portion which carries a toggle switch. The handle of the toggle switch is substantially restrained from motion, so that the switch is actuated to reverse the motor when the control lever is moved from one side of the U-shaped slot to the other.

Abstract: An electrical switch comprises, in addition to its switching mechanism or mechanisms, a potentiometer including a potentiometer plate and a slider which is advantageously moved/simultaneously with the actuation of the switching mechanisms. The switch requires terminal elements not only for the switching mechanism or mechanisms but also for this potentiometer. Consequently, an electrical connection must be provided within the switch between the inner ends of the terminal elements and the potentiometer plate. In accordance with the invention, the potentiometer plate is connected to the terminal elements by slip-in attachment which not only ensures a safe hold but also effects the electrical contact. To this end, the potentiometer plate is inserted into slot-shaped seats of the terminal elements, which are prevented from being unduly enlarged by suitable means.

Abstract: A switch for controlling the current to a load combining an ON-OFF switch in series with a variable resistor. Switch has a housing which includes an actuator guided along a dimension of the housing. An opening through the actuator permits a portion of the regulator switch to pass through the actuator for operation. The actuator also includes a cam surface for operating the ON-OFF switch.

Abstract: A rotatable control with an integral switch comprises conductive inner and outer shaft in a concentric configuration. The inner and outer shaft are electrically insulated from one another and frictionally coupled to allow concentric simultaneous rotation. The assembly is covered with a flexible insulating shroud which has a switch contact located on the upper interior surface thereof. Conductive spring members are clipped around the lower portion of the inner and outer shaft to allow electrical connection to a circuit board.

Abstract: A switching and control apparatus, comprising: a stepping switch with a rotatable controller barrel; a regulator having a rotatable setting shaft drivable by the controller barrel; a clutch, including a regulator-side coupling member fixed for rotation together with the setting shaft, effective over a predetermined range of angular regulator settings, in which the controller barrel drives the setting shaft, and ineffective at angular settings beyond the predetermined range, during which the setting shaft is not driven by the controller barrel; and, a spring-loaded arrangement for restraining rotational movement of the regulator-side coupling member during movement of the controller barrel beyond the predetermined angular range.