Abstract: A multi-way change-over switch which is compact with a reduced number of parts and is improved in operability. The multi-way change-over switch comprises a manually operable lever, a rotary slider supporting the manually operable lever for rocking motion thereon and connected for integral rotation by rotation of the manually operable lever, a rotary switch mechanism having a plurality of contacts which are changed over by rotation of the rotary slider, a slide switch mechanism connected to be slidably moved in a linear direction to change over a plurality of contacts thereof by rocking motion of the manually operable lever, and a controlling mechanism for controlling a direction of sliding movement of a slider of the slide switch mechanism. The manually operable lever can be tilted and rotated to operate the slide switch mechanism and the rotary switch mechanism, respectively, to achieve various switching operations.

Abstract: A joystick device to be used in video games or the like having an improved construction to prolong the life of the switches used in the joystick device. The improved construction includes a conical spring located between a diaphragm and an actuator which reduces the force ultimately applied to the switches by the user of the video game. The actuator and the diaphragm surround portions of the shaft, and the actuator has a tapered inner wall which allows pivotal movement of the shaft which further reduces the force ultimately applied to the switches.

Abstract: An integrally formed joystick for a computer keyboard having a central hollow housing loosely fitted over a center key and capping the same, the stick having two or more spaced arms extending externally from the central housing and adapted to make contact by depression of an arm or arms with a key or keys adjacent to the center keys to effect a desired graphic display in a direction selected by the operator.

Abstract: In a switch device in which four switches are operated by depression of four depressing surfaces which are defined by diagonal lines on a rectangular operating knob, the four switches comprise: four principal contact assemblies which are each arranged in such a manner as to be aligned with one of the depressing surfaces to form part of the switches, and each respective principal contact assembly is turned on when the corresponding depressing surface is depressed; and two common contact assemblies which are arranged at substantially opposite ends of one of the diagonal lines of the operating knob in such a manner that each of the two common contact assemblies is aligned with two adjacent ones of the depressing surfaces to form part of two adjacent switches, and each common contact assembly is turned on by depression of any one of the two adjacent depressing surfaces, which results in a switch device that is simple in construction and low in manufacturing cost.

Abstract: A multi-directional switch assembly, such as a joypad or joystick for an electronic game apparatus, including a printed circuit board, a resiliently deformable member having contact elements thereon and an input member mounted to deform the deformable member to effect closing of the switches. The input member is pivotally mounted by a post assembly, and the post assembly is supported by the game apparatus housing in a manner which is independent of the printed circuit board to substantially isolate the printed circuit board from thrust forces manually applied to the joypad input member.

Abstract: An operation control device for a construction machine is constructed of a remote control valve having a member moveable in proportion to an operating lever stroke and having a plurality of devices engaged with the member and operable in association therewith. A part of the plural devices include a proportional hydraulic signal generator for reducing a hydraulic pressure from a hydraulic pressure source in proportion to a moving quantity of the member and generating a signal as a pilot pressure, and a part or the other of the plural devices including a proportional electric signal generator for generating an electric signal proportional to the moving quantity of the member.

Abstract: A movable handcontroller that permits control while requiring low force-displacement gradient. The handcontroller may be used in a side-arm configuration in that it allows the operator's arm to remain essentially motionless in an armrest while control inputs are made about the fulcrum of the wrist.

Abstract: A multiple electrical switch comprising a casing, a control knob supported on the top edge of the casing for tiltable movement in four directions, a retainer horizontally mounted within the casing and a conversion knob tiltably supported by the retainer and having an upper portion projecting through the central aperture of the control knob. Upper and lower base plates are disposed on respective opposite sides of the retainer, with each of the upper and lower base plates defining a printed circuit board and having a plurality of fixed connecting contacts. The switch further comprise an insulating elastic sheet having a central portion for covering the upper portion of the conversion knob and opposite side peripheral portions for covering respective top surfaces of the upper base plate and each portion including a swell including a movable connecting contact corresponding to a respective one of the plurality of fixed connecting contacts of the upper base plate.

Abstract: A joystick assembly for converting push-button keys to joystick actuation comprises a handle and a multi-arm member, the multi-arm member includes arms located for contact with keys of a computer keyboard, each arm having a depending end for engaging a respective key. The handle inserts perpendicularly through the multi-arm member through a central aperture and is adjustable perpendicularly with respect to the keyboard. Apparatus is incorporated for fastening an end of the handle to a central key of a keyboard.

Abstract: The present invention relates to a switching device for use as a control switch for the posture-adjustable automotive mirror. The switching device according to the present invention comprises plural fixed contacts disposed in a substantially straight line on a substrate housed in an enclosure, moving contacts formed by two electrically conductive balls disposed movably on the substrate, slider element having two slopes which are in contact with the two balls, a box-shaped actuator comprising a slider which houses the slider element, through holes for guiding the slider parallel to the substrate, and a resilient member disposed between the slider element and the slider, which forces the slider element toward the substrate. Thus, the switching device according to the present invention performs well in operation and durability, as well as ensures a contact between the fixed contacts and the moving contacts.

Abstract: A joystick controller apparatus comprises a lever mounted for pivotal motion in at least two directions, a guide defining a preselected shift pattern for the lever, and an indicating arrangement for producing a digital logic representation of the position of the lever relative to the shift pattern. The indicating arrangement comprises energy actuated members positioned at predetermined locations relative to the shift pattern, energy producing members positioned in registry with the energy actuated members for normally actuating the same and shield members interposed between the energy producing members and energy actuated members and movable in response to movement of the lever into positions for respectively permitting and preventing actuation of the energy actuated members by the energy producing members in a predetermined fashion such that said energy actuated members collectively form a representation of the location of the lever relative to the shift pattern.

Abstract: This invention relates to a multiobjective switch opening and closing apparatus which is suitable for use, for example, with a television game machine, comprising a support plate, a guide plate with a guide hole mounted parallel to the support plate, an operating lever mounted pivotably and rotatably on the support plate and reaching the guide hole, a plurality of first switches positioned between the support plate and the guide plate and installed around the operating lever, and a plurality of second switches positioned between the first switches and the support plate and installed around the operating lever. The opening and closing of the first switches are selectively carried out by the pivotal operation of the operating lever whereas the opening and closing of the second switches are selectively carried out by the rotational operation thereof, whereby the opening and closing of a number of switches can be carried out by operating a single operating lever.

Abstract: A leaf spring switch device is composed of an L-shaped base member having a long portion and a short portion. A pair of leaf spring contactors extend through the short portion of the base member and have contacts at one end and terminals at opposite ends. An actuator is mounted on one contactor to move it with respect to the other. The contactors extend along the long portion. The lengths of the long and short portions of the base member are selected to be the same as long and short dimensions of a conventional microswitch with the width of the long portion being one half the length of the short portion. In this way, the leaf spring switch device of the present invention is interchangeable with a conventional microswitch.

Abstract: A multi-directional switch which is utilized for completing selected ones of a number of different electrical circuits is placed in a housing in which the different electrical circuits to be controlled terminate in pairs of spaced-apart conductors located in the bottom of the housing. A cylindrical pushbutton actuating member extends upwardly through a circular opening in the top of the housing. This actuating member has a flange on the lower end which extends radially outwardly from the main body of the actuating member, and this flange is supported on a deformable support which has a circular opening in the center. A ball bearing is placed in the opening the deformable support and engages the bottom of the housing and the bottom of the actuating member.

Abstract: A joystick control unit. The control unit includes a controller, such as a handle, transmitting coil, plurality of receiving coils, and plurality of substrates. The handle may be subjected to spring forces which bias the controller toward a neutral position. The transmitting coil is made of electrically conducting paths on one substrate, and the receiving coils are made of electrically conducting paths on another substrate. One of the substrates is connected to the controller and, together with the controller, is movable in relation to the other substrate, which is located in a substantially fixed position. The controller and interconnected substrate may be moved in a variety of positions such that the controller and attached substrate have at least two degrees of freedom.

Abstract: A control device for electrical wheelchairs or the like having a manual control lever which is so supported that it can be moved in any direction desired, and is biased into a central neutral position by means of a spring. Two electro-mechanical adjustment elements, e.g., resistors or potentiometers, are provided, the electrical starting values of which are dependent on their mechanical settings. Two mechanical transmission devices each transfer only one of two movements of the control lever in directions essentially perpendicular to one another to the mechanical-electrical adjustment elements. The mechanical transmission devices comprise two plastic plates slidably-disposed one over the other, each containing an inclined elongated slot disposed at right angles to each other. The plates carry projecting studs which actuate said electro-mechanical adjustment elements when the plates move.

Abstract: A pulse generator having a plunger for actuating several contacts. The plunger is guided in a housing and is slidable in the direction of and rotatable about its longitudinal axis against the action of a spring and is provided with at least one actuating member capable of entering into non-positive engagement with at least one contact both in at least one of its longitudinally adjusted positions and in at least one of its rotated positions. The plunger has a hole which runs parallel to the direction of sliding and contains a second plunger which is slidable and/or rotatable against the action of a spring associated therewith. There is an actuating member on the second plunger.

Abstract: A Hall-effect control apparatus incorporating an actuator member having a magnetic core, and which is pivotally mounted on a base for movement in X-axis and Y-axis directions. An electrically energized coil excited with a. c. voltage produces a fluctuating magnetic field in the vicinity of the core. Four Hall-effect sensors are mounted on the base, and are arranged to sense changes in the a. c. field as the core member moves. The output of the Hall-effect sensors is both d. c. and a. c.; an electrical circuit connected therewith processes these voltages so as to cancel out any d. c. components thereof. The output of the electrical circuit in turn provides two voltages which are indicative of the X-axis and the Y-axis positions of the actuator member. The device is immune to interruption arising from d. c. fields, such as that of the earth; also significant immunity against error due to temperature fluctuations is realizeable, as is immunity to error arising from aging of the various components.

Abstract: A cursor control accessory is shown as an integral base overlying an array of keys including independently movable cursor control keys. It is provided with a protruding handle for use as a joystick. Outwardly protruding walls are adapted to be freely located between keys in the array and engage the upper surface of the keyboard housing. Recessed key engaging surfaces are provided above each cursor control key and are adapted to depress the selected cursor control key or keys in response to rocking movement of the base relative to the keyboarding housing. Base areas located above non-functional keys are recessed inwardly or relieved to prevent key operation during cursor usage.

Abstract: An accessory is provided for a computerized aircraft flight simulation program which employs a control stick assembly to simulate the forces on and movement of an aircraft control stick which a pilot would actually experience in flight. The accessory employs a joystick extension of at least fifteen inches in length and four springs which extend in orthogonal directions from the joystick extension over pulleys on upright mounting posts to anchoring locations near a mounting base to which the posts are attached. The springs are maintained in tension and are long enough to produce realistic sensations of resistance which a pilot actually experiences in operating the control stick of an aircraft. The springs are arranged in linearly aligned pairs with the springs in each pair working in opposition to each other. Tension on the springs in one pair can be adjusted to simulate elevator trim control in an aircraft. Tension on a spring in the other pair can be adjusted to simulate rudder trim control in an aircraft.

Abstract: A surfing video game in which a surfing figure on a monitor moves over simulated waves to gain playing rewards is controlled by a foot-actuated surfboard simulator. The simulator has a horizontally mounted elongate surfboard having a suspension system consisting of a fulcrum member adapted to support the board to permit tilting in all directions, and a biasing system mounted annularly to the fulcrum which tends to maintain the board in a horizontal position and to dampen tilting movement of the board. An attitude sensor and switch module is mounted on the controller and consists of a gravity-actuated closure member, such as a pendulum or ball bearing, having a common electrical contact and positioned to engage one or more of a plurality of equally spaced electrical contacts located around the periphery of the closure member.

Abstract: The joystick assembly comprises an ergonomically shaped, hand-holdable housing. The joystick shaft passes through an upper face of the housing and the lower end of the shaft is pivotably received in a ball and socket joint. The shaft is pivotable about the joint such that an intermediate portion of the shaft can engage a selected one, or a selected two, of an array of four microswitches each arranged for completing electrical connection to a VDU display. The shaft is biassed towards the neutral position solely by the four microswitches.

Abstract: A method of operating "left" and "right" electric windows in a vehicle is described. A switch has an actuator manipulable, as by pivoting, from a neutral position to respective ones of a "left front", a "right front", a "left rear" and a "right rear" position, relative to the mounting of the switch in the vehicle. The various actuator positions effect the following responses from the windows:"Left front"="left" window "up""Left rear"="left" window "down""Right front"="right" window "up""Right rear"="right" window "down".The switch actuator may also be movable directly to a "front" position which drives both the "left" and "right" windows "up", or to a "back" position which drives both windows "down". Further, manipulation of the actuator in another plane may be used to switch between "front" and "rear" window control.

Abstract: Arrow keys on the keyboard of a desktop computer, computer terminal or displaywriter which control the movement of a cursor are actuated by a manually operated mechanical device resting over the keyboard. The device entails a central control shaft and a plurality of fingers extending outward radially from the shaft toward each of the arrow keys, and preferably toward adjacent keys as well. The control shaft and fingers are pivotally mounted and arranged such that when the control shaft is pivoted in the direction of desired motion of the cursor, the appropriate finger is engaged by the control shaft and pivots downward to depress the corresponding key.

Abstract: The manipulator delivers signals characteristic of the orientation of an operating lever (2) in space. The lever is deflectable by a transverse thrust, from a reference or neutral position, and is elastically returned to that neutral position. The lever (2) is articulated on a casing to control the position of at least one movable member (3) interacting with at least one pick-up (4) to deliver an electrical signal dependent upon the position of the lever. Two cams (7, 8) resiliently biased toward each other oppose to the angular deflection of the operating lever (2) an elastic reaction which differs according to the orientation of the lever (2) with respect to its neutral position. In an embodiment, these cams are carried respectively by a ball joint of the lever and by a piston slidable in the casing and urged by a spring.

Abstract: An electric switch wherein a fixed contact is engaged by a tiltable and reciprocable second contact under the action of an elastic washer or a coil spring. The second contact can be tilted by a projection, which extends from the housing, in cooperation with a flat abutment in the housing. When the projection is tilted, it causes the second contact to pivot relative to the abutment and to become disengaged from the fixed contact. The projection can be tilted by a bar or a tube which must be displaced by a person or object tending to penetrate into a danger zone, such as the nip of two cylinders in a printing machine or a machine tool. A third contact can be provided to be engaged by the second contact when the latter is disengaged from the fixed contact.

Abstract: A pulse generator with a pin-shaped switching plunger for actuating at least one contact is so designed that many switching positions are possible. It is characterized in that the switching plunger (3), which is guided in a housing, is slidable in the direction of and rotatable about its longitudinal axis (5), and that the switching plunger (3) is provided with at least one actuating member (4) which can enter into nonpositive engagement with at least one contact (2.1 to 2.8 and 1.1 to 1.8) both in any of the longitudinally shifted positions and in any of the rotated positions.

Abstract: An improved joystick switch assembly of the type which provides selectable on/off switches to a computer depending upon the position of the joystick. The switch assembly has a generally hemispherical base. When the joystick is tilted in the direction of one of the switches, such switch is closed by contact with the table or other support surface upon which the assembly rests.

Abstract: An outlet connection device transfers motion from outside to inside an explosion proof enclosure and includes a process for using a self-aligning bearing retained in a wall of the enclosure. The self-aligning bearing has flame paths selected to meet minimum safety requirements and contains a shaft for transferring either rotary, axial or joy-stick motion into the enclosure. In a rotary transfer arrangement an electric rotary switch is connected through a blade engaging the shaft passing through the self-aligning bearing.

Abstract: A multiposition precision joystick type control device having a transducer mode in which an actuator button is movable in any lateral direction away from a neutral position to cause flexure of flexible bar mechanism along one or both of two orthogonally related axes, there being a set of transducers for sensing such flexure and providing a coordinate-related signal to apparatus to be controlled, the control device having a depress mode in which the actuator button is axially depressed for actuation of a switch and thereby providing an alternate controlling function. Overload mechanism including a spring loaded articulated connection between the actuator button and the flexible bar mechanism limits the degree of flexure which can be imparted to the flexible bar mechanism by movement of the actuator button in any lateral direction from its neutral position to prevent damage to the sets of transducers.

Abstract: A switch assembly according to the present invention for operating a television game machine comprises a base member provided with a through hole, an operating rod extending through the through hole and pivotally supported by the base member, a plurality of automatic-reset switches operated by receiveing a pressing force from the operating rod when the rod is pivoted, a spring for returning the operating rod to its position before pivoting and a plate disposed on the base member and rotatable about the axis of the through hole. The plate has a hole, through which the operating rod extends. The hole is defined by a hole edge portion for regulating the range of the pivotal movement of the operating rod so as to permit the operation of either one switch when the plate is set at a specified position and to permit the operation of either one or two adjacent switches when the plate is located at another position.

Abstract: A control member which includes two or more pivoting ball members, one seated in a housing, and the others pivotally seated within an operational control stick integral with the first ball member. Each ball member includes a plurality of contacts with leads which extend to various operational controls. Upon touching of the ball contacts with an electrical source, current is transmitted to the operational controls to perform various operations.

Abstract: A manipulandum contained in a portable housing unit adapted for grasping by hand and situated at one end thereof within an area reachable by the thumb without rearranging the grasp. In one preferred embodiment, the manipulandum is a joystick extending a short distance from the surface of the housing, with its center of neutral position being essentially perpendicular to the center line of the elongated segment in the neighborhood of the joystick. The joystick has a fixed number of positions, with each position being contained within a preselected solid angle. An additional control dimension is realized by moving the joystick along its axis, against a resilient spring, so as to activate or make contact with an electrical switch.

Abstract: A control mechanism comprising a casing, an operating lever (1) projecting at the top from the casing and arranged to swivel omnidirectionally against a spring-produced resetting force, and at least two transducers arranged according to two orthogonal axes for producing signals being a measure for the magnitude of the swivelling angle and for the swivelling direction of the operating lever (1).The operating lever (1) is mounted near its lower end in a ball joint (2) received in the upper wall of the casing, with the free lower end of the lever (1) abutting on four spring elements (3,6,9,12) whose lines of action (X,Y) coincide two by two intersect each other at right angles. The spring elements (3,6,9,12) are connected at the lower end of the operating lever (1) to downwardly extending oscillating or wagging plates (5,8,11,14) whose ends (A,B), upon swivelling movement of lever (1), are displaced inwardly in the direction of the axis of the casing.

Abstract: A lever is carried in a holder that permits the lever to be pivoted in a complete circle to permit up/down and left/right movement or any position in between. The lever engages a carriage which carries electrical contacts. Movement of the carriage by the lever causes the electrical contacts to move to be able to engage selective electrical paths.

Abstract: A wind-controlled spraying apparatus is arranged to contain electrical contacts and essential mechanical parts within a single housing and to provide switching contacts on a printed circuit board designed as part of a control circuit for the spraying apparatus. The apparatus includes a nozzle that sprays insecticides into the wind for predetermined periods of time in response to changes in wind direction indicated by a wind-blown conducting tube that contacts only one of the switching contacts on the printed circuit board at any time.

Abstract: An apparatus is disclosed with which a graphics designer can select an exact color to be shown on a video display device. The apparatus includes a control element movable in a region having at least two geometrical dimensions, each position in the region corresponding to a different color. If the region is only two-dimensional, the color element position defines two of the three independent variables needed to define the desired color, and the third is controlled independently.

Abstract: A hand control capable of suppressing tremors and other unwanted vibrations is disclosed which incorporates viscous damping in two degrees of freedom to mechanically filter the forces applied by the user's hand. To suppress pathological intention tremors, the damping characteristics are chosen so as to selectively reduce the amplitude of movements at or above about 3 Hertz. The hand control includes a chamber filled with a viscous fluid, a position-sensing actuator assembly and a damping element connected to the actuator and disposed within the chamber to suppress involuntary movements of the actuator. The volume of the chamber, size of the damping element and viscosity of the fluid are chosen to achieve a damping constant of about 2 to 20 lbf-sec/ft., preferably from about 5 to about 15 lbf-sec/ft. The viscous fluid is preferably a silicone oil having a viscosity of about 300,000 to about 900,000 cstokes.

Abstract: An apparatus for exercise has a frame structure for hand holding standing up on a restrained universal mount fixed on a platform. A coil spring in compression and a stretched elastic cord laced around in tension restrains the universal mount providing adequate force for restoring the frame structure to its normal vertical position except as the user of the device deflected from that position. A two-axis sensor at the pivot center within the universal mount provides electrical inputs to a computer game programmed for video display. The position of the structure determines the direction of activity and the deflection specifies the amount of exertion input within the framework of a computer program for simulation of any of a variety of existing and new sports. The characteristics of the universal mount offer the player a challenge in terms of muscular strength, coordination and body balance.

Abstract: At a control signal generator for generating a pair of control signals by means of a control stick (10) deflectable in two directions a disc (22) is attached to the control stick (10) about its pivot mounting (12). Approach sensors (18) are located in a base portion (10) and respond to the motion of the disc (22) about the pivotal point (14) of the control stick (10). This results in a compact arrangement with contactless pick-offs, which are not subject to wear and which cannot be mechanically damaged even with rude operation.

Abstract: A contactless electric control handle having a field coil for forming an electro-magnetic field, inductive pick-up coils angularly spaced apart around the axis of the field. The rod of the control handle constitutes the core of the field coil. The field coil and the pick-up coils have the shape of annular, concentric conductors, whereas ferrite is applied to the rod in order to employ high frequencies up to 1 MHz.

Abstract: An analog proximity detector manipulator comprising, in a case with which are associated an electronic case containing the detectors and a piece for fixing to a table, a sub assembly containing an annular elastomer part which serves for pivoting and bringing back to the neutral position the control lever and a mass whose position influences the detectors.

Abstract: The invention relates to a switching device (coordinate switch), in which four switches are actuated by displacement of an actuation member in two orthogonal directions and a fifth switch is actuated by displacement in a direction at right angles thereto.

Abstract: A multi-direction joystick device has an operation shaft swingable in plural directions. The operation shaft has switch-pushing arm portions extending radially from the shaft and returning elastic plates also extending radially beyond the tips of the arm portions in separation from the arm portions.

Abstract: Disclosed herein is an improved joy stick control including a control rod interrelated with four switches so as to enable the control of movements in eight different directions. In a further aspect, the present invention includes a fire button located below the switches associated with the control rod and above indentations formed in the handle for the fingers. Each of the switches associated with the control rod includes a stationary upper contact and a movable lower contact with the lower contacts of the switches being operatively connected to the control rod.

Abstract: A joystick having a casing, a pair of gimbal plates mounted in the casing each slidable orthogonally with respect to the other and a pair of transducers, a control member of each coupled to a corresponding gimbal plate. A handle is coupled to the casing having a gimbal actuating sphere engaging each of the gimbal plates with the handle being universally pivotal throughout a portion of a spherical arc whose center lies intermediate the actuating sphere and an opposite end of the handle. Movement of the handle results in corresponding movement of the gimbal plates by an amount proportional to the component of displacement of the handle along the direction of movement of each of the gimbal plates. Each gimbal plate is biased so that it is urged towards a neutral position in the event of displacement on either side of the neutral position. External contacts are coupled to the transducers to allow the joystick to the electrically coupled to an external electrical line.

Abstract: In a manual digit data input device, including a set of cups configured to captivate the distal phalanges of a human hand; a housing; apparatus resiliently mounting the cups in the housing for mutually orthogonal transverse movements of the cups; and control apparatus actuated in response to movement of the cups.

Abstract: A joystick attachment for a computer keyboard which includes a bracket on which is supported a housing for a joystick assembly, the bracket being detachably mounted on a computer keyboard having a plurality of keys arranged in a rectangular array with the joystick assembly in over lying, spaced-apart relationship with the array, the joystick assembly including an upstanding handle projecting upwardly through an opening in the housing and supported on the bracket for universal pivotal movement together with a plurality of circumferentially spaced actuating arms each operatively associated with one of said keys and movable selectively by the handle against a yieldable member from an inoperative position into an operative position into an operative position for depressing engagement by the arm with an associated key in the array.

Abstract: A position sensor for producing a variable electrical output signal in response to manipulation of a quadrant lever or the like. A pair of tubes of equal length made of magnetically saturable material are secured to a frame in parallel proximity to a sheet-like permanent magnet which is mounted on a carrier. The magnet has a pair of active angled edges and the tubes are oriented to transversely intersect the respective angled edges, being so spaced from one another that the tubes are magnetically saturated over complementary fractions of their length. Each tube is engaged by at least one turn of wire and a detector circuit is provided having its input connected to the turns of wire for producing an electrical output signal in accordance with the differential magnetic saturation of the tubes. Each tube is angled generally transversely with respect to the direction of relative movement.

Abstract: A device which, when manually operated, will automatically return to an original position wherein a manually-operated control lever rotates at least one shaft having an arm mounted on the end of the shaft, and with a roll at the other end of the arm which abuts against one of two profiled parts when the shaft is rotated by the control lever. The two profiled parts resiliently abut a stop or stops when the arm is in an original or zero position but one profiled part abuts a stop while the other profiled part resiliently abuts the roll on the end of the arm when the shaft is rotated, and the profiled parts have steps thereon which are position markings able to be sensed manually by the control lever by a snap effect.