FR2514166A1 - CONTROLLED LEVER DEVICE WITH PERFECTED CENTERING MECHANISM - Google Patents

Abstract

THE INVENTION RELATES TO A CENTERING MECHANISM INTENDED FOR A CONTROL LEVER DEVICE. THIS MECHANISM INCLUDES A FIXED PLATE 12 WHICH HAS A SURFACE 20 SPACED BY A POINT OF ARTICULATION SHAPED AT THE INTERSECTION OF TWO TRANSVERSAL AXES 15, 16 ON WHICH A HANDLE 11 CAN SWIVEL. A CAM TRACKER 22 CAN SLIDE ON THE HANDLE 11 AND IT HAS A CONICAL SURFACE 23 WHICH COOPERATES, UNDER THE ACTION OF A RETURN SPRING 24, WITH A SURFACE OF AN OPENING THROUGH PLATE 12, IN ORDER TO CONSTANTLY TEND TO RETURN HANDLE 11 TO CENTERED POSITION. FIELD OF APPLICATION: CONTROL OF SEVERAL DEVICES USING A SINGLE LEVER.

Description

The invention relates generally to control levers of the

type with a handle that

  can be rotated on two distinct axes, oriented transversally

  badly to the longitudinal axis of the shaft, and more particularly

  an improved mechanism to exert restoring forces towards the center on levers of

handle type control.

  Two-axis swivel handles or levers are used as switch or valve actuators in various applications in which it is desirable or necessary to have several independent functions controlled by a

  unique lever Examples of such applications

  take control of the angle of attack and the

  blades, scrapers, cutting elements, etc. equipping earth-moving and snow-removing machines, controlling various wing profile surfaces on aircraft, controlling the position of a cutting tool in multi-axis machine tools, and controlling the position of an electron beam in various types of electronic instruments There are also many other applications and types of applications and the number of control devices to

  lever used in these applications continue to increase

Menter.

  The proliferation of devices requiring levered control devices has imposed increasingly stringent criteria on the characteristics of such devices.

  control devices These must function

  reliably for a long time At the same time, the manufacture and sale of such devices

  order are subject to significant competition.

  It is therefore necessary that any lever-operated control device used in large quantities is designed to be manufactured in a simple manner. Among other things, the cost limitation essentially imposes a design

  using a minimal number of easily assembled parts.

  In general, compliance with this criterion also leads to

  improved reliability and ease of operation

  because a simple design, using fewer parts, is normally less prone

  and easier to repair in case of failure.

  It is also desirable that a lever control device is designed to be readily adapted to various switches, electronic devices with proportional output signals, and / or valves. The adaptation to such devices is facilitated by a maximum increase, at a minimum. inside the control device,

  space that is not engaged for other characteristics

  necessary for the control device such as lever handle mounting elements to allow its pivoting movement and for recalling the neutral handle At the same time as it is desirable to maximize the free space, there is a constant need

  to reduce the global dimension of

  lever, and in particular to reduce the depth of these control devices and the distance on which they extend behind structures on which

they went up.

  Known means for mounting a control lever handle on a fixed support plate so

  that it can pivot on two transverse axes

  ball and socket devices and fixtures

  with gimbal suspension It is traditional to mechanize

  the recall function of a joystick in posi-

  by means of pairs of torsion springs or torsion springs operating in opposition, together with suitable levers and / or suitably disposed abutments A possible drawback of the use of torsion or traction springs is that the ends these springs often have relatively sharp bends that can form hooks or legs. These elbows are subject to the appearance of high stress points at which a failure may occur. Thus, reliability can be improved by avoiding the use of torsion springs. and / or traction Another disadvantage of the conventional device described above is its relatively high number of

  parts, because it is necessary in general, for each pivot axis-

  two springs and the associated levers and stops.

  Another feature of the control lever centering mechanisms which use pairs of opposing return springs is that the return force varies with the direction in which the control lever is tilted.

  ratio of force to displacement is greater when

  that the control stick is tilted in directions between the axes on which the return springs are aligned than when rotated in alignment

with the return springs.

  The use of traction springs is avoided in a joystick device designed as described in US Pat. No. 3,666,900. This patent generally relates to

  a cam structure comprising a fixed-guide plate

  and an indexing ring that can slide along the handle of a control arm and which is recalled against

  the guide plate by means of two compressor springs

  It is suggested that certain embodiments in which the guide plate is profiled so as to momentarily actuate the control arm. In this device, the momentary actuating mechanism and the switches actuated by the control arm are placed.

  on the same side of the joint arm pivot point

  Thus, it is necessary to provide a large space for the indexing ring so that it can move towards the point of articulation when the control arm is moved away from its centering position.

  relatively deep configuration.

  U.S. Patent Nos. 3,639,705 and 4,206,602 each disclose a control lever device having certain structural similarities with the device described in the aforementioned US Pat. No. 3,666,900. device uses a ring slidable along a handle of the control lever, the ring is used only for snapping or indexing purposes so

  to maintain a desired position of the control lever.

  The invention relates to a particular mechanism for returning a lever control device in position which maintains the same positioning force ratio irrespective of the direction in which the control stick is tilted. This characteristic is obtained by means of a design device. extremely simple and using a minimum number of parts The restoring forces in all directions are produced by a single spring

  compression which cooperates with a simple assembly to

  cam face and cam follower, placed on the side of the hinge point opposite to that of the devices that are actuated by the control handle The return mechanism in position is extremely compact, allowing

  thus a low profile configuration that increases the maximum

  mum the space offered to the switches, etc., and, moreover,

  extends a minimum distance behind the structure

  on which the control device is mounted.

  The invention therefore relates to a return mechanism in position of a control lever, simple and compact, comprising a control stick which is mounted in a fixed plate so as to be pivotable about two axes oriented transversely to the handle, in a hinge point located thereon, and having a cam follower mounted to move along the handle A spring is for biasing the cam follower toward the hinge point, and the fixed plate has a configured cam surface and

  positioned to cooperate with the cam follower for the purpose of

  The cam surface and a complementary surface provided by the follower can form symmetrical surfaces of revolution about the handle, and the spring can be a spring. of compression surrounding the handle between the cam follower

  and a fixed retention member mounted on the handle.

  The invention will be described in more detail with reference to the accompanying drawings by way of non-limiting example and in which: FIG. 1 is a perspective view, partly in section, of the control lever device comprising a return mechanism in position; according to the invention; Figure 2 is a partial axial section of the lever control device of Figure 1, the handle is in a centered position; Figure 3 is a partial axial section of the control lever device of Figure 1, the handle is tilted to a position of extreme distance from the centered position; FIG. 4 is a plan view of a plate

  mounting device used in the joystick device

  Figure 1, and showing an opening through

  this plate and a cam surface formed thereon; and FIG. 5 is a partial section, on an enlarged scale, along the line 55 of FIG. 4, of a detail

  of the plate shown in FIG.

  In FIGS. 1 to 3, the reference numeral

  10 designates the control lever device according to the invention.

  which includes a control handle 11 mounted

  able to pivot on a fixed structure

  a plate 12, by means of a gimbal suspension indicated generally by the reference numeral 13. The handle 11 extends along a longitudinal axis 14 and

  can rotate about two axes 15 and 16 which are

  felt to be orthogonal and transverse-oriented

  axis 14 and which define a point of articulation

  In Figures 2 and 3, the hinge point is identified by the numeral 17. The plate 12 has an upper surface or face 18 which is spaced along the axis 14 of the

  point 17 of articulation The plate 12 is also traversed

  The opening 19 is circular and symmetrical about the axis 14 when the handle 11 is in its central position. cam surface is formed on the periphery

  of the opening 19 at its intersection with the surface 18.

  As shown in FIGS. 4 and 5, the cam surface 20 is configured so that its radial section with respect to the axis 14 has the shape of a circular arc. A cam follower 22 or countercam, in the form of a sleeve having a conical surface 23, is mounted on the handle 11 in order to slide along the axis 14 The surface 23 is a surface of revolution around of the axis 14 The cam surface, which is also illustrated in the form

  of a surface of revolution, is configured and position-

  born to cooperate with the conical surface 23 which is substantially on the side of the plate 12 opposite to that

of articulation point 17.

  A coil spring 24 surrounding the handle is compressed between the cam follower 22 and a retaining element attached to the handle 11. The spring 24 constitutes a biasing element which recalls or tends to move the cam follower 22 towards the point 17 of the cam. As a result, the spring 24 tends to accommodate the cam follower 22 in the opening 19 to place the handle 11 in a centered position. The cam surface 20 allows the cam follower 22 to move as far as possible or to arrive at the cam follower 22. a minimum distance from the articulation point 17 when the handle 11 is in the centered position As shown in FIG. 3, when the handle 11 is pivoted away from the centered position, in any direction transversely oriented to the 14, the cam surface has the effect of moving the follower 22 from the hinge point 17 against the force of the spring 24. Inversely, the spring 24 tends in conjunction with the cam follower 22 and the cam surface 20. bring back the 11th round

the centered position.

  The cardan suspension 13 is an example of a type of mounting device for pivotal movement on two transverse axes. It comprises a ring 30 which can pivot on the handle 11 by means of suitable pins 31 aligned on the axis 16 The ring 30 can also pivot on the plate 12 by means of brackets 32 which are fixed to the plate 12, and suitable pins 33 aligned on the axis 15 and carrying the ring 30 so that it can pivot between the brackets 32 Therefore, the handle 11 can pivot independently about the axes 15 and 16 However, it should be noted that, although a cardan suspension support is shown, other types of supports

  such as a ball and socket

be used.

  The control lever device 10 is generally used to actuate several switches,

  valves, etc. in order to control several independent functions.

  hanging from a single manual control lever.

  Therefore, in a typical installation, the

  upper handle 11 is equipped with a suitable handle, and its lower end is designed to actuate switches, valves, etc. A suitable mechanism to allow the actuation of some,

  chosen, of several switches is illustrated globally-

  1 to 3 This arrangement comprises a particular mechanism for converting a pivoting movement of a handle into a movement in a plane, and it is the subject of the French patent application filed on September 23, 1982 under the number 82 16027,

  We can refer to this request for a description

  of the mechanism of motion conversion Cepen-

  the following brief description provides a better understanding of

  take the operation of the present invention.

  The reference numeral 34 identifies a structure

  support structure which is fixed to the plate 12 by means of several screws 35 passing through countersunk holes 36 shown in FIG. 4. The structure 34 is traversed by an opening 37 through which the lower extremity passes.

  of the sleeve 11 The structure 34 also has an over-

  lower face 38 which is shown as a flat surface A retainer 39 having a

  flat upper surface, is mounted on the structure 34-

  from which it is spaced by several colonists

  40, so as to define a cavity with surfaces

  parallels between the structure 34 and the retaining element 39

  naked A disk 41 is mounted in this cavity The disk

  comprises a flexible central core 42 having an opening

  to narrowly receive the end of the handle 11, and an extra-thick rim 43 with parallel sides and having a thickness slightly less than the distance between the structure -34 and the retaining element 39. As shown in FIG. pivoting of the handle 11

  around the articulation point 17 is converted into a

  in a plane of flange 43 because of its connection

  with the shaft 11 via the soul 42.

  Several switches 44 are mounted on the

  support structure 34 around the disk 41.

  The actuators 44 are arranged such that their actuators, which may include levers and / or plungers, can be displaced by the flange 43. As a result, one or more desired switches 44 can be actuated by pivoting the handle 11 in one direction.

appropriate.

  It follows from the previous description that

  in accordance with the invention, a particular mechanism for returning a control lever to a position is obtained,

  simple and compact, with a consistent characteristic

  aunt force-in-function of movement, regardless of the direction in which the joystick lever

is switched.

  It goes without saying that many modifications can be made to the mechanism described and shown without departing from the scope of the invention. For example, the cam surface and / or the complementary surface presented by the cam follower can be modified to vary the displacement force demanded as a function of displacement, or the surfaces can be configured otherwise than in the form of surfaces of revolution for

  that various relationships of force be

  displacement in the direction of movement of the

control stick.

-

Claims (1)

CLAIMS 1 Device with a control lever of the type in which a control lever handle (11) is mounted in a fixed structure in order to be able to pivot about two distinct axes (15, 16) oriented transversely to the longitudinal axis (14) of the handle, at a point (17) of articulation located on the latter, the device being characterized in that it comprises a de-centering mechanism comprising a fixed plate (12) having a surface (20) located at a point along the longitudinal axis, spaced from the articulation point, said fixed plate being traversed by an opening (19) in which the handle passes, a cam follower (22) being mounted so as to slide on the handle, at a point generally on the side of the surface of the fixed plate opposite that of the hinge point, the cam follower being configured to cooperate with the surface of the fixed plate presented by the opening through which the in order that a movement of the cam follower towards the articulation point has the effect of accommodating this follower in the opening in order to establish a centered position of the handle, and so that a pivoting of the handle away from the centered position forcibly slides the cam follower along the handle away from the articulation point, means (24) for biasing the cam follower back along the handle towards the cam. point of articulation. 2 Apparatus according to claim 1, characterized in that the cam follower has a conical surface (23) which moves on the surface presented by the fixed plate at the periphery of the opening therethrough. 3 Device according to claim 2, characterized in that the opening through the fixed plate is circular. 4 Device according to one of the claims   1 and 3, characterized in that the return means   take a coil spring (24) surrounding the handle and 1 1 tablet between the cam follower and an element (25) of retainer mounted on the handle.   Device according to claim 1, characterized in that the handle is rotatably mounted by means of a universal joint (13).