REMOTE CONTROL MECHANISM

Abstract: A remote control mechanism has a gear lever 1 pivotable about mutually perpendicular axes 2 and 3 of which the latter is the longitudinal axis of a torque tube 19. When pivoted about the axis 3, the gear lever will rotate the torque tube 19 about its axis and cause, via a lever arm 23, a translational movement of the core 26 of a short push-pull cable 27 to effect a rail select movement of a gear select and shift finger. When the gear lever 1 is pivoted about the axis 2, an arm 7 fast with the gear lever will translate the core 8 of a relatively long push-pull cable 9 to cause the finger to shift the selected rail and so effect a gear change. The point of interconnection 10 of the core 8 with the arm 7 will make arcuate movement about the axis 3 of the torque 19 when the gear lever is pivoted about that axis in the rail select mode, and such arcuate movement will tend to cause unwanted rail shift translation of the core 8 with attendant possible baulking of the gear change system. To overcome this problem, the casing 11 of the cable 9 is made rotationally fast with the torque tube 19 by means of a rigid member 12 in which the cable casing is mounted and clamped against movement and to which the torque tube is affixed. Thereby, when the torque tube 19 is rotated by a rail select pivotal movement of the gear lever 1, the rail shift cable 9 will bodily move through the same arc of movement as the interconnection 10 between the cable core 8 and the lever arm 7 so obviating the undesirable tendency of the cable core to make an unwanted rail shift translation.

Description: This invention relates to remote control mechanisms. A remote control mechanism is known having a control member pivotable about mutually displaced axes to effect through a pair of control links different modes of operation of a controlled device. Specifically, the controlled device may be a gear change device of a manual change gear box with the control member being a gear lever which when pivoted about one axis displaces one of the control links to effect a rail select movement of the gear change device and which when pivoted about the other of the mutually displaced axes displaces the other of the control links to effect a shift movement of the selected rail thereby to change gear. Whilst the aforesaid pivotal movements of the gear lever should operate only one of the control links at a time, in the aforesaid known remote control mechanism, when the gear lever is pivoted to effect through said one control link a rail select movement of the gear change device the other control link is caused at the same time to make a small degree of unwanted operational movement which could cause the gear change system to baulk. In fact, a skilled driver would feel resistance in the system against such movement and would take remedial action by urging the gear lever in an arcuate transverse path considered in plan, rather than straight across the "gate", to compensate for such unwanted operational movement. However, the onus is entirely on the driver to prevent the described unwanted operational movement. In GB-A-342718 there is generally disclosed a remote control mechanism comprising a control member movable in different control modes, a first control link means in the form of a torque tube interconnected with the control member such as to be caused to make a first, rotational control movement about its longitudinal axis in response to the control member being moved in a first one of its said control modes, and a second control link means interconnected with the control member such as to be caused to make a second control movement in response to the control member being moved in a second one of its control modes, movement of the control member in its first control mode resulting in movement of the interconnection of the second control link means with the control member. More particularly, the aforesaid second control link means takes the form of a rod which is connected by a ball and socket joint at one end to a first arm fast with the control member, the opposite end of the rod being connected by a second ball and socket joint to a second arm which is fast with a rotatable actuating shaft carrying a gear selector lever. Further, the end of the torque tube distal from the control member carries a third depending arm having a pin engaging freely in a slot formed in the second arm with which the actuating shaft is fast. When the control member is moved in its first control mode so rotating the torque tube, the third arm rotates with the torque tube to cause, via the engagement of its pin in the slot of the second arm, the actuating shaft to slide longitudinally so effecting a gear select movement of the selector lever. When the control member is moved in its second control mode, the rod is moved in a longitudinal direction by the first arm and the associated ball and socket joint, and this movement is transmitted by the ball and socket joint at the opposite end of the rod to the second arm thereby to rotate the actuating shaft and so cause the selector lever to make a gear shift movement. The first control mode of movement of the control member will not only rotate the torque tube but, via the first arm and the ball and socket joint connection to the rod, also rotate the end of the rod proximal to the control member. Moreover, via the third depending arm, the engagement of the pin in the slot of the second arm, and the ball and socket joint connection between the second arm and the end of the rod distal from the control member, such movement of the control member in its first control mode will also rotate that distal end of the rod. Unless the proximal and distal ends of the rod are rotated through the same arcs, the rod could make unwanted longitudinal movement effecting a gear shift movement of the selector lever even though the control member had been operated in its gear selector mode. In accordance with the present invention as claimed, the aforesaid generally disclosed remote control mechanism of GB-A-342718 is characterised in that the second control link means comprises a cable having a core axially translatable within a casing, the cable core being interconnected with the control member such that the cable core is axially translated within the casing to make the second control movement in response to the control member being moved in its second control mode, and in that a means is provided interconnecting the torque tube with the cable casing to cause the cable to move with the torque tube as the torque tube is caused to make its said rotational movement in response to the movement of the control member in its first control mode by which to compensate for the movement of the interconnection of the cable core at that time which otherwise could result in unwanted translational control movement of the cable core. When the remote control mechanism of the present invention is applied to a gear change device as hereinbefore first described, the tendency of said other control link to make an unwanted degree of rail shift movement, when the rail select control link is operated, is obviated with the attendant advantage that any possibility of the gear change device to baulk in the event that the driver not taking remedial action is removed. Thus the invention has the advantage that it solves the problem posed by the aforesaid known remote control mechanism first described in a particularly simple manner. In the same aforesaid known remote control mechanism, the control links are constituted by a flexible two cable unit. Such cables run from the gear lever to the gear box area and their lengths can be considerable as well as involving a number of bends in the cable. Also, the two cable unit is fixed to the floorpan of the vehicle, and there can result noise transmission from the gear box to the passenger compartment. In an embodiment of the invention at present preferred, a remote control mechanism employs a control member in the form of a gear lever which when pivoted about one axis to cause a rail select movement of the gear change device rotates the torque tube which is taken from the gear lever vicinity into the gearbox area at which is it supported by a convenient part of the vehicle chassis, for example the engine/gearbox subframe. That end of the torque tube is connected by a relatively short flexible cable or rod to the gear change device such that rotation of the torque tube will translate that cable core or rod to effect a rail select movement of the device. The gear lever is also connected by the second control link means taking the form of a relatively long flexible said cable to the gear change device so that pivotal movement of the gear lever about another axis displaced from said one axis is transmitted directly by that flexible cable to the gear change device to effect a shift movement of the selected rail. The operative interconnection of the gear lever with the relatively long rail shift cable is such that when the gear lever is pivoted to effect through the torque tube a rail select movement, the end of the core of the rail shift cable at that operative interconnection is rotated out of the line of action of the cable, and hence relative to the fixed proximal end of the casing of the rail shift cable. As such, there would be a tendency for the core to be translated within the cable casing, and this tendency is eliminated by clamping the casing of the rail shift cable, at a point spaced from the interconnection of the gear lever with the cable core, to the torque tube so that the rail shift cable as a whole will be bodily rotated with the torque tube through the same degree of angular movement as the end of its core interconnected with the gear lever. Also, with the described construction of that preferred embodiment, the aggregate length of the flexible cable run is reduced since the length of the rail select cable is able to be minimised and the transmission of noise from the gearbox area is also reduced by supporting the distal end of the gear select linkage, specifically the torque tube, by the engine/gearbox subframe. Whilst the invention is described specifically herein in the environment of use as a gear changer, it is to be understood that it is not limited to that environment but has other applications involving the control of a controlled device constituted by a single or more operating members of which different movements can be induced by a single lever control. In order that the invention may be well understood there will now be described two embodiments thereof, given by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic representation of a preferred gear change system; and Figure 2 is a schematic representation of an alternative gear change system. In the two figures, like parts are denoted by like references. Referring first to Figure 1, a gear lever 1 is pivotable about mutually perpendicular axes 2 and 3. The lower end of the gear lever 1 is mounted in a block 4 which is affixed to another block 5 by a pivot pin 6 so that the block 4 and hence the gear lever can be pivoted relative to the block 5 about the transverse axis 2, which is the longitudinal axis of the pivot pin. From the lower end of the block 4 depends an arm 7 which is fast with the block and which is attached to the core 8 of a flexible push-pull cable 9 by a pivot pin 10 parallel to the pivot pin 6. The end of the cable 9 proximal to the gear lever 1 has its casing 11 mounted and clamped against movement in the lower part of a rigid member 12. At the distal end of the cable 9 which runs to the vicinity of the gearbox, the cable casing 11 is held in a member 13 mounted to the engine or gearbox against translational movement and its core 8 is suitably operably attached to a lever 14 affixed to a vertical rail shift shaft 15. As shown, the core 8 has a hooked end 16 which is hooked into a vertical aperture 17 in the lever 14 so that translation of the core effects, via the lever, rotation of the shaft 15 about its longitudinal axis 18. With the arrangement as so far described, manual pressure in a fore or aft direction applied to the gear lever 1 to cause it to pivot about the transverse axis 2 will translate the core 8 of the flexible cable 9 in a push or pull mode (depending on the sense of pivotal motion of the gear lever) to rotate the shift lever 14 and so the rail shift shaft 15 in an attendant sense to cause a gear select and shift finger (not shown) to shift the selected rail and so effect a gear change through a mechanism which is not illustrated but which can take any of a number of different known constructions and which need not be further described here since it forms no part of the present invention. Describing now the rail select structure, the block 5 is mounted upon and is fast with a torque tube 19, which may take the form of a solid rod, running lengthwise of the vehicle. The torque tube 19 has its end proximal to the gear lever 1 journalled for rotation in a bearing block 20 which is affixed by studs 21 to the underside of the floorpan (not shown) of the vehicle. The distal end of the torque tube 19 runs to the vicinity of the gearbox and is mounted for rotation in a bracket 22 which itself is mounted to a convenient vibration isolated part of the vehicle chassis such as the engine/gearbox subframe (not shown). Alternatively or additionally, the required degree of vibration isolation could be provided by mounting the torque tube 19 via a rubber bush in the bracket. Between its proximal and distal ends, the torque tube 19 extends through and is affixed to the upper part of the rigid member 12 supporting the flexible cable 9. To the distal end of the torque tube 19 is made fast a lever arm 23 which has a horizontal aperture 24 into which hooks the bent end 25 of the core 26 of a short flexible push-pull cable 27. The casing 28 of the cable 27 in its region proximal to the lever arm 23 is clamped against translational movement in a member 29. The member 29 is mounted upon a steering rack arm S of the vehicle which is supported by the bracket 22 to the aforementioned subframe. At the opposite end of the short run of cable 27, its casing 28 is clamped against translational movement and mounted in the member 13 which thus maintains the distal end of the long and short cables 9 and 27, respectively, in mutually spaced relationship. Also, the core 26 has a bent distal end 30 which is hooked into a horizontal aperture 31 in a rail select lever arm 32 affixed to a horizontal rail select shaft 33. When transverse manual pressure is applied to the gear lever 1, the torque tube 19 will rotate about its longitudinal axis 3 within the bearing block 20 and the bracket 22 with the result that the lever arm 23 will rotate to translate the core 26 of the cable 27 which, via the lever arm 32, will rotate the rail select shaft 33 about its horizontal axis 34 in a sense dependent upon the direction in which the gear lever 1 is transversely pivoted. Such rotation of the rail select shaft 33 will cause the gear select and shift finger to make a rail select movement again through a mechanism which is not illustrated but which can, as before, take a number of different forms which need not be further described here since it forms no part of the present invention. With the described mechanism, the gear rail select and shift functions are effected independently of one another. In practice, the driver would, of course, pivot the gear lever 1 transversely into the appropriate rail select mode and then pivot the gear lever fore or aft to effect the required rail shift to effect a gear change. As illustrated, the driver has five forward gears available as well as a reverse gear. An appropriate gate could be provided within which the gear lever 1 is movable, although this is not necessary where the construction of the gear box itself dictates the operational movement available to the gear lever. When the gear lever 1 is pivoted transversely about the longitudinal axis 3 to rotate the torque tube 19 and hence translate the core 26 of the rail select cable 27, the arm 7 will rotate in sympathy about that axis and, in consequence, tend to translate the core 8 of the rail shift cable 9 and cause the gear change system to baulk unless the driver, upon sensing the resistance to movement, takes remedial action by swinging the gear lever in an arc to one side of the central pivotal plane. Such unwanted motion of the rail shift cable 9 is eliminated, without any necessity for action on the part of the driver, by the provision of the rigid member 12 which will rotate with the torque tube 19 and so bodily move the rail shift cable in its casing region supported in the rigid member through the same arc of movement as the proximal end of the cable core 8 pinned to the arm 7. Loads in the short rail select cable 27 are reacted at the bracket 22 supporting the distal end of the torque tube 19 and hence are dissipated by the engine/gearbox subframe. Moreover, the torque tube 19 is axially fixed at its distal end only, its end proximal to the passenger compartment being free to slide axially in the bearing block 20. The effect of this is that "into-gear" loads imposed on the long cable 9 are also transmitted through the torque tube 19 into its fixed distal end and are, consequently, also largely taken by the engine/gearbox subframe. Therefore, by mounting the fixed, distal end of the torque tube 19 on a vibration isolated bracket and/or vibration isolated part of the vehicle chassis, the noise transmission to the passenger compartment both upon rail select and shift operations is reduced as also is the degree of noise transmission of the engine and gearbox. Again, since the proximal end of the torque tube 19 is free to slide longitudinally in the bearing block 20, there is compensation available for errors in the length of the torque tube or its mounting positions. If a cross gate position spring bias mechanism is to be provided, for example a 3/4 position bias, this can be situated at either end of the torque tube 19, thus reducing another possible source of noise which would otherwise be transmitted to the passenger compartment. With the torque tube 19 extending from the gear lever 1 to the gearbox area, the length/number of bends in the gear select cable 27 is/are able to be reduced, with consequent reduction in the amount of lost motion and drag. Whilst the proximal and distal ends of the short rail select cable 27 and the distal end of the long rail shift cable 9 are shown and described as being bent and hooked into apertures in the respective lever arms, it will be appreciated that other connections between the cable cores and lever arms are possible such as pinned connections permitting the necessary degree of relative pivotal movement between the lever arms and the cable cores. In an alternative arrangement where the lever arms 23 and 32 are juxtaposed, the short cable 27 could be replaced by a rigid link such as a rod. Referring now to Figure 2, an alternative gear change system is shown which, instead of comprising (as in Figure 1) a long torque tube 19 running from the gear change lever 1 to the vicinity of the gear box, there to have its distal end connected by the lever arm 23 to the short rail select cable 27, has a short torque tube 19 and a long rail select cable 27 running to the vicinity of the gear change lever 1. In this alternative construction, the lever arm 23 is made fast with the proximal end of the torque tube 19 and is suitably operatively interconnected with the proximal end of the core 26 of the long rail select cable 27. As shown, such interconnection could be provided by the lever arm 23 extending vertically downwards from the torque tube 19 to make operative interconnection via a sliding ball joint 36 with an input arm 37 of a horizontal bell crank lever 38 which is pivotal about a vertical pivot axis 39 and whose output arm 40 is operatively interconnected with the proximal end of the core 26 as by the bent end 25 of the core hooking into that output arm as shown or by a pinned connection being provided between the core 26 and the output arm 40. With the described alternative gear change system, when the gear change lever 1 is pivoted transversely in its rail select mode, the short torque tube 19 is pivoted about its longitudinal axis 3 as before to pivot the lever arm 23, and this lever arm via the sliding ball joint 36 will turn the bell crank lever 38 about its vertical axis 39 thereby to cause its output arm 40 to effect a rail select translation of the core 26 of the rail select cable 27. Whilst the bell crank lever 38 is shown as horizontal and pivotal about a vertical axis 39, it could be mounted in other orientations with the lever arm 23 orientated appropriately, provided the axis of rotation 39 passes through the longitudinal axis of rotation 3 of the torque tube 19. The proximal and distal ends of the short torque tube 19 together with pivot means (not shown) mounting the bell crank lever 38 for its pivotal movement could all be journalled in a common frame fast with the vehicle chassis to which frame the casing 28 of the rail select cable 27 at its proximal end would be clamped against movement. Other than the described modifications, the alternative gear change system illustrated in Figure 2 could have the configuration of the preferred Figure 1 system. Thus, the facility of the alternative system to prevent baulking due to the tendency of the rail shift cable 9 to translate when the gear change lever 1 is shifted in the rail select mode remains as before with the rigid member 12 swinging the cable 9 bodily as the torque tube rotates to compensate for the arm 7 swinging the proximal end of the core 8 out of the line of action of the rail shift cable at that time. The alternative gear change system would not, of course, possess the other described advantages of the preferred embodiment attendant upon the combination of a long torque tube and short rail select cable. As another alternative when used with a single shaft rather than the described double shaft gearbox, the rail shift cable 9 and rail select cable 27 (or rod) would be arranged selectively to operate that single shaft so as to rotate the shaft in one operational mode and translate the shaft in the other operational mode.

Claims: A remote control mechanism comprising a control member (1) movable in different control modes, a first control link means in the form of a torque tube (19) interconnected with the control member (1) such as to be caused to make a first, rotational control movement about its longitudinal axis (3) in response to the control member (1) being moved in a first one of its said control modes, and a second control link means (9) interconnected with the control member (1) such as to be caused to make a second control movement in response to the control member (1) being moved in a second one of its said control modes, movement of the control member (1) in its first control mode resulting in movement of the interconnection of the second control link means (9) with the control member (1), characterised in that the second control link means (9) comprises a cable (9) having a core (8) axially translatable within a casing (11), the cable core (8) being interconnected with the control member (1) such that the cable core (8) is axially translated within the casing (11) to make the second control movement in response to the control member (1) being moved in its second control mode, and in that a means (12) is provided interconnecting the torque tube (19) with the cable casing (11) to cause the cable (9) to move with the torque tube (19) as the torque tube (19) is caused to make its said rotational movement in response to the movement of the control member (1) in its first control mode by which to compensate for the movement of the interconnection of the cable core (9) at that time which otherwise could result in unwanted translational control movement of the cable core (8). A remote control mechanism as claimed in claim 1, wherein the interconnection of the cable core (8) with the control member (1) is spaced from the longitudinal axis (3) of the torque tube (19) such that movement of the control member (1) in its first control mode will not only rotate the torque tube (19) about its longitudinal axis (3) but will also rotate the cable core (8) at its interconnection with the control member (1) about the longitudinal axis (3) of the torque tube (19) which could result in a tendency for the cable core (8) to make its said unwanted translational control movement were it not for said means (12) interconnecting the torque tube (19) with the cable casing (11) by which said rotation of the torque tube (19) results in rotation of the cable (9), at the point at which its casing (11) is interconnected with the torque tube (19), through the same arc of movement as the cable core (8) at its interconnection with the control member (1). A remote control mechanism as claimed in claim 1 or claim 2, wherein the interconnecting means (12) interconnects the torque tube (19) with the cable casing (11) at a point spaced along the cable (9) from the interconnection of the cable core (8) with the control member (1), and wherein the interconnecting means (12) is a rigid member (12) in which the cable casing (11) is clamped against translational movement and to which the torque tube (19) is affixed. A remote control mechanism as claimed in any of the preceding claims, wherein the control member (1) is pivoted about a first pivot axis (3) when moved in its first control mode, and wherein the control member (1) is pivoted about a second pivot axis (2), which is angularly displaced from the first pivot axis (3), when moved in its second control mode. A remote control mechanism as claimed in claim 4, wherein the first pivot axis (3) and the second pivot axis (2) are mutually perpendicular. A remote control mechanism as claimed in claim 4 or 5, wherein the control member (1) is pivoted to means (4,5) fast with the torque tube (19) for pivotal movement about the second pivot axis (2) and with respect to the torque tube (19) when effecting translation of the cable core (8), and wherein the torque tube (19) is mounted for rotation in a pair of spaced bearing means (20,22) by which to rotate about its longitudinal axis (3) when the control member (1) is pivoted about its first pivot axis (3) which is the longitudinal axis (3) of the torque tube (19). A remote control mechanism as claimed in claim 6, wherein the end of the torque tube (19) proximal to the control member (1) is journalled for rotation in a first one of the bearing means (20) and is axially slidable therein, and wherein the end of the torque tube (19) distal from the control member (1) is mounted for rotation in a second one of the bearing means (22) and is axially fixed relatively thereto, by which axial loadings imparted to the torque tube (19) upon pivotal movement of the control member (1) about its second pivot axis (2) are reacted at the second bearing means (22). A remote control mechanism as claimed in claim 7, wherein the second bearing means (22) incorporates a vibration isolating means and/or is mounted on a vibration isolated part of the chassis of a vehicle. A remote control mechanism as claimed in claim 7 or 8, wherein the pivotal movement of the control member (1) about its first pivot axis (3) effects a rail select movement of a gear change device via the torque tube (19), and wherein the pivotal movement of the control member (1) about its second pivot axis (2) causes the cable core (8) to effect a rail shift movement of the gear change device. A remote control mechanism as claimed in claim 9, including a second cable (27) of which the core (26) at one end is operatively associated with the distal end of the torque tube (19) such that the core (26) will translate in response to the rotation of the torque tube (19) to effect the rail select movement. A remote control mechanism as claimed in any of claims 4 to 6, wherein the pivotal movement of the control member (1) about its first pivot axis (3) effects a rail select movement of a gear change device via the torque tube (19), and wherein the pivotal movement of the control member (1) about its second pivot axis (3) causes the cable core (8) to effect a rail shift movement of the gear change device. A remote control mechanism as claimed in claim 11, including a second cable (27) of which the core (26) at one end (25) is operatively associated with the torque tube (19) in the vicinity of the control member (1) such that the core (26) will translate in response to the rotation of the torque tube 19 to effect the rail select movement. A remote control mechanism as claimed in claim 12, including a lever arm (23) fast for rotation with the torque tube (19) in the vicinity of the control member (1) and operatively interconnected with an input arm (37) of a bell crank lever (38) which is pivotal about an axis (39) passing through the longitudinal axis (3) of the torque tube (19) and whose output arm (40) is operatively interconnected with said one end (25) of the second cable core (26).

Inventors: CRACK, DAVID JOHN
Applicants: MORSE CONTROLS LIMITED
Application year: 1989
Main classification: F16H63
IPC codes: F16H61, B60K20