Door latch mechanism operable via cables from multiple user controls

Abstract

An apparatus comprising a door, a door latch mechanism includes a latch release element 40 that is operable to release the door via two, preferably four, flexible cables 201 extending from a user cont

Description

Technical Field

[0001] This disclosure relates to mechanisms for selectively latching and releasing a door, for example a door of a vehicle, responsive to actuation of one of a plurality of user controls connected to the mechanism via cables. Background

[0002] Larger work machines such as excavators and other heavy off-road vehicles often have a cab located at a substantial height above ground level. The cab is accessed via a door that is secured by a door latch mechanism in a closed position, and often also in an open position. It is often necessary to provide at least two door latch controls for releasing the door latch, one inside the cab and another on the outside of the machine nearer to the ground. However, such arrangements can be complicated and expensive.

[0003] US5655798A teaches a work machine with a high cab having a door that can be latched in both closed and open positions. The latch mechanism is operable by a handle located on the door to be accessible in the closed position; by a pullrod with a knob accessible when the door is latched open; and by a lower handle accessible from ground level. The handles and pullrod are connected by a linkage with slots providing lost motion to reduce the force required to operate the mechanism.

[0004] US20080296914A1 discloses a latch mechanism for a work machine with a high cab, operable by rotating a lever. The lever is connected to the latch mechanism via a cable, and may be mounted on an upper or lower part of the door.

[0005] US10214945B2 discloses a vehicle door latch assembly having a release mechanism with levers operable by cables. Summary of the Disclosure

[0006] In accordance with the present disclosure there is provided an apparatus as defined in claim 1. The dependent claims define optional features.

[0007] The apparatus includes a movable door, a door latch mechanism for selectively retaining the door in at least one retained position, first and second user controls that are spaced apart in different locations, and first and second flexible cables, each having a proximal end and a distal end.

[0008] The door latch mechanism includes a support element and a latch release element movably connected to the support element. The latch release element is a single rigid assembly or body and is movable relative to the support element, in a release direction, from a rest position to a release position, to operate the door latch mechanism to release the door from the retained position.

[0009] The first user control is connected to the proximal end of the first flexible cable and movable by a user to apply a tension force to the first flexible cable.

[0010] The second user control is connected to the proximal end of the second flexible cable and movable by a user to apply a tension force to the second flexible cable.

[0011] Each of the first and second flexible cables is connected at its distal end to the latch release element to apply the tension force to the latch release element to move the latch release element, by the tension force, in the release direction from the rest position to the release position.

[0012] Lost motion is provided between the distal end of each of the first and second flexible cables and the latch release element.

[0013] In consequence, the first flexible cable is operable to apply the tension force to the latch release element to move the latch release element, by the tension force, in the release direction from the rest position to the release position, without movement of the distal end of the second flexible cable in the release direction.

[0014] Similarly, the second flexible cable is operable to apply the tension force to the latch release element to move the latch release element, by the tension force, in the release direction from the rest position to the release position, without movement of the distal end of the first flexible cable in the release direction.

[0015] For brevity, the latch release element will be referred to herein as the LRE. Brief Description of the Drawings

[0016] Further features and advantages will be appreciated from the illustrative embodiments which will now be described, purely by way of example and without limitation to the scope of the claims, and with reference to the accompanying drawings, in which:

[0017] Fig. 1 shows a vehicle with a cab door latch mechanism operable by four user controls, in accordance with an embodiment. Fig. 2 shows the four user controls. Figs. 3 and 4 show the first user control, respectively in the idle position and the release position. Fig. 5 shows the cab door retained in the closed position. Fig. 6 shows the cab door retained in the open position. Figs. 7-16 show the latch mechanism, wherein: Fig. 7 shows the LRE in the idle position (Pl) with the door released. Fig. 8 shows how the staple rotates the striker as the door moves towards the retained position. Fig. 9 shows how the LRE moves back to the latched position (P2) to retain the door as the door reaches the retained position. Fig. 10 shows how the first user control moves the LRE to the release position (P3). Fig. 11 shows how the striker rotates to release the door when the LRE reaches the release position (P3). Fig. 12 shows how the LRE returns to the idle position (Pl) as the user control also returns to the idle position after releasing the door. Fig. 13 shows how the second user control moves the LRE to the release position (P3). Fig. 14 shows how the third user control moves the LRE to the release position (P3). Fig. 15 shows how the fourth user control moves the LRE to the release position (P3). Fig. 16 shows the LRE in the idle position (Pl), the latched position (P2), and the release position (P3). Fig. 17 is an enlarged view of part of the LRE as shown in Fig. 16, illustrating how the distal end portion of the cable lies between the arcs described by the motion of the bounding surface of the cable aperture. Fig. 18 shows the LRE with the bushes assembled into the primary component, but without the flexible cables. Figs. 19 and 20 are respectively, front and rear views of the primary component of the LRE, before the bushes are inserted into the primary apertures. Figs. 21-23 show the terminal body fixed at the distal end of one of the cables. Figs. 24 - 29 show one of the bushes, wherein: Fig. 24 is a front end view. Fig. 25 is a rear end view. Fig. 26 is a side view showing the split. Fig. 27 is a longitudinal section at Y - Y of Fig. 24. Fig. 28 shows the bush opened at the split to admit the cable. Fig. 29 shows how the bush is compressed to enter the primary aperture during assembly. Figs 30 and 31 are respectively, front and rear views of the LRE showing the bushes and cables assembled in the primary apertures. Detailed Description

[0018] In embodiments, the latch mechanism may be used to selectively restrain and release a movable door in a wheeled or tracked vehicle. The latch mechanism is operable to retain the door in at least one retained position, optionally in more than one retained position.

[0019] The latch mechanism may be arranged on a fixed part, such as a vehicle body, to engage a staple or other cooperating part of the door; alternatively, the latch mechanism may be arranged on the door to engage one or more staples or other cooperating parts on the vehicle body or fixed part.

[0020] By way of example, Figs. 1, 5 and 6 show a work vehicle 500 including a cab 501 with a cab door 1 that is movable on hinges between a closed position (Fig. 5) and an open position (Fig. 6). A slam type door latch mechanism 30 in accordance with an embodiment is mounted on the door 1 to engage staples 2 located in spaced positions on the vehicle body to selectively retain the door 1 in each of the closed and open positions.

[0021] First and second user controls 101, 102 are spaced apart in different locations so that the door can be released from different locations of the vehicle. By way of example, the first user control 101 is located below the second user control 102, to be operable by a user standing at ground level outside the vehicle 500. The first user control 101 may be located on the vehicle body as shown. The second user control 102 may be located on the vehicle body or, as illustrated, on the door 1, and may be operable by the user when standing on the vehicle, e.g. on the access ladder. The first and second user controls 101, 102 can be operated to release the door from the retained position, which is to say, when it is retained by the latch mechanism in either of the closed and open positions.

[0022] The apparatus may include two, three, four, or more user controls and flexible cables, as required.

[0023] The illustrated embodiment includes third and fourth user controls 103, 104, each spaced apart from the others, which are arranged respectively on the vehicle body inside the cab, and on the internal side of the door 1, and are operable from inside the cab or (when the door is open) from outside the cab, to release the door from either the closed or open position.

[0024] Each of the four user controls is connected to the proximal end 21 of a respective flexible cable 201, 202, 203, 204.

[0025] Each respective flexible cable 201, 202, 203, 204 may have a respective casing 25, the flexible cable being slidable axially in the casing 25. The casing may also be flexible, and the assembly may be configured as a Bowden cable with fittings or adjusters as well known in the art. The flexible cable may be a stranded cable or a solid wire, as known in the art. The cable assemblies are routed in any convenient way between the user controls and the latch mechanism, and may run through the hinge side of the door between the door and the vehicle body as shown, or entirely through the vehicle body or inside the door.

[0026] Fig. 2 shows how each of the first, second, third and fourth user controls 101, 102, 103, 104 is connected to the proximal end 21 of the respective first, second, third or fourth flexible cable 201, 202, 203, 204.

[0027] Figs. 3 and 4 show how the first user control 101 is movable by a user to apply a tension force F to the first flexible cable 201, causing the flexible cable to slide axially through its casing 25. Each of the other user controls 102, 103, 104 is movable in the same way to apply a tension force F to its respective flexible cable 202, 203, 204.

[0028] Referring to Fig. 7, the door latch mechanism 30 includes a support element 31, which in the illustrated embodiment is configured as a casing fixed to the door 1, and a latch release element 40 movably connected to the support element 31.

[0029] The LRE (latch release element) 40 is a single rigid assembly or body, and in the illustrated embodiment includes a primary component 41 configured as a lever that pivots about a pivot axis X41 on the support element 31. The LRE 40 may be biased towards the idle position Pl (Fig. 7) by a resilient bias element or latch release spring 45, as shown.

[0030] In the illustrated embodiment, the door latch mechanism 30 further includes a striker 32 biased by a striker spring 33 to an open position (Fig. 7) in which the door is released from the retained position, so that the staple 2 can be removed from the latch mechanism. This arrangement is shown purely by way of illustration; many alternative arrangements are possible.

[0031] Fig. 8 shows how the staple 2 enters the mechanism, rotating the striker 32 which captures the staple 2 as it rotates towards its closed position (Fig. 9), also rotating the LRE 40 away from the idle position Pl and past the latched or rest position P2.

[0032] As the striker 32 reaches its closed position, the latch release spring 45 moves the LRE 40 back to the latched or rest position P2 in which it engages an abutment surface 34 of the striker 32, latching the striker 32 in its closed position and so retaining the staple 2 with the door in the retained position (Fig. 9). The door is either open or closed, depending on which staple 2 is retained.

[0033] Fig. 10 shows how the latch release element 40 is movable by the first user control 101, relative to the support element 31, in a release direction Dr, from the rest or latched position P2 to a release position P3, to operate the door latch mechanism 30 to release the door 1 from the retained position.

[0034] Figs. 13, 14, and 15 show how each of the second, third, and fourth user controls 102, 103, 104 can be operated in the same way to move the latch release element 40, via their respective flexible cables 202, 203, 204, to the release position P3.

[0035] Once the LRE 40 reaches the release position P3, the striker spring 33 rotates the striker 32 to the open position so that the staple 2 can be removed from the mechanism, releasing the door 1 (Fig. 11).

[0036] When the user releases the user control, the latch release spring 45 returns the LRE 40 to the idle position Pl (Fig. 12).

[0037] Referring again to Figs. 2-4, each of the user controls 101, 102, 103, 104 may be provided with at least one respective first resilient bias element or user control spring 15, which applies a first restoring force to bias the respective user control to a rest position.

[0038] As described above and shown in Fig. 7, the door latch mechanism 30 may include at least one second resilient bias element or latch release spring 45, which applies a second restoring force to bias the LRE 40 to the rest or latched position P2 or, as shown, through that position to the idle position P1.

[0039] The user control is movable to apply the tension force F in opposition to the first restoring force, and the latch release element 40 is movable in the release direction Dr in opposition to the second restoring force.

[0040] As illustrated, each flexible cable may be connected to its respective user control so that lost motion (discussed below) is provided also between the user control and the proximal end 21 of the flexible cable, whereby the cable is movable in one direction only by the tension force F applied by the user, and in the other direction only by the second restoring force applied by the latch release spring 45.

[0041] This ensures that the user control does not apply any axial compressive force to its respective flexible cable, and so obviates kinking of the cable.

[0042] In the illustrated embodiment, this is accomplished by connecting the proximal end 21 of the cable to the user control using a terminal body, so that the cable is slidable through an aperture of the user control, in the same way that the distal end 22 is connected to the LRE 40 (also discussed below). Lost motion

[0043] Each of the flexible cables 201, 202, 203, 204 extends from its proximal end 21 to a distal end 22, and is connected at its distal end 22 to the latch release element 40 to apply the tension force F to the latch release element 40, to move the latch release element 40, by the tension force F, in the release direction Dr from the rest or latched position P2 to the release position P3, as shown in Figs. 10, 13, 14, and 15, respectively.

[0044] Referring to Fig. 16, lost motion LI, L2 is provided between the distal end 22 of each of the flexible cables 201, 202, 203, 204, and the latch release element 40.

[0045] By this lost motion is meant motion of the LRE 40, relative to the respective flexible cable 201, 202, 203, 204.

[0046] As illustrated, the lost motion may include a first range of lost motion LI defined by movement of the LRE 40 from the idle position Pl to the rest or latched position P2, and a second range of lost motion L2 defined by movement of the LRE 40 from the rest or latched position P2 to the release position P3.

[0047] By virtue of the lost motion LI, L2, or (strictly speaking) by virtue of the second range of lost motion L2, the LRE 40 is movable in the release direction Dr by any one of the flexible cables 201, 202, 203, 204, without moving any of the other flexible cables in the release direction.

[0048] That is to say: each of the flexible cables 201, 202, 203, 204 is operable, individually, to apply the tension force F to the latch release element 40 to move the latch release element 40, by the tension force F, in the release direction Dr from the rest position P2 to the release position P3, without movement of the distal end 22 of the or each of the other flexible cables 201, 202, 203, 204 in the release direction Dr.

[0049] This makes it possible to release the latch mechanism 30 by any one of the user controls without applying force to any of the other flexible cables, and so provides a simple mechanism in which the force F that must be applied by the user to operate the mechanism is not dependent upon the number of user controls provided.

[0050] Thus, it will be understood that the first flexible cable 201 is operable to apply the tension force F to the LRE 40 to move the LRE 40, by the tension force F, in the release direction Dr from the rest position P2 to the release position P3, without movement of the distal end 22 of the second flexible cable 202 in the release direction Dr; and the second flexible cable 202 is operable to apply the tension force F to the LRE 40 to move the LRE 40, by the tension force F, in the release direction Dr from the rest position P2 to the release position P3, without movement of the distal end 22 of the first flexible cable 201 in the release direction Dr.

[0051] If a third user control 103 and flexible cable 203 are provided, then the third flexible cable 203 is operable to apply the tension force F to the LRE 40 to move the LRE 40, by the tension force F, in the release direction Dr from the rest position P2 to the release position P3, without movement of the distal ends 22 of the first and second flexible cables 201, 202 in the release direction Dr; and the first and second flexible cables 201, 202 are operable to apply the tension force F to the LRE 40 to move the LRE 40, by the tension force F, in the release direction Dr from the rest position P2 to the release position P3, without movement of the distal end 22 of the third flexible cable 203 in the release direction Dr.

[0052] If a fourth user control 103 and flexible cable 203 are provided, then the fourth flexible cable 204 is operable to apply the tension force F to the LRE 40 to move the LRE 40, by the tension force F, in the release direction Dr from the rest position P2 to the release position P3, without movement of the distal ends 22 of the first, second and third flexible cables 201, 202, 203 in the release direction Dr; and the first, second and third flexible cables 201, 202, 203 are operable to apply the tension force F to the LRE 40 to move the LRE 40, by the tension force F, in the release direction Dr from the rest position P2 to the release position P3, without movement of the distal end 22 of the fourth flexible cable 204 in the release direction Dr.

[0053] As best seen in Fig. 16, the casing 25 of each flexible cable may include a principal portion 26 with first and second ends 26', 26", and a terminal sleeve 27 with first and second ends 27', 27".

[0054] The terminal sleeve 27 helps to keep dust out of the cable assembly. A similar terminal sleeve can be provided at the user control, as shown.

[0055] Each flexible cable 201, 202, 203, 204 extends slidably through the principal portion 26 and the terminal sleeve 27, except that the terminal sleeve 27 is fixed (e.g. clamped) proximate its second end IT' to the respective flexible cable 201, 202, 203, 204, so that its second end 27" will move together with the flexible cable while the flexible cable slides through the rest of the terminal sleeve.

[0056] The principal portion 26 of the casing 25 extends between the terminal sleeve 27 and the proximal end 21 of the flexible cable for most of the length of the flexible cable, and may be fixed at its second end 26" in fixed relation to a bracket 16 or other fixed part of the respective user control (Figs. 2 - 4) so that a moving part 17 of the user control, when operated, will move the flexible cable slidingly through the casing 25.

[0057] The principal portion 26 and the terminal sleeve 27 are connected together (directly or indirectly, e.g. via a fixed bracket 35 as shown), in series relation at their respective first ends 26', 27'.

[0058] The principal portion 26 is fixed proximate its first end 26' in fixed relation to the support element 31, e.g. to the bracket 35 which is fixed relative to the support element 31.

[0059] As illustrated in Fig. 16 (showing the terminal sleeve at rest in broken lines, and retracted in solid lines), and as shown in Fig. 10 and Figs. 13 - 15, each terminal sleeve 27 is flexibly and axially contractable, by the tension force F, towards its first end 27', as its second end 27" moves together with its respective flexible cable.

[0060] The distal end portion 23 of each flexible cable is arranged outside the respective terminal sleeve 27 and extends from the second end 27" of the terminal sleeve to the respective terminal body 24. The distal end portion 23 has a length L23 (Fig. 16) at least equal to an axial extent of the lost motion LI, L2 to accommodate the lost motion LI, L2 between the second end 27" of the terminal sleeve 27 and the respective terminal body 24. The LRE (latch release element)

[0061] Referring now to Figs. 16, 18, 30 and 31, the LRE 40 may include a plurality of cable apertures 51, each extending through the LRE 40 along a central axis X51 of the respective cable aperture 51, with each cable aperture 51 being bounded by a respective bounding surface 52 of the latch release element 40.

[0062] Each of the flexible cables 201, 202, 203, 204 has a distal end portion 23 terminating at a respective terminal body 24, the terminal body 24 being fixed at the distal end 22 of the respective flexible cable 201, 202, 203, 204.

[0063] As shown in Figs. 21 - 23, the terminal body may be a cylindrical metal block that is swaged to the end of the cable, as well known in the art; other arrangements are possible.

[0064] Each respective distal end portion 23 extends slidably through a respective one of the cable apertures 51, and is confined within the cable aperture 51 by the bounding surface 52.

[0065] Each terminal body 24 is arranged to abut the latch release element 40, when the tension force F is applied to the respective flexible cable, to transfer the tension force F to the latch release element 40.

[0066] As illustrated, the latch release element 40 may be pivotable about a pivot axis X40 between the rest position P2 and the release position P3.

[0067] Fig. 17 illustrates the LRE 40 partially sectioned in a plane PX51 perpendicular to the pivot axis X40 and containing the central axis X51 of a respective one of the cable apertures 51. Although the distal end portion 23 of each of the flexible cables may be free to move about within the bounding surface 52 of its respective cable aperture 51, in the position as illustrated in Fig. 17, the distal end portion 23 of the respective flexible cable 201 is straight and extends along a central axis X23 of the distal end portion 23 that is contained in the plane PX51.

[0068] When considered in the plane PX51, the bounding surface 52 of the respective cable aperture 51 defines two sets of points 71, 72 spaced apart by the cable aperture 51. Pivotal movement of the LRE 40 about the pivot axis X40, from the rest or latched position P2 to the release position P3, causes the two sets of points 71, 72 to move about the pivot axis X40 to describe two respective sets of imaginary arcs 73, 74 in the plane PX51. The two sets of imaginary arcs 73, 74 are spaced apart by a gap 75 on opposite sides of the distal end portion 23 of the respective flexible cable 201.

[0069] As illustrated, the gap 75 may be sufficient to accommodate the respective distal end portion 23 between the two sets of imaginary arcs 73, 74 without contacting either of the two sets of imaginary arcs 73, 74, when (as shown) the distal end portion 23 is straight and extends along the central axis X23 of the distal end portion 23 that is contained in the plane PX51.

[0070] This means that the pivotable LRE 40 can be rotated to the release position P3 by actuating a respective one of the flexible cables without deflecting the other ones of the cables.

[0071] Referring also to Figs. 19 and 20, the LRE 40 may be arranged to allow easy insertion of the flexible cables into the cable apertures.

[0072] For this purpose, as illustrated, the primary component 41 of the LRE 40 may have a plurality of primary apertures 42 (one for each cable), each primary aperture 42 extending through the primary component 41 along the central axis X51 of a respective one of the cable apertures 51, wherein each primary aperture 42 communicates with a respective insertion slot 43 extending away from the central axis X51 of the respective cable aperture 51 through an outer surface 44 of the primary component 41.

[0073] Once assembled as shown in Figs. 30 and 31, each respective distal end portion 23 extends slidably through a respective one of the primary apertures 42. During assembly, the respective flexible cable may be introduced into the primary aperture 42 via the insertion slot 43 without passing either respective end 21, 22 of the flexible cable through the primary aperture 42.

[0074] As illustrated, each respective primary aperture 42 may be lined with a respective bush 50 which defines the respective cable aperture 51, so that the bounding surface 52 of the respective cable aperture 51 is an internal surface of the bush 50. The bush 50 is retained in the primary aperture 42 to prevent the respective flexible cable from escaping the primary aperture 42 via the insertion slot 43.

[0075] Referring also to Figs. 24 - 28, each bush 50 may be split so that, before assembling the bush 50 into the primary aperture 42, the respective flexible cable may enter the cable aperture 51 of the bush 50 without passing either respective end 21, 22 of the cable through the cable aperture 51.

[0076] As illustrated, each bush 50 may include a retaining structure 56 (such as one or more radially outwardly extending wings, optionally having ramped surfaces as shown), a tubular body 54 surrounding the cable aperture 51, and a flange 55 that extends radially outwardly from the tubular body 54 at an axial end of the tubular body 54.

[0077] The tubular body 54 and the flange 55 are split to define at least one insertion opening 53 for admitting the respective flexible cable into the cable aperture 51 during assembly.

[0078] The bush 50 may be moulded in one piece from plastics material so as to be flexibly deformable with a single split at one point on its circumference, so that it can opened up at the split as shown in Fig. 28 to define at least one insertion opening 53 that receives the distal end portion 23 of the cable, which already has the terminal body 24 swaged to its distal end 22. The distal end portion 23 can then be passed through the insertion slot 43 before pressing the bush 50 into the primary aperture 42.

[0079] Once the bush 50 is inserted in the primary aperture 42, the tubular body 54 is confined in the primary aperture 42 in a closed condition of the bush 50. In the closed condition the insertion opening 53 is substantially closed, so that the bounding surface 52 blocks the insertion slot 43 of the primary component 41.

[0080] The retaining structure 56 may be configured to engage the primary component 41 to retain the bush 50 in snap-fit relation in the respective primary aperture 42 - which is to say, when the bush 50 is pressed into the primary aperture 42, its resilient structure causes it to snap into place, retaining it in the primary aperture 42 in its assembled position.

[0081] As shown in Fig. 29, the bush 50 may be elastically deformable, in the closed condition of the bush 50, to a compressed condition in which the retaining structure 56 can pass through the primary aperture 42 during assembly. The bush 50 is configured to resile from the compressed condition when the flange 55 and the retaining structure 56 are arranged on opposite sides of the primary component 41, so that the tubular body 54 is retained in the closed condition, in the primary aperture 42, between the flange 55 and the retaining structure 56, as shown for example in Figs. 16, 30 and 31.

[0082] After assembly, as illustrated, the flange 55 may be arranged between the terminal body 24 of the respective flexible cable 201, 202, 203, 204 and the primary component 41.

[0083] For clarity, Fig. 18 shows the bushes 50 in the assembled position but with the flexible cables removed.

[0084] By using a bush to close the insertion slot 43 in the primary component 41, it is ensured that the distal end portion 23 of the cable will remain captive in the cable aperture 51 even when in a slack condition. Industrial Applicability

[0085] In comparison with some prior art arrangements, the novel mechanism is mechanically simple and inexpensive, and is particularly useful in applications where scale or complex geometry makes it impractical to transfer motion using pushrods.

[0086] Advantageously, the lost motion between the LRE and the distal end of each flexible cable makes it possible to arrange as many cables as desired in functionally parallel relation, so that each cable can apply a tension force to the LRE to operate the latch mechanism independently of the others. This provides a simple and adaptable assembly in which the latch mechanism can be operated from as many different user controls spaced apart in as many different positions as may be required, for example, to suit the requirements of a large and complex work machine.

[0087] In tests, the apparatus is found to be robust and resistant to clogging when operated in dusty conditions.

[0088] Assembly is particularly easy by means of a snap-fit bush which is split to allow insertion of the distal end portion of the cable. This allows the cable to be assembled together with the terminal body (which may be swaged onto the distal end of the cable), before passing the distal end portion via the insertion slot into the primary aperture, and via the insertion opening of the bush into the cable aperture. The bush is then pushed axially into the primary aperture, compressing the tubular body and retaining structure, until the retaining structure snaps (resiles) into position behind the rear surface of the primary component at the primary aperture. This provides a simple and reliable assembly.

[0089] The snap-fit bush may be a unitary plastics moulding with a split defining a single insertion opening, or may be made in two or more parts defining one or more insertion openings through or between the respective parts.

[0090] In alternative embodiments, the bush could be made from plastics or metal and retained in the primary aperture by plastic deformation (e.g. swaging) or by screwing together respective parts of the bush. The cable could be threaded through the bush before fixing the terminal body to the distal end of the cable.

[0091] Alternatively, the cable aperture could be formed as a hole through the primary component of the LRE, with a closed (continuous) boundary defining the bounding surface, and the cable could be threaded through the cable aperture before fixing the terminal body to the distal end of the cable.

[0092] In yet further embodiments, the cable could be introduced via an insertion slot into a primary aperture of a primary component of the LRE (e.g. as illustrated) before closing the insertion slot with a secondary component of the LRE. Instead of forming the secondary component as a bush as illustrated, it could be configured as a closure element such as, for example, a screw or a plate. In such arrangements, most of the bounding surface of the cable aperture may be a bounding surface of the primary aperture, and the remainder a surface of the closure element.

[0093] In yet further embodiments, the cable aperture could be formed as a hole through a secondary component of the LRE, for example, a plate, which is fixed to a primary component of the LRE, through which the primary aperture is formed. The cable could be threaded through the hole before fixing the terminal body to the distal end of the cable. Alternatively, the hole through the secondary component of the LRE could communicate with a slot in the secondary component of the LRE, through which the cable can be inserted into the hole without passing either end of the cable through the hole. The secondary component could then be fixed to the primary component of the LRE in a position selected so that (if provided) the slot in the secondary component is closed by a solid part of the primary component, and (if provided) the insertion slot of the primary aperture, formed in the primary component, is closed by a solid part of the secondary component.

[0094] Thus, the bounding surface of the cable aperture may be defined by respective surfaces of respective, primary and secondary components of the LRE.

[0095] For example, if the secondary component is a flat plate, then the plate could be fixed against a flat surface of the primary component of the LRE (which could be a lever body, similar to that of the illustrated embodiment) so that the respective slots are misaligned.

[0096] In yet further embodiments, the LRE may include a primary component defining (for each respective cable) a primary aperture with an insertion slot, and a secondary component (or components) also having insertion slots to admit the cable, and configured to close the insertion slots in the primary component when inserted into the primary apertures, wherein the primary and secondary components are configured to define a rotational position of the or each secondary component in the respective primary aperture to angularly misalign the respective insertion slots in the primary and secondary components about the axis of the cable aperture.

[0097] In summary, in embodiments, a door latch mechanism includes a latch release element (LRE) that is operable to release the door via flexible cables extending from at least two user controls. Lost motion is provided between the distal end of each flexible cable and the LRE, so that each user control can operate the LRE independently of the others without transferring the movement to the other flexible cables.

[0098] The mechanism may be mounted on a door or on a fixed structure proximate the door, for selectively latching and unlatching the door on a vehicle or any other structure.

[0099] Purely for ease of understanding, the illustrated example shows a slam type latch release mechanism mounted on a door and including a striker for engaging staples on a vehicle body. However, the novel mechanism can be implemented in other configurations for use in any application within the scope of the claims.

[00100] The LRE can have any desired configuration, and the distal end portions of the cables may be connected to the LRE in any desired arrangement within the scope of the claims.

[00101] For ease of illustration, the LRE is illustrated as a pivotable lever, with the flexible cables connected to the lever at different distances from the pivot so that they have different lengths of travel and so, different ranges of lost motion, with each user control being operable to move the respective cable through a corresponding length of travel.

[00102] However, in other embodiments, the LRE may be mounted for movement in any desired manner, for example, in translation or in rotation about one or more axes, and the flexible cables may be positioned to have either equal or different distances of travel.

[00103] The user controls need not be configured as shown, and may be of similar or different design; for example, one user control may be configured as a lever, and another as a handle or button.

[00104] The flexible cables may be spring biased to a rest position independently of the LRE and the user controls.

[00105] Each of the flexible cables may include a principal portion (extending for most of its length) and a distal end portion attached end-to-end in series relation to the principal portion; in this way, for example, the distal end portion might be arranged as a relatively less flexible rod, with the principal portion being a stranded cable or a wire.

[00106] Many further adaptations are possible within the scope of the claims.

[00107] In the claims, reference numerals and characters are provided in parentheses, purely for ease of reference, and should not be construed as limiting features. LIST OF ELEMENTS TITLE: Door latch mechanism operable via cables from multiple user controls FILE: 24-0421GB01 1 Door 2 Staple 15 First resilient bias element 16 Bracket 17 Moving part 21 Proximal end of flexible cable 22 Distal end of flexible cable 23 Distal end portion of flexible cable 24 Terminal body 25 Casing 26 Principal portion of casing 26' First end of principal portion 26" Second end of principal portion 27 Terminal sleeve 27' First end of terminal sleeve 27" Second end of terminal sleeve 30 Door latch mechanism 31 Support element 32 Striker 33 Striker spring 34 Striker abutment surface 35 Bracket 40 Latch release element (LRE) 41 Primary component Primary aperture Insertion slot Outer surface of latch release element Second resilient bias element Bush Cable aperture Bounding surface of cable aperture Insertion opening Tubular body Flange Retaining structure Point Point Set of imaginary arcs Set of imaginary arcs Gap between sets of imaginary arcs First user control Second user control Third user control Fourth user control First flexible cable Second flexible cable Third flexible cable Fourth flexible cable Vehicle Cab Release direction Tension force Lost motion (Pl - P2) Lost motion (P2 - P3) L23 Length of distal end portion Pl Idle position P2 Rest position (latched position) P3 Release position (unlatched position) PX51 Plane X23 Central axis of distal end portion X40 Pivot axis of latch release element X51 Central axis of cable aperture

Claims

What is claimed is:

1. An apparatus including:amovable door (1);a door latch mechanism (30) for selectively retaining the door (1) in at least one retained position;first and second user controls (101, 102), the user controls being spaced apart in different locations; andfirst and second flexible cables (201, 202), each flexible cable having a proximal end (21) and a distal end (22);the door latch mechanism (30) including a support element (31) and a latch release element (40) movably connected to the support element (31), the latch release element (40) being a single rigid assembly or body;the latch release element (40) being movable relative to the support element (31), in a release direction (Dr), from a rest position (P2) to a release position (P3), to operate the door latch mechanism (30) to release the door (1) from the retained position;the first user control (101) being connected to the proximal end (21) of the first flexible cable (201) and movable by a user to apply a tension force (F) to the first flexible cable (201);the second user control (102) being connected to the proximal end (21) of the second flexible cable (202) and movable by a user to apply a tension force (F) to the second flexible cable (202);wherein:each of the first and second flexible cables (201, 202) is connected at its distal end (22) to the latch release element (40) to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by saidtension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3); andlost motion (LI, L2) is provided between the distal end (22) of each of the first and second flexible cables (201, 202) and the latch release element (40), so that:the first flexible cable (201) is operable to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3), without movement of the distal end (22) of the second flexible cable (202) in the release direction (Dr); andthe second flexible cable (202) is operable to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3), without movement of the distal end (22) of the first flexible cable (201) in the release direction (Dr).

2. An apparatus according to claim 1, further including:a third user control (103), the third user control being spaced apart from the first and second user controls (101, 102), anda third flexible cable (203) having a proximal end (21) and a distal end (22);the third user control (103) being connected to the proximal end (21) of the third flexible cable (203) and movable by a user to apply a tension force (F) to the third flexible cable (203);the third flexible cable (203) being connected at its distal end (22) to the latch release element (40) to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3);wherein lost motion (LI, L2) is provided between the distal end (22) of the third flexible cable (203) and the latch release element (40), so that:the third flexible cable (203) is operable to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3), without movement of the distal ends (22) of the first and second flexible cables (201, 202) in the release direction (Dr); andthe first and second flexible cables (201, 202) are operable to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3), without movement of the distal end (22) of the third flexible cable (203) in the release direction (Dr).

3. An apparatus according to claim 2, further including:a fourth user control (104), the fourth user control being spaced apart from the first, second and third user controls (101, 102, 103), anda fourth flexible cable (204) having a proximal end (21) and a distal end (22);the fourth user control (104) being connected to the proximal end (21) of the fourth flexible cable (204) and movable by a user to apply a tension force (F) to the fourth flexible cable (204);the fourth flexible cable (204) being connected at its distal end (22) to the latch release element (40) to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3);wherein lost motion (LI, L2) is provided between the distal end (22) of the fourth flexible cable (204) and the latch release element (40), so that:the fourth flexible cable (204) is operable to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3), without movement of the distal ends (22) of the first, second and third flexible cables (201, 202, 203) in the release direction (Dr); andthe first, second and third flexible cables (201, 202, 203) are operable to apply said tension force (F) to the latch release element (40) to move the latch release element (40), by said tension force (F), in the release direction (Dr) from the rest position (P2) to the release position (P3), without movement of the distal end (22) of the fourth flexible cable (204) in the release direction (Dr).

4. An apparatus according to any preceding claim, wherein the latch release element (40) includes a plurality of cable apertures (51);each of the cable apertures (51) extending through the latch release element (40) along a central axis (X51) of the respective cable aperture (51), each cable aperture (51) being bounded by a respective bounding surface (52) of the latch release element (40); andeach of the flexible cables (201, 202, 203, 204) has a distal end portion (23) terminating at a respective terminal body (24), the terminal body (24) being fixed at the distal end (22) of the respective flexible cable (201, 202, 203, 204); andeach respective distal end portion (23) extends slidably through a respective one of the cable apertures (51),the distal end portion (23) being confined within the cable aperture (51) by the bounding surface (52); andeach terminal body (24) is arranged to abut the latch release element (40), when the tension force (F) is applied to the respective flexible cable (201, 202, 203, 204), to transfer the tension force (F) to the latch release element (40).

5. An apparatus according to claim 4, wherein the latch release element (40) is pivotable about a pivot axis (X40) between the rest position (P2) and the release position (P3); and,when considered in a plane (PX51) perpendicular to the pivot axis (X40) and containing the central axis (X51) of a respective one of the cable apertures(51), the bounding surface (52) of the respective cable aperture (51) defines two sets of points (71, 72) spaced apart by the cable aperture (51); andpivotal movement of the latch release element (40) about the pivot axis (X40), from the rest position (P2) to the release position (P3), causes said two sets of points (71, 72) to move about the pivot axis (X40) to describe two respective sets of imaginary arcs (73, 74) in the plane (PX51),said two sets of imaginary arcs (73, 74) being spaced apart by a gap (75) on opposite sides of the distal end portion (23) of the respective flexible cable (201,202, 203,204); andthe gap (75) is sufficient to accommodate said distal end portion (23) between said two sets of imaginary arcs (73, 74), without contacting either of said two sets of imaginary arcs (73, 74), when the distal end portion (23) is straight and extends along a central axis (X23) of the distal end portion (23) that is contained in the plane (PX51).

6. An apparatus according to claim 4 or claim 5, wherein:the latch release element (40) includes a primary component (41), the primary component (41) having a plurality of primary apertures (42), each primary aperture (42) extending through the primary component (41) along the central axis (X51) of a respective one of the cable apertures (51); andeach respective distal end portion (23) extends slidably through a respective one of the primary apertures (42); andeach primary aperture (42) communicates with a respective insertion slot (43) extending away from the central axis (X51) of the respective cable aperture (51) through an outer surface (44) of the primary component (41), whereby the respective flexible cable (201, 202, 203, 204) may be introduced into the primary aperture (42) via the insertion slot (43) without passing either respective end (21, 22) of the flexible cable (201, 202, 203, 204) through the primary aperture (42).

7. An apparatus according to claim 6, wherein each respective primary aperture (42) is lined with a respective bush (50);the bush (50) defining the respective cable aperture (51), the bounding surface (52) of the respective cable aperture (51) being an internal surface of the bush (50);the bush (50) being retained in the primary aperture (42) to prevent the respective flexible cable (201, 202, 203, 204) from escaping the primary aperture (42) via the insertion slot (43).

8. An apparatus according to claim 7, wherein the bush (50) is split so that, before assembling the bush (50) into the primary aperture (42), the respective flexible cable (201, 202, 203, 204) may enter the cable aperture (51) of the bush (50) without passing either respective end (21, 22) of the cable (201, 202, 203, 204) through the cable aperture (51).

9. An apparatus according to claim 8, wherein:the bush (50) includes:a retaining structure (56),a tubular body (54) surrounding the cable aperture (51), anda flange (55); andthe retaining structure (56) is configured to engage the primary component (41) to retain the bush (50) in snap-fit relation in the respective primary aperture (42); andthe flange (55) extends radially outwardly from the tubular body (54) at an axial end of the tubular body (54); andthe tubular body (54) and the flange (55) are split to define at least one insertion opening (53) for admitting the respective flexible cable (201, 202, 203, 204) into the cable aperture (51) during assembly; andthe tubular body (54) is confined in the primary aperture (42) in a closed condition of the bush (50), wherein in the closed condition the insertion opening (53) is substantially closed; andthe bush (50) is elastically deformable, in the closed condition of the bush (50), to a compressed condition in which the retaining structure (56) can pass through the primary aperture (42) during assembly; andthe bush (50) is configured to resile from the compressed condition when the flange (55) and the retaining structure (56) are arranged on opposite sides of the primary component (41), so that the tubular body (54) is retained in the closed condition, in the primary aperture (42), between the flange (55) and the retaining structure (56).

10. An apparatus according to claim 9, wherein the flange (55) is arranged between the terminal body (24) of the respective flexible cable (201, 202, 203, 204) and the primary component (41).

11. An apparatus according to any preceding claim, wherein:each of the user controls (101, 102, 103, 104) is provided with at least one respective first resilient bias element (15), and is biased to a rest position by a first restoring force applied by the at least one respective first resilient bias element (15), and movable to apply said tension force (F) in opposition to the first restoring force; andthe door latch mechanism (30) includes at least one second resilient bias element (45), andthe latch release element (40) is biased to the rest position by a second restoring force applied by the at least one second resilient bias element (45), and movable in the release direction (Dr) in opposition to the second restoring force.-SO-12. An apparatus according to any preceding claim, wherein each respective flexible cable (201, 202, 203, 204) has a respective casing (25), the flexible cable (201, 202, 203, 204) being slidable in the casing (25).

13. An apparatus according to claim 4 or claim 5, wherein each respective flexible cable (201, 202, 203, 204) has a respective casing (25), the flexible cable (201, 202, 203, 204) being slidable in the casing (25);the casing (25) including a principal portion (26) and a terminal sleeve (27), the respective flexible cable (201, 202, 203, 204) extending slidably through the principal portion (26) and the terminal sleeve (27);the terminal sleeve (27) having a first end (27') and a second end (27");the principal portion (26) having a first end (26') and a second end (26") and extending between the terminal sleeve (27) and the proximal end (21) of the flexible cable;the principal portion (26) and the terminal sleeve (27) being connected together in series relation at their respective first ends (26', 27');the principal portion (26) being fixed proximate its first end (26') in fixed relation to the support element (31);the terminal sleeve (27) being fixed proximate its second end (27") to the respective flexible cable (201, 202, 203, 204);the terminal sleeve (27) being flexibly and axially contractable, by the tension force (F), towards its first end (27');the distal end portion (23) of the respective flexible cable (201, 202, 203, 204) being arranged outside the terminal sleeve (27) and extending from the second end (27") of the terminal sleeve (27) to the respective terminal body (24);the distal end portion (23) having a length (L23) at least equal to an axial extent of said lost motion (LI, L2) to accommodate the lost motion (LI, L2) between the second end (27") of the terminal sleeve (27) and the respective terminal body (24).

14. A wheeled or tracked vehicle (500) including an apparatus according to any preceding claim.

15. A wheeled or tracked vehicle (500) according to claim 14, wherein the vehicle includes a cab (501), and the door (1) is a door of the cab (501), and the first user control (101) is located below the second user control (102) to be operable by a user standing at ground level outside the vehicle (500).

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