Track- or rail-mounted closure drive assembly
11505982 · 2022-11-22
Assignee
Inventors
Cpc classification
E05F15/681
FIXED CONSTRUCTIONS
E06B9/74
FIXED CONSTRUCTIONS
International classification
E05F15/681
FIXED CONSTRUCTIONS
E06B9/74
FIXED CONSTRUCTIONS
Abstract
A device for a closure drive assembly can include: a moveable trolley, the trolley configured for movement along a track or a rail under drive by a drive component to move a closure between an open position and a closed position, the trolley including a body having a guiding surface; a rotating body having one or more camming surfaces, rotation of the rotating body about a rotation axis being supported by the guiding surface; and a lever having a lever camming surface configured to engage with one or more of the camming surfaces of the rotating body, wherein the lever is associated with an engagement member such that rotation of the lever moves the lever camming surface along the one or more rotating body camming surfaces to displace the engagement member, and wherein the engagement member is arranged to provide selective engagement between the moveable trolley and the drive component.
Claims
1. A device for a track- or rail-mounted closure drive assembly, the device including: a moveable trolley associated with a closure, the trolley configured for movement along the track or rail under drive by a drive component to move the closure between an open position and a closed position, the trolley including a body having a guiding surface; a rotating body having one or more camming surfaces, rotation of the rotating body about a rotation axis being supported by the guiding surface; and a lever having a lever camming surface configured to engage with one or more of the camming surfaces of the rotating body, wherein the lever is associated with an engagement member such that rotation of the lever moves the lever camming surface along the one or more rotating body camming surfaces to displace the engagement member, and wherein the engagement member is arranged to provide selective engagement between the moveable trolley and the drive component.
2. The device of claim 1, wherein: the lever is arranged to rotate about said rotation axis by application of a specific user action; the engagement member is arranged to move between two alternative positions to afford, respectively, engagement and disengagement between the moveable trolley and the drive component; and wherein successive applications of said specific user action results in the rotating body moving the engagement member between the two alternative positions.
3. The device of claim 2, wherein the one or more camming surfaces include one or more engagement setting surfaces whose engagement with the lever camming surface serves to place or hold the engagement member in the engaged position.
4. The device of claim 3, wherein the one or more camming surfaces include one or more disengagement setting surfaces whose engagement with the lever camming surface serves to place or hold the engagement member in the disengaged position.
5. The device of claim 3, further including a visual indicator associated with the one or more engagement setting surfaces and/or one or more disengagement setting surfaces to provide a visual indication of whether the engagement member is engaged or disengaged with the drive component.
6. The device of claim 2, wherein said specific user action on the lever is a motion completed in a direction with a complement of movement substantially away from the closure.
7. The device of claim 1, wherein movement of the engagement member is along the rotation axis of the rotating body.
8. The device of claim 1, further including a spring to bias the lever and the rotating body towards a support body together in an axial direction.
9. The device of claim 8, wherein the spring is a first spring, the device further including a second spring, configured such that when the lever is rotated the lever is biased by the second spring back to a rest position, wherein the and the second spring are provided by a single coil spring.
10. The device of claim 1, further including a spring, configured such that when the lever is rotated the lever is biased by the spring back to a rest position.
11. The device of claim 1, further including a latch for latching the trolley to the track or rail, the latch moveable between a latched position and an unlatched position, the latch actuated by rotation of the rotating body.
12. The device of claim 11, wherein said latch comprises a latch lever mounted for pivoting movement around a latch lever axis on said trolley.
13. The device of claim 12, wherein the latch lever includes a hook portion to engage, when the latch is in the latched position, with a latch stop on or mounted to the track or rail.
14. The device of claim 11, wherein a circumferential surface of the rotating body provides a cam surface, and a part of the latch provides a complementary follower, such that rotation of the rotating body drives the latch between said latched and unlatched positions.
15. The device of claim 11, wherein said latch is arranged to automatically move into the unlatched position when said drive component is operated to move the trolley along the track or rail.
16. The device of claim 15, wherein the drive component includes an element which, when the drive component is operated and the latch is in the latched position, interacts with a part of the latch to move the latch into the unlatched position, irrespective of any movement of the rotating body.
17. The device of claim 11, wherein the engagement between the engagement member and the drive component includes a lost motion arrangement, to allow limited movement of the drive component relative to the trolley, resulting in movement of the latch into the unlatched position, before further movement of the drive component causes movement of the trolley along the track or rail.
18. A closure drive assembly including: a drive motor unit; a drive arrangement actuated by the motor unit, including said drive component; and the device of claim 1.
19. A closure assembly, including: a closure mounted to move between the open position and the closed position; and the closure drive assembly of claim 18.
20. A device for a track- or rail-mounted closure drive assembly, the device including: a moveable trolley associated with a closure, the trolley configured for movement along the track or rail under drive by a drive component to move the closure between an open position and a closed position; an engagement member arranged to provide selective engagement between the trolley and the drive component; a support body on the trolley having a throughbore for movement of the engagement member, the throughbore having an axis, the body further having an indexed ratchet guiding surface arranged around the throughbore and comprising an angularly spaced succession of ramp and stop portions; a rotating body arranged for rotation about said axis and having a throughbore for movement of the engagement member, the body having on one side an engagement surface comprising an angularly spaced succession of ramp and stop portions complementary to the indexed ratchet guiding surface of the support body, and having on the other side a camming surface comprising an angularly spaced succession of ramp and stop portions; and a lever arranged for rotation about said axis, the lever having a lever camming surface comprising an angularly spaced succession of ramp and stop portions configured for cooperation with the camming surface of the rotating body, wherein the camming surface and lever camming surface are configured such that rotation of the lever from a rest position through a prescribed angle moves the lever camming surface into a position where one or more stop portions of the lever camming surface engage with one or more stop portions of the rotating body camming surface, and rotation of the lever back to the rest position rotates the rotating body with respect to the support body such that one or more stop portions of the rotating body engagement surface move to engage the next successive stop portion(s) of the indexed ratchet guiding surface, wherein one of the rotating body camming surface and the lever camming surface include one or more offset surfaces, configured such that each successive rotation of the lever through said prescribed angle and back to the rest position results in an adjustment of a separation of the lever and the support body in an axial direction, and wherein the engagement member is associated with the lever such that the position of the engagement member is determined by the separation of the lever and the support body in the axial direction.
21. A device for a closure drive assembly comprising a lever and cam arrangement to drive an engagement member between an engaged position and a disengaged position, the engaged position allowing motor drive of a closure and the disengaged position disconnecting the drive from the motor to the closure, the device configured for installation in a position relative to a closure operated by said closure drive assembly, the device comprising a user actuator attached to the lever, the device configured such that pulling of the user actuator in a generally downward direction drives the engagement member between the engaged and disengaged positions, wherein the user actuator is arranged such that successive pulling of the user actuator in a generally downward direction from a start position over a prescribed distance and release of the user actuator to return under a resilient force substantially to said start position results in the engagement member alternating between said engaged position and said disengaged position, and the closure drive assembly is configured such that the alternation between said engaged position and said disengaged position can only be realized if the force on the user actuator in the generally downward direction includes a component of force substantially in a direction away from the closure.
22. The device of claim 21, wherein the closure is a door.
23. The device of claim 22, wherein the force on the user actuator acts along a direction angled at least 10 degrees away from vertical in a direction away from the closure.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) By way of example only, preferred embodiments of the invention will be described more fully with reference to the accompanying figures, wherein:
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DETAILED DESCRIPTION OF THE DRAWINGS
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First Embodiment
(17) Trolley 10 is shown in
(18)
(19) The inclined guiding surfaces 114 are angled relative to the lower guiding surfaces 112 and the upper guiding surfaces 116, and form a smooth transition therebetween. The transverse guiding surfaces 118 respectively extend, in a substantially perpendicular manner, between the upper guiding surfaces 116 and the adjacent lower guiding surfaces 112, and thus form an abrupt step therebetween. As evident in
(20) Trolley body 100 further includes a lateral shuttle receiving portion 130 as shown, which includes a rectangular profile shuttle bore 132, sized and configured to receive drive belt 8 and a shuttle 600 therethrough. Trolley body 100 also includes a closure arm bracket 140 for attachment to closure arm 4, allowing movement of trolley 10 to be transferred to door 2. In addition, trolley body 100 includes an elongated lever aperture 150 to allow movement of lever 300 therethrough. A stop 160 provided on trolley body 100 is positioned above a part of the lever 300 to provide a resting position for lever 300 and to prevent its over-rotation.
(21) Rotating body 200 is further shown in
(22) A front face of rotating body 200 (
(23) Camming surfaces 202 include various arcuately extending parts, with radial transitions therebetween, comprising lower surfaces 212a, 212b and upper surfaces 216a, 216b, with inclined ramp surfaces 214a, 214b providing a smooth transition therebetween. Upper surfaces 216a, 216b terminate in first transverse surfaces 222a, 222b (orientated parallel to central axis 201), which provide a step down to intermediate lower surfaces 220a, 220b which act as offset setting surfaces (as described below), which in turn step down to lower surfaces 212a, 212b by way of second transverse surfaces 218a, 218b. It will be appreciated that surfaces 212a, 214a, 216a, 220a and 222a are respectively positioned on diametrically opposite sides of rotating body 200 to surfaces 212b, 214b, 216b, 220b and 222b. The lower, upper and intermediate lower surfaces 212, 216 and 220 are all planar surfaces extending perpendicularly to central axis 201.
(24) The intermediate lower surfaces 220a, 220b provide offset setting surfaces. As described in further detail below, these surfaces 220 assist in disengaging an engagement member 430 by providing an offset position therefor.
(25) A rear face of rotating body 200 (
(26) Each subset of body camming surfaces (e.g. surfaces 232a, 234a, 236a, 238a) extends through a quarter of the full arcuate range. As will be understood from the description below, the movement of the body camming surfaces 230 against the guiding surfaces 110 provides indexing of the rotational movement of rotating body 200 around annular support boss 120.
(27) Lever 300 is illustrated in
(28) Lever camming surfaces 310 comprise inclined lever surfaces 314a, 314b which meet upper lever surfaces 316a, 316b. Upper lever surfaces 316a, 316b terminate in transverse lever surfaces 318a, 318b (orientated parallel to central axis 201), which provide a step transition down to a lower lever surface 312. Lower lever surface 312 and upper lever surfaces 316a and 316b are planar surfaces extending perpendicularly to central axis 201. As
(29) On the arm of lever 300, near the lever camming surfaces, is a notch 326 shaped to receive the end of spring 410, as discussed below.
(30) At the other end of the lever arm of lever 300 a lever end portion 330 is provided, having a release member attachment 332, to be connected to the release member 500 (e.g. a cord) to afford actuation of lever 300. It will be appreciated that lever 300 and release member 500 may be integrated or alternatively made from separate parts. In addition, lever 300 includes an end stop portion 334 configured to engage with stop 160 of trolley body 100.
(31) As discussed further below, engagement member 430 is a cylindrical pin arranged to be driven in the axial direction by movement in that direction by the lever 300, against the force of a coil spring 410, by virtue of retaining clip 440 carried in a circumferential groove in member 430. When engagement assembly 400 is assembled, spring 410 is positioned in a compressed state between lever 300 (with a suitably shaped end of the spring locating in notch 326) and an end plate 420, which acts to bias lever 300 towards its resting position. Spring 410 serves to bias engagement member 430 into the shuttle bore 132 to engage with shuttle 600 by way of a groove or suitable recess in the outer wall thereof. As will be understood, when member 430 is engaged with shuttle 600, movement of drive belt 8 results in trolley 10 travelling along track 9.
(32) In the resting position, end stop portion 334 of lever 300 engages with stop 160. The ends of spring 410 are engaged with end plate 420 and lever 300, so to bias lever 300 towards this resting position. Spring 410 thus acts both as a compression spring and as a torsion spring.
(33) As
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(35) Further, in this configuration, guiding surfaces 110 are engaged with corresponding body camming surfaces 230. Lower guiding surface 112b is engaged with upper body surface 236d, upper guiding surface 116a is engaged with lower body surface 232a, and inclined guiding surface 114a is engaged with the inclined body surface 234a. There is similar engagement between the other respective elements of these camming surfaces.
(36) In this configuration, and as can be seen in
(37) If the user wishes to disengage the trolley from the drive, eg. to manually operate door 2, engagement member 430 needs to be withdrawn from engagement with shuttle 600. To this end, the user pulls down on release member 500, which rotates lever 300 to the position illustrated in
(38) Further, as lever 300 is rotated in this way, the torque on spring 410 increases.
(39) At a certain point of rotation of lever 300, upper lever surfaces 316 move beyond the end of upper surfaces 216 and under force of spring 410 move relative to rotating body 200 to abut offset setting surfaces 220, accompanied by a click audible to the user. The configuration of the mechanism is such that this point can only be reached by operating release member 500 with a substantial component of movement in a direction away from door 2. This substantial component may be, for example, 10° away from vertical in a direction away from the door.
(40) At this point, release of member 500 by the user allows lever 300 to rotate back under spring force to its resting position, at which stop portion 334 engages once again with stop 160. During this rotation, transverse lever surfaces 318 engage first transverse lever surfaces 222, so to rotate rotating body 200 through 90°. Further, during this rotation, body camming surfaces 230 are rotated relative to guiding surfaces 110. In particular, each set of body camming surfaces (eg. 232a, 234a, 236a) is shifted to an adjacent set of guiding surfaces 110 on trolley body 100, the mutual engagement being realised by the moving into mutual abutment of transverse body surfaces 238 against transverse guiding surfaces 118 with an axial movement of body 200, accompanied by a further audible click.
(41) In this configuration, illustrated in
(42) As will be understood, in order to move engagement member 430 back into a position where it can re-engages with shuttle 600, the release member 500 is again operated in the same manner, which moves upper lever surfaces 318 along intermediate lower surfaces 220 to a point at which where upper lever surfaces 318 engage once again with the lower surfaces 212 under the spring force (with an audible click). Following this, as member 500 is released, lever 300 rotates back to its resting position under force of spring 410, and transverse lever surfaces 318 act to drive second transverse surfaces 218 and thus to rotate rotating body 200 by a further 90°. At the same time, during this movement, each set of body camming surfaces (eg. 232a, 234a, 236a) is shifted to the next adjacent set of guiding surfaces 110 on trolley body 100, the mutual engagement being realised by the moving into mutual abutment of transverse body surfaces 238 against transverse guiding surfaces 118 with an axial movement of body 200, again accompanied by a further audible click.
(43) This therefore results in a return to the configuration of
(44) As will be understood, the engagement between rotating body 200 and body camming surfaces 230 provides a one way ratchet with a 90° indexing, while the engagement between lever camming surfaces 310 and the rotating body afford successive rotations of the rotating body by 90°, each successive rotation resulting in an alternation between the two different axial positions of lever 300, due to the different axial offsets provided by the lower 212 and lower intermediate 220 surfaces of the rotating member (which control the position of engagement member 430), as well as an alternation between visible green and red indicia. As will be clear, this provides for engagement and disengagement to be achieved by the same user action, which avoids the need for users to apply different (possibly less intuitive) actions to achieve the desired setting.
(45) Importantly, by requiring that a release must be made with a substantial component of movement in a direction away from door 2, the security of the closure assembly 1 is greatly enhanced, as a purely downward pull on release member 500 or downward pull with a component towards door 2 (such as would result in accessing and pulling it from outside the door) will not result in disengagement of the trolley from the shuttle. It is thus extremely difficult for an unauthorised person who manages to reach and manoeuvre release member 500 from outside the door (eg. with a shaped wire tool introduced between door and frame) to successfully effect disengagement of the door from the drive.
(46) Further, the green and red indicia 205, 206 and the positive engagement into each position (with audible feedback) assist users to determine the state of the engagement member 430, which further assists with regard to ease of use, reliability and security.
Second Embodiment
(47) An alternative embodiment of the present invention is illustrated in
(48) The mechanism to engage and disengage drive between trolley 100′ and shuttle 600′ functions in the same manner as that illustrated and described above with reference to the first embodiment, and will not therefore be described again in detail, other than with reference to differences in particular features and interengagement with additional components specific to this embodiment.
(49) The drawings of the second embodiment show closure arm 4 connected to closure arm bracket 140′ by way of pivoting connection 142′. Further, the second embodiment employs a different form of belt-joiner shuttle 600′. In particular, as can be seen in
(50) In addition,
(51) As most clearly seen in
(52) As shown in the drawings, track latching lever 550′ has a generally planar elongate form, with its pivot position approximately midway along its length. For most of its length it is straight, with a significant portion projecting out of trolley body 100′ in a direction towards garage door 2, terminating in outboard end 554′. Towards the other end, located largely within trolley body 110, it features a downward dog-leg portion 556′ terminating in a generally horizontal inboard end 558′.
(53) Near the upper edge of lever 550′ in the portion projecting out of, but still close to, trolley body 100′, is formed a lateral tab 560′ which projects in a transverse direction relative to lever 550′ (shown most clearly in
(54) The means for engagement and disengagement of trolley 10′ from shuttle 600′ are in most respects as described above with reference to the first embodiment. In particular, trolley body 110′ features a suitably shaped and positioned annular support boss 120′ providing ramp camming guide surfaces against which rotating body 200′ is mounted and urged by spring 410′ (which also serves to return lever 300′ to its rest position once it has been pulled and released). Rotating body 200′ and lever 300′ are provided with suitable ramp camming surfaces to effect the same mechanism, whereby a first full pull on lever 300′ in a direction with a substantial component of movement away from door 2, and subsequent release, serves to rotate body 200′ by 90°, the engagement with support boss 120′ resulting in axial movement of lever 300′ against the force of spring 410′, so moving engagement member 430′ out of engagement with shuttle 600′. A further full pull on lever 300′ in the same direction, with subsequent release, rotates body 200′ by a further 90°, allowing it (by virtue of its engagement with the surfaces of support boss 120′) to return to its original axial position, such that engagement member 430′ projects within shuttle bore 132′ to afford engagement with shuttle 600′.
(55) In this embodiment, as shown most clearly in
(56) The upper face 559′ of lever inboard end 558′ of track latching lever 550′ bears against the outer surface of rotating body 200′, to act as a cam follower. When a cam surface 204′ engages follower face 559′ (ie. the state shown in
(57) Another distinction of this second embodiment of the invention is that engagement member 430′ is received in a blind long slot 610′ (see
(58) As shown in
(59) This mechanism, interacting with the other parts of trolley 10′ and shuttle 600′, provides an automatic latching means for trolley body 110′ when in its normal ‘door closed’ position, as shown most clearly in
(60) When electric motor operator 6 is employed to drive belt 8 to open door 2, belt connector shuttle 600′ moves in a direction towards the drive pinion. The play provided by long slot 610′, within which the end of engagement member 430 is located, allows around 10 mm of movement before shuttle 600′ begins to move trolley body 110. Within this movement, shuttle ramp 604′ engages with the ramp surface of the leading inclined wing portion 562′ of lateral tab 560′, so lifting tab 560′ up on to raised end portion 602′. This has the effect of raising the projecting end of lever 550′, thus disengaging latch hook 564′ from the restraining edge 583′ of latch stop means 580′. This lost motion arrangement means that by the time trolley 10′ begins its movement, driven by its engagement with shuttle 600, latch lever 580′ is in its unlatched position, and follower face 559′ of lever inboard end 558′ is no longer seated on cam surface 204′. Of course, green indicia 205′ remains visible to the user, as body 200′ has not been rotated.
(61) Full or partial opening of door 2 can then follow. When the door is closed again, shuttle 600′ returns trolley 10′ toward its rest position (door closed position), the movement of shuttle 600′ in this direction relative to trolley body 110′ resulting in tab 560′ travelling back down ramp 604′, allowing latching lever 550 (by virtue of ramp edge 555′ and hook 564′) to latch again with latch stop means 580′ once the door is closed.
(62) Selective disengagement of the trolley from the drive for manual operation of door 2 results (as in the first embodiment) in withdrawal of engagement means 430′ and rotation of rotating body 200′ by 90°. This exposes red indicia 207′ to a user, and at the same time the cam action between lobe surface 206′ and follower surface 559′ results in unlatching lever 550′ from latch stop means 580′ (by way of anticlockwise rotation of lever 550′, when viewed as shown in
(63) Alternatively, if release member 500 is actuated when the door is still in an open position, and electric motor operator 6 is actuated, belt drive means 8 will be driven until shuttle 600′ is received by shuttle bore 132′. The rounded end of shuttle 600′ (see
(64) The components of the devices of the two embodiments described and illustrated herein are manufactured from suitable plastics and metal materials. The plastics components may be plastic formed using typical injection moulding processes known in the art, the plastic material selected for suitability for the present purposes. Metal parts may be mild steel or die-cast from a suitable allow such as an aluminium alloy.
(65) In particular, certain parts such as the trolley body and the shuttle may be manufactured from a suitable engineering polymer, such as Dupont's Delrin®, an acetal homopolymer self-lubricating resin material, which is lightweight but durable and has suitable low wear and low friction properties. The rotating body is preferably made from an aluminium alloy, while the latch lever and latch stop components are made from mild steel. The springs are fabricated from music wire steel, all circlips from a suitable spring steel.
(66) In this specification, adjectives such as left and right, top and bottom, upper and lower, first and second, and the like may be used to distinguish one element or action from another element or action without necessarily requiring or implying any actual such relationship or order. Where context permits, reference to a component, an integer or step (or the like) is not to be construed as being limited to only one of that component, integer, or step, but rather could be one or more of that component, integer or step.
(67) The above description relating to embodiments of the present invention is provided for purposes of description to one of ordinary skill in the related art. It is not intended to be exhaustive or to limit the invention to a single disclosed embodiment. As mentioned above, numerous alternatives and variations to the present invention will be apparent to those skilled in the art from the above teaching. Accordingly, while some alternative embodiments have been discussed specifically, other embodiments will be apparent or relatively easily developed by those of ordinary skill in the art. The invention is intended to embrace all modifications, alternatives, and variations of the present invention that have been discussed herein, and other embodiments that fall within the spirit and scope of the above described invention.
(68) It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.
(69) As used herein, except where the context requires otherwise, the term “comprise” and variations of the term, such as “comprising”, “comprises” and “comprised”, are not intended to exclude further additives, components, integers or steps.
(70) TABLE-US-00001 Parts List 1 - Closure assembly 2 - Door 4 - Closure arm 6 - Controller 8 - Drive belt 9 - Track 10 - Trolley 100 - Trolley body 110 - Guiding surfaces 112 - Lower guiding surface 114 - Inclined guiding surface 116 - Upper guiding surface 118 - Transverse guiding surface 120 - Annular support boss 122 - Support boss tubular bore 130 - Shuttle receiving portion 132 - Shuttle bore 140 - Closure arm attachment 150 - Lever aperture 160 - Stop 200 - Rotating body 201 - Rotational central axis 202 - Camming surfaces 204 - Position indicating surfaces (engaged) 205 - (Green) indicia 206 - Position indicating surfaces (disengaged) 207 - (Red) indicia 208 - Rotating body throughbore 212 - Lower surfaces 214 - Inclined surfaces 216 - Upper surfaces 218 - First transverse surfaces 220 - Intermediate lower surfaces (offset setting surfaces) 222 - Second transverse surfaces 230 - Body camming surfaces 232 - Lower body surfaces 234 - Inclined body surfaces 236 - Upper body surfaces 238 - Transverse body surfaces 300 - Lever 310 - Lever camming surfaces 312 - Lower lever surface 314 - Inclined lever surfaces 316 - Upper lever surfaces 318 - Transverse lever surfaces 320 - Lever bore 321 - Annular projection 326 - Spring location notch 330 - Lever end portion 332 - Release member attachment 334 - End stop portion 400 - Engagement assembly 410 - Spring 420 - End plate 430 - Engagement member 440 - Retaining clip 500 - Release member 600 - Shuttle Additional features particular to second embodiment 142′ - Connection to closure arm bracket 550′ - Track latching lever 170′ - Lever boss formation 172′ - Lever pivot pin 174′ - Lever pivot axis 176′ - Lever return spring 552′ - Blind hole (for end of lever return spring) 554′ - Lever outboard end 556′ - Lever dog-leg portion 558′ - Lever inboard end 559′ - Upper face (cam follower) 560′ - Lateral tab 562′ - Tab wing portions 564′ - Hook 602′ - Shuttle raised end portion 604′ - Ramp 610′ - Blind long slot 580′ - Latch stop means 582′ - Top latch plate 583′ - Restraining edge 584′ - Bottom clamping plate 586′ - Bolts 588′ - Front lip 590′ - Upper leading latch ramp 583′ - Rear restraining edge 555′ - Ramp edge of hook