EP1549813B1

EP1549813B1 - Locking device

Info

Publication number: EP1549813B1
Application number: EP03748846A
Authority: EP
Inventors: Jorma Hirvi
Original assignee: Assa AB
Current assignee: Assa Abloy Opening Solutions Sweden AB
Priority date: 2002-10-07
Filing date: 2003-10-06
Publication date: 2009-03-11
Anticipated expiration: 2023-10-06
Also published as: ATE425330T1; AU2003267908A1; SE0202962D0; SE0202962L; EP1549813A1; WO2004031516A1; DE60326614D1; SE524858C2; NO336790B1; NO20052245L

Abstract

A locking device (1) intended to be movably arranged in relation to an engagement means (3), which locking device comprises a hook bolt (15) for engagement with the engagement means and a control element, which hook bolt presents an aperture (21) with an inner surface, and which control element comprises a follower (27) having an eccentric axis of rotation and a peripheral surface. The control element is arranged to transmit motion from an operating means to the hook bolt when the operating means is moved between a locking position and a release position, so that a relative tightening between the engagement means and the locking device is achieved when the operating means is moved to its locking position. In order to prevent breaking up of the locking device, the hook bolt is provided with a securing surface (17b), which is arranged to turn around the engagement means during locking.

Description

Technical field

The present invention relates to a locking device which is intended to be arranged so that it can move in relation to an engaging member and which comprises a hook bolt for engagement with the engaging member and a control member, the hook bolt having a hole with an inner surface, and the control member comprising a follower having an eccentric axis of rotation and a peripheral boundary surface and being designed to transmit movement from an operating member to the hook bolt when the operating member is shifted between a locking position and an opening position, the movement transmitted to the hook bolt producing a relative tightening between the lock and the engaging member when the hook bolt is engaged with the engaging member and the operating member is brought towards the locking position, the hook bolt being pivoted about the follower and the inner surface of the hole in the hook bolt enclosing and interacting with the peripheral boundary surface of the follower, so that rotation of the follower carries the hook bolt with it.
The invention also relates to a combination of a locking device and an engaging member.
The locking device and the combination may be used, in particular, at sliding doors in which it is intended to produce a tightening effect between the sliding door and the door case when closing and a parting effect between the door and the door case when opening, and in which forcing of the lock should be prevented.

Description of the prior art

US 2,599,511 describes a lock for a sliding door, which is designed to slide in a door frame or door case towards and away from an engaging member in the form of a striking plate pin, which is arranged in the door case. The lock is intended for use in sliding doors on railroad cars, for example. In order to ensure a good sealing effect with a sealing strip located on the door case or the door, the lock is designed to produce a tightening of the sliding door against the door case in the car wall when closing. The lock is furthermore intended to have the effect of parting the door from the door case when opening, in order to facilitate opening of the door if icing between the door case and the door, for example, should make the door stiff to open. The lock described comprises a manually actuated operating member, which is pivoted about a first swivel pin extending transversely to the direction of movement of the door and which is fixed to a side plate of the lock. A hook bolt which extends essentially parallel to the direction of movement of the door is arranged at the side of the operating member, viewed in the direction of movement of the door. On one side of the first swivel pin, viewed in the longitudinal direction of the swivel pins, the hook bolt is pivoted about a second swivel pin extending parallel to the first swivel pin and is fixed to the operating member. One end of the hook bolt has a cam surface, which is designed to slide on and past the striking plate pin and has a recess, which is shaped to drop down and engage with the striking plate pin when the door moves towards its closed position. The lock is further provided with members which keep the hook bolt in position so that its cam surface can slide up onto the striking plate pin. The operating member and the two swivel pins are located so that the axis of rotation of the hook bolt moves around the axis of rotation of the operating member when the operating member is operated, a tightening movement being imparted to the hook bolt when the operating member is brought into the closed position and a parting movement when it is brought into the open position. The operating member and the hook bolt furthermore have interacting elements by means of which the end of the hook bolt is lifted off the operating member when this moves to the open position and depressed when the operating member moves to the closed position.
The design described in US 2,599,511 is relatively complicated and is based on the principle that the operating member and the hook bolt are located side by side, that is to say in separate vertical planes which are parallel to the main plane of the door leaf. Such a location results in a number of disadvantages in terms of design and strength. Firstly this side-by-side location means that the entire lock construction is exposed to bending stresses when the parting and tightening force is transmitted via the hook bolt. This applies in particular to the two swivel pins and to the areas in the operating member and the side plate to which the swivel pins are fixed. The location described furthermore places a serious restriction on the thickness of material that can be used in the hook bolt and the operating member for a given maximum width of the lock, at right angles to the main plane of the door. In addition, the location of the two swivel pins side by side means that the maximum diameter of the pins is relatively limited. This in turn places a restriction on the contact surfaces between the swivel pins and the hook bolt, the operating member and the side plate, which leads to high contact pressures with an increased risk of material fractures of these force-absorbing parts of the design construction.
DE 9212765U describes a lock having a hook bolt, which is arranged around an eccentrically supported follower. The hook bolt is formed with an angled hook which engages with an engaging pin in order to achieve tightening and retention.
The lock shown in DE 9212765U has a serious disadvantage in that it is relatively easy to force. By inserting an object between the door leaf and the door case and then forcing the hook bolt upwards by means of the object, it is easily possible to release the engagement of the hook bolt with the engaging pin and hence to force the lock. This known lock has no means of frustrating such forcing.

Summary of the invention

The present invention relates to a lock which allows a tightening force to be applied between a sliding or pivoted door leaf and an adjoining door case or an opposing door leaf when the lock operating member is moved between an opening position and a closing position. An object of the invention is to provide such a lock in which forcing of the lock is rendered considerably more difficult.
Another object is to provide such a lock which also generates a parting force between the door leaf and the door case or between the door leaves when the operating member moves from its closing position to its opening position.
An object of the invention is to provide such a lock which has a simple construction and which overcomes the aforementioned disadvantages in terms of design and strength inherent in hitherto known locks.
These objects are achieved by a lock of the type described in the first part of this description and characterized in that the hook bolt has an engaging surface for producing the relative tightening and a parting surface for producing relative parting between the lock and the engaging member when the operating member is brought towards the opening position, and that the hook bolt has a securing surface, the hook bolt and the follower being designed to allow the engaging surface and the securing surface to rotate around the engaging member when the operating member is moved between its opening position and its locking position, in order to counter any forcing of the locking device.
This provides a simple and reliable way both of tightening and of parting the door leaf when the operating member is moved between its opening and closing position. At the same time the securing surface of the hook bolt together with the rotation of this and the engaging surface about the engaging member make forcing of the lock considerably more difficult. When the engaging and securing surface has rotated around the engaging member, the hook bolt will enclose a larger part of the periphery of the engaging member than the part that is enclosed when the engaging surface first engages with the engaging member. The securing surface especially will mechanically prevent the hook bolt being disengaged from the engaging member. This serves to prevent an object that is inserted between the door leaf and the door case or between the door leaves being used to force the hook bolt up and disengage from the engaging member.
Arranging the hook bolt around the follower, so that force is transmitted by way of the peripheral boundary surface of the follower and the inner surface of the hole, means that it is also possible for the follower and the hook bolt to be situated in the same vertical plane parallel to the main plane of the door leaf. Both the follower and the hook bolt can thereby be made with a thickness of material equal to the internal width of the lock. The design construction furthermore means that only one axis, that is the axis of rotation of the follower, needs to be supported in adjacent force-absorbing members. This single axis is simply supported in the usual way in both of the lock side plates, with the result that no bending stresses occur in the construction when the tightening and parting force is transmitted from the operating member to the engaging member. The design construction also allows the follower and the hole in the hook bolt to be made with relatively large force-transmitting surfaces, which leads to lower contact pressures and hence to a reduced risk of damage or fracture of the components, even if the tightening and parting forces transmitted are large forces.
Further advantages and characteristics of the lock according to the invention are set forth in the following dependent claims and in the detailed description below.
The invention also relates to a combination of a lock and an engaging member which allows the lock according to the invention to be used in sliding doors, to which an oblique component motion is imparted during their closing movement.

Description of preferred embodiments of the invention

An example of an embodiment of the invention is described below with reference to the drawings, in which:

Fig. 1 is a perspective view of an embodiment of the invention and an engaging member, in which certain components have been omitted for greater clarity,
Fig. 2a and 2b show different perspective views and 2c shows a plan view of a striking plate forming part of a combination with a lock,
Fig. 3 is a side view of the lock shown in Fig. 1, without engaging member,
Fig. 4 is a side view to a larger scale of a follower forming part of the lock shown in Fig. 1,
Fig. 5 is a side view to a larger scale of a hook bolt forming part of the lock shown in Fig. 1,
Fig. 6, 7 and 8 show side views of the lock as it assumes different closing and opening positions,
Fig. 9 is a side view of an enlarged detail of the embodiment of the lock and the engaging member shown in Fig. 1,
Fig. 10 and 11 are plan views of a combination of a lock and an engaging member according to the invention.

Fig. 1 shows a first embodiment of a locking device 1 according to the invention. The figure also shows a striking plate 2 with an engaging member 3 in the form of a shackle which is fixed to the striking plate 2. In the following description it is assumed that the lock 1 is fitted in a door and the striking plate 2 in a door case. The lock is particularly suitable for use in sliding doors which are closed and opened by sliding the door in a horizontal or vertical direction, essentially parallel to the main plane of the door leaf. A sealing strip may be arranged on such doors, either on the door case or on a short side of the of the door leaf facing the door caste. In order for the strip to afford a good sealing effect it should be compressed between the door and the door case when the door is closed. For this reason the lock is designed to produce a tightening force between the door and the door case when the door is closed.
The lock 1 is primarily intended to be fitted inset in a door leaf 40 (see Fig. 10). The lock comprises a lock casing 4 laterally defined by two opposing cover plates or side plates 5, only one of which is shown in the figure. The side plate 5 shown in the figure has an internally threaded pin 6, which interacts with screws for holding the two side plates together. When fitted, the lock casing 4 is fixed to a lock faceplate 7 and inset in the door leaf, so that the side plates 5 are essentially parallel to the main plane of the door leaf.
The striking plate 2 (see Fig. 1 and 2a-2c) comprises a fixing plate 8 which is fixed to the door case by means of screws (not shown), which when fitted extend through screw holes 9 in the fixing plate 8. An engaging member in the form of a shackle 3 is fixed to the rear side 8 of the fixing plate and extends through an opening 10 in the fixing plate 8 into the door aperture. The shackle 3 (see Fig. 2a) comprises two side legs 11a, 11b, which at their end facing the door aperture are connected by an engaging part 12. The engaging part 12 has a cam surface 13, which slopes downwards towards the door aperture and is terminated towards the door aperture by a vertical stay surface 14.
Referring again to Fig. 1, the lock 1 comprises a hook bolt 15. The hook bolt 15 is shown more clearly to a larger scale in Fig. 5 and a part thereof to a yet larger scale in Fig. 9. At its free end facing the striking plate 2 the hook bolt 15 has a cam surface 16 and a recess 17, which is open towards the bottom. The recess 17 has an engaging surface 17a which is arranged next to the cam surface 16 of the hook bolt and is terminated at the bottom by a securing surface 17b angled away from the cam surface 16 of the hook bolt. A parting surface 17c is arranged on that side of the recess 17 opposite the engaging surface 17a. The engaging surface 17a and the parting surface 17c are connected by a bearing surface 17d. At the transition between the engaging surface 17a and the securing surface 17b is a retaining shoulder 17e. The end of the securing surface 17b facing the engaging surface 17a will thereby be situated slightly outside the plane of the engaging surface 17a (to the right in the figure).
The hook bolt 15 furthermore has an elongate section 18 which connects the end having the cam surface 16 and the recess 17 to a widened section 19. The elongate section 18 extends through an opening 7a in the faceplate 7, the opening 7a having a lower support surface 7b (see Fig. 1). A torsion spring 20 is arranged around one of the pins 6 and with a leg 20a rests against another pin, so that the other leg 20b of the spring bears against and presses the hook bolt down against the support surface 7b.
A through hole 21 is made in the widened section 19 of the hook bolt (see Fig. 5). The hole 21 has a generally circular cylindrical shape with an inner surface. From the generally circular cylindrical shape a shoulder 22 projects inwards towards the center of the hole 21. The shoulder 22 has two opposing shoulder side surfaces 22a, 22b in the circumferential direction of the hole and an inner shoulder surface 22c facing the center of the hole. An elongate through-recess 23 extends from a lower part of the inner surface of the hole 21 for some distance towards the elongate section 18 of the hook bolt. A compression spring 24 and a steel ball 25 are arranged in the recess 23 (see Fig. 1), so that the coil spring 24 rests against the bottom 26 of the recess and presses the ball 25 towards the hole 21.
A follower 27 is arranged inside the hole 21. In Fig. 4 the follower 27 is shown to a larger scale than the hook bolt 15 in Fig. 5. The follower 27 has a generally circular cylindrical shape with a peripheral boundary surface 28. Over the greater part of its circumference, the outside diameter of the follower 27 is only somewhat smaller than the diameter of the general circular cylindrical shape of the hole 21. In this way the hook bolt 15 can pivot around the follower 27 whilst a large part of the peripheral boundary surface 28 of the follower and the inner surface of the hole 21 interact for the transmission of force. A stop recess 29 is made radially inwards in the peripheral boundary surface 28 of the follower 27. The stop recess 29 includes a circular segment covering approximately 90° and is bounded in the circumferential direction by two essentially radial stop surfaces 29a, 29b. A locking position recess 30 is also made a short radial distance inwards from the stop recess 29. The locking position recess 30 is defined in the circumferential direction by the stop surface 29a arranged in a clockwise direction and by a locking position stop surface 30a, which is arranged at a distance corresponding to the length in the circumferential direction of the inner shoulder surface 22c of the hook bolt. Two retaining position recesses 31a, 31b are furthermore made in the peripheral boundary surface of the follower 27, outside the stop recess 29. These retaining position recesses 31a, 31b are essentially spherical with dimensions corresponding to a part of the spherical surface of the steel ball 25.
The follower 27 furthermore has an eccentrically located integral swivel pin 32 which projects out from both sides of the follower. The swivel pin has a square through-hole 33 in which a handle 34 (see Fig. 6-8) or another operating member can be fixed. The swivel pin is furthermore pivotally supported in opposing openings in the two side plates 5.
The working principle of the lock will be described below with reference to Fig. 6-9. Fig. 7 shows the lock with a latch arm 36, which will be described below, in its latch position. This latch position is assumed only if the latch arm is actively carried there by operation of a lock cylinder 38. When closing the sliding door, the lock is initially in the position shown in Fig. 6. The free end of the hook bolt 15 is in a position protruding from the lock casing 4. The torsion spring 20 presses the hook bolt 15 against the support surface 7b in the lock faceplate 7. The compression spring 24 presses the steel ball 25 into the retaining position recess 31a on the follower 27. The follower 27 and the hook bolt 15 are hereby releasably retained preventing their rotation relative to one another and the handle 34 is thereby held in its horizontal position. The door is now slid towards the door case and the striking plate 2. This can be done either by applying a horizontally directed force to the handle 34 to the left of the figure or, for example, by manually, hydraulically or pneumatically applying a corresponding force to the door leaf or to a handle arranged on the door leaf. When the short side of the door approaches the door case the cam surface 16 of the hook bolt 15 slides up onto the cam surface 13 of the engaging part 12 of the shackle 3, as shown in Fig. 9. The hook bolt 15 and the follower 27, which are still releasably retained in relation to one another and the swivel pin 32 thereby swivel clockwise in bearings provided in the side plates 5 for the swivel pin 32. Under this movement, the handle 34 pivots somewhat downwards in a clockwise direction. When the down-turned tip of the securing surface 17b in the recess 17 of the hook bolt has passed the engaging part 12 of the shackle 3, the torsion spring 20 presses the free end of the hook bolt downwards so that the bearing surface 17d of the recess 17 is brought to rest against the top side of the engaging part 12. The hook bolt 15, the follower 27, the swivel pin 33 and the handle 34 then swivel counterclockwise and reassume the position shown in Fig. 6.
It is from this position that the tightening movement is initiated. By applying a counterclockwise force to the handle 34, the swivel pin 33 and the follower are made to rotate counterclockwise. The free end of the hook bolt 15 is prevented from moving downwards since the bearing surface 17d bears against the engaging part 12 of the shackle 3. The spring force of the compression spring 24 is thereby overcome and the steel ball 25 is released from its retained position in the retaining position recess 31a. The follower 27 can then rotate freely in relation to the hook bolt 15. Since the axis of rotation of the follower 27 is arranged eccentrically and since the hook bolt 15 is arranged around the follower 27, the center of the hole 21 in the hook bolt 15 and hence the axis of rotation of the hook bolt will move along a circular line about the axis of rotation of the follower. A horizontal movement to the right of the figure is then imparted to the free end of the hook bolt 15, which cannot move downwards. The engaging surface 17a of the recess 17 of the hook bolt 15 engages with the engaging part 12, so that further horizontal movement to the right of the figure is prevented by the hook bolt. Continued counterclockwise turning of the handle 34 now means that the widened section 19 of the hook bolt moves inwards/upwards in relation to the lock casing 4, so that the door in which the lock-casing is fixed moves towards the striking plate 2. This tightening movement continues until the stop surface 29a of the follower 27 comes into contact with the side shoulder surface 22a of the shoulder 23 in the hole 22 in the hook bolt (see Fig. 7, 4, 5). As a result of the radially directed force acting between the peripheral boundary surface of the follower and the inner surface of the hole, the shoulder 22 then assumes a locking position in which the inner shoulder surface 22c is situated in the locking position recess 30 of the follower. If a horizontal force is applied to the door in the opening direction, this prevents the door to open, since the side shoulder surface 22b bears against the locking position stop surface 30a of the locking position recess 30.
Since the widened section 19 of the hook bolt 15 also moves upwards during the tightening/locking movement, the free end of the hook bolt will rotate around the engaging part 12, so that the securing surface 17b will to a certain extent enclose the underside of the engaging part 12. In this way the hook bolt will be mechanically latched on engagement with the engaging member. If an object that is inserted between the door leaf and the door case is used in an attempt to force the hook bolt 15 upwards, the securing surface 17b will come into contact with the engaging member 3, this contact mechanically preventing further relative movement upwards between the hook bolt 15 and the engaging member 3. Angling the securing surface 17b away from the free end of the hook bolt (towards the right in the figure) ensures that the mechanical contact between the securing surface 17b and the engaging member actually occurs if the hook bolt 15 is pressed upwards, even though a certain degree of play exists between the engaging surface 17a and the engaging member 3 when the hook bolt 15 is initially forced upwards. This securing effect is further enhanced in that the end of the securing surface 17b facing the engaging surface 17a is displaced by a distance equal to the height of the retaining shoulder 17e from the plane of the engaging surface 17a. If the engaging member has a sharp edge facing the engaging surface 17a, this edge will come into mechanically latching contact with the retaining shoulder 17e if the hook bolt 15 is forced upwards. If the engaging member has a circular or otherwise curved cross-section, on the other hand, the retaining shoulder 17e will be able to pass a part of the engaging member, with the result that the latching mechanical contact instead occurs between the inclined securing surface 17b and the engaging member 3. This represents a simple and effective way of countering an attempt to force the lock by applying an upwardly directed force to the hook bolt in proximity to its free end.
When the lock has assumed this locking position, the handle 34 is in a vertical position as shown in Fig. 7. The handle 34 is retained in this vertical position in that the follower 27 and the hook bolt 15 are again releasably retained preventing their rotation relative to one another when the steel ball 25 is pressed into the second latch position recess 31b in the peripheral boundary surface of the follower 27.
If the door, from the starting position shown in Fig. 6, is pulled closed with great force, so that the sealing strip between door and door case is compressed by this closing force, it can happen that the lock passes through the sequences described above without any counterclockwise tightening force having to be applied to the handle.
Starting from the locking position illustrated in Fig. 7, it will now be described how the door is opened. The figure shows the latch arm 36 described below in its latch position. On opening the door, however, this latch arm must be in its release position, which is shown in Fig. 8. To release the lock, a clockwise force is applied to the vertically aligned handle 34. The follower 27 then rotates clockwise. The hook bolt 15, however, is still prevented from rotating since the securing surface 17b of the recess 17 is still engaged with the engaging part 12. The spring force of the compression spring 24 is thereby overcome and the steel ball 25 is forced out of the retaining position recess 31b, with the result that the follower 27 and the hook bolt 15 are again able to rotate freely in relation to one another. At the same time the shoulder 22 is forced out of its locking position in the locking position recess 30 and can then slide freely in the stop recess 29 of the follower. The torsion spring 20 presses the hook bolt 15 down so that the bearing surface 17d in the recess 17 bears against the engaging part 12. As the follower 27 continues to rotate clockwise, a horizontal movement is imparted to the free end of the hook bolt 15, outwards from the lock casing 4. The parting surface 17c of the recess 17 then comes into engagement with the vertical stay surface 14 of the engaging part 12, with the result that a parting force is imparted to the door which causes it to move away from the striking plate 2. At the same time the widened section 19 of the hook bolt 15 moves downwards, so that the free end of the hook bolt 15 swivels clockwise around the engaging part 12. The engagement of the securing surface 17b around the engaging part 12 is thereby released.
When the follower has rotated to the position shown in Fig. 6, the hook bolt 15 assumes a horizontal, projecting position. In this position the steel ball 25 is again pressed into the retaining position recess 31a in the peripheral surface of the follower 27. Under the continued clockwise rotation of the follower 27, the stop surface 29b of the follower comes into contact with the side shoulder surface 22b of the shoulder 22 so that the hook bolt is made to rotate about the axis of rotation of the follower 27. The clockwise force applied to the handle 34 overcomes the spring force of the torsion spring 20 with the result that the free end of the hook bolt is raised so that the lower tip of the securing surface 17b escapes from the top of the engaging part 12 and the door can be pushed open. The lock has then assumed the position shown in Fig. 8 and when the clockwise force on the handle 34 is withdrawn, the lock returns to the position shown in Fig. 6 in that the torsion spring 20 forces the hook bolt to bear the support surface 7b of the faceplate 7. Since the steel ball 25 is pressed into the retaining position recess 31a, the follower and the handle follow to the positions shown in Fig. 6.
The lock according to the invention may be provided with a latch arm 36, which is pivoted between a release position shown in Fig. 6 and 8 and a latch position shown in Fig. 7. In the latch position, one end of the latch arm 36 engages with a locking recess 37 on the widened part 19 of the hook bolt 15, thereby preventing all movement of the hook bolt from its retracted locking position. Movements of the latch arm are controlled by a lock cylinder 38, which is operated by means of a key or a handle (not shown) in the usual way.
The invention also relates to a combination of the lock described above and an engaging member. A preferred embodiment of the combination according to the invention is described below with reference to Fig. 10, 11, 2a, 2b and 2c. Since the lock according to the invention has been described above the following description of the combination will concentrate on the engaging member.
Fig. 10 and 11 show a sliding door 40 in which the sealing effect between the door 40 and door case 41 is not produced between the short side 42 of the door leaf and a side of the door case facing the door aperture. Instead, the sealing effect here is achieved between a surface 43 of the door leaf 40 which is parallel to the main plane of the door leaf and arranged in proximity to the short side of the door leaf facing the striking plate and a corresponding parallel surface 44 of the door case. A sealing strip 45 can be arranged between these two surfaces. In the example shown the sealing strip is fitted to the door case but it may also be fitted to the door leaf.
In order to produce a good sealing effect on such sliding doors, in its displacement towards the closed position not only must the door 40 move parallel to the main plane of the door towards the door case, but a component motion must also be imparted in a normal direction to the main plane of the door leaf. This can be produced, for example, by arranging wedge-shaped guide members 46 in the door case 41 or in grooves outside the door case, said guide members 46 guiding the door during its displacement travel towards the closed position. These guide members 46 force the door 40, as it nears the closed position, to move obliquely in towards the stop in the door case. One problem that occurs in the use of the tightening and parting lock according to the invention, as described above, in such doors is that conventional engaging members do not permit any oblique movement.
This problem is resolved by the combination according to the invention. Fig. 2b shows how the shackle 3 is fixed to the fixing plate 8. At their ends remote from the engaging part 12 the two side legs 11a and 11b are joined to a generally V-shaped piece 11c, which extends through the opening 10. A vertical through-hole 47 is made in the V-shaped piece 11c. A pin 48 is arranged through the hole and fixed to the side of the fixing plate 8 remote from the door aperture. The inside diameter of the hole 47 is somewhat larger than the outside diameter of the pin 48, so that the shackle 3 can swivel about the pin 48. The shackle 3 is kept in the vertical position by the underside of the V-shaped piece 11c bearing against the bottom edge of the opening 10. Fig. 2c shows a plan view of the shackle 3, the fixing plate 10 and the pin 48. The figure shows that a vertical surface 12a of the engaging part 12, which is remote from the door aperture, has a convex shape 12b curving away from the door aperture.
When the combination of lock and engaging member according to the invention is used in sliding doors to which, at the end of their closing movement, a component motion is imparted transversely to the main plane of the door leaf, the lock functions as described above. During the tightening phase the engaging surface 17a of the hook bolt 15 engages with the vertical surface 12a of the engaging member 12. When the door 40 approaches its closed position and an oblique movement is imparted to it in the direction of the sealing strip 45, the shackle 3 will swivel about the pin 48 whilst the convex shape 12b of the vertical surface 12a of the engaging part 12 allows the engaging surface 17a of the hook bolt to roll over the convex vertical surface. The door 40, the lock 1 and the hook bolt 15 are thus allowed to move sideways in relation to the striking plate 2 and the engaging part 12 without any lateral forces or bending stresses occurring on the hook bolt 15, the striking plate 2 or the engaging member 3.
An example of an embodiment of the locking device and the combination of a locking device and an engaging member according to the invention have been described above. The invention naturally lends itself to variations within the scope of the following patent claims. For example, the lock can be located in the door case and the engaging member in the door. The lock according to the invention can also be used in swiveling hinged doors instead of sliding doors. The door handle 34 described above may be replaced by other manually actuated operating members or ones actuated electrically, pneumatically or hydraulically, for example. The lock may furthermore be designed with or without the latch mechanism comprising the latch arm 36 and the lock cylinder 38.

Claims

A locking device (1) which is intended to be arranged so that it can move in relation to an engaging member (3) and which comprises a hook bolt (15) for engagement with the engaging member (3) and a control member (27), the hook bolt having a hole (21) with an inner surface, and the control member (27) comprising a follower (27) having an eccentric axis of rotation and a peripheral boundary surface (28) and being designed to transmit movement from an operating member (34) to the hook bolt (15) when the operating member is shifted between a locking position and an opening position, the movement transmitted to the hook bolt producing a relative tightening between the lock and the engaging member when the hook bolt is engaged with the engaging member and the operating member is brought towards the locking position, the hook bolt being pivoted about the follower and the inner surface of the hole in the hook bolt enclosing and interacting with the peripheral boundary surface of the follower, so that rotation of the follower carries the hook bolt with it, characterized in that
the hook bolt (15) has an engaging surface (17a) for producing the relative tightening and a parting surface (17c) for producing relative parting between the lock and the engaging member when the operating member is brought towards the opening position and that
the hook bolt (15) has a securing surface (17b), the hook bolt and the follower (27) being designed to allow the engaging surface and the securing surface to rotate around the engaging member (3) when the operating member (34) is moved between its opening position and its locking position, in order to counter any forcing of the locking device.
The locking device as claimed in claim 1, wherein the engaging surface (17a) and the parting surface (17c) are formed as two opposing sides of a recess (17), which is made in the hook bolt (15) in proximity to the free end thereof facing the engaging member (3).
The locking device as claimed in claim 1 or 2, wherein the securing surface (17b) is formed as an inclined extension of the engaging surface (17a).
The locking device as claimed in any one of claims 1 to 3, wherein a retaining shoulder (17e) is arranged between the engaging surface (17a) and the securing surface (17b).
The locking device as claimed in any one of claims 2 to 4, wherein the engaging surface (17a) and the parting surface (17c) are formed as two essentially parallel opposing sides of the recess and are connected by a bearing surface (17d).
The locking device as claimed in any one of claims 2 to 5, wherein the recess (17) is essentially U-shaped and the engaging surface (17a) is longer than the parting surface (17c)..
The locking device as claimed in any one of claims 2 to 6, wherein the securing surface (17b) extends from the engaging surface (17a) towards the plane of the parting surface (17c).
The locking device as claimed in any one of claims 1 to 7, wherein the hook bolt (15) comprises a cam surface (16) which is designed to slide on the engaging member (3).
The locking device as claimed in any one of claims 1 to 8, wherein the follower- (27) has an essentially cylindrical part, the circumferential surface of which constitutes the peripheral boundary surface (28) of the follower, each end boundary surface of the essentially cylindrical part of the follower and the hole (21) in the hook bolt (15) lying in essentially the same plane.
The locking device as claimed in any one of claims 1 to 3, wherein stop surfaces (29a, 29b) are arranged on the peripheral surface of the follower (27), said stop surfaces interacting with side surfaces (22a, 22b) which are arranged on a shoulder (22) of the hook bolt (15), said shoulder projecting inwards into the hole (21) in order to transmit rotational movement from the follower (27) to the hook bolt (15), and a recess (30) made radially inwards in the peripheral surface of the follower being arranged between the stop surfaces (29a, 29b) in order to receive the shoulder (22) when the hook bolt (15) is in a retracted locking position.
The locking device as claimed in any one of claims 1 to 10, wherein the hole (21) in the hook bolt (15) is a through-hole and that the follower (27) has a through-shaft (32) which is pivotally supported in a lock casing (4) surrounding the hook bolt and the follower, the through shaft (32) having means (33) for coupling the operating member (34).
The locking device as claimed in any one of claims 1 to 11, wherein means (23, 24, 25, 26, 31a, 31b) are designed to releasably prevent relative movement between the follower and the hook bolt in two retained positions.
Combination of a locking device as claimed in any one of claims 1 to 12 and an engaging member (3), wherein the engaging member (3) is pivoted about a vertical axis of rotation (48).
The combination as claimed in claim 13, wherein the engaging member (3) comprises a convex surface (12b) which is designed to engage with an engaging surface (17b) of a recess (17) in the hook bolt (15).