BACKGROUND There is a large demand for lock devices that are both inexpensive and easy to produce and mount. Among other forms of lock devices, this applies to coin locks used in general establishments, such as bathing facilities and sports (athletics) centres. Neither can locks that afford poor security be accepted, since this can result in broken locks, stolen keys, and so on.

One problem associated with certain present day lock devices is that they are much too expensive to manufacture and to mount.

SUMMARY OF THE INVENTION One object of the present invention is to provide a lock device of simple construction that includes solely a few component parts but that, nevertheless, affords a sufficiently high degree of security with regard to the purpose for which it is intended.

Another object of the present invention is to provide a lock cylinder and a lock cylinder mounting method that are simpler than those available with present day technology.

The invention is based on the realization that a lock cylinder can be fixated with the aid of fixating means that block movement of the cylinder in a radial direction, and by designing the inner end-part of the cylinder plug so that when the lock cylinder is used, the plug is fixated against axial movement by engagement in a mounting hole.

A lock device as defined in claim 1 is therefore provided in accordance with the invention.

The invention also relates to a lock cylinder mounting method as defined in claim 10, and to a lock cylinder as defined in claim 11. Further preferred embodiments are made apparent in the accompanying dependent claims.

A lock device according to the invention can be produced very cheaply and is very easy to mount, as a result of the small number of simple component parts.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail by way of example and with reference to the accompanying drawings in which Fig. 1 is a perspective front view of a lock device according to the invention; Fig. 2 is a perspective rear view of the lock device, which includes a cap and a cover plate; Fig. 3 is a rear perspective view of the lock with the cover plate removed;

Fig. 4 is an oblique exploded rear view of the components included in the lock device; Fig. 5 is an oblique exploded front view of the components included in the lock device, with the exception of the cap; Fig. 6 is an exploded view of the components of a lock cylinder according to the invention; Fig. 7 illustrates part of a cylinder plug included in the lock cylinder shown in figure 6; Figs. 8 a-c are cross-sectional views of the lock cylinder shown in figure 6; Fig. 9 is a detailed illustration of a cylinder housing included in the lock cylinder; Fig. 10 is a detailed illustration of a cylinder mounting hole and fixating pins used in mounting the lock cylinder; Figs. 11 a-c illustrate respectively the position of an anchoring part of the cylinder plug in the process of mounting the lock cylinder; Fig. 12 shows the inner surface of the cover plate, and the parts mounted thereon; Fig. 13 is a view from above of the rear side of the lock device with the cover plate removed; Fig. 14 and 15 show the coin opening shutter of the lock device in an open and a closed position respectively; Fig 16 is a detailed illustration of the lock mechanism of the lock device;

Fig. 17 and 18 are plan views of the rear side of the lock device showing the insertion of a valid coin in a retracted and extended position of a lock bolt respectively.

Fig. 19 is a plan view of the rear side of the lock device showing the insertion of an invalid coin in the retracted position of a lock bolt; Fig. 20 illustrates a transport safety device adapted for use with said lock device.

Fig. 21 shows the placement of the transport safety device of figure 20 of said lock device; and Fig. 22 illustrates a bolt element in an alternative embodiment of a lock device according to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Preferred embodiments of a lock device and a lock cylinder according to the present invention will now be described, firstly with reference to figure 1. In this description the expression"mounting of the lock cylinder"relates to attachment of the cylinder in the lock housing, and the expressions"mounting and attachment"will be used alternatively. This also applies to the expressions "dismantling"and"releasing".

Figure 1 is a perspective front view of a lock device in the form of a coin lock, generally referenced 1. The coin lock includes a housing or a casing, of which a plastic cap 10 is shown in the figure. The upper side of the cap includes a coin insertion opening 11 and the lower part of the front side of the cap includes a coin return opening 12. The lock device also includes a bolt element, of which an outwardly protruding bolt 31 is shown in the figure. The lock device <BR> <BR> is intended to be fastened, e. g. , to the inside of a locker

door or cupboard door, wherein the housing is provided, to this end, with four through-penetrating holes 13 intended for receiving a respective screw. A through-hole 15 in the cap is adapted for the use of a tool by means of which a key bit that has broken off in the lock cylinder can be removed, as described hereinafter.

Figure 2 is a perspective view of the rear side of the lock device 1, i. e. that side which faces towards the door to which the lock device is fitted. A plastic cover plate 20 is mounted on the inside of the cap 10, for instance with the aid of snap-fastening means, so as to cover the internal parts of the lock device. Although not shown, the cover plate includes a through-penetrating hole in which a lock cylinder 40 is mounted. The lock cylinder is received in a through-penetrating hole in the door to which the lock device is fitted so that it is accessible to a user from outside the door.

Figure 3 is a perspective rear view of the lock device 1 with the cover plate dismantled.

All of the components of the lock device are shown in respective exploded views of figures 4 and 5. In addition to the parts 10, cover plate 20, bolt element 30 and lock cylinder 40, the lock mechanism also includes a slide 50 which is mounted for sliding movement in grooves 32 provided on respective sides of the bolt element to this end. The slide is held in place in said grooves, by means of a slide spring 51.

As will be seen from figure 4, two fixating pins 23 project out at right angles from the cover plate above the lock cylinder mounting hole, the function of said pins being explained below.

The lock device also includes a shutter 60 which is forcibly guided desmodromically via two shutter pins 33 on the upper side of the bolt element A follower 70 is rotatably mounted on an outwardly protruding follower ring 21 on the inside of the cover plate, as shown in figure 5. The follower ring surrounds the aforesaid holes 22 in the cover plate, for accommodation of the lock cylinder 40. The follower includes a follower pin 71 intended for co-action with an elongate follower pin-hole 34 in the bolt element, so as to impart linear movement to the bolt element upon rotation of the follower. The follower is spring biased by means of a follower spring 72.

Finally, the lock device includes a hook 80 which functions to prevent movement of the bolt element when an invalid coin is inserted into the lock device. When mounting the lock cylinder and when transporting the lock device, the hook is held in position by means of a transport safety element 90.

Attachment of the lock cylinder 40 to the cover plate 20 will now be described with reference to figures 6-lla, b. As will be seen from the exploded view of figure 6, the lock cylinder includes a cylinder housing 41 that has an opening 41a for rotatable mounting of a cylinder plug 42. The plug includes typically spring-biased top and bottom pins, both referenced 43. A key-receiving slot 42a extends axially along the plug. A groove 42b is machined in the barrel surface of the plug transversely to its axial direction. The groove extends to a pre-determined extent around the cylinder plug and is intended for co-action with a latching pin 44 which, when fitting the lock cylinder, is fixed in place in a hole 41b provided in the cylinder housing for this purpose. The groove 42 b machined in the cylinder plug will best be seen from figure 7, which shows the cylinder

plug 42 in detail. It will be seen from figure 7 that the inner end of the plug, i. e. the end facing towards the lock housing, has an anchoring part 42c of non-circular cross- sectional shape. The anchoring part is separated or distinguished from the circular-cylindrical part of the cylinder plug by a circumferentially extending waist part 42d.

The latching pin 44 has several functions. Firstly, it locks axial movement of the inserted cylinder plug. This will be evident from the cross-sectional views in figures 8 a c, which have been taken through the lock cylinder 40 at the level of the machined groove 42b and the latch pin 44. It will be seen that the latch pin engages the groove, thereby preventing the axial movement of the plug.

Secondly, the latch pin restricts rotational movement of the cylinder plug by an inserted user key, as shown in figure 6 at reference 45. This user key has an unbroken spine surface 45a on the key bit. With this groove configuration, counter rotation is blocked completely from the starting position shown in figure 8a, since the barrel surface of the cylinder plug blocks all further rotation. Rotation through about 90 degrees to a locking position of the lock cylinder is permitted in a clockwise direction, whereafter the spine of the key-bit of the inverted user key blocks all further rotation, see figure 8b. When inserting a service key, as illustrated in figure 6 at reference 45', greater clockwise rotation is permitted than that permitted with the user key, due to the fact that the spine surface of the service key includes a recess which, when the key is inserted, is located at the height of the latch pin. This means that even in the event of clockwise rotation the barrel surface of the cylinder plug that blocks further rotation will permit

rotation from the position shown in figure 8a through about 125 degrees clockwise, see figure 8c.

When using lock devices it happens that a key inserted into the cylinder plug sometimes breaks off. As a safeguard against such an event, the cap 10 includes a through- penetrating hole 15 of small diameter, about one mm (see fig. 1) into which a slender object can be inserted and then passed through a corresponding hole 39 in the lock element 30 (see for instance fig. 13) and finally into the plug 42.

This enables a broken key that has fastened in the key slot 42a to be pushed out with the bolt element 30 in an extended position, therewith facilitating maintenance of the lock device.

Figure 9 is a detailed illustration of the rear side of the cylinder housing 41. As will be seen from the figure, two axial bores or holes 41c are provided in the cylinder housing at the end surface that faces towards the cover plate, in addition to the through-penetrating hole 41a for receiving the cylinder plug 42. These bores are intended to receive a respective perpendicularly and outwardly protruding fixating pin 23 positioned above the mounting hole 22. As will be clearly seen from figure 10, these fixating pins are integrated with the cover plate 20. When the cover plate is made from a low-strength material, such as a plastic material, the fixating pins 23 are preferably strengthened with a respective inner metal pin 23a.

It will be realized that when the cylinder housing 41 is fitted over the fixating pins 23, so that the pins are inserted into the bores 41c, the cylinder housing will be fixed against movement parallel to the plane of the cover plate. Since the clearance between pins and holes is very small, the cylinder housing will be guided by the pins so

that said housing will extend generally at right angles to the plane of the cover plate.

Figure 10 shows the configuration of the mounting hole 22 on the cover plate 20. The mounting hole is non-circular in shape and includes two straight, mutually parallel edges 22a and two curved edges 22b which join the straight edges. This shape harmonizes with the cross-sectional shape of the anchoring part 42c that constitutes the inner part of cylinder plug. The circumferential waist part 42d of circular cross-section has a diameter corresponding to the relative distance of the straight edges of the mounting hole 22, so that when inserting the cylinder housing, the mounting hole 22 will be level with the cover plate, thereby allowing rotation of the cylinder plug.

The fundamental concept of the lock cylinder fastening arrangement is as follows. This will be best be seen from figures lla-c, in which the orientation of the anchoring part 42c is shown in broken lines and the mounting hole 22 is shown in full lines. In the mounting process, the mounted cylinder plug 42 with inserted key is rotated through 125 degrees in a clockwise direction, so that the cross-section of the anchoring part 42c will harmonize with the open area of the mounting hole 42, see figure llc. The anchoring part is then pushed into the mounting hole at the same time as the cylinder housing 41 is fitted to the fixating pins 23.

The cylinder plug is then turned to its original position, see figure lla, wherewith the anchoring part locks the cylinder plug and therewith the entire lock cylinder against withdrawal in an axial direction. Since the fixating pins lock the lock cylinder against radial movement, the cylinder is totally fixated.

gure llb shows the anchoring part in a cylinder locking ) sition, where the bolt element is in a fully extended ducking position. It will be seen here that the anchoring art blocks withdrawal of the cylinder plug from the hunting hole 22.

Ks explained above with reference to figures 8a-c, rotation Df the cylinder plug required for the insertion of the anchoring part into the mounting hole can only be achieved when a recess-provided service key is used, and consequently such a key is used when mounting the lock cylinder. It will be understood that the same applies when dismantling a mounted lock cylinder. Thus, there is obtained a solution which enables dismantling of an already mounted lock cylinder, which solution can be utilized when wishing to re- code a lock for instance. An old lock cylinder can simply be replaced with a new lock cylinder that includes a different key code, with the aid of service keys. There is also a need, at times, to switch lock cylinders between different doors or different localities.

The inventive mounting method enables a lock cylinder to be mounted quickly in a simple fashion, without requiring parts other than the actual lock cylinder and the structure to which it shall be mounted.

The modus operandi of the mechanism accommodated in the lock housing will now be explained in detail with reference to figures 4,5 and 12-19. The generally circular follower 70 is mounted on the follower ring 21 (see figure 5) on the inside of the cover plate 20 (see figure 12). The anchoring part 42c of the cylinder plug extends into a central anchor opening 72 in the follower, which has a shape which harmonizes with the cross-sectional shape of the anchoring part. The follower therewith rotates with the cylinder plug.

The follower spring 72 is mounted between a spring pin 24 on the cover plate 20 and a spring pin 73 on the follower 70.

The follower spring functions as an alternator spring and has two functions. Firstly, the spring biases the follower so that the bolt element will be held in a fully retracted position, i. e. will not protrude from the locked housing, which would otherwise be liable to damage the lock device and the door frame when closing the door in which the lock device is mounted. Secondly, the follower spring overcomes the resistance exerted by the slide spring when the bolt element is in a fully extended locking position.

The cover plate 20 also carries two stop shoulders 25 and 26. These shoulders limit rotation of the follower in one direction to 125 degrees, i. e. the mounting position of the cylinder plug, owing to the fact that those parts of the follower where the follower pin 71 and the spring pin 73 are located extend beyond the general circular shape of the follower. Due to the provision of two generally opposite stop shoulders that together restrict rotation of the follower, possible oscillations of the follower, and therewith the lock cylinder are prevented when rotation of the cylinder plug is stopped by the stop shoulders. The stop shoulders 25 and 26 fully block rotation in the other direction.

As earlier mentioned, the slide 50 is slidably mounted in the grooves 32 on respective sides of the bolt element 30, see the plan view of figure 13. The slide is held in position and is spring biased to the position shown in figure 13 by means of the slide spring 51, which is tensioned between a seating surface 35 on the bolt element and a seating surface 52 on the slide.

The elongate shutter 60 is placed above the bolt element, see figure 14. The shutter includes two shutter pin openings 62 which are of identical shape and which accommodate a respective shutter pin 33. The shutter pin openings consist of two laterally displaced grooves 62a, 62b that are mutually connected via an oblique groove 62c. The shutter pins 33 have a rhomboidal cross-sectional area and are able to slide along the full extent of the shutter pin openings.

This results in a large wear surface and therewith a long length of life. It will be noted from figure 13 that the shutter 60 is unable to move longitudinally, i. e. to the left or to the right in the figure. On the other hand, it is able to move sideways.

The shutter functions in the following way. When the bolt element is fully withdrawn, as shown in figure 14, the shutter allows a coin (not shown) inserted into the coin opening 11 to fall down to an intended position in the lock mechanism. When the bolt element moves from its retracted position, shown in figure 14, to a fully extended locking position, shown in figure 15, the shutter will move sideways in the direction of the arrow, such as to prevent insertion of a coin into the coin lock. As a result of this very simple construction, there is obtained a shutter that effectively prevents access through the coin opening when the bolt element is located in a fully extended locking position. It will be understood that when movement of the shutter is blocked, for instance, by an object placed in the coin opening, movement of the bolt element will also be blocked, therefore making manipulation of the coin lock difficult to achieve. The shutter will have blocked the coin opening completely already when an attempt is made to manipulate the lock in the absence of a coin, where movement

of the bolt element is stopped by the hook having come into contact with a stepped surface.

Returning to figure 13, it will be seen that the U-shaped hook 80 is pivotally mounted at one end portion 81 in a perforated projection 14 on the inside of the cap 10. The other end portion 82 of the hook projects into a stepped window 36 in the bolt element. In the inwardly retracted position of the bolt element 30 shown in figure 13, the other end part 82 of the hook rests on the lower edge of the window 36. Extension of the bolt element to locking position is therewith prevented by engagement of the hook with the lower"step"of the window.

Figure 16 illustrates the window 36 in more detail and shows the inwardly retracted bolt element 30 and also part of the slide 50. Also shown is the placement of a first coin pin 37 mounted on the bolt element and a second coin pin 53 mounted on the slide. In the figure 16 illustration the two coin pins are spaced apart at a distance at which a valid coin inserted into the coin lock will be held firmly between the pins. An obliquely extending coin guiding rib 38 on the bolt element guides further downward movement of the coin.

As will be seen from figure 16, the slide 50 is also provided with a stepped surface 54 where a first step 54a and a second step 54b are on the same height level as the step 36a, 36b of the stepped surface on the bolt element, although slightly offset laterally. The precise function of the steps will be described below with reference to figure 17 and 18.

In a lock starting position, shown in figure 17 with the key in the position shown in figure 8b, the bolt element 30 is retracted in the cap 10. When a valid coin is inserted into

the coin insertion opening, the coin will drop down to lie between the two coin pins 37 and 53. The respective positions of the coin and the coin pins are shown in broken lines in the figure. When the follower 70 is caused to rotate anti clockwise, corresponding to rotation of the key from the position shown in figure 8b to the position shown in figure 8a, the bolt element is caused to move linearly to the left in the figure, by virtue of the follower pin 71 engaging in the follower pin hole 34. The follower pin and its movement path are also shown in the figure.

Because a valid coin of the correct size has been placed as shown, the hook 80, and more specifically its second end- part 82, will"climb"on the coin as the bolt element moves outwards. This climbing process is continued until the hook reaches above the uppermost steps 36b, 54b on the bolt element and the slide respectively; see also figure 16. In the last part of the extension or outward projection of the bolt element, the slide is retained by the hook 80, but not the bolt element. This is because the two steps are mutually offset laterally, as before mentioned. This results in an increase in the distance between the two coin pins 37,53.

When this distance is greater than the diameter of the coin, the coin will drop down to the position shown in figure 18.

Movement of the coin is controlled by the obliquely extending rib 38 on the side of the bolt element; see figure 16 for instance. This is followed by full extension of the bolt element.

When the lock is later unlocked and the bolt element returns to the position shown in figure 17, the coin drops down from the position shown in figure 18 and is accessible via the coin return opening 12.

The coin insertion opening 11 is dimensioned so that invalid coins of excessively large diameter cannot be inserted into the coin lock. An invalid coin whose diameter is smaller than the relative distance between the coin pins 37,54 will drop straight through the lock mechanism and become accessible through the coin return opening 12. If an invalid coin which although much too small in diameter is suf- ficiently large to fasten between the coin pins 37,54 it is inserted to the coin opening, the coin opening will have the contour shown in figure 19. In this case, the end part 82 of the hook 80 will grip the stepped surface 54 on the slide 50, that is the upper most step 54b, prior to the hook reaching over the upper most step. As a result, the slide will remain stationary whereas the bolt element 30 will continue its movement to the left in the figure as a result of the mutual offset of the steps. This causes the relative distance between the coin pins 37,53 to increase and results in the invalid coin falling down and becoming accessible via the coin return opening 12. Further movement to the fully extended locking position of the bolt element 30 is not permitted, due to the engagement of the hook with the stepped surface of the bolt element. Further rotation of the follower 70 and therewith also of the cylinder plug 42, is blocked and removal of the key from the lock cylinder 40 is not allowed. It is thus not possible to lock the device when an invalid coin is inserted into said lock.

Figure 17 shows the position of the follower pin 71 in a fully retracted position. When dismantling the lock cylinder 40 from the cover plate there is used, as before mentioned, a service key which allows further rotation of the cylinder plug 42 from the retracted position. This is made possible by the fact that the follower pin hole 34 extends downwardly of the position of the follower pin shown in figure 17.

Because the follower pin hole continues to an extent equal to downward movement of the follower pin, there is no further movement of the bolt element.

The function of the transport safety device 90 will now be explained with reference to figures 20 and 21. The transport safety device is shown in detail in figure 20 from which it will be seen that the device comprises an upper, large pull loop 91, and a lower, smaller hole loop 92 with a stem 93 extending between said loops. The device also includes a thickening 93a on the stem 93. Figure 21 shows the transport safety device when fitted. With the pull loop located outside the lock housing, the stem 93 extends through a slot on the upper side of the cap and down to the hook 80, where the safety device is caused to hang-up the hook by placing the holder loop 92 around the second end-part 82 of the hook. This enables the bolt element to be moved between an outwardly extended state and an inwardly retracted state without having inserted a coin into the lock, since the hook has been lifted up over the steps. This function is desirable prior to putting the lock device into operation.

A first preferred embodiment of a lock device according to the present invention has been described above. It will be understood, however, that the described device can be modified within the scope of the accompanying claims. For example, there has been described a lock cylinder that can be dismantled. It will be understood, however, that the lock cylinder construction can be further simplified by enabling the lock mechanism to block rotation to the lock dismantling position instead of the described latch pin. An example of how this can be achieved is illustrated in figure 22, in which a bolt element is provided with a follower pin hole 34'that is shorter than the hole in the first preferred

embodiment. Because of the shortness of this follower pin hole, the follower will not rotate to said dismantling position and the lock cylinder is therewith permanently mounted. This enables the use of a typical lock cylinder that is able to rotate through 90 degrees.

The lock cylinder is fitted to the cover plate in the same way as that in the case of the first embodiment, whereafter the lock mechanism, including follower and bolt element, is assembled. The cylinder plug can not thereafter be rotated to the dismantling position, in which the plug anchoring part is in alignment with the mounting hole, unless the whole of the lock is dismantled.

Although mounting of the lock cylinder has been described in relation to a coin lock, it will be understood that the lock cylinder according to the invention and mounting of the cylinder can also be applied with other types of locks.

Although the inventive lock device has been described as consisting mainly of a plastic material, it will be understood that any appropriate material may be used to this end, such as metal. etc.

Although there has been shown a lock device intended for a right hand door, it will be understood that the invention can also be applied with respect to left hand doors, wherewith the lock components will be in mirror image to those shown in the figures. It may be beneficial to provide the slide 50 with two coin pins, one on each side. This would allow the slide to be used in lock devices for both right hand and left hand doors.

Although two fixating pins 23 have been illustrated and described, it will be understood that solely one fixating pin will suffice in fixing the lock cylinder against

movement in a radial direction, even though two fixating pins provide greater support for the mounted lock cylinder.

A mounting hole 22 of specific shape has been illustrated and described. It will be understood, however, that the mounting hole may have a non-circular shape that would allow the anchoring part of the cylinder part to be inserted into a plug mounting position, but that will prevent axial movement of the plug in a plug fixating position. It will also be understood, however, that in the majority of configurations the waist portion of the cylinder plug must have a diameter that is smaller than the smallest relative distance between two opposing edges of the mounting hole.

With regard to the function of the mounting hole, it is important that the configuration of the hole, the anchoring part and the waist portion are such that when in a plug mounting position the anchoring portion will permit the block cylinder to move axially so as to enable the anchoring portion to be inserted into the mounting hole, and such that the anchoring part will engage with the lock housing in a cylinder plug fixating position, thereby preventing axial movement of the lock cylinder.

Although the shutter pins 33 have been shown with a rhomboidal cross-sectional shape, it will be understood that these pins may have another cross-sectional shape, such as a circular shape.

Moreover, although a shutter that has two shutter pin openings has been shown, it will be understood that a shutter that has only one or more than two openings would function in the same way as that described.