Technical field The present invention relates generally to locks and in particular to a lock device comprising a cylinder house and a cylinder plug arranged in the cylinder house.

Background

Locks of the abovementioned type are manoeuvred by means of a matching key, which can be inserted into a key way arranged in the cylinder plug. The key's action on the pins arranged in the cylinder plug and in the cylinder house releases the cylinder plug and allows the cylinder plug to be turned relative to the cylinder house.

The cylinder house is usually mounted for use in a lock case. The lock case typically comprises a lock mechanism which, via mechanical coupling between the lock mechanism and the cylinder plug, permits manoeuvring of a dead bolt arranged in the lock case when the cylinder plug is turned.

In order to fix the cylinder plug in the cylinder house, a securing member is generally arranged at the end of the cylinder plug protruding from the cylinder house. Examples of such securing members are, for instance, a circlip received in a peripheral groove in said protruding end.

A disadvantage of the above solution is, for example, that when an attempt is made to remove the cylinder plug mounted in the cylinder house by exerting force in the axial direction, the securing member may be radially deformed by expansion of its opening that surrounds the cylinder plug. In this way, the cylinder plug can be released from the cylinder house. Summary

A first object of the present invention is to make available a lock device that improves security against manipulation of the lock device.

Another object of the present invention is to make available a lock device that permits the use of a more reliable type of cylinder plug without structurally changing the cylinder house.

The present invention is based on the recognition by the inventor that, instead of arranging a securing member on an end protruding from the cylinder house, the securing member can be at least partially arranged on the cylinder plug inside the cylinder house when the cylinder plug is in the mounted position. The interior of the cylinder house thus counteracts expansion of the securing member when a strong axial force is applied to the cylinder plug, which can occur, for example, during manipulation aimed at removing the cylinder plug from the cylinder house. Moreover, the inventor has also recognized that, by providing the rear end of the securing member with a radially projecting flange, existing cylinder house designs do not have to be adapted to a cylinder plug and a securing member according to the invention.

In accordance with the invention, a lock device is made available comprising: a cylinder house with a through-opening, a cylinder plug, which can be received in the through- opening and serves for rotatable engagement with the cylinder house, which cylinder plug has a first end portion comprising a threaded outer peripheral surface, and a securing member with a through-opening, which securing member has a first portion where the peripheral surface of the through-opening is threaded for engagement with the threaded outer peripheral surface of the first end portion, and a flange which has a cross-sectional dimension greater than a cross- sectional dimension of the through-opening, and the first portion of the securing member is designed to be received in the through-opening of the cylinder house, with the flange bearing against an outer wall of the cylinder house.

By making available a lock device in which the securing member that secures the cylinder plug in the cylinder house has a portion arranged in the cylinder house, the cylinder house can counteract radial expansion of the securing member when a strong axial force is applied to the cylinder plug. In particular, the walls of the through-opening of the cylinder house can counteract radial expansion of the first portion of the securing member.

Moreover, the cylinder house does not need to be modified in order to avoid the cylinder plug being removed from the cylinder house from the front. In the mounted state, the flange of the securing member bears against the outer wall of the cylinder house and is therefore not received in the through-opening. A function of the flange, achieved by bearing against the rear outer wall of the cylinder plug, is to prevent the cylinder plug from being able to be removed via the front of the cylinder house. With the design according to the invention, therefore, the cylinder house does not need to be adapted to receive the securing member. In particular, the through-opening does not need to have a first internal diameter in order to receive the cylinder plug and a second, greater internal diameter in the portion for receiving the securing member.

The first end portion of the cylinder plug can have a first external diameter, and a central portion of the cylinder plug can have a second external diameter, which is greater than the first external diameter.

The design of the cylinder plug means that the cylinder house does not have to be modified in order to be able to receive said portion of the securing member. In particular, this can be achieved by virtue of the fact that the second external diameter can be substantially the same size as the external diameter of the first portion of the securing member.

The first portion of the securing member can be cylindrical. The cylindrical shape means that the first portion can be easily turned in the through-opening.

The end surface of the first end portion of the cylinder plug can have a screw hole, in which case the lock device, in the mounted state, further comprises a screw received in the screw hole, which screw hole is arranged such that a part of the head of the screw bears against the inner peripheral surface of the flange in order to secure the flange to the cylinder plug. The cylinder plug and the securing member are secured to each other in this way, the result of which is that relative rotation between the cylinder plug and the securing member can be avoided. This reduces the risk of the securing member being unscrewed or released from the cylinder plug upon repeated rotation of the cylinder plug. The screw head can have a conical surface designed to bear against the inner peripheral surface of the flange. The conical surface can increase the contact surface between the inner peripheral surface of the flange and the screw head. The increased contact surface means that relative rotation between the cylinder plug and the securing member can be more effectively avoided.

The inner peripheral surface of the flange can be conical in the axial direction. Upon engagement with a conical screw head, this therefore increases the resistance force against relative rotation occurring between the cylinder plug and the securing member. The flange can have at least one groove in the radial direction, in order to permit rotation of the securing member relative to the cylinder plug. In this way, the securing member can be easily mounted on the cylinder plug by means of a tool that engages with said at least one radial groove.

One embodiment can further comprise a washer which, in the mounted state, is arranged between the end surface of the end portion and the screw head of the screw, in order thereby to prevent manipulation of the lock device. This therefore reduces the risk of manipulation around the rear end of the lock via the key way of the cylinder plug. The cylinder plug can have an integrated tailpiece. By making available a cylinder plug with an integrated tailpiece, the manufacturing process can be simplified, and the tailpiece can have improved strength compared to a tailpiece that is mounted thereon. The risk of manipulation is also reduced since the integrated tailpiece means that there are no openings around the tailpiece in the rear end surface of the cylinder plug, through which openings manipulation could occur.

The lock device according to the invention can advantageously be used together with a lock case in order thereby to form a lock.

Further objects and advantages of the invention will become clear from the following detailed description and from the claims. Description of the figures

An illustrative embodiment of the invention is described in detail below with reference to the figures, of which:

Fig. 1 shows a perspective view of a lock device according to the invention,

Fig. 2 shows an exploded schematic view of the lock device from Figure 1,

Fig. 3a shows a plan view of the rear face of the lock device from Figure 1, and Fig. 3b shows a partially cutaway side view of the lock device from Figure 1.

Detailed description Figure 1 shows a lock device 1 according to the invention. The lock device 1 comprises a cylinder house 3, a cylinder plug 5 (shown only schematically here by broken lines in order to illustrate that it is received in the cylinder house 3), and a securing member 9.

Figure 2 shows an exploded schematic view of the lock device 1 from Figure 1. The cylinder house 3 has a first plane outer wall 13-1. The cylinder house 3 has a second plane outer wall 13-2. The first outer wall 13-1 and the second outer wall 13-2 are arranged on opposite sides of the cylinder house 3. The first outer wall 13- 1 defines a side of the cylinder house designed to receive a key. The second outer wall 13-2 defines a rear face of the cylinder house 3 designed to bear against a lock case. The cylinder house 3 has a through-opening 15. In the mounted state, the cylinder plug 5 is arranged in the through-opening 15. The cylinder plug 5 is introduced into the through-opening 15 from the side of the cylinder house 3 that has the first outer wall 13-1, from the direction A.

The second outer wall 13-2 has a cylindrical part 14-1 projecting axially from the second outer wall 13-2. The projecting part has a flange contact surface 14-2 parallel to the second outer wall 13-2.

The cylinder plug 5 has a key way in which a key can be inserted from a direction A for the purpose of manoeuvring the cylinder plug 5. The cylinder plug has an end surface 6 which, when the cylinder plug 5 is in the mounted state in the cylinder house 3, projects out of the cylinder house 3. The end surface 6 defines an end of the cylinder plug 5 opposite the end that defines the opening of the key way.

The cylinder plug 5 has a tailpiece 7 arranged at the end surface 6 and integrated with the cylinder plug. The tailpiece 7 comprises two parallel projections separated by a spacing. The tailpiece 7 is arranged to engage with a follower arranged in a lock case. The rotation force to which the cylinder plug 5 is subjected when the cylinder plug 5 is turned relative to the cylinder house 3 is transmitted mechanically by the follower to a tailpiece in a lock case. By mechanical coupling, the tailpiece conveys the rotation force onwards for manoeuvring a dead bolt arranged in the lock case.

The cylinder plug 5 has three portions extending in the axial direction, each with a different cross-sectional dimension. A first end portion 5-1 has a threaded outer peripheral surface 5'-l. The first end portion 5-1 has a first external diameter dl .

The next cylinder plug portion is the central portion 5-2 of the cylinder plug 5. The central portion 5-2 has a group of pin openings 8, which run through the cylinder plug to the key way. The central portion 5-2 has a second external diameter d2, which is greater than the first external diameter dl.

The central portion 5-2 is connected to a second end portion 5-3. The second end portion 5-3 is arranged on an opposite side of the central portion 5-2 from the first end portion 5-1. The second end portion 5-3 has an external diameter d3, which is greater than the external diameter d2 of the central portion 5-2. The second end portion 5-3 thus defines a cylinder-shaped flange of the cylinder plug 5.

The through-opening 15 has an end portion with a cross- sectional dimension greater than the cross-sectional dimension d4 of the rest of the through-opening 15. This end portion has a cross-sectional dimension substantially the same size as the external diameter d3 of second end portion 5-3. The end portion is designed to receive the second end portion 5-3 of the cylinder plug 5. When the cylinder plug 5 is arranged in the cylinder house 3, a radial surface 5' -3 of the cylinder plug 5 bears on a corresponding radial surface of the through-opening 15 where the cross-sectional dimension merges directly into the cross-sectional dimension d4. This design prevents the cylinder plug 5 from being able to move axially towards the rear face of the cylinder house 3 as defined by the second outer wall 13-2.

In the illustrative embodiment described, all of said cross-sectional dimensions are diameters. Said cross- sectional dimensions are therefore circular or substantially circular.

The securing member 9 has a cylindrical first portion 9-1 and a second portion formed by a flange 9-2. The flange 9-2 is cylindrical and projects radially relative to the first portion 9-1. A through-opening extends through the first portion 9-1 and the flange 9- 2.

The through-opening of the securing member 9 has an internal diameter substantially the same size as the external diameter dl of the first end portion 5-1. The first portion 9-1 has an inner peripheral surface 9-3 which is threaded. The securing member 9 can therefore be arranged around the threaded first end portion 5-1 of the cylinder plug 5. In this position, the threads of the first end portion 5-1 engage with the threads in the peripheral surface 9-3.

The first portion 9-1 of the securing member 9 has an external diameter d5 substantially the same size as the internal diameter d4 of the through-opening 15. The first portion 9-1 of the securing member 9 can therefore be introduced into the cylinder house 3. The peripheral surface of the through-opening 15 of the cylinder house 3 thus limits the radial expansion possibilities of the first portion 9-1 of the securing member 9 when acted on axially by the cylinder plug 5.

The securing member 9 has two radial grooves 10-1 and 10-2 in the end surface of the flange 9-2. Each groove 10-1 and 10-2 runs across the entire radial extent of the end surface of the flange 9-2. In the grooves 10-1 and 10-2, tools can engage with the securing member 9 in order to allow the cylinder plug 5 and the securing member 9 to be screwed together.

The flange has a cross-sectional dimension d6 greater than the cross-sectional dimension d4 of the through- opening 15 of the cylinder house 3. When the securing member 9 is located in the mounted position, the flange 9-2 thus bears against the flange contact surface 14-2. This is shown in Figure 3b.

Returning to Figure 2, the end surface 6 of the cylinder plug 5 has a screw hole 11, in which a screw 19 can be screwed. A washer 17 can be secured to the end surface 6 by the screw 19. The washer 17 has two side recesses 17-1 and 17-2 designed to receive the two projections of the tailpiece 7. The washer 17 has a recess 17-3 for receiving the screw 19.

The head of the screw 19 is preferably cone-shaped. The screw hole 11 preferably has a cone-shaped opening designed to receive a cone-shaped screw head. The peripheral inner surface 9-4 of the flange 9-2 converges in the axial direction towards the first outer wall 13-1. This increases the contact surface between the cone-shaped screw head and the peripheral inner surface 9-4 which, in the mounted position, bears against the cone-shaped screw head. The screw hole 11 is arranged near the periphery of the end surface 6 in order to ensure that the head of the screw 19 will bear against the peripheral inner surface 9-4. The fixing of the securing member 9 and of the cylinder plug 5 by means of the screw 19 avoids the securing member 9 and the cylinder plug 5 coming loose from each other upon repeated turning of the cylinder plug 5, for example by means of a key. Figure 3a shows clearly how the screw 19 bears against the peripheral inner surface 9-4 of the flange 9-2.

Figure 3b shows a partially cutaway side view of the lock device 1. The figure shows the cylinder plug 5 received in the cylinder house 3. The securing member 9 is mounted on the cylinder plug 5. It can be seen in particular that the flange 9-2 bears against the flange contact surface 14-2. This design avoids the cylinder plug 5 being able to be removed by force from the cylinder house 3.

An illustrative embodiment of the invention has been described above. The invention is not limited to this embodiment and can instead be freely varied within the scope of the attached claims. For example, the flange can have a non-circular cross section. It suffices that the flange has a cross-sectional dimension greater than the diameter d4 of the through-hole. Moreover, the cylinder house can have a substantially plane rear outer wall, against which the flange can bear. In a variation of the invention, the tailpiece, instead of being integrated with the cylinder plug, can be mounted onto the cylinder plug.