Latch with adjustable cam

The present invention relates to a latch for arrangement on a door and locking the door relative to a door frame is provided. The latch comprises an attachment part configured to be arranged on the door, a latch shaft extending from the attachment part, and a cam arranged on the latch shaft, wherein the latch shaft, when the latch is arranged to the door, is rotatable relative to the door to rotate the cam between an open position in which the door is openable relative to the door frame, and a closed position in which the door is locked to the door frame. The cam can be in an open state or in a locked state, and the axial position of the cam on the latch shaft is adjustable when the cam is in the open state.

TECHNICAL FIELD

The present disclosure relates to a latch for a door, and especially a latch for a door with an adjustable cam.

BACKGROUND

A conventional latch for a door usually has custom-made measurements for arrangement on a specific door, meaning that the latch is customized for a specific distance between a door and a door frame, the door being in a closed state. The latch is usually also provided to fit a specific thickness of a door.

Different doors having varying measurements lead to a need for a specific latch arrangement for a specific door, depending on the thickness of the door and the offset distance between the door and the door frame. The latches need do be custom-made in order to fit specific door arrangements, leading to a need for producing many different latches for closing, opening and locking the doors. This poses a problem, thus producing many different latches for different doors is both cost and time inefficient.

Hence, there is a need for a more efficient and flexible system of providing door latches to be arranged on doors with different dimensions.

SUMMARY

It is an object of the present invention to provide an improved solution that alleviates the mentioned drawbacks with present devices. Furthermore, it is an object to provide a latch for a door having properties suiting different door arrangements in an efficient way. That is, creating a more secure connection between the door frame and the door with no need for a latch device being specifically dimensioned for doors with different measurements and doors and door frames with different offset distances. Thereby, by providing a latch with an adjustable cam, a reduction of manufacturing time and costs due to an all-round solution may be achieved. The latch being adjustable may also provide a well-fitting solution for many doors. The invention is defined by the appended independent claims, with embodiments being set forth in the appended dependent claims, in the following description and in the drawings.

According to a first aspect of the invention, a latch for arrangement on a door and locking the door relative to a doorframe is provided. The latch comprises an attachment part configured to be arranged on the door, a latch shaft extending from the attachment part, and a cam arranged on the latch shaft, wherein the latch shaft, when the latch is arranged to the door, is rotatable relative to the door to rotate the cam between an open position in which the door is openable relative to the door frame, and a closed position in which the door is locked to the door frame. The cam can be in an open state or in a locked state, and the axial position of the cam on the latch shaft is adjustable when the cam is in the open state.

By the axial position being adjustable when the cam is in the open state is meant that the cam may be adjusted in its axial position relative to the latch shaft, more specifically along the latch shaft. When the desired position is achieved, the latch cam may be brought into a closed state and thereby fixate the latch cam in a position wherein the latch is secured to function as intended. In the closed state of the cam, the cam may be both axially and rotationally fixed relative to the latch shaft. In the open state, the cam may be adjustable at least axially relative to the latch shaft. By the cam having an open state and a closed state it may be meant that the cam itself may be structurally or functionally changed to be brought into either of the states. It may be that a part of the cam is moved, operated or manipulated to bring the cam into the closed state to fix the axial position of the cam, or into the open state to enable axial adjustment of the cam.

According to an embodiment, the cam comprises an openable cam lock, wherein in an unlocked position of the cam lock, the cam is in the open state and is axially moveable relative to the latch shaft, and in a locked position of the cam lock, the cam is in the locked state and is axially fixed relative to the latch shaft. The cam lock may be operated by a user with the intention to bring the cam into the open position or the closed position. The cam lock may thereby enable an adjustment of the axial cam position to fit the present door and door frame arrangement. The cam lock may provide an easy operation to bring the cam into the locked state or the open state.

According an embodiment, the cam may comprise an opening through which the latch shaft is configured to extend. In the locked position of the cam lock the width of the opening may be reduced compared to the unlocked position.

An advantage of the above embodiment is that the distance between the cam and the attachment part is adjustable, enabling attachment to doors with different arrangement relative a door frame without the need of providing a different latch with specific dimensions separately for each door and door frame arrangement. Another advantage is that the latch shaft can be effortlessly assembled manually.

According to one embodiment, the cam may comprise a lock slit extending from the opening to the cam lock. The cam lock may be provided as a snap lock. The lock slit may enable the cam lock to be closed more easily and to provide a more secure fit when fixing the latch shaft.

According to another embodiment, the cam lock, in the locked position, may be configured to press the parts of the cam at respective sides of the lock slit to at least partly close the lock slit.

The lock slit may provide two arms extending on respective sides of the lock slit from the opening towards the cam lock. The two arms may provide extensive flexibility for widening or for tightening the opening. The widened opening may facilitate assembling and adjustment of the cam on the latch shaft. When the cam lock is locked, the two arms may be pressed towards each other so that the lock slit is reduced.

According to one embodiment, the cam may comprise at least one additional slit extending from the opening. The additional slits may provide flexibility in the size of the latch opening, thereby further improving the function of the cam lock fixating the axial position of the cam when in the locked position.

According to another embodiment, the latch shaft may comprise a plurality of indentations axially separated, and wherein the cam may comprise, at an inner surface of the opening, at least one projection configured to interact with at least one of said indentations when the cam is in the locked state. The projection may be shaped to effectively interact with an indentation. The projection may extend radially from the inner surface towards a center of the opening. The projection may interact with an indentation when the cam is in the locked state in a way that the cam is axially fixed relative to the latch shaft. In the open state of the cam, the cam may be axially moveable along the latch shaft to be aligned with either of the indentations. By having one projection on the inner surface of the opening on the cam, and a plurality of indentations axially spread out along the latch shaft, the cam may in its locked state by axially fixed relative to the latch shaft in a plurality of axial positions, corresponding to the number of axially separated indentations on the latch shaft.

According to a further embodiment, the plurality of indentations may be arranged as a first section in which the indentations may be axially separated and circumferentially aligned along the circumference of the latch shaft. The indentations in the first section may thereby be provided in a row along the longitudinal extension of the latch shaft. All indentations in the first section may be configured to interact with a common projection, providing different axial positions of the cam along the latch shaft. The latch shaft may further comprise an additional second section of indentations comprising a plurality of axially separated indentations circumferentially aligned along the circumference of the latch shaft. The indentations of the two sections may further be circumferentially separated. The cam may further comprise at least two projections on the inner surface of the opening at positions along the circumference of the opening corresponding to the circumferential positions of the first and second sections of indentations. By having two or more sections of indentations along the circumference of the latch shaft, configured to interact with corresponding two or more projections on the cam, the fixation of the cam along the latch shaft when the cam is in the locked position may be further stabilized.

The indentations may be formed as substantially half-ellipsoidal, half-spherical, rectangular or any other shape adapted to receive a correspondingly shaped projection or projections on the cam.

According to one embodiment, the latch may comprise an opening in the cam which is circular shaped with a cut flat portion, and the latch shaft may have a cross-sectional shape being circular with a cut flat portion. The latch of this embodiment may have an advantage of providing a secure fastening of the latch shaft, preventing the shaft from rotating in relation to the cam. The cross-sectional shape of the latch shaft may correspond to the shape of the opening in the cam. The prevention of rotation of the cam relative to the latch shaft further provides an alignment of any projection on the inner surface of the opening with indentations on the latch shaft.

In one embodiment, the attachment part may comprise an indication means to indicate the direction of the cam. This direction may be the same direction as the cut flat portion of the latch shaft and the opening in the cam. The indication means may provide the advantage of indicating the position of the cut flat portion, to help with the installation of the latch lock.

According to a further embodiment of the latch, there may be at least one projection at the inner surface of the opening in the cam, arranged on the cut flat portion of the opening, and a first section of indentations on the latch shaft may be arranged on the cut flat portion of the latch shaft. Interacting projection and indentations on the cut flat portion of the otherwise circular latch shaft and opening may provide an improved interaction function between the two components.

According to one embodiment, the cam may extend in a direction perpendicular to the longitudinal extension of the latch shaft. The cam may extend in said direction in a first portion and a second portion. The first portion may be configured to be attached to the latch shaft and the second portion may be configured to, when in use, interact with the door frame in the closed position. The second portion may be offset the first section along the direction of the longitudinal extension of the latch shaft. The offset portions of the embodiment may provide an option to use the latch cam in reversed directions, creating a further variation in distance, providing for a larger variety of different embodiments of doors and door frames.

According to one embodiment, the latch may comprise a cam having an end portion thereof which is configured to, when in use, interact with the door frame in the closed position, comprising a hold projection configured to interact with a corresponding opening or recess which may be provided in the door frame.

The recess or opening may be designed to interact with the hold projection in a pliable way, allowing the interaction to occur in a way providing a secure locking or closing of the door. By secure locking or closing it is meant that the user may be provided with visual, sensible or auditory confirmation of the closing/locking of the door. The interaction between a hold projection and a recess or opening on the door frame may further prevent unintentional rotation of the latch from the closed position of the door towards the open position of the door.

According to a second aspect of the present invention, a door arrangement is provided, comprising a door frame, a door openable relative to the door frame, and a latch according to any of the embodiments presented above. The door arrangement may be configured to enable or prevent opening of the door relative to the door frame when in the open position or in the closed position.

DESCRIPTION OF EMBODIMENTS

FIG.1illustrates the latch1according to an embodiment of the present invention. The latch1comprises an attachment part10, a latch shaft20and a cam30. The attachment part10is configured to attach the latch1to a door2. The attachment part10comprises resilient flanges12which fixes the latch1to the door2when the latch1has been arranged thereto. The attachment part10is, when the latch1is arranged to the door2, pressed through a hole in the door2, such that the resilient flanges12are pressed inwards towards a center of the attachment part10. When the resilient flanges12have passed through the hole in the door2, they spring out to an initial position, preventing the attachment part10to be removed from the hole. The attachment part10further comprises an attachment ring14. When the attachment part10is arranged to the door2, the attachment ring14is arranged on an outside of the door2, while the resilient flanges12are arranged at an inside of the door2. Together, the attachment ring14and the resilient flanges12fix the attachment part10and the latch1to the door2. The attachment ring14comprises an indicator16showing the direction of the cam30. The attachment part10further comprises an actuator means18. The actuator means may be a key hole, a handle, a tool actuator or the like, configured to be operated by a user to rotate the latch1.

The latch shaft20is attached to the attachment part10. The latch shaft20and the latch shaft10are rotationally fixed relative to each other. Hence, when the actuator means18is operated to rotate the latch1, the latch shaft20is rotated. The latch shaft20has a cross-section being circular with a cut flat portion22. The latch shaft20extends along a longitudinal direction X.

The cam30extends along a direction Y being perpendicular to the direction X. The cam30comprises an opening37through which the latch shaft20extends. The cam30is openable using a cam lock33. The cam lock33can be opened and closed to and from an opened position and a closed position. In the closed position, the opening37is smaller than in the open position. The latch shaft20extending through the opening37is thereby locked relative to the cam30when the cam lock33is in the closed position.

From the opening37to the cam lock33, a lock slit35extends. The lock slit35provides two arms extending on respective sides of the lock slit35from the opening37towards the cam lock33. In the closed position, the cam lock33provides the two arms to be pressed towards each other, reducing the width of the lock slit35. To additionally provide flexibility in the size of the opening37when the cam lock33is either closed or open, the cam30comprises one or more additional slits36extending from the opening37. The additional slits36may extend towards an edge of the cam30.

The cam lock33is provided in the form of a snap lock. As further illustrated inFIGS.6and7, the cam lock33comprises a hook member331which is configured to snap onto a catch member332in the closed position of the cam lock33. The hook member331is arranged on a lip member335which is connected to the rest of the cam30via a hinge333. The hinge333may be formed from a thickness of the material of the cam30necessary to provide the desired hinge function. The cam lock33further comprises a stop member334arranged behind the lip member335. The stop member334is configured to prevent the lip member335from being lifted or opened too far which might otherwise cause damage to the cam lock33, or conflict with other parts of a door arrangement.

The opening37is circular with a cut flat portion39. This shape of the opening37provides, in combination with the corresponding shape of the cross-section of the latch shaft20, that the latch shaft20is rotationally fixed relative to the cam30, and that the latch shaft can be inserted into the opening37in only one predetermined rotational position.

The latch shaft20comprises at least one groove section. In the illustrated embodiment, the latch shaft20comprises three groove sections24a,24b,24c. Each groove section24a,24b,24ccomprises a plurality of grooves. The grooves in a groove section24a,24b,24care axially separated along the longitudinal direction X of the latch shaft20. The grooves may be axially separated but arranged axially adjacent to each other. The grooves of a groove section24a,24b,24cextend along a common portion of the circumference of the latch shaft20. The grooves of a groove section24a,24b,24care separated along the circumference of the latch shaft20from the grooves of another groove section24a,24b,24c. A first groove section24ais arranged on the cut flat portion of the latch shaft20.

The cam30comprises, at an inner surface of the opening37, one or more projections38. The number of projections38correspond to the number of groove sections24a,24b,24con the latch shaft20. Each projection38is elongated along the circumference of the opening37. Each projection38extend along a portion of the circumference of the opening37. In case of several projections38a,38b,38c, the projections are separated from each other along the circumference of the opening37. One projection38ais arranged on the cut flat portion39of the opening. All projections38a,38b,38care arranged at a common axial level in the opening37.

The cam30comprises a first portion31at which the opening37through which the latch shaft20extends is provided. The cam further comprises a second portion32which interacts, when the latch is arranged to a door2and is in the closed position, with the door frame3. The cam30extends in a direction Y being perpendicular to the longitudinal direction X of the latch shaft20. The second portion32of the cam30is offset the first portion31along the direction X.

As seen inFIGS.3and4, the adjustability of the axial position of the cam30along the latch shaft20provides that the latch1can be adapted for different sizes and configurations of door frames3. Depending on the distance between a door plane of the door2, when the door2is closed, and door frame surface towards which the cam is intended to abut, the configuration of the latch needs to be different. By adjusting the axial position of the cam30, the one and the same latch1can be used for different door and door frame configurations.

Further, due to the offset of the second portion32of the cam30, and that the cam can be flipped relative to the latch shaft20, the range of possible door and door frame configurations which the latch1can be used for is further increased. As seen inFIG.3, the cam30is in the most extended axial position, and the cam30is flipped to an arrangement providing the longest possible distance between the door2and the door frame3. InFIG.4, the cam30is in the axial position closest to the attachment part10, and the cam is flipped to an arrangement wherein the second portion32is offset towards the door2, thereby providing the shortest possible distance between the door2and the door frame3.

On the second portion32of the cam30, either if the second portion32is offset the first portion31or not, it may comprise, at an end of the cam30, a hold projection34. As further seen inFIG.10, the hold projection34is intended to interact with an opening4on the door frame3. When the latch1is in the closed position, the hold projection's interaction with the opening thereby prevent unintended movement of the latch1towards the opened position.

FIG.11illustrates a latch1according to an embodiment of the present invention, in which the cam30extends straight perpendicularly relative to the latch shaft20. Hence, the first portion31and the second portion32of the cam are not offset relative to each other.

FIG.12illustrate a cam30according to an embodiment where the cam30comprises a recess51. The recess extends along at least a part of the second portion32of the cam30. The recess51may further extend over a transition portion between the second portion32and the first portion31. The recess51may have a depth at the second portion that is about half of the thickness of the cam31at the second portion32. At the recess' extension at the transition portion, the depth of the recess may gradually decrease in a direction towards the first portion31. The recess51may improve the properties of the cam30during manufacturing, such as preventing deformation or shrinking. It may further provide stability to the cam30.