Child safety seat with headrest height adjustment mechanism

A child safety seat includes a seat shell, a headrest, a guiding component, slidably coupled to the seat shell, for guiding a strap of an integral harness system, and an adjustment mechanism for adjusting the height of the headrest. The adjustment mechanism includes a coupling element which is configured to be placed in a first and a second configuration, and, when placed in the first configuration, the coupling element couples the headrest with the guiding component such as to allow for movement of the headrest together with the guiding component relative to the seat shell. When placed in the second configuration, the coupling element couples the seat shell with the guiding component to prevent the guiding component from movement relative to the seat shell and to allow for movement of the headrest relative to the seat shell.

This application claims priority to European application number 17001495.5 filed Sep. 6, 2017, the entire contents of which are hereby incorporated by reference in its entirety.

The invention relates to a child safety seat with an adjustment mechanism for adjusting the height of the child safety seat's headrest. In particular, the invention relates to a combination child safety seat with an anti-misuse mechanism which prevents a user from using the child safety seat in integral mode too long and from using the child safety seat in non-integral mode too early.

Smaller children, such as babies or toddlers, are held firmly in their safety seat mounted on a passenger seat of a vehicle with a special restraint device, such as an integral harness system. For this age group, a safety seat with a 3-point or 5-point harness using a harness buckle as a coupling device is the safest way to travel. The 3-point or 5-point harness of the safety seat firmly secures shoulders and hips of the child in the seat. In order to properly secure the child with the 3-point or 5-point harness, it is important that the shoulder straps of the harness are properly guided over the child's shoulders so that in the case of a front collision the body of the child is efficiently restrained and decelerated. In addition, in order to protect the child's head, the headrest of the child seat needs to be correctly adjusted so that the forces from the impact are deviated from the head.

In order to facilitate the adjustment of the shoulder straps and the headrest in accordance with the child's size and age, some of the known child safety seats comprise an adjustment mechanism that couples the harness and the headrest. Because of this, the adjustment of the headrest causes the correct adjustment of the harness and vice versa.

Older children can use the 3-point adult seat belt with a highback booster seat, as this correctly positions the 3-point adult seat belt over the child's body. Also such child seats comprise a height adjustable headrest.

From the above, child safety seats can either be used with an integral harness system or in connection with the safety belts of a vehicle for restraining a child in the child safety seat. Child safety seats which use means directly connected to the vehicle, such as adult seat belts, for restraining the child, fall into the so-called non-integral class.

There exist also so-called combination child seats, or so-called group 123 child seats. Combination child seats allow to combine different safety systems for smaller children and for older children in one seat. When used for a smaller child, the integral harness system of the combination child seat is used to secure the child. This is the so-called integral mode. The integral harness may be either a 3-point or a 5-point harness. The 3-point harness comprises two shoulder straps. At one end portion of each shoulder strap there is connected a tongue adapted to engage with a harness buckle. The other ends of each shoulder strap are coupled to the combination child seat. The 5-point harness comprises also two straps. One end of each strap is connected to the seat base of the combination child seat. A buckle tongue is slideably connected to each strap. The buckle tongues are inserted into the harness buckle for securing the child. The portion of the strap running from the seat base to the tongue is guided over the hips/thighs of the child. The portion of the straps running from the tongue to the backrest of the combination child seat is guided over the shoulders of the child. When the child gets older, it is secured in the combination child seat by the safety belt of the vehicle. Then, the integral harness system can be stowed away. This is the so-called non-integral mode. The combination child seat can be used over a larger range of child's ages.

Integral mode starts at an age of about 1 year and ends at about 4 years or more. Non-integral mode starts at an age of about 3 years and ends with 12 years. Thus, there is an overlap range between approximately 3 and 4 years in which the child safety seat can be used either in integral mode or in non-integral mode. Because of this, there exist several potential sources of misuse. This is, the child safety seat might be used too long in integral mode. Likewise, the change from integral mode to non-integral mode might have been performed too early. Performing the change from integral mode to non-integral mode outside the above mentioned overlap range from approximately 3 to 4 years drastically increases the risk of severe injuries of a child in a vehicle accident, if the child safety seat is not used in the appropriate mode.

In addition, the transmission of known combination child seats from the integral mode to the non-integral mode is generally very cumbersome. As mentioned above, when the combination child seat is used with the integral harness system, i.e., in integral mode, the latter is commonly coupled to the headrest. In integral mode, known combination seats comprise an adjuster at the back of the seat for adjusting the headrest and the harness. For the transmission to the non-integral mode, many of the known combination child safety seats require the harness to be removed. Only if this is done, the headrest can be lifted further. The further raising of the headrest has to be done, however, by means of a second adjuster. Because of this, known child safety seats use two separate adjusters for adjusting the height of the headrest, depending on the integral or non-integral mode in which the seat is used. This not only makes the transmission cumbersome, but also implies a risk especially in cases where users need to refit the integral harness system, again.

It is, thus, an object of the present invention to provide a child safety seat with enhanced ease of use that allows for easier and faster transmission between integral mode and non-integral mode, and with an anti-misuse mechanism which prevents the usage of the non-integral mode too long and/or which prevents the usage of the non-integral mode too early.

This object is achieved by the child safety seat according to claim1and by the child safety seat according to claim10. Further advantageous embodiments of the present invention are indicated in claims2to9, and in claims11to15.

According to a first aspect of the invention there is provided a child safety seat comprising a seat shell, a headrest, a guiding component, which is slidably coupled to the seat shell, for guiding a strap of an integral harness system of the child safety seat, and an adjustment mechanism for adjusting the height of the headrest comprising a coupling element. The coupling element is configured to be placed in a first configuration and a second configuration. When placed in the first configuration, the coupling element couples the headrest with the guiding component such as to allow for movement of the headrest together with the guiding component relative to the seat shell. When placed in the second configuration, the coupling element couples the seat shell with the guiding component such as to prevent the guiding component from movement relative to the seat shell and such as to allow for movement of the headrest relative to the seat shell.

Owing to the two configurations the coupling element can be placed in, height adjustment of the child safety seat's headrest may be accomplished when used together with the integral harness system or with a safety belt of a vehicle for securing a child in the child safety seat. The child safety seat can be used in integral mode or in non-integral mode. There is no need for removing the integral harness system even when the child safety seat is used in the non-integral mode. The integral mode of the child safety seat is defined by the usage of the integral harness system for securing a child in the child safety seat. The non-integral mode is defined by the usage of the safety belt of a vehicle for securing the child in the child safety seat. The adjustment mechanism of the invention has the advantage that only the coupling element needs to be operated in order to disengage the guiding component for guiding the straps of the integral harness system from the headrest, when the headrest has reached a height corresponding to an age in which the non-integral mode becomes mandatory. Preferably, the first configuration is used during the integral mode. Preferably, the second configuration is used during the non-integral mode. Advantageously, the guiding component is a harness slider configured to guide the shoulder straps of the integral harness system. In the first configuration, due to the coupling of the headrest with the guiding component by the coupling element of the adjustment mechanism, the adjustment of the headrest causes the shoulder straps of the integral harness to be correctly positioned, and vice versa. When the coupling element is placed in the second configuration, the guiding component for guiding the shoulder straps of the integral harness system is decoupled from the headrest. The guiding component is prevented from movement relative to the seat shell, while movement of the headrest relative to the seat shell is possible. That is, when placed in the second configuration, the coupling element couples the seat shell with the guiding component such that the guiding component stays at a fixed position upon movement of the headrest. The fixation of the guiding component, when the coupling element is in the second configuration, allows the integral harness to remain fitted to the child safety seat. Because of the decoupling of the guiding component from the headrest, the movement of the headrest is not related to the guiding component any more. Therefore, the integral harness does not prevent the headrest from being adjusted in non-integral mode. Therefore, the height of the headrest may still be adjusted in the same way as in the first configuration. This has the advantage that only one element needs to be operated for height adjustment independent of the configuration in which the child safety seat is used. A second advantage is that the integral harness may stay on the child safety seat; it does not have to be removed when the child seat is used in the non-integral mode. Since the integral harness needs not to be removed, misuse by the user is prevented, especially when transmission is performed from the non-integral mode back to the integral mode.

Advantageously, the seat shell comprises a seating portion. The seating portion is configured to receive the bottom and part of the legs of the child.

Preferably, the child safety seat is configured such that the headrest is allowed to engage with the seat shell at heights ranging from a lowest position to an intermediate position, being further distant from the seating portion than the lowest position, when the coupling element is in the first configuration. It is further preferred that the child safety seat is configured such that the headrest is allowed to engage with the seat shell at heights ranging from the intermediate position to a highest position, being further distant from the seating portion than the intermediate position, when the coupling element is in the second configuration. The range between the lowest position and the intermediate position defines the adjustment range of the headrest in the first configuration. The lowest position defines the lowest possible position for the headrest. Preferably, this lowest position is chosen such that the headrest fits to children aged 1 year. The intermediate position defines the highest possible position of the headrest when the coupling element is in the first configuration, preferably, in integral mode. In other words, above the intermediate position the guiding component for the straps of the integral harness system is decoupled from the movement of the headrest. It is not possible to further raise the guiding component, e.g., with the outlets of the shoulder straps of the integral harness system, beyond the intermediate position. In addition, the headrest may not be placed at higher positions than the intermediate position as long as the coupling element is placed in the first configuration. This implies that for larger children sitting in the child safety seat it might not be possible to guide the straps of the integral harness system correctly over the shoulders of the child or to adjust the height of the headrest properly. Thus, a user trying to use the integral harness system for older children will recognize that this is hardly possible. Therefore, it is avoided that the child safety seat is used too long in integral mode.

It is advantageous if this intermediate position is chosen such that the headrest fits to children aged 4 years. The distance between the lowest position and the intermediate position is preferably between 9 cm and 13 cm, advantageously between 10.5 cm and 11.1 cm, the most preferred value being 11.1 cm.

The highest position defines the highest possible position of the headrest when the coupling element is in the second configuration, preferably, in non-integral mode. The highest position is preferably the highest possible position the headrest can be placed in. It is advantageous if this highest position is chosen such that the headrest fits to children aged 12 years. The distance between the intermediate position and the highest position is preferably between 12 cm and 16 cm, advantageously between 13.5 cm and 14.5 cm, the most preferred value being 14.2 cm.

The adjustment range may be taken from anthropometric data. In the integral mode, the shoulder height should be variable from 28 cm to 39.1 cm when measured from the seating portion. Since the guiding component is preferably positioned such that the shoulder straps of the integral harness are guided out of the guiding component substantially horizontally over the shoulders of the child, the guiding component is adapted to be moved in the range between 27 cm measured from the seating portion to 40 cm measured from the seating portion, advantageously between 28 cm measured from the seating portion to 39.5 cm measured from the seating portion. The lowest position is preferably positioned between 27 cm and 28 from the seating portion. The intermediate position is preferably positioned between 39 cm to 39.5 cm from the seating portion. In the non-integral mode, the shoulder height should be variable from 39.1 cm to 53.3 cm when measured from the seating portion.

Since the lower edge of the headrest is correctly positioned if it nearly touches the shoulders of the child sitting in the child seat, the headrest is adapted to be moved in the range between 27 cm measured from the seating portion to 55 cm measured from the seating portion, advantageously between 28 cm measured from the seating portion to 53.5 cm measured from the seating portion. The lowest position is preferably positioned between 27 cm and 28 from the seating portion. The highest position is preferably positioned between 53.0 cm to 53.5 cm from the seating portion.

Advantageously, the coupling element is configured such that a change from the first to the second configuration is possible only if the headrest is in the intermediate position. This means that a change from the first to the second configuration is only possible if the headrest is placed at the highest position possible in the first configuration. The advantage is that misuse is prevented and that it is prevented that large children are secured too long with the integral harness system. The user is, thus, forced to secure the child with the safety belt of the vehicle once the headrest needs to be adjusted at a height which is beyond the intermediate position.

Advantageously, in non-integral mode, the shoulder straps of the integral harness may be stowed or hidden behind a backrest cover of the child safety seat. The hiding of the shoulder straps behind the cover increases the comfort for the child sitting in the seat, when the latter is used in non-integral mode, since there is no direct contact of the child's back with the shoulder straps.

Advantageously, the coupling element, when placed in the first configuration, further couples the headrest with the guiding component such that the distance between the headrest and the guiding component remains constant upon their movement. Preferably, the distance is chosen such that the guiding component is positioned at a lower edge of the headrest. By this, the shoulder straps of the harness system are positioned such that they may substantially pass parallel over the shoulders of the child sitting in the child safety seat. This is the correct position of the shoulder straps. Since the distance does not change as long as the coupling element is in the first configuration, adjustment of the headrest causes the integral harness to be automatically adjusted, and vice versa. The adjustment of the integral harness is such that the guiding component and, thus, the shoulder straps guided through it, are at the correct height.

Advantageously, the adjustment mechanism further comprises a locking mechanism adapted to engage the headrest with the seat shell at different heights from the seating portion. The locking mechanism has the advantage to fix the headrest at different heights. This allows to adjust the headrest depending on the different sizes and ages of the child. Preferably, the locking mechanism is adapted to allow for a gradual displacement of the headrest. In an alternative, a continuous displacement of the headrest may, however, also be advantageous.

Advantageously, the locking mechanism of the adjustment mechanism further comprises an actuator operable to move the headrest from the lowest position to the intermediate position, when the coupling element is in the first configuration, and from the intermediate position to the highest position, when the coupling element is in the second configuration. The actuator which is operable to move the headrest both in the first configuration and in the second configuration has the advantage that the height adjustment of the headrest can be performed by one single operational element. The operation of the same actuator is sufficient to adjust the height of the headrest in the first configuration and in the second configuration of the coupling element. It is preferred that the actuator is situated on the top of the headrest. This allows adjustment of the headrest even when the seat is installed in a vehicle or even if the child is placed in the child safety seat.

Preferably, the locking mechanism comprises a toothed rack attached to the seat shell and a locking element, wherein the locking mechanism is configured such that the locking element is received by the toothed rack when the headrest is engaged with the seat shell. The toothed rack may either be integrally formed with the seat shell, or it may also be a separate component. The toothed rack and the locking element provide a simple mechanism allowing for a gradual displacement of the headrest. It is further preferable if the locking mechanism is configured such that the locking element disengages from the toothed rack upon operation of the actuator. This makes sure that the adjustment of the height of the headrest can be performed by operating only the actuator. That is, by operating the actuator the headrest is released from engagement with the toothed rack, allowing the headrest to be moved up or down the seat shell.

Advantageously, the seat shell further comprises a backrest portion, wherein the guiding component is slidable along the backrest portion, when the coupling element is placed in the first configuration. This, preferably, allows for adjustment of the integral harness system when the child safety seat is used in integral mode. Preferably, the backrest portion of the seat shell comprises a backrest opening, wherein the guiding component and the coupling element are slidably mounted in the backrest opening, when the coupling element is placed in the first configuration. The backrest opening advantageously provides for a guiding rail of the guiding component. It is further advantageous, if the backrest opening provides for a guiding rail of the coupling element, too. Preferably, the backrest opening of the seat shell is dimensioned so as to allow the headrest to move from the lowest position to the intermediate position.

Advantageously, the headrest has a headrest opening adapted to receive the guiding component, when the coupling element is in the second configuration, and wherein the headrest opening is dimensioned so as to allow the headrest to move from the intermediate position to the highest position. The headrest opening allows the headrest to be adjusted, once the coupling element is placed in the second configuration, even when the guiding component is fixed in the intermediate position.

Preferably, the coupling element is a transmission switch, a pivoted lever, or a sliding element. These are components which are cheap and easy to produce.

Advantageously, the child safety seat further comprises a compartment adapted to receive a locking member of the integral harness system, and a blocking element, wherein the blocking element is coupled to the headrest such that the blocking element blocks the compartment against reception of the locking member as long as the headrest is placed at heights lower than a lowest non-integral headrest position from the seating portion. The advantageous will be described and will become apparent with regard to the second aspect of the invention below.

According to a second aspect of the invention there is provided a child safety seat comprising a seat shell with a seating portion, a headrest, an integral harness system comprising a locking member, an adjustment mechanism for adjusting the height of the headrest, a compartment adapted to receive the locking member, and a blocking element. The blocking element is coupled to the headrest such that the blocking element blocks the compartment against reception of the locking member as long as the headrest is placed at heights lower than a lowest non-integral headrest position from the seating portion.

The lowest non-integral position defines the lowest position of the headrest at which the switch from integral mode to non-integral mode is allowed. Preferably, the lowest non-integral headrest position of the headrest corresponds to a child aged 3 years. Since the blocking element blocks the compartment against reception of the locking member as long as the headrest is placed at heights lower than the lowest non-integral headrest position it is avoided that the non-integral mode is used too early. A user trying to stow away the locking member of the integral harness system would notice that this is not possible. Therefore, the user will recognize that the child safety seat must be further used in integral mode. A locking member preferably comprises a buckle tongue of the integral harness system.

Advantageously, there will be no or not enough space available in the compartment for the locking members to be stowed away as long as the headrest is placed at heights lower than the lowest non-integral headrest position. It is also possible that the compartment is not accessible from the outside as long as the headrest is placed at heights lower than the lowest non-integral headrest position. Preferably, the compartment comprises a pocket for receiving the locking members.

Preferably, the coupling between the headrest and the blocking element is accomplished by a rigid connection. This ensures that any motion of the headrest is transferred to the blocking element.

Advantageously, the blocking element is further coupled to the headrest such that the blocking element blocks the headrest against placement at heights lower than the lowest non-integral headrest position from the seating portion as long as the locking member is received by the compartment. Preferably, the blocking of the headrest is caused by physical contact between the blocking element and the locking member received by the compartment. By this, it is, again, avoided that the child safety seat is used too early in non-integral mode. The child safety seat is used in non-integral mode when the child is secured in the child safety seat by use of a safety belt of a vehicle. Therefore, as long as the locking members of the integral harness system are stowed away in the compartment, the child safety seat cannot be used in integral mode. The situation in which the locking members are stowed in or received by the compartment typically occurs when a child safety seat upon use for older children in non-integral mode is transformed back to a child safety seat to be used for smaller children in integral mode. In said situation it might happen that a user uses the non-integral mode for children that are not yet amenable to it. Such a situation does, however, not occur in accordance with the invention, since the user is not able to bring the headrest to a lower position than the lowest non-integral headrest position. The user trying to use non-integral mode for smaller children will, thus, recognize that he will have to switch to integral mode in order to adjust the headrest properly.

Advantageously, the blocking element is further configured to reduce the space available in the compartment such that the locking member does not fit into the compartment as long as the headrest is placed at heights lower than the lowest non-integral headrest position. This is a simple way to ensure that the locking members are not stowed away until the headrest has been placed at least at the lowest possible non-integral headrest position. In addition, since there is not enough room for the locking members to be received by the compartment as long as the headrest is placed lower than the non-integral headrest position, it follows that the headrest may not be lowered to a lower than the lowest non-integral headrest position as long as the locking members are stowed in the compartment. The locking members would physically block the blocking element trying to further reduce the space of the compartment. Preferably, the blocking element is coupled to the headrest such that the blocking of the blocking element causes the blocking of the headrest.

Advantageously, the coupling between the blocking element and the headrest is further such that the locking member can be received by the compartment when the headrest is placed at a height higher than the lowest non-integral headrest position. This allows to switch to non-integral mode when the lowest allowed height of the headrest for doing so is reached.

Preferably, the seat shell further comprises a backrest portion, and the compartment is integrated in the backrest portion. A compartment integrated in the backrest portion of the child safety seat has the advantage of easy reachability. A further advantage is that when switching from integral to non-integral mode it is not necessary to remove the entire integral harness system. Preferably, the integral harness system may be stowed beneath a cover of the backrest portion. The locking members are stowed in the compartment.

It is understood, that a child safety seat in accordance of the first aspect of the invention may be combined with any feature of the second aspect of the invention, and vice versa. In fact, it is particularly advantageous if the anti-misuse mechanism of the first aspect and the anti-misuse mechanism of the second aspect are integrated in one single child safety seat. This provides maximal protection against too early switching from integral to non-integral mode and against using the integral mode too long.

Advantageously, the child safety seat is a combination child safety seat configured to be used with the integral harness system or with a safety belt of a vehicle.

InFIG. 1aa child safety seat100in accordance with the invention is shown. The child safety seat100comprises a seat shell1and a headrest2. The seat shell1is for receiving a child. The seat shell1is covered by a cover. The cover is padded. The seat shell1comprises a backrest portion11for receiving, in particular, the back of the child. The seat shell1further comprises a seating portion12for receiving, in particular, the bottom of the child and parts of his or her legs. The headrest2is shown in its lowest position. That is, the distance between the headrest2and the seating portion12of the seat shell1is minimal. This position is suited for small children with an age of about 1 year. The headrest2has a central region21for receiving the head of the child. Furthermore, the headrest2comprises two lateral portions22. These lateral portions22have the form of side wings. They may be padded. The lateral portions22surround the child's head and provide protection, in particular, in the case of a side impact. The child safety seat100further comprises an integral harness system5. Of the integral harness system5there are shown the shoulder straps51, the lap straps52and the harness buckle53with buckle tongues. The integral harness system5shown inFIG. 1ais a 5-point harness system. The shoulder straps51are guided through a guiding component3from the back side (not visible) of the seat shell1to the front side of the seat shell1.

InFIG. 1athe child safety seat is shown in the so-called integral mode, this is, the child safety seat100is used with the integral harness system5. In the integral mode, the guiding component3and the headrest2are coupled to one another. The coupling is achieved through the adjusting mechanism with coupling element which will be described in detail below. By means of this coupling, the movement of the headrest2causes a respective movement of the guiding component3. For this, the guiding component3is slidable along the seat shell1. Because of this, the guiding component3may be designed as a harness slider. Preferably, the harness slider is configured to slide along the backrest portion11of the seat shell1and to adjust the height of the integral harness5.

FIG. 1bshows the child safety seat100ofFIG. 1astill in integral mode. InFIG. 1bthe headrest2has been moved to the highest position possible in integral mode. In the following, this position will be referred to as “intermediate position”, in order to distinguish this position from highest possible position in non-integral mode. The latter being the highest possible position of the headrest which can be achieved within the child safety seat100.

The adjustment of the height in integral mode can be accomplished by operating an actuator8. The actuator8shown inFIG. 1bcomprises a handle81. The handle81is integrated on the top of the headrest2. As long as the actuator8is operated, the headrest may be adjusted at a height between the lowest position and the intermediate position. The details of the height adjustment mechanism will be described below with respect toFIGS. 4 to 7.

When comparingFIG. 1aandFIG. 1b, then the coupling of the headrest2and the guiding component3in integral mode becomes evident. The distance between the headrest2and the guiding component3remains constant. This ensures that the shoulder straps51of the integral harness are guided substantially horizontally from the guiding component3over the shoulders of the occupant of the child safety seat. This is the optimal pathway of the shoulder straps51in order to guarantee the most efficient restraint of the child in the case of a frontal collision. The lower edge23of the headrest2lies slightly above the guiding component's3outlets for the shoulder straps51. For adjusting the height of the headrest2it is, therefore, sufficient to bring the lower edge23of the headrest2into the correct position above the shoulders of the occupant of the child safety seat. Owing to the coupling of the guiding component3and the headrest2a misuse or a misplacement of the shoulder straps51is, therefore, highly reduced.

FIG. 2shows the child safety seat100ofFIGS. 1aand 1bin non-integral mode. This means that a safety belt500of a vehicle is used to secure a child in the child safety seat100. The integral harness is not shown any more. According to the invention, it is, however, not necessary to remove the integral harness when the child safety seat100is used in non-integral mode. Preferably, the integral harness is, at least partially, covered by the cover of the seat shell or the backrest portion of the seat shell. When comparingFIG. 2toFIG. 1bit is manifest that the guiding component3has not moved, that is, it is fixed at the height it had when the headrest was positioned in the intermediate position. The height of the headrest2has increased. This is possible, because, according to the invention, in non-integral mode, the coupling between guiding component3and headrest2is released. The adjustment of the height of the headrest2in non-integral mode can be accomplished by operating the actuator8. Preferably, the actuator8comprises a handle81positioned on the top of the headrest2. The details of the height adjustment mechanism in non-integral mode will be described below with regard toFIGS. 5band6.

The height adjustment of the headrest2can be performed both in non-integral mode and in integral mode by operating the same actuator8.

The child safety seat100described with regard toFIGS. 1a, 1band2is a so-called combination child safety seat. Such a combination child safety seat may be used for children with an age between approximately 1 year and 12 years. This is possible because of its transformability from a child safety seat with integral harness to a child safety seat which can be used with the safety belt of a vehicle, as described above.

FIG. 3is an exploded view of the child safety seat100of the invention. Shown is the seat shell1, with cover and padding removed. The seat shell1comprises a backrest portion11and a seating portion12. In the backrest portion11two openings6are visible. Furthermore, a toothed rack9is integrated in the seat shell1. The toothed rack9is shown to be attached to the backrest portion11of the seat shell1. The toothed rack9of the shown embodiment is integrally formed with the seat shell1; it may, however, also be formed as a separate part.FIG. 3further shows a headrest2(with cover and padding removed). The headrest2comprises two openings7. The guiding component3for guiding the shoulder straps of the integral harness system is also shown. In addition, the coupling element4is depicted. A bar34connecting the guiding component3and the coupling element4is also shown. Further, the actuator8is shown. The actuator8comprises a handle81, a transmission element82, and an elastic component83, such as a spring, and a locking element84, such as a locking bar. The toothed rack9and the actuator8are comprised by the invention's locking mechanism. The coupling element4and the locking mechanism are part of the height adjustment mechanism of the invention. The locking mechanism will be described in detail below with regard toFIG. 7.

The openings6in the backrest portion11provide for a guiding rail of the guiding component3and the coupling element4when the child safety seat is used in integral mode. The purpose and functioning of the backrest openings6will become apparent below in the description ofFIGS. 4aand4b.

The openings7of the headrest are adapted to receive the guiding component, when the child safety seat100is used in the non-integral mode. The openings7in the headrest allow the headrest2to be adjusted in non-integral mode, even though the guiding component3is fixed in the intermediate position. The further purpose and functioning of the headrest openings7will become apparent below in the description ofFIGS. 5band6.

FIGS. 4a, 4b, 5a, 5b, and6show in sequence the adjustment of the headrest from the lowest position to the highest position. Specifically, inFIGS. 5aand 5bthe transmission of the coupling element4from the first configuration to the second configuration is depicted.

InFIG. 4athere are shown a headrest2with an opening7, a guiding component3, and a coupling element4. The coupling element4is part of the height adjustment mechanism. Furthermore, a shoulder strap51of the integral harness system is shown. The shoulder strap51is guided through the guiding component3. In addition a part of the backrest portion11of the seat shell with a respective opening6is visible. The headrest2is coupled to the guiding component3by the coupling element4. The headrest2comprises a recess24. The recess24is adapted to receive a corresponding engaging member41of the coupling element4. According to the embodiment shown inFIG. 4athe guiding component3and the coupling element4are connected to one another by means of a bar34. Other coupling means are possible. The coupling element4shown inFIG. 4ais designed as a transmission switch. This transmission switch4is pivotably mounted about the bar34. The seat shell may comprise guiding means, such as rails or a recess (not shown), adapted to receive the ends of the bar34. If present, said guiding means need, further, be adapted to allow for movement, e.g., sliding, of the bar34along the backrest portion11of the seat shell. InFIG. 4athe coupling element4is placed in the first configuration. In this first configuration, the coupling element4connects the headrest2with the guiding component3. The three components coupling element4, headrest2and guiding component3form a compound. This compound can be moved along the opening6of the backrest portion11of the seat shell. InFIG. 4a, the headrest2is placed in the lowest possible position.

FIG. 4bshows the change of the position of the headrest2, the guiding component3and the coupling element4in relation toFIG. 4a, after adjustment of the height of the headrest2. The height adjustment during integral mode may be achieved be operating an actuator and pulling the headrest2upwards in relation to the seat shell, as indicted by the arrow A. As long as the actuator is operated, the headrest2is released from engagement with the seat shell. The details of said operation will be described in more detail below in relation toFIG. 7. The configuration of the coupling element4has not changed. The coupling element4is still in the first configuration. That means that the headrest2and the guiding component3are still coupled to one another by the coupling element4in the same way as described above in relation toFIG. 4a. In order for the headrest2to arrive at the position shown inFIG. 4b, the guiding component3and the coupling element4are travelling, at least partially, along the openings6of the backrest portion11. The backrest openings6serve as guiding rails for stabilizing the components headrest2, guiding component3and coupling element4against side movement. InFIG. 4bthe guiding component3has reached the upper end of the opening6of the backrest portion11. Therefore, it has reached the stop. It is not possible to further increase the height of the headrest2as long as the coupling element4is in its first configuration. Owing to the coupling of the headrest2and the guiding component3, the distance between the guiding component3, in particular that of the shoulder strap outlets of the guiding component3, and the headrest2remains constant. The coupling element4placed in the first configuration corresponds, thus, to the child safety seat being used in the integral mode. Together with the movement of the guiding component3, a shoulder strap51which is guided through the guiding component3, is travelling along the backrest portion11of the seat shell. This allows to adjust the height of the integral harness system. A locking mechanism which is adapted to engage the headrest2to the seat shell, preferably to the backrest portion11of the seat, will be described in detail with respect toFIG. 7.

FIGS. 5aand 5bshow the transmission of the coupling element4from the first configuration to the second configuration when the headrest2has reached the intermediate position, that is, the highest possible position in integral mode.

InFIG. 5a, the coupling element4of the child safety seat is in the first configuration. The configuration of the child safety seat shown inFIG. 5acorresponds to that depicted inFIG. 4b. The coupling element4, thus, couples the guiding element3and the headrest2. The coupling might be achieved by an end portion41of the coupling element4being received by a recess24of the headrest2, as described above in relation toFIG. 4a.

FIG. 5bshows the child safety seat with the coupling element4of the adjustment mechanism placed in the second configuration. The headrest2is still positioned in the intermediate position, that is, at the same height as shown inFIG. 5a. The guiding component3is shown to abut against the upper end of the opening7of the headrest. The guiding component3abuts against the upper end of the opening6of the backrest portion11of the seat shell. Compared toFIG. 5a, inFIG. 5bthe coupling component4has been pivoted or rotated about the bar34. The pivoting/rotation is indicated by arrow B. The coupling element4is not received by the recess24of the headrest2anymore. The coupling element4remains, however, engaged with the guiding component3. In the embodiment shown inFIG. 5b, the latter engagement is achieved through the bar34. When in the second configuration, as shown inFIG. 5b, the coupling element4of the adjustment mechanism does not couple the guiding component3to the headrest2any longer. That is, the headrest2is free to move without connection to the guiding component3. Furthermore, as manifest inFIG. 5b, a respective engaging member42of the coupling element4is received in recess25of the backrest portion11of the seat shell. By this, the coupling element4couples the guiding component4with the backrest portion11of the seat shell. The guiding component4is, therefore, prevented from further movement. In other words, the height of the headrest2may be adjusted while the guiding component4stays fixed. The guiding component3cannot be placed at a higher position from the seating portion of the seat shell than the intermediate position. This prevents a user from using the child safety seat with the integral harness system, i.e., in integral mode, for children which have already grown out of integral mode seats.

In a preferred embodiment, the transmission of the coupling element4between the first configuration, as shown, e.g., inFIG. 5a, and the second configuration, as shown, e.g., inFIG. 5b, is only possible if the headrest2is positioned in the intermediate position. This may be achieved by properly choosing the dimensions of the recess24of the headrest2, the recess25of the backrest portion11, and those of the corresponding engaging members41and42of the guiding component4. InFIG. 5bthe headrest2is in the intermediate position. In this case, when a user pivots/rotates the guiding component4about the bar34, the recess25in the backrest portion11is positioned such that it is able to receive the corresponding engaging member42of the coupling element4. Assuming that the headrest2were at a height lower than the intermediate position, then, when a user tried to pivot/rotate the guiding component4about the bar34, the engaging member42of the guiding component4would abut against a part of the backrest portion11preventing the engaging member41of the guiding component4from fully disengaging from the recess24of the headrest2. Therefore, the coupling between the headrest2and the guiding component3remains intact unless the headrest2has reached the intermediate position. An analogous consideration holds true for the transmission from the second configuration of the coupling element4to the first configuration.

FIG. 6shows the change of the position of the headrest2, the guiding component3and the coupling element4in relation toFIG. 5b, after adjustment of the height of the headrest2. The height adjustment when the coupling element4is in the second configuration, such as in non-integral mode, may be achieved in the same way as when the coupling element4is in the first configuration, e.g., in integral mode. That is, height adjustment may be done by operating the same actuator as in integral mode and pulling the headrest2upwards in relation to the seat shell, as indicated by the arrow C. As long as the actuator is operated, the headrest2is released from engagement with the seat shell. The details of said operation will be described in more detail below in relation toFIG. 7. The configuration of the coupling element4has not changed with regard to that ofFIG. 5b. This means that, as described in detail above with regard toFIG. 5b, the coupling element4couples the guiding component3with the backrest portion11of the seat shell; the headrest2is not connected to the guiding component3anymore. In order for the headrest2to arrive at the position shown inFIG. 6, the headrest2is travelling, at least partially, along the backrest portion11of the seat shell. The headrest2comprises one or more openings7. The headrest openings7ensure that the guiding component3does not prevent the headrest2from movement in the non-integral mode. In other words, when seen from the headrest's2frame of reference, the guiding component3travels along the headrest openings7from the upper stop of the headrest openings7towards the lower stop of the headrest openings7when the height of the headrest2is increased, as indicted by arrow C, in non-integral mode. With respect to the backrest portion11of the seat shell, the guiding component4remains at a fixed position, preferably the intermediate position, while the headrest2moves upwards with respect to the backrest portion11, thereby increasing the height of the headrest2. The headrest openings7cooperating with the guiding component4as described previously contribute, in addition, to a stabilization of the headrest2against lateral movement.

InFIG. 6the headrest2has reached the highest possible position, i.e., the highest position. The lower end of the opening7of the headrest2abuts against the guiding component3. Therefore, it has reached the stop. It is not possible to further increase the height of the headrest2. Since the coupling element4does not couple the guiding component3with the headrest2, upon height adjustment of the headrest2, a shoulder strap51which is guided through the guiding component3, remains at a fixed position of the backrest portion11of the seat shell. The integral harness system does not need to be removed from the child safety seat. The height adjustment of the headrest2may be performed in non-integral mode despite the installed integral harness system. For comfort's reasons, it is possible to stow the shoulder straps51of the integral harness behind the cover of the child safety seat. It is, however, also possible to remove the integral harness system from the child safety seat, for the purpose of e. g. cleaning, maintenance, exchange etc. A locking mechanism which is adapted to engage the headrest2to the seat shell, preferably to the backrest portion11of the seat, will be described in detail with respect toFIG. 7.

FIG. 7shows a locking mechanism which may be used for bringing the headrest2into engagement with the seat shell, preferably with the backrest portion11of the seat shell, at different heights. InFIG. 7a configuration is shown in which the headrest2is in engagement with the backrest portion11of the seat shell. That is, the headrest2is fixed at a certain height to the seat shell. The locking mechanism is part of the height adjustment mechanism of the child safety seat. The locking mechanism comprises a toothed rack9and an actuator8. The actuator8comprises a handle (not shown inFIG. 7, but shown with reference numeral81inFIG. 3), a transmission element82, and an elastic component83, such as a spring, and a locking element84, such as a locking bar. The actuator8is coupled to the headrest2of the child safety seat. The toothed rack9is integrated into the seat shell, preferably, into the backrest portion11of the seat shell. The toothed rack9comprises notches91configured to receive the locking bar84. The notches are spaced apart in such a manner that the headrest2is adjustable at a given number of different heights. By means of the toothed rack9, a gradual height adjustment of the headrest2is possible. The toothed rack9may be integrally formed with the seat shell. It is, however, also possible that the toothed rack9is separately formed and afterwards integrated into the seat shell.

The locking mechanism is locked by locking the locking bar84between the transmission element82and the toothed rack9. In this way, the locking bar84cannot be removed from the notch91of the toothed rack9it is placed in. The transmission element82transfers the movement of the handle into movement of the locking bar84. The locking bar84is slidably mounted in one or more recesses26of the headrest2. This may be achieved, e.g., by the end portions of the locking bar84being received in corresponding recesses26. By this, the locking bar84is connected to the headrest2. Upon operation, e.g., by pulling, of the handle, the transmission element82is moved in the same direction. The movement of the transmission element82is against the force of the elastic component83. When the handle is pulled upwards, the transmission element82first compresses the elastic element83. Once a certain threshold or a stop is reached, the elastic element83does not compress any longer. In this position of the transmission element82the receiving portion85of the transmission element82is aligned with the notch91of the toothed rack9the locking bar84is placed in, so that the locking bar84is free to move into the receiving portion85.

If the handle is, then, further pulled, the headrest2to which the actuator8is coupled, is pulled upwards. By pulling upwards the headrest2, the recesses26for the locking bar84integrated in the headrest2are also moved upwards. This causes the locking bar84to move out of a notch91of the toothed rack9into the receiving portion85. The movement of the locking bar84in relation to the headrest2is restricted by the recesses26. Once the locking bar84has moved out of a notch91of the toothed rack9, the headrest2is released from engagement with the seat shell. The height of the headrest2is then adjustable. The headrest2may be moved up or down the backrest portion11of the seat shell. Once the appropriate height has been found the user stops operating the actuator8. Then, the elastic element83drives the transmission element82back to its rest position. On its way back to the rest position, the transmission element82drives the locking bar84into engagement with the toothed rack9. The locking bar84may be driven by the transmission element82along the recesses26into one of the notches91of the toothed rack9. The headrest2is, then, fixed at certain height with respect to the seat shell, in particular, with respect to the backrest portion11or the seating portion of the seat shell.

According to the child safety seat of the invention, one actuator8is sufficient for adjusting the height of the headrest2both in integral mode and in non-integral mode. This implies that the same locking mechanism is suitable for both modes. The locking mechanism described with respect toFIG. 7may be used when the coupling element of the adjustment mechanism is in the first configuration, as well as when the coupling element is in the second configuration. This means that the toothed rack9is preferably chosen such that it allows for height adjustment of the headrest2from the lowest position, i.e., the lowest possible position, i.e., the lowest possible position in integral mode, up to the highest position, i.e., the highest possible position, i.e., the highest possible position in non-integral mode.

The anti-misuse mechanism of the embodiments described before prevent the usage of the integral mode too long. They do, however, not necessarily prevent a user of the child safety seat from using the non-integral mode too early. As described above, it is one advantage of the invention that the integral harness system does not necessarily need to be removed when switching from integral to non-integral mode. Therefore, the user is not prevented from changing to non-integral mode even if the headrest has not yet reached the intermediate position.

The embodiments described in the following with respect toFIGS. 8a, 8b, and8cprovide an anti-misuse mechanism against too early usage of the non-integral mode. The anti-misuse mechanism for preventing the non-integral mode too early may be used in addition to the anti-misuse mechanism for preventing usage of the integral mode too long in the same child safety seat. When both anti-misuse mechanisms are jointly used in the same embodiment of a child safety seat, enhanced/optimal anti-misuse protection is provided.

FIG. 8ashows a child safety seat with an anti-misuse mechanism preventing too early usage of the non-integral mode. InFIG. 8athere is shown a seat shell1of the child safety seat, comprising a backrest portion11and a seating portion12, a headrest2, and a guiding component3for guiding the shoulder straps51of the integral harness system5. The guiding component3is preferably a harness slider. In addition to the shoulder straps51, a locking member54of the integral harness system5is shown. Preferably, the locking member54is a buckle tongue adapted to be secured in a harness buckle (not shown) of the integral harness system5. Moreover, it is shown that a blocking element27is coupled to the headrest2. The backrest portion11of the child safety seat comprises a front part111and a rear part112. The front part111is the part of the backrest portion12adapted to receive the back of a child which is placed in the child safety seat. The rear part112of the backrest portion12is the part turned away from the child. The front part111of the backrest portion12comprises an opening551. The opening551is dimensioned such that the locking member54fits through it. Between the front part111and the rear part112of the backrest portion12there is located a compartment55. The dimensions of the compartment55are such that it is adapted to receive the locking member54, or, if more than one locking member54is employed, to receive all of the locking members54. The compartment54may comprise one or more pockets. The shown child safety seat is used in integral mode. That is, the integral harness system5is used to secure a child placed in the child safety seat. In this case the blocking element27blocks the compartment against reception of the locking member54. As shown inFIG. 8a, the blocking element27blocks the opening551of the front part111of the backrest portion12. It is not possible to bring the locking member54through the opening551into the compartment55. The blocking element27not only blocks the opening551, and, thus the entrance to the compartment55. The shown blocking element27is also dimensioned such that it reduces the space available in the compartment55so that the locking member54would not fit into it. The blocking element27is coupled to the headrest2. The blocking element27may be integrally formed with the headrest2. It is, however, also possible that the blocking element27is a separate part which is coupled, e.g., attached, to the headrest.

In addition, it is advantageous that the child safety seat shown inFIG. 8acomprises an adjustment mechanism comprising a coupling element (not shown) configured to be placed in a first and a second configuration for coupling the guiding component3with the headrest2or the seat shell1, respectively, as described in detail above, in particular, with respect toFIGS. 3 to 6. In this case, the child safety seat comprises, in addition to the anti-misuse mechanism preventing too early usage of the non-integral mode, an anti-misuse mechanism preventing too long usage of the integral mode.

In the shown integral mode, it is not possible for a user to stow away the locking member54in the compartment55. Therefore, by choosing the dimensions of the compartment55and the blocking element27so that it is possible to stow the locking member54in the compartment55only once the headrest2has reached a lowest non-integral headrest position, it is avoided that the non-integral mode is used too early.

FIG. 8bshows the child safety seat ofFIG. 8awith the headrest2raised to a higher position with respect to the seating portion12. The headrest2is placed at the lowest non-integral headrest position. This position is defined as the minimal possible height of the headrest2(with respect to the seating portion12) for which it is possible to store the locking member54in the compartment55. In the shown embodiment the blocking element27is coupled such to the headrest2that the raising of the headrest2above the lowest non-integral headrest position causes the blocking element27to release the compartment55from being blocked. For this, the blocking element27may be rigidly connected to the headrest2. The blocking element27may be integrally formed with the headrest2. In the shown embodiment, the lower edge of the blocking element27is at the same height as the upper edge of the opening551. Assuming that the opening551is dimensioned such that the locking member54fits through it, then the lowest non-integral headrest position of the shown embodiment is reached when the blocking element27fully clears/unblocks the opening551. Only starting from heights of the headrest being equal to or exceeding the lowest non-integral headrest position is it possible for a user to store/stow away the locking member54or locking members54in the compartment55. As long as the headrest2is placed at heights lower than the lowest non-integral headrest position, the blocking element27blocks the compartment55. As long as this is the case, the storage of the locking members54in the compartment55is not possible.

InFIG. 8b, the locking member54is not yet stored in the compartment55. The child safety seat is, thus, in integral mode. It is, however, possible to store the locking member54in the compartment55, since the opening551is clear/unblocked. In other words, the child safety seat could be switched from integral mode to non-integral mode. This may be accomplished by storing the locking member54in the compartment55.

FIG. 8cshows the child safety seat ofFIG. 8b, that is, with the headrest2placed at the lowest non-integral headrest position. InFIG. 8c, the locking member54is stored in the compartment55. The transmission from the integral mode of the child safety seat to the non-integral mode has been performed. In the non-integral mode, the child needs to be secured in the child safety seat by means of the safety belt of the vehicle. When further raising the headrest2, the blocking element27raises, too. On the other hand, when lowering the headrest2in non-integral mode with the locking member54stored in the compartment55, the following situation might occur. When the blocking element27is rigidly connected to the headrest2then the blocking element27will be lowered upon lowering of the headrest2. If a user tries to lower the headrest2beneath the lowest non-integral headrest position, the blocking element27will, thus, get in contact with the locking member54. The locking member54, thus, physically blocks the blocking element27against upward movement. The blocking of the blocking element27causes the blocking of the headrest2. Because of this, as long as the locking member54is stored in the compartment55, it is not possible for the headrest2to be lowered to heights substantially lower than the lowest non-integral headrest position. This prevents a user from switching back from non-integral mode to integral mode for children which are too small.

As described above, it is advantageous that the child safety seat shown inFIGS. 8a, 8b, and 8ccomprises an adjustment mechanism comprising a coupling element configured to be placed in a first and a second configuration for coupling the guiding component3with the headrest2or the seat shell1, respectively, as described, in particular, with respect toFIGS. 3 to 6. In this case, the lowest non-integral headrest position is at a position less distant from the seating portion12than the intermediate position at which the change from the first configuration of the coupling element to the second configuration is possible. The intermediate position defines the highest possible position of the headrest2in integral mode. The lowest non-integral headrest position defines the lowest possible position of the headrest2in non-integral mode. Preferably, the intermediate position corresponds to children aged 4 years. Preferably, the lowest non-integral headrest position corresponds to children aged 3 years. Between the lowest non-integral headrest position and the intermediate position the child safety seat may be used both in integral and non-integral mode.

LIST OF REFERENCE NUMERALS

1seat shell11backrest portion of the seat shell1111front part of the backrest portion11112rear part of the backrest portion1112seating portion of the seat shell1100child safety seat2headrest21central region of the headrest222lateral portion of the headrest223lower edge of the headrest224recess of the headrest225recess of the backrest portion1126recess(es) of the headrest2for receiving the locking element/locking bar84of the actuator827blocking element3guiding component34bar connecting guiding component3and coupling element44coupling element41engaging member of the coupling element4corresponding to the recess24of the headrest242engaging member of the coupling element4corresponding to the recess25of the backrest portion115integral harness system51shoulder straps of the integral harness system552lap straps of the integral harness system553harness buckle of the integral harness system554locking member/buckle tongues of the integral harness system555compartment for the locking member54551opening of the compartment55500safety belt of a vehicle6opening(s) of the backrest portion11/backrest opening(s)7opening(s) of the headrest2/headrest opening(s)8actuator81handle of the actuator882transmission element of the actuator883elastic component of the actuator884locking element/locking bar of the actuator885receiving portion for locking bar849toothed rack91notch(es) of the toothed rack9A arrow indicating movement of the headrest2in integral modeB arrow indicating the pivoting/rotation direction of the coupling element4C arrow indicating movement of the headrest2in non-integral mode