[0001] The invention relates to a child proof lid for a container, said lid comprising a
lid frame, firmly mountable on the container and a detachable and supported lid disc
mounted in the lid frame, said lid disc having two substantially parallel and opposing
lateral edges and opposite end portions extending under projecting portions of the
frame.
[0002] German Offenlegungsschrift No. 36 43 603 discloses a lid frame of the above type
in which the lid disc is supported by a circumferential abutment surface extending
from the inner periphery of the lid frame. One of the projecting portions comprises
a hinged tongue, said tongue having a downwards facing knob which engages an opening
in the lid disc. When the hinged tongue is turned upwards so as to disengage the knob
from the opening in the lid disc, the lid disc, having been displaced in its plane,
can be removed from the frame. Persons with weak fingers, e.g. caused by arthritis,
may find it difficult to turn the hinged tongue upwards and thereby to remove the
lid disc.
[0003] The object of the invention is to provide a lid of the above type which is inexpensive
to manufacture, is mountable on a container without necessitating changes in the normal
production line of the container and which can be opened without problems also by
people with weak fingers.
[0004] The lid according to the invention is characterised in that the projecting portions
of the frame are firm, that there is provided a stop means to prevent displacement
of the lid disc in relation to the lid frame in the plane of the disc, that the lid
disc is elastically bendable and supported by a protrusion projecting under the parallel
lateral edges of the lid disc at a distance from the end portions of the lid disc
and that there is a cavity in the lid frame under the end portions of the lid disc,
said cavity at least at the one end portion extending a distance beyond the end portion
corresponding to at least the distance the opposite end portion extends under the
superjacent frame portion. In order to remove the lid disc from the lid frame, the
lid disc must be pressed downwards close to at least one of its end portions, thereby
attaining a curvature whereby the stop means is rendered ineffective. Subsequently,
while still being pressed downwards and being curved said lid disc is slid into the
cavity extending beyond the adjacent discend portion. The opposite end portion will
thereby clear the adjacent projecting end portion and the lid disc can be removed
from the frame. Children in the dangerous age will normally not be able to copy such
motion pattern and therefore the lid will prevent such children from gaining access
to the contents of the container on which the lid is mounted. At the same time the
lid has the advantage that it does not require any special finger strength to press
and slide the lid disc in order to remove it from the frame and therefore the lid
disc can also be removed by persons with arthritic fingers.
[0005] According to the invention, the stop means may comprise a boss projecting from each
of the end portions of the lid disc, said boss engaging an opening in the adjacent
projecting frame portion. As a result, both end portions of the lid disc must be pressed
downwards at the same time and the lid disc subsequently be displaced in order to
remove the lid disc from the frame. Such motion pattern provides optimum safety that
children will not be able to open the lid, without at the same time making it difficult
for grown-up persons to remove the disc from the frame.
[0006] Moreover, according to the invention the stop means may comprise a boss projecting
at the one end portion of the lid disc, said boss engaging an opening in the adjacent
projecting frame portion and an edge of each end portion abutting a corresponding
abutment surface on the interior of the frame. According to this embodiment both end
portions of the lid disc should also be pressed downwards at the same time in order
to render possible a displacement and thereby the removal of the lid disc.
[0007] Further according to the above embodiment, the end portion not provided with a boss
can only just extend under the superjacent projecting frame portion. As a result,
the lid disc can be mounted in the lid frame by first sliding the lid end portion
provided with a boss under the corresponding projecting frame portion provided with
an opening and subsequently, by snap action, moving the other end portion of the lid
disc past the other projecting frame portion to abut it. Although the lid disc is
easily and quicly mounted in the frame, it is necessary in order to remove the lid
disc to press said lid disc downwards at both ends and subsequently to slide it in
relation to the frame.
[0008] Moreover, according to the invention, the supporting protrusions may be longitudinal
strips with a substantially plane supporting surface, said supporting surface gradually
changing into downwards sloping surfaces at each end. As a result, the supporting
surface provides excellent support for the disc and prevents a downwards deflection
of the lid disc in the middle while the downwards sloping surfaces limit the deflection
of the ends of the lid disc when pressed downwards.
[0009] Finally, according to the invention, the supporting protrusions are situated at a
distance under the projecting portions substantially corresponding to the thickness
of the disc.
[0010] The invention is described in greater detail below with reference to the accompanying
drawings in which
Figure 1 is a plan view of a lid frame belonging to a lid acccording to the invention,
Figure 2 is a sectional view of the lid frame taken along the line II-II of Figure
1,
Figure 3 is a sectional view of the lid frame taken along the line III-III of Figure
1,
Figure 4 is a sectional view of the lid frame taken along the line IV-IV of Figure
1,
Figure 5 is a plan view, a rear view and a side view, respectively of a lid disc adapted
for the lid frame shown in Figures 1 to 4 above,
Figure 6 is the lid disc shown in Figure 5 mounted in the lid frame shown in Figures
1 to 4 above, and
Figure 7 is another embodiment of a lid according to the invention, comprising a lid
frame and a lid disc mounted therein.
[0011] Figures 1 to 4 show a lid frame 1 of a first embodiment of a lid according to the
invention. In a plan view, the lid frame 1, which is made of plastics such as polypropylen
of polyethylene, is substantially rectangular and comprises two substantially parallel
frame side portions 2, 3 and two substantially parallel frame end portions 4, 5. Adjacent
the bottom of the frame 6 ,a longitudinal strip 7, 8 extends from the interior side
9, 10 of each of the frame side portions 2, 3. Each longitudinal strip 7, 8 has a
plane upper supporting surface 11, 12, said upper supporting surface gradually changing
into a downwards sloping surface 13, 14, 15, 16 at each end.
[0012] A first rib 17 extends inwards from the inner surface 18 of the frame end portion
situated to the right in Figure 1 at the upper end of the frame end portion 5. Viewed
from the side, the lower surface 19 of the rib 17 is spaced from the supporting surfaces
11, 12, and is parallel to these. An opening 20 is provided in the rib 17 adjacent
the inner surface 18 of the frame end portion 5.
[0013] Another rib 21 extends from the inner surface 22 of the frame end portion 4 situated
to the left in Figure 1 at its upper end. The rib 21 extends parallel to the supporting
surfaces 11, 12 and has a lower surface 37, said lower surface flushing with the lower
surface 19 of the first rib 17. Furthermore, the other rib 21 has a protrusion 23
on its lower surface 37, said protrusion forming an abutment edge 24 immediately inside
the edge 25 of the rib.
[0014] Figure 5 shows a lid disc 26 mountable in the lid frame 1 of Figures 1 to 4. The
lid disc 26 is of plastics, such as polypropylen or polyethylene and has opposite
parallel lateral edges 27, 28 and opposite substantially parallel end edges 29, 30,
the end edge shown to the right in Figure 5 however being slightly curved corresponding
to the curvature of the inner surface of the frame end portion of the frame situated
to the right in figure 1. At the slightly curved end edge 29 a boss 31 extends upwards
from the upper surface of the lid disc. The boss 31 is adapted to engage the opening
20 of the rib 17. The lateral edges 27, 28 of the lid disc are placed at a mutual
distance corresponding to the distance between the interior sides 9, 10 of the frame
side portions 2, 3, while the distance between the end edges 29, 30 of the lid disc
corresponds to the distance between the abutment edge 24 of the rib 21 and the inner
surface 18 of the frame end portion 5. Furthermore, the lid disc 26 has a thickness
substantially corresponding to the distance between the supporting surfaces 11 and
12 of the longitudinal strips 7, 8 and the lower surface of the ribs 17, 21.
[0015] When mounted in the frame 1 (cf. figure 6), the lid disc 26 is supported by the longitudinal
strips 7, 8 in the middle portion and along its lateral edges, and its end portions
33, 34 extend under the projecting ribs 17, 21 and abut the underside of said ribs.
At the same time the curved end edge 29 of the lid disc abuts the inner surface 18
of the frame end portion 5, the end edge 30 of the lid disc 26 abuts the abutment
edge 24 of the rib 21 and the boss 31 extends into the opening 20.
[0016] In order to remove the lid disc 26 from the frame 1, pressure must be exerted on
the lid disc 26 close to both its ends, whereby the disc attains the curvature indicated
by the dotted line in Figure 6. The boss is thereby disengaged from the opening 20
and the end edge 29 of the disc is brought out of contact with the abutment edge 24.
The lid disc 26 , its ends still being pressed downwards, is subsequently displaced,
to the right in Figure 6, until the end edge 29 abuts the inner surface 22 of the
frame end portion 4. When pressure is removed from the end portion of the disc situated
close to the rib 17 in this position, the end edge of the disc 29 moves past the edge
35 of the rib and the lid disc can be removed from the lid frame 1 by gripping said
lid discend portion. In order to render possible the displacement of the lid disc
26 to free said lid disc from the frame as described above, there must of course be
a cavity under the end portion 34 extending a distance A beyond the end edge 29 of
the lid disc 26 at least corresponding to the distance B which the opposite end portion
32 of the disc extends under the rib 17.
[0017] Figure 7 is a longitudinal cross-section corresponding to that shown in Figure 6
of an alternative embodiment of a lid according to the invention. The lid comprises
a lid frame 101 and a lid disc 126 mounted therein.
[0018] The lid frame 101 has two parallel frame side portions not shown, said frame side
portions on the interior side being provided with a longitudinal strip 108, having
an upper supporting surface 12. Furthermore, the lid frame 101 has two frame end portions
104, 105, said frame end portions having at their upper end a rib extending inwards
from their inner surface 118, 122. An opening 120, 140 has been provided in each of
these ribs. The lid disc 126 has a width substantially corresponding to the distance
between the interior sides of the frame side portions and has end portions 133, 134
extending under the adjacent rib 121, 117. A boss 141, 131 is provided at each end
portion 134 and 133, said boss engaging the opening 120, 140 of the neighbouring rib
121. Finally, the lid disc 126 rests on the supporting surfaces 112 of the longitudinal
strips 108. These supporting surfaces 112 gradually change into downwards sloping
surfaces 114, 116 at each end.
[0019] The overlapping portions between the ribs 117, 121 of the frame 101 and the corresponding
end portions 33, 34 of the lid disc 126 are shorter than the distance between the
end edges 129, 130 of the lid disc 126 and the inner surfaces 122, 118 of the frame
end portions 104, 105. As a result, the lid disc 126 can be removed from the frame
101 by pressing the disc 126 downwards at its ends and subsequently displacing it
towards the frame end portions, until its edge abuts the interior surface of the frame
end portion, thereby allowing the other end of the lid disc 126 to pass the edge of
the adjacent rib whereby the lid disc can be dismounted from the frame.
[0020] Both the embodiments of the lid according to the invention described above are intended
to be glued at the bottom 6, 106 of the lid frame 1 onto the outer surface of a container
around an opening or a perforation for the formation of an opening in the container.
It is however obvious and lies within the scope of the invention to form the frame
in such a way that it can be fitted in an opening of a container or fastened to a
rim portion of a container.
1. Child proof lid for a container, said lid comprising a lid frame (1, 101) firmly mountable
on the container, and a lid disc (26, 126) detachably and supportedly mounted in the
lid frame, said lid disc having two substantially parallel and opposing lateral edges
(27, 28) and opposite end portions (33, 34; 133, 134) extending under projecting portions
(17, 21; 117, 121) of the frame, charac terised in that the projecting portions of the frame (17, 21; 117, 121) are firm and that
a stop means is provided to prevent the lid disc (26, 126) from being displaced in
relation to the lid frame (1,101) in the plane of the lid disc, that the lid disc
(26, 126) is elastically bendable and supported by protrusions (7, 8; 108) projecting
under the parallel lateral edges of the lid disc (27, 28) at a distance from the end
portions of the lid disc (33, 34; 133, 134) and that the lid frame (1, 101) has a
cavity (36) under the end portions of the lid disc (33, 34; 133, 134), said cavity
at least at the one end portion (33; 133, 134) extending a distance beyond the end
portion, at least corresponding to the distance which the opposite end portion extends
under the superjacent projecting frame portion (17, 117, 121).
2. A lid as claimed in claim 1, characterised by the stop means comprising a boss (141,
131) projecting from each of the end portions (133, 34) of the lid disc (126), said
boss engaging openings (140, 120) in the adjacent projecting frame portion (117, 121).
3. A lid as claimed in claim 1, characterised by the stop means comprising a boss (31)
projecting from the one end portion (33) of the lid disc (26), said boss engaging
an opening (20) in the adjacent projecting frame portion (17) and an edge (29, 30)
of each end portion (33, 34) abuting a corresponding abutment surface (24, 18) on
the interior of the frame (1).
4. A lid as claimed in claim 3, characterised by the end portion (34) not being provided
with a boss (31) only just extends under the superjacent projecting frame portion
(21).
5. A lid as claimed in claim 1, characterised by the supporting protrusions (7, 8; 108)
being longitudinal strips with a substantially plane supporting surface (11, 12: 112),
said supporting surface gradually changing into downwards sloping surfaces (13, 14,
15, 16, 114, 116) at each end.
6. A lid as claimed in claim 1 or 5, characterised by the supporting protrusions (7,
8; 108) being at a distance below the projecting frame portions (17, 21; 117, 121)
substantially corresponding to the thickness of the lid disc (26; 126).