U.S. patent application number 14/698305 was filed with the patent office on 2015-11-05 for suspension arrangement, and a monitoring device having a suspension arrangement.
This patent application is currently assigned to Axis AB. The applicant listed for this patent is Axis AB. Invention is credited to Johan Bergsten, Niclas Moller Lewin, Jens Pahlitzsch.
Application Number | 20150316836 14/698305 |
Document ID | / |
Family ID | 50639292 |
Filed Date | 2015-11-05 |
United States Patent
Application |
20150316836 |
Kind Code |
A1 |
Lewin; Niclas Moller ; et
al. |
November 5, 2015 |
SUSPENSION ARRANGEMENT, AND A MONITORING DEVICE HAVING A SUSPENSION
ARRANGEMENT
Abstract
An assisting suspension arrangement for suspending a monitoring
device, comprising a hook member, a blocking member, and a
resilient member is disclosed. The suspension arrangement is
configured to adopt an open state and a closed state. The
suspension arrangement is configured such that when the monitoring
device is suspended by the suspension arrangement, the hook member
is adapted to carry the weight of the monitoring device and thereby
to move toward the open state; and such that when the load of the
weight of the monitoring device is released from the hook member,
the resilient member is adapted to move the hook member toward the
closed state. A monitoring device comprising such a suspension
arrangement is also disclosed.
Inventors: |
Lewin; Niclas Moller;
(Malmo, SE) ; Pahlitzsch; Jens; (Lund, SE)
; Bergsten; Johan; (Landskrona, SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Axis AB |
Lund |
|
SE |
|
|
Assignee: |
Axis AB
Lund
SE
|
Family ID: |
50639292 |
Appl. No.: |
14/698305 |
Filed: |
April 28, 2015 |
Current U.S.
Class: |
396/427 ;
248/339 |
Current CPC
Class: |
H04N 5/2252 20130101;
F16M 13/02 20130101; G03B 17/561 20130101; F16B 45/02 20130101;
F16B 45/04 20130101 |
International
Class: |
G03B 17/56 20060101
G03B017/56; F16M 13/02 20060101 F16M013/02; H04N 5/225 20060101
H04N005/225; F16B 45/04 20060101 F16B045/04 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 30, 2014 |
EP |
14166574.5 |
Claims
1. An assisting suspension arrangement for suspending a monitoring
device, the suspension arrangement comprising: a hook member; a
blocking member; and a resilient member; wherein the suspension
arrangement is configured to adopt an open state, in which the hook
member is arranged to enable engagement with a suspension element
for suspending a monitoring device, and a closed state, in which
the blocking member is arranged to prevent disengagement of the
suspension element from the hook member; wherein the open state and
the closed state are enabled by the hook member being movable in
relation to the blocking member; wherein the resilient member is
arranged to bias the suspension arrangement toward the closed
state; wherein the suspension arrangement is configured such that
when the monitoring device is suspended by the suspension
arrangement, the hook member is adapted to carry the weight of the
monitoring device and thereby to transfer the load to the resilient
member and to move toward the open state of the suspension
arrangement; wherein the suspension arrangement is configured such
that when the load of the weight of the monitoring device is
released from the hook member, the resilient member is adapted to
move the hook member toward the closed state of the suspension
arrangement; wherein the hook member is provided with a slot being
arranged to receive and contain the suspension element; and wherein
the blocking member comprises an elongated portion extending along
and adjacent to an outer surface of the hook member and transverse
to a side of the slot of the hook member such that the blocking
member prevents a suspension element contained in an engagement
portion from exiting through an entrance portion.
2. The suspension arrangement of claim 1, wherein the slot
comprises an entrance portion, arranged to receive the suspension
element from outside the hook member, and an engagement portion,
arranged to contain the suspension element; and wherein the slot is
arranged such that when the monitoring device is suspended by the
suspension arrangement, the suspension element is forced away from
the entrance portion into the engagement portion of the slot.
3. The suspension arrangement of claim 2, wherein the slot
comprises an additional portion; and wherein the suspension
arrangement is arranged to enable the suspension element to enter
the additional portion or the entrance portion from the engagement
portion when the weight of the monitoring device is released from
the hook member.
4. The suspension arrangement of claim 1, wherein the blocking
member comprises a corresponding elongated portion being arranged
at an other side of the slot.
5. The suspension arrangement of claim 1, further comprising a
foundation member provided with a through-hole for receiving the
hook member, wherein the hook member is provided with a base
portion arranged to prevent passage of the hook member through the
through-hole; and wherein the resilient member is arranged between
the base portion and the foundation member.
6. The suspension arrangement of claim 5, wherein the blocking
member forms part of the foundation member.
7. The suspension arrangement of claim 5, wherein the outer surface
of the hook member is provided with a locking passage; and wherein
the suspension arrangement is configured such that the locking
passage is exposed in the open state to enable reception of a
locking element and such that the locking passage is covered by the
foundation member in the closed state, whereby the suspension
arrangement is prevented from adopting the closed state when the
locking element is arranged in the locking passage.
8. The suspension arrangement of claim 7, wherein the locking
passage extends transverse to a moving direction of the hook
member; and wherein the locking passage is arranged to receive a
locking element in the form of a pin.
9. The suspension arrangement of claim 5, further comprising a
resilient locking element attached to the foundation member,
wherein the hook member is provided with a locking notch; and
wherein the suspension arrangement is configured such that the
locking element is insertable into the locking notch when the
suspension arrangement is arranged in the open state, whereby the
suspension arrangement is prevented from adopting the closed state
when the locking element is arranged in a locking passage.
10. The suspension arrangement of claim 1, wherein an outer side
surface of the hook member is provided with a high friction
portion; and wherein the suspension arrangement is configured such
that the high friction portion is exposed in the open state of the
suspension arrangement.
11. The suspension arrangement of claim 1, wherein the slot forms a
passage for the suspension element; wherein the passage extends
from one side surface of the hook member and past the center axis
of the hook member; wherein the blocking member is arranged
transverse to the passage of the slot in the closed state of the
suspension arrangement such that the blocking member prevents a
wire to pass the slot; and wherein the blocking member is
positioned so as to be arranged transverse to the passage of the
slot regardless of which side of the passage is arranged adjacent
the blocking member.
12. The suspension arrangement of claim 1, wherein the hook member
is provided with a pair of slots each being arranged to receive and
contain the suspension element; wherein the slots comprise entrance
portions which are located on opposite sides of a side surface of
the hook member; wherein the blocking member comprises two blocking
portions; and wherein the blocking portions are arranged to prevent
the suspension element from passing any of the slots, whereby
disengagement of the suspension element from the hook member is
prevented.
13. A monitoring device arranged to be suspended, the monitoring
device comprising the suspension arrangement of claim 1.
14. A monitoring device arranged to be suspended, the monitoring
device comprising a suspension arrangement, the suspension
arrangement comprising: a hook member; a blocking member; and a
resilient member; wherein the suspension arrangement is configured
to adopt an open state, in which the hook member is arranged to
enable engagement with a suspension element for suspending a
monitoring device, and a closed state, in which the blocking member
is arranged to prevent disengagement of the suspension element from
the hook member; wherein the open state and the closed state are
enabled by the hook member being movable in relation to the
blocking member; wherein the resilient member is arranged to bias
the suspension arrangement toward the closed state; wherein the
suspension arrangement is configured such that when the monitoring
device is suspended by the suspension arrangement, the hook member
is adapted to carry the weight of the monitoring device and thereby
to transfer the load to the resilient member and to move toward the
open state of the suspension arrangement; wherein the suspension
arrangement is configured such that when the load of the weight of
the monitoring device is released from the hook member, the
resilient member is adapted to move the hook member toward the
closed state of the suspension arrangement; wherein the hook member
is provided with a slot being arranged to receive and contain the
suspension element; and wherein the blocking member comprises an
elongated portion extending along and adjacent to an outer surface
of the hook member and transverse to a side of the slot of the hook
member such that the blocking member prevents a suspension element
contained in an engagement portion from exiting through an entrance
portion.
Description
FIELD OF INVENTION
[0001] The invention relates to a suspension arrangement, in
particular an assisting suspension arrangement for suspending a
monitoring device.
BACKGROUND
[0002] A suspension arrangement may be used in various applications
for providing suspension of devices such as equipment, fixtures or
decorations. The suspension may be temporary, such as when moving a
piece of equipment by a crane, or permanent such as when installing
a lamp by suspending it in a ceiling.
[0003] One type of suspension arrangement is adapted for suspending
a monitoring device. The monitoring device may be a surveillance
camera adapted for outdoor mounting. The monitoring device may be
attached to a mounting bracket, which in turn is fixed to a wall or
roof structure. The installation of such a monitoring device, which
can be large and heavy, may be facilitated by first attaching the
monitoring device to the mounting bracket such that the monitoring
device is suspended and can hang on its own. An assisting
suspension arrangement may be used for this purpose. The suspension
arrangement may be integrated on a top surface of the monitoring
device's housing.
[0004] The suspension arrangement may comprise a hook member
attached to the monitoring device. The hook member may be
configured to receive a safety wire with a loop extending from the
mounting bracket. Thereby the monitoring device can hang on its own
while the person installing the monitoring device, also referred to
as the monitoring device fitter, connects necessary cables between
the monitoring device and the mounting bracket.
[0005] When the monitoring device is connected as required, the
monitoring device may be fixedly attached to the mounting bracket
by screws or the like. The suspension arrangement need not be
detached and may function as a safety arrangement if the primary
attachment fails or is actively removed. An example of such a
suspension arrangement may be seen in the appended FIG. 1.
[0006] The suspension arrangement may be equipped with a leaf
spring for preventing unintentional unhooking of the safety wire
from the hook member. The hook member may be configured to be
arranged in an open position for receiving the wire by depressing
the leaf spring so as to create a gap, between the leaf spring and
the hook member. The safety wire is passed through the gap. It may
be relatively easy to hook onto the safety wire, but the small gap
obtainable by depressing the leaf spring can make unhooking
difficult. Tests also show that in some situations the hook member
may break, for example because the safety wire hooks onto a part of
the leaf spring instead of the hook.
[0007] From the above discussion, there is evidently a need for
improvement of existing suspension arrangements which are suitable
for suspending a monitoring device.
SUMMARY
[0008] It is an object of the present invention to provide a
suspension arrangement which alleviates the above mentioned and
other drawbacks. It is also an object of the present invention to
provide a suspension member which is easy to use and which provides
a secure engagement of a monitoring device or other device during
suspension.
[0009] According to a first aspect, the invention is an assisting
suspension arrangement for suspending a monitoring device. The
suspension arrangement comprises a hook member, a blocking member,
and a resilient member. The suspension arrangement is configured to
adopt an open state, in which the hook member is arranged to enable
engagement with a suspension element for suspending a monitoring
device, and a closed state, in which the blocking member is
arranged to prevent disengagement of the suspension element from
the hook member. The open state and the closed state are enabled by
the hook member being movable in relation to the blocking member.
The resilient member is arranged to bias the suspension arrangement
toward the closed state. The suspension arrangement is configured
such that when the monitoring device is suspended by the suspension
arrangement, the hook member is adapted to carry the weight of the
monitoring device and thereby to transfer the load to the resilient
member and to move toward the open state of the suspension
arrangement. The suspension arrangement is configured such that
when the load of the weight of the monitoring device is released
from the hook member, the resilient member is adapted to move the
hook member toward the closed state of the suspension arrangement.
The monitoring device may be a camera.
[0010] An advantage of the invention is that the engagement of the
suspension element does not require any interaction between the
monitoring device fitter and the suspension arrangement. By
applying the weight of the monitoring device to the suspension
arrangement, the latter adopts the open state which enables
engagement, i.e. enables that the hook member can hook onto the
suspension element.
[0011] Another advantage of the invention is that the suspension
arrangement is further configured such that it adopts the closed
state when the monitoring device's weight is released from the
suspension arrangement. By this feature, the suspension element is
prevented from disengaging from the suspension arrangement. Thus,
the monitoring device may be moved around, e.g., for connecting a
cable, without any risk of disengaging the suspension element from
the suspension arrangement.
[0012] Yet another advantage of the invention is that the resilient
member provides a damping effect when the monitoring device's
weight is applied to and thus impacts the hook member. This effect
is due to that the hook member transfers the impact force to the
resilient member.
[0013] The functions of enabling engagement and preventing
disengagement are provided by the location of the blocking member
in relation to the hook member in the open state and in the closed
state, respectively. These functions may be provided according to
the following embodiment. The hook member may comprise a slot being
arranged to receive and contain the suspension element. In the
closed state, the blocking member prevents passage of the
suspension element through the slot, but not in the open state. The
slot may comprise an entrance portion, arranged to receive the
suspension element, and an engagement portion, arranged to contain
the suspension element. In such an embodiment, the blocking member
may be arranged to, when the suspension arrangement has adopted the
closed state, prevent passage of the suspension element from the
entrance portion to the engagement portion or the other way
around.
[0014] The blocking member may be arranged as an elongated portion
extending along and adjacent to an outer surface of the hook member
and extending transverse to a side of the slot of the hook member
such that the blocking member prevents a suspension element
contained in the engagement portion from exiting through the
entrance portion.
[0015] The blocking member may comprise a corresponding elongated
portion being arranged at the other side of the slot, i.e. at the
other side of the passage defined by the slot.
[0016] The suspension element may comprise a wire. The wire may
form a wire loop at its end which is provided for the hook member
to engage with, i.e. to hook onto.
[0017] As an example of how the suspension element may be engaged
by the suspension arrangement, the suspension element may be
inserted into the entrance portion of the slot of the hook member
in the above disclosed embodiment. The monitoring device is still
held by the monitoring device fitter such that no substantial force
is applied to the hook member yet. In this position, the monitoring
device fitter can let go of the monitoring device. The weight of
the monitoring device will then be carried by the engagement
between the suspension element and the hook member. The hook member
and the blocking member are forced apart by the vertical force from
the monitoring device's weight whereby the hook member moves upward
in relation to the blocking member. The suspension arrangement
thereby adopts the open state. The downward vertical force from the
monitoring device's weight has been transferred to the resilient
member which is now compressed.
[0018] Thanks to the suspension arrangement, the monitoring device
fitter is free to use both his/her hands to perform any necessary
connections between the wiring of the monitoring device and the
wiring of the mounting bracket. The suspension arrangement thereby
functions as an assisting suspension arrangement.
[0019] When the monitoring device's weight is released from the
hook member, the suspension element is free to move around in the
slot. However, thanks to the configuration of the suspension
arrangement, disengagement of the suspension element from hook
member, by exiting the slot, is prevented by the blocking member,
since the suspension arrangement adopts the closed state when the
monitoring device's weight is released from the hook member.
Unintentional disengagement of the wire from the hook member is
thereby prevented. The monitoring device fitter can thus move the
monitoring device around without having to assure that the wire is
not disengaged from the hook member of the suspension
arrangement.
[0020] In other words, the suspension arrangement is configured
such that disengagement of the wire requires an active action. In
order to retain the suspension arrangement in the open state, such
that the wire can exit the slot, an upward or outward force has to
be applied to the hook member such that it is forced away from the
blocking member. The upward force has to overcome the downward or
inward force provided by the compressed resilient member in the
open state.
[0021] The slot may be arranged such that when the monitoring
device is suspended by the suspension arrangement, the suspension
element is forced away from the entrance portion into the
engagement portion of the slot. This feature may be achieved by for
example that the slot is inclined upward between the entrance
portion and the engagement portion.
[0022] The slot may comprise an additional portion. Moreover, the
suspension arrangement may be arranged to enable the suspension
element to enter the additional portion or the entrance portion
from the engagement portion when the weight of the monitoring
device is released from the hook member. The additional portion
provides an alternative movement path for the wire when moving from
the engagement portion. This feature lowers the risk that the
suspension element disengages from the hook member when the
monitoring device's weight is released from the hook member, if the
return to the closed state is not as fast as required.
[0023] The suspension arrangement may further comprise a foundation
member. The foundation member may be provided with a through-hole
for receiving the hook member. The blocking member may form part of
the foundation member. The hook member may be provided with a base
portion arranged to prevent passage of the hook member through the
through-hole. Moreover, the resilient member may be arranged
between the base portion and the foundation member. In such an
embodiment, the resilient member provides a damping effect for the
impact force on the hook member when the hook member is loaded with
the weight of the monitoring device, compared to if the base
portion were to impact directly against the foundation member.
[0024] The outer surface of the hook member may be provided with a
locking passage. The suspension arrangement may be configured such
that the locking passage is exposed in the open state to enable
reception of a locking element. The suspension arrangement may
further be configured such that the locking passage is covered by
the foundation member in the closed state.
[0025] Thereby, the suspension arrangement may be prevented from
adopting the closed state when the locking element is arranged in
the locking passage.
[0026] The locking passage may extend transverse to the moving
direction of the hook member. Moreover, the locking passage may be
arranged to receive a locking element in the form of a pin. When
the suspension arrangement is arranged in the open state, a pin may
be inserted into the locking passage in such a way that it still
extends out from the locking passage. When the force from the
monitoring device's weight, or any other force applied to the hook
member, is released, the suspension arrangement is prevented from
adopting the closed state by the pin bearing against a surface of
the foundation member.
[0027] In another embodiment, provided for facilitating
disengagement of the suspension member, the suspension arrangement
further comprises a resilient locking element attached to the
foundation member. The hook member is in this embodiment provided
with a locking notch. The suspension arrangement may be configured
such that the locking element is insertable into the locking notch
when the suspension arrangement is arranged in the open state,
whereby the suspension arrangement is prevented from adopting the
closed state when the locking element is arranged in the locking
passage. The locking element is withheld in the locking notch by
the resilient member of the suspension arrangement moving the hook
member toward the closed state. This downward force acts on the
locking element.
[0028] In yet another embodiment, provided for facilitating
disengagement of the suspension element, an outer side surface of
the hook member is provided with a high friction portion. The
suspension arrangement is in this embodiment configured such that
the high friction portion is exposed in the open state of the
suspension arrangement. In the open state, force may be applied to
the high friction portion in a radial direction toward the body of
the hook member. Thus, the hook member is forced against the
foundation member's inner surface of the through-hole. The abutment
creates friction which, when the monitoring device's weight is
released, prevents the hook member from moving toward the closed
state by the resilient member.
[0029] In another embodiment of the invention, the slot forms a
passage for the suspension element and the passage extends from one
side surface of the hook member and past the center axis of the
hook member. The blocking member is in this embodiment arranged
transverse to the passage of the slot in the closed state of the
suspension arrangement such that the blocking member prevents a
wire from passing the slot. The blocking member may be positioned
so as to be arranged transverse to the passage of the slot
regardless of which side of the passage is arranged adjacent the
blocking member. The hook member may thereby be arranged in
different positions.
[0030] In another embodiment of the invention, the hook member is
provided with a pair of slots each being arranged to receive and
contain said suspension element. The slots comprise entrance
portions, which may be located on opposite sides of the hook
member's side surface. In this embodiment, the blocking member
comprises two blocking portions, which are arranged to prevent the
suspension element from passing any of the slots, whereby
disengagement of the suspension element from the hook member is
prevented. An advantage of this embodiment is that the hook member
may be located in a single position, while providing two entrance
directions for the wire.
[0031] According to a second aspect, the invention is a monitoring
device arranged to be suspended. The monitoring device comprises a
suspension arrangement according to any embodiment of the first
aspect above. The monitoring device may be a camera.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The above and other aspects of the present invention will
now be described in more detail, with reference to the appended
drawings showing embodiments of the invention.
[0033] FIG. 1 illustrates a prior art construction of a suspension
arrangement.
[0034] FIG. 2 illustrates a suspension arrangement according to an
embodiment of the invention.
[0035] FIG. 3 is a cross-sectional view of the suspension
arrangement in FIG. 2.
[0036] FIGS. 4a-4d illustrate engagement and disengagement of a
suspension element in a suspension arrangement according to an
embodiment of the invention.
[0037] FIGS. 5-8 are cross-sectional views of different embodiments
of the suspension arrangement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] The present invention will now be described more fully with
reference to the accompanying drawings, in which currently
preferred embodiments of the invention are shown. The invention may
however be embodied in many different forms and should not be
construed as limited to the embodiments set forth herein.
[0039] A prior art construction of a suspension arrangement 1 is
illustrated in FIG. 1. The suspension arrangement 1 may be located
on a top surface 11 of a monitoring device. The monitoring device
may be arranged to be attached to a mounting bracket. The purpose
of the suspension arrangement 1 is to enable suspension of the
monitoring device from the mounting bracket during, for example,
installation of the monitoring device. When the monitoring device
is suspended, the monitoring device can hang freely and the
monitoring device fitter is free to connect any necessary cables
and other connectors between the monitoring device and the mounting
bracket. When this is done, the monitoring device fitter may attach
the monitoring device to the mounting bracket by means of screws or
the like.
[0040] The known suspension arrangement 1 comprises a hook member
10. The hook member 10 is attached to a top surface 11 of the
monitoring device. The suspension arrangement 1 further comprises a
resilient member in the form of a leaf spring 12. The leaf spring
12 is also attached to the top surface 11 of the monitoring
device.
[0041] The leaf spring 12 is arranged to bias toward a position
where it bears against a portion of the hook member 10. The hook
member 10, the leaf spring 12 and the top surface 11 of the
monitoring device define an interior space 14 in this position as
illustrated in FIG. 1. The suspension arrangement 1 is arranged to
receive a safety wire (not illustrated) in the interior space 14 by
the hook member 10 hooking onto the safety wire. The leaf spring 12
is resilient such that it may, in a loaded state, form a gap
between the top of the leaf spring 12 and the hook member 10. The
gap provides an entrance for the wire into the interior space 14.
The leaf spring 12 may be arranged in the loaded state by
depressing the leaf spring 12 inward toward the interior space 14.
The leaf spring 12 is provided with a protruding portion 13 for
facilitating the depression and assisting the monitoring device
fitter when locating the leaf spring 2.
[0042] Although the suspension arrangement 1 is fully functional,
tests have shown that in some situations there is a risk that the
suspension arrangement 1 breaks during use. In particular, the
safety wire, when contained in the interior space 14 and when the
monitoring device is moved around, may locate itself so as to bear
against the protruding portion 13 when the monitoring device is
released. In this situation, the monitoring device's weight is
carried by the leaf spring 12 instead of by the hook member 10 as
intended. The leaf spring 12 may break due to the weight. There is
also a risk that the safety wire slips off the protruding portion
13, whereby the monitoring device falls down until the safety wire
impacts the upper portion of the hook member 10. In such a
situation, the upper portion of the hook member 10 may break due to
the impact force.
[0043] Moreover, by the design of the suspension arrangement 1, it
can be difficult to unhook the safety wire. When the safety wire is
located in the interior space 14, unhooking is performed by
depressing the leaf spring 12 such that a gap between the upper
portion of the leaf spring 12 and the hook member 10 is formed. The
safety wire must then be led out of the interior space 14 through
the gap, which may be difficult to do while holding the monitoring
device at the same time.
[0044] An improved suspension arrangement 2 according to an
embodiment of the invention and with the same purpose, i.e. to
provide means for suspending a monitoring device, is illustrated in
FIG. 2. FIG. 3 is a cross-sectional view of the suspension
arrangement 2.
[0045] The suspension arrangement 2 comprises a hook member 20 and
a foundation member 21. The suspension arrangement 2 comprises a
pair of blocking members 22. However, only one blocking member 22
is necessary for the invention. In this embodiment, each blocking
member 22 forms part of the foundation member 21. Through-out the
rest of the application, reference will be made only to one
blocking member 22 even though a plurality of blocking members may
be arranged. The form and function of the blocking member 22 will
be disclosed further on.
[0046] The hook member 20 forms a separate part, which is
insertable into a through-hole 33 of the foundation member 21. The
through-hole's 33 shape and size is adapted to the shape of the
hook member 20. The hook member 20 is in this embodiment a cylinder
shaped element, but could in other embodiments have an edged
cross-section or other suitable shapes.
[0047] As seen in FIG. 3, the hook member 20 is provided with a
slot 23. The slot 23 extends through the body of the hook member
20. The slot 23 forms a passage in which it is arranged to receive
a suspension element, such as a wire. To this end, the slot 23
comprises an entrance portion 23a which provides an entrance for
the wire from outside the hook member 20 and into the passage of
the slot 23. The slot 23 further comprises an engagement portion
23b for containing the wire when completely received in the slot
23.
[0048] In order to prevent that the hook member 20 passes the
through-hole 33 in the foundation member 21, the hook member 20
comprises a base portion 31. The cross-section of the base portion
31 is arranged such that it cannot pass the through-hole 33. In
this embodiment, the base portion 31 forms a flange which extends
radially outward from the body of the hook member 20.
[0049] By the hook member 20 being separate from the foundation
member 21, the hook member 20 is movable in relation to the
foundation member 21, and in particular in relation to the blocking
member 22.
[0050] The suspension arrangement 2 also comprises a resilient
member in the form of a wave spring 30. The wave spring 30 is a
type of spring also known as coiled wave spring, scrowave spring,
or flat wire compression spring. A wave spring may be made out of
pre-hardened flat wire which is formed as waves during
manufacturing of the spring. A wave spring may be formed with
different numbers of turns and waves which defines the spring
characteristics.
[0051] It is appreciated that other forms of springs are also
feasible, such as plate springs and coiled springs. It is also
feasible to provide the spring function in the form of an
elastomeric material, such as a ring or sleeve of a suitable
elastomer, which may be slipped onto the body of the hook member.
Hydraulic springs are also possible to use.
[0052] The resilient member could be a separate part, as in the
illustrated embodiments, or be integrated in either the hook member
or in the foundation member of the suspension arrangement.
[0053] The embodiments illustrated in the drawings comprise
resilient members in the form of wave springs 30. It is appreciated
that these wave springs 30 may be substituted by other forms of
resilient members, such as the spring types exemplified above.
[0054] Returning to FIG. 3, the wave spring 30 forms a closed
circle which is slipped onto the body of the hook member 20. When
the hook member 20 is positioned in the through-hole 33 of the
foundation member 21, the wave spring 30 is arranged between the
base portion 31 and the foundation member 21. The wave spring 30 is
thereby sandwiched between the base portion 31 and the foundation
member 21.
[0055] The wave spring 30 is arranged to influence the movement of
the hook member 20. By its position, the wave spring 30 is
compressed and thus loaded when the hook member is moved upward in
the figure. The wave spring 30 thus provides a counteracting
downward force when moving the hook member 20 upward in the figure.
When the counteracting downward force is no longer overcome by the
upward force, the hook member 20 is moved downward in the figure
due to decompression of the wave spring 30.
[0056] By upward and downward movement is meant, within the context
of this application, the hook member's 20 movement in relation to
the foundation member 21, and in particular in relation to the
blocking member 22. In other words, the upward direction is defined
as the direction in which the hook member 20 moves through the
through-hole 33, outwardly, toward the open state. The downward
direction is defined as the direction in which the hook member 20
moves through the through-hole 33, inwardly, toward the closed
state.
[0057] It is appreciated that the suspension arrangement does not
need to be oriented such that the hook member moves in a strict
vertical direction. This orientation is chosen for the illustrated
embodiments for facilitating the understanding of the invention. An
orientation of the suspension arrangement such that the hook member
is movable in relation to the blocking member in essentially the
vertical direction is preferred since the force of the monitoring
device's weight generally acts in a downward vertical
direction.
[0058] Returning to FIG. 3, two positions between which the hook
member 20 is movable may be defined: a first position in which the
wave spring 30 is compressed and a second position in which the
wave spring 30 is relaxed when compared to the first position.
[0059] It is appreciated that the wave spring 30 does not need to
be fully relaxed in the second position. The suspension arrangement
2 may, for example, be arranged such that the wave spring 30 is
slightly compressed in the second position.
[0060] Two states of the suspension arrangement are defined within
the context of this application: an open state and a closed state.
In the open state, the hook member 20 is arranged in the first
position and the suspension arrangement 2 is configured to enable
engagement between the hook member 20 and a suspension member. In
the closed state, the hook member 20 is arranged in the second
position and the suspension arrangement 2 is configured to prevent
disengagement of the suspension element from the hook member
20.
[0061] The functions of enabling engagement and preventing
disengagement are provided by the location of the blocking member
22 in relation to the hook member 20 in the open state and in the
closed state, respectively.
[0062] The open state and closed state of the suspension
arrangement 2 will now be disclosed in detail with reference to
FIGS. 4a-4d illustrating an example of how to use the suspension
arrangement 2.
[0063] A monitoring device in the form of a camera 4 comprising a
camera housing 40 and a camera dome 41 is illustrated in FIG. 4a.
The term camera is within the context of this application to be
construed as a camera module or a camera arrangement which may
comprise components other than a camera unit, such as housing
components, connectors, processors, lighting arrangements, lenses
or other optical components, etc.
[0064] The camera 4 is arranged to be installed as a suspended
camera. For this purpose, a mounting bracket 42 is provided. The
mounting bracket 42 is arranged to provide attachment of the camera
4 to a mounting surface. The mounting surface is a wall in this
example, but could be other surfaces such as a ceiling or soffit
structure. The mounting bracket 42 and camera 4 may be installed in
an indoor or in an outdoor environment.
[0065] The mounting bracket 42 comprises a mounting portion 46
arranged to be fixed to the wall, by means of, e.g., screws. The
mounting bracket 42 further comprises a camera arm 47 which is
arranged to connect to the camera 4. The camera arm 47 may house
power cords and other wiring to be connected to the camera 4.
[0066] The top surface of the camera housing 40 is provided with a
cover 48 covering an opening 49 in a top surface of the camera
housing 40. The opening 49 provides access to wiring located in the
interior of the camera 4 which is to be connected to the wiring of
the mounting bracket's 42 camera arm 47. Hence, no wiring or
connections need to be located neither outside the mounting bracket
42 nor outside the camera 4. The wiring and cable connections are
thus protected from influences from the outside, such as rain or
physical damage.
[0067] In order to provide this protection, the wiring in the
interior of the camera housing 40 must be connected to the wiring
in the mounting bracket 42 before the camera housing 40 is attached
to the camera arm 47. The suspension arrangement 2 assists in this
process. The mounting bracket 42 is provided with a suspension
element in the form of a wire 43 and the camera 4 is provided with
the suspension arrangement 2. The suspension arrangement 2 may be
provided outside or within the opening 49.
[0068] The wire 43 is here provided with a wire loop at its end.
The wire loop enables engagement to the hook member 20 by the hook
member 20 hooking onto the wire loop. The material of the wire may
be metal, a polymeric material, or an organic material, such as
hemp.
[0069] The suspension arrangement 2 in combination with the wire 43
allows the camera 4 to be suspended in the mounting bracket 42 and
to hang by itself, without the need for the camera fitter to hold
the camera 4. The camera fitter may thereby be free to use both
his/her hands to perform the necessary connections between the
wiring of the camera 4 and the wiring of the mounting bracket 42.
When these are accomplished, the camera fitter may lift up the
camera 4 and attach it to the camera arm 47 of the mounting bracket
42. The attachment may be performed by screws or the like.
[0070] Going more into detail, the engagement between the hook
member 20 and the wire 43 and the function of the blocking member
22 will now be disclosed with reference to FIGS. 4b-4d.
[0071] As disclosed earlier, the suspension arrangement 2 is
configured to adopt the closed state when no upward force is
applied to the hook member 20. In the closed state, the hook member
20 and the blocking member 22 are located in relation to each other
such that the blocking member 22 prevents passage of the wire 43
through the slot 23. By passage is meant passage from the entrance
portion 23a to the engagement portion 23b or the other way
around.
[0072] In the embodiment illustrated in FIGS. 4b-4c, the blocking
member 22 comprises an elongated portion extending along and
adjacent to an outer surface of the hook member's 20 body. The
blocking member 22 extends transverse to a side of the slot 23,
meaning that the blocking member 22 extends transverse to a side of
the passage which the slot 23 forms for the wire 43. As previously
mentioned, the suspension arrangement 2 may comprise a further
blocking member extending along the other side of the slot 23, i.e.
along the other side of the passage.
[0073] The gap distance between the blocking member 22 and the hook
member 20 is adapted such that the particular suspension member
used cannot pass the gap. A small gap is preferred, instead of the
blocking member 22 abutting against the hook member 20, in order to
not create any friction between the hook member 20 and the blocking
member 22.
[0074] The blocking member 22 is arranged transverse to an
intermediate portion of the slot 23 between the entrance portion
23a and the engagement portion 23b. The wire 43 may thereby be
arranged in the entrance portion 23a of the slot 23 when the
suspension arrangement 2 is still arranged in the closed state.
This is illustrated in FIG. 4b, where the wire 43 has been inserted
into the entrance portion 23a of the slot 23. The camera 4 is still
held by the camera fitter such that no substantial force is applied
to the hook member 20 yet. In this position, the camera fitter can
let go of the camera 4. The weight of the camera 4 will then be
carried by the engagement between the wire 43 and the hook member
20. The hook member 20 and the foundation member 21 are forced
apart by the downward vertical force from the camera's weight,
whereby the hook member 20 moves upward in relation to the blocking
member 22. The suspension arrangement 2 thereby adopts the open
state which is illustrated in FIG. 4c. The downward vertical force
from the camera's 4 weight has been transferred to the wave spring
30 which is now compressed.
[0075] In the open state, the wire 43 is allowed to pass the slot
23 from the entrance portion 23a to the engagement portion 23b. Due
to that the slot 23 is inclined upward from the entrance portion
23a to the engagement portion 23b, the wire 43 is forced away from
the entrance portion 23a into the engagement portion 23b of the
slot 23 when the camera fitter lets go of the camera 4.
[0076] When the wire 43 is received in the engagement portion 23b
the hook member 20 is exposed to an impact force. The suspension
arrangement 2 is configured such that the impact force exerted on
the hook member 20 is transferred to the wave spring 30. The wave
spring 30 thereby provides a damping effect for the impact when the
hook member 20 is loaded with the weight of the camera 4, compared
to if the base portion 31 were to impact directly against the
foundation member 21.
[0077] FIG. 4d illustrates how the suspension arrangement 2 acts
when the force from the camera's 4 weight is released from the hook
member 20. The solid lines of the wire 43 and of the suspension
arrangement represent the open state of the suspension arrangement
2, in which the hook member 22 carries the camera's weight. The
broken lines of the wire 43 and of the suspension arrangement
represent the closed state of the suspension arrangement 2, in
which the camera's weight is released from the hook member 22. Due
to the compression of the wave spring 30 in the closed state, the
wave spring 30 is arranged to bias the suspension arrangement 2
toward the closed state.
[0078] When the camera's weight is released from the hook member
20, the wire 43 is no longer forced into the engagement portion 23b
and may move along the slot 23. However, thanks to the
configuration of the suspension arrangement 2, exit of the wire 43
from the slot 23 through the entrance portion 23a is prevented by
the blocking member 22 since the suspension arrangement 2 adopts
the closed state when the camera's weight is released from the hook
member 20. Unintentional disengagement of the wire from the hook
member 20 is thereby prevented. The camera fitter can thus move the
camera around without having to assure that the wire 43 is not
disengaged from the hook member 20 of the suspension arrangement
2.
[0079] In other words, the suspension arrangement 2 is configured
such that disengagement of the wire 43 requires an active action.
In order to retain the suspension arrangement 20 in the open state,
such that the wire 43 can exit the slot 23, an upward force has to
be applied to the hook member 20 such that it is forced away from
the blocking member 22. The upward force has to overcome the
downward force provided by the compressed wave spring 30 in the
open state. One example is that the camera fitter pulls the hook
member 20 in the upward direction, so as to arrange the suspension
arrangement 2 in the open state, while leading the wire 43 out from
the slot 23.
[0080] Another example of how to disengage the wire 43 from the
slot 23 will be disclosed with reference to FIG. 4c. Here, the hook
member 20 is provided with a high friction portion 45 which
facilitates the disengagement of the wire 43. The high friction
portion 45 is located at a position which is exposed when the
suspension arrangement 2 adopts the open state. In the open state,
the fitter may apply force to the high friction portion 45 in a
radial direction toward the body of the hook member 20. Thus, the
hook member 20 is forced against the foundation member's 21 inner
surface of the through-hole 33. The forced abutment creates
friction which, when the camera's weight is released, prevents the
hook member 20 from moving toward the closed state by the wave
spring 30. The high friction portion 45 could for example be a
grooved, knurled, or roughed surface portion. Force may be applied
to the high friction portion 45 by pressing a tool or a finger
against it. When the wire 43 has been disengaged, the force applied
to the high friction portion 45 may be released whereby the
suspension arrangement 2 adopts the closed state.
[0081] The hook member 20 of FIG. 4c is also provided with a
locking passage 44. The locking passage 44 may form an alternative
or a complement to the high friction portion 45. The locking
passage 44 is arranged at a position on the hook member 40 such
that the locking passage 44 is exposed in the open state and
covered by the foundation member in the closed state. In other
words, the portion of the hook member 20 which is provided with the
locking passage 44 is located in the through-hole 33 of the
foundation member 21 when the suspension arrangement adopts the
closed state. The locking passage 44 extends in a tangential
direction in view of the hook member's 20 cross-sectional
circumference. Alternatively, the locking passage 44 may extend in
a radial direction in view of the hook member's 20 cross-section or
in a shifted direction thereof.
[0082] The locking passage 44 is configured to receive a locking
element in the form of a pin (not illustrated). When the suspension
arrangement 2 is arranged in the open state, the pin is inserted
into the locking passage 44 in such a way that it still extends out
from the locking passage 44. When the force from the camera's 4
weight, or any other force applied to the hook member 20, is
released, the suspension arrangement is prevented from adopting the
closed state by that the pin bear against a surface of foundation
member 21. The wire 43 can thus be removed from the slot 23 without
the need for applying any active force on the hook member 20. When
the wire 43 has been disengaged, the pin may be removed from the
locking passage whereby the suspension arrangement adopts the
closed state. The pin may be provided with a conspicuous flag, or
be designed in a conspicuous colour, in order to reduce the risk of
the fitter forgetting to remove it after use. The pin may be
attached to the suspension arrangement 2, e.g. to a portion of the
foundation member 21 for making the pin easily accessible.
[0083] The suspension arrangement is in the disclosed embodiment is
arranged to be provided on the top surface of a camera 4. It is
appreciated that the suspension arrangement 2 may alternatively be
located in the mounting bracket 42 or in a corresponding
arrangement to which the camera 4 is to be attached. The suspension
member, in this example the wire 43, would in that case be attached
to the camera 4.
[0084] A blocking member 52 according to an alternative embodiment
will now be disclosed with reference to FIG. 5. FIG. 5 is a
cross-sectional view looking in the extension direction of the slot
53. The slot 53 forms a passage for the suspension element, here in
the form of a wire. The passage extends from the entrance portion
53a to the engagement portion 53b. The passage extends past the
center axis of the hook member 50. The blocking member 52 is
arranged transverse to the passage of the slot 53 so as to prevent
a wire from passing the passage when the suspension arrangement is
arranged in the closed state, as it is in FIG. 5. In this
embodiment, the blocking member 52 is positioned so as to be
arranged transverse to the passage of the slot 53 regardless of
which side of the passage is arranged adjacent the blocking member
52. In other words, the suspension arrangement is configured such
that the hook member 53 may be arranged with its entrance portion
53a either facing inward and toward the center of the foundation
member 51 or facing outward and away from the center of the
foundation member 52, as in the illustrated embodiment. Looking at
the suspension arrangement 2 of FIG. 2, the hook member 20 in that
embodiment is arranged such that the engagement portion 23a faces
inward and toward the center of the foundation member 21. In either
of the mentioned positions, the blocking member 52 prevents passage
of a wire through the passage of the slot 53.
[0085] The hook member 20 may thereby be arranged in different
positions. Depending on for example the suspension arrangement's
position on the monitoring device, it may be preferred to locate
the hook member 50, and thereby the entrance portion 53a of the
slot 53, differently in order to facilitate the engagement of the
suspension member.
[0086] The base portion of the hook member 50 may be configured so
as to guide the hook member 50 into one of the positions. For
example, the shape of the base portion's circumference may be
chosen such that it fits uniquely into a corresponding recess
arranged for the base portion and provided as a part of the
through-hole 54 of the foundation member 21. For the embodiment in
FIG. 5, where the hook member 50 may be arranged in two positions,
the base portion and the corresponding recess may be arranged such
that both positions are feasible.
[0087] Another embodiment of a hook member 60 is illustrated in
FIG. 6. The slot 63 of the hook member 60 comprises an entrance
portion 63a and an engagement portion 63b, corresponding to the
above disclosed configurations of hook members. The slot 63 also
comprises an additional portion 63c. The additional portion 63c is
arranged in connection with the engagement portion 63b such that a
wire may move within the slot 63 from the engagement portion 63b
into the additional portion 63c. The additional portion 63c has no
opening through which the wire can exit the slot 63.
[0088] The purpose of the additional portion 63c is to provide an
alternative movement path to the entrance portion 63a for the wire
when moving from the engagement portion 63b. This feature lowers
the risk of the wire exiting the slot 63 when the monitoring
device's weight is released from the hook member 60, if the return
to the closed state is not as fast as required. For example, a
resilient member with a low stiffness constant provides a situation
where a low force is required to arrange the suspension arrangement
2 in the open state and where the return to the closed state is
slower when compared to if a resilient member of a higher stiffness
constant is used. When a resilient member with a low stiffness
constant is used, an additional portion 63c may be utilized for
counteracting the drawbacks of a slow return.
[0089] The additional portion 63c is in this embodiment arranged
along the extension direction of the hook member 60. This feature
increases the likeliness that the wire enters the additional
portion 63c, instead of exiting through the entrance portion 63a,
when the monitoring device is lifted in the direction of the
extension direction.
[0090] Yet another embodiment of a hook member 70 is illustrated in
FIG. 7. The hook member 70 is provided with two slots 73' and 73''.
The slots 73', 73'' are located with their entrance portions on
opposite sides of the hook member's 70 side surface. The slots 73',
73'' are not connected to each other.
[0091] This embodiment is an alternative to the embodiment
illustrated in FIG. 5, where the hook member 50 may be positioned
in different positions in order to locate the entrance portion 53a
such that it faces different directions.
[0092] The blocking member 72 comprises two blocking portions 72a
and 72b. Each of the blocking portions 72a, 72b prevents, in the
closed state, a wire from exiting each of the slots 73', 73'',
respectively. The function and form of the blocking member 72 and
of each of the blocking portion 72a, 72b may otherwise accord with
blocking members of previously disclosed embodiments.
[0093] By the configuration of the hook member 70 and the blocking
member 72, the hook member 70 may be located in a single position
in the through-hole 74 of the foundation member 71, while providing
two entrance directions for the wire. It is thereby not required to
reposition the hook member 70 in order to change the entrance
direction for the suspension element from one to another.
[0094] An alternative embodiment of the hook member 21, with
respect to locking the suspension arrangement 2 in the open state,
is illustrated in FIG. 8. The hook member 20 comprises a slot 23
according to previously disclosed embodiments. The foundation
member 21 with the blocking member 22 may be arranged according to
previously disclosed embodiments. The foundation member 21 is
further provided with a locking element 81. The locking element 81
has the form of a resilient pin or strip which is attached to an
upper surface of the foundation member 21. The hook member 20 is
provided with a locking notch 82. The locking notch 82 is provided
on a portion of the hook member 20 which is exposed when the
suspension arrangement is arranged in the open state.
[0095] The locking element 81 and the locking notch 82 are located
in relation to each other such that the locking element 81 is
insertable into the locking notch 82 when the suspension
arrangement is arranged in the open state. By the locking element
81 being resilient, the locking element 81 may be bent for
insertion into the locking notch 82 while still being attached to
the foundation member 21. The locking element 81 could for example
comprise a leaf spring element. The locking notch 82 and the
locking element 81 may be provided in other forms and
configurations.
[0096] The locking arrangement in FIG. 8 may be arranged to provide
a temporary locking of the hook member 20 which is released when
the monitoring device is released. This function is provided by the
suspension arrangement 2 being arranged such that the locking
element 81 is insertable into the locking notch 82 when the hook
member 82 is not moved fully toward the open state, however enough
so that the blocking member 22 does not fully prevent passage of
the wire 43 in the slot 23. The suspension arrangement is thus in
its open state in the locked position. The locking element 81 is
maintained in the locking notch 82 by the wave spring (not
illustrated) of the suspension arrangement moving the hook member
20 toward the closed state. This downward force acts on the locking
element 81.
[0097] When an upward force, which is opposite to and overcomes the
downward force of the wave spring 30, is applied to the hook member
20, by for example the monitoring device's weight, the hook member
20 moves further into the open state. This position is represented
by the dashed lines in FIG. 8. In this position, the locking
element 81 will no longer be maintained in the locking notch 82
since the decompression force of the wave spring 30 is now not
strong enough to move the hook member 20 toward the closed state.
The locking element 81 is arranged to be biased toward a relaxed
state which in this embodiment is an upright state. This state is
indicated by the dashed lines in FIG. 8. Due to this configuration,
the locking element 81 will return to its relaxed state when the
hook member 20 carries the weight of the monitoring device or is
exposed to a corresponding upward force. When the upward force is
released, provided that the locking element 81 is not re-inserted
into the locking notch 82, the suspension arrangement will adopt
the closed state.
[0098] The temporary locking may be used when it is desired to
temporary disengage and re-engage the wire 43. Another use of the
temporary locking is to arrange the suspension arrangement 2 in the
locked position before commencing the mounting process, in order to
facilitate the engagement. The monitoring device could for example
be delivered with the suspension arrangement in the locked
position.
[0099] When an understanding of the principles of the invention now
has been given, it should also be appreciated that the suspension
arrangement may be realized in various forms within the scope of
invention according to the claims.
[0100] It is appreciated that various forms of springs with
different stiffness constant can be chosen. A high stiffness
constant provides a good damping effect when the force from the
monitoring device's weight impacts the hook member. On the other
hand, with a high stiffness constant a greater force is required to
move the hook member toward the open state. In that case, the
embodiments of FIG. 4b (with a locking passage 44 and a pin) and
FIG. 8 (with a locking notch 82 and a locking element 81) may
facilitate disengagement of the wire. Hence, the choice of spring
and its characteristics is flexible and depends on the application
and the desired properties of the suspension arrangement. The
choice also depends on the type of monitoring device that the
suspension arrangement is to be used with. A monitoring device,
such as a camera, arranged for suspension may have a weight of 3-8
kg; however the suspension arrangement may be used for both lighter
and heavier constructions by adapting its configuration. One
control factor for the design is for example that the spring is
chosen such that the vertical force from the monitoring device's
weight when carried by the hook member is large enough to overcome
the downward force of the spring which acts to move the hook member
toward the closed state.
[0101] The material of the suspension arrangement's components
should also be chosen based on the loads it is intended to bear.
For suspending light devices, such as a small camera, the
suspension arrangement, including the foundation member (with the
blocking member), the hook member and the resilient member, may be
made in a polymeric material, such as plastics or rubber. Plastic
materials, for example, have the advantage that they are
inexpensive. However, the material does not sustain as high loads
as some other materials. For suspending heavier devices, the
suspension arrangement may be made in a metal material, such as
steel or aluminum.
[0102] In the embodiments shown on the drawings, the suspension
element is in the form of a loop on a wire. However, the suspension
element may as well take other forms. For instance, a bulge or ball
may be attached to or formed on the wire. The hook member may in
such case be formed with an undercut groove into which the bulge or
ball is insertable, and which has an end wall not allowing the
bulge or ball to pass out of the groove when the monitoring device
is suspended. It may also be possible to use a wire without a loop,
and lock the suspension element in the hook member by means of a
spring-loaded ball lock mechanism. Further, instead of a wire, a
band of elastomeric or plastic material, optionally comprising a
metallic cord may be used. A hook, not forming a complete loop, of
thicker material could also be used as suspension element.
[0103] The hook member need not necessarily be made in one piece.
Instead, it may be made up of two or more parts, of one or more
materials. For instance, an upper part of the hook member,
comprising the slot, may be made of one material, and a lower part,
comprising the base portion, may be made of another material. One
of the parts may, e.g., be screwed into the other part by a
threaded engagement. The shape of the hook member is not limited to
the ones shown on the drawings. The hook member may take any form
suitable for engaging and retaining the respective suspension
element that is being used.
[0104] Above, the invention has been described in connection with a
camera. However, other monitoring devices, such as IR detectors and
microphones, may also be suspended using a suspension arrangement
according to the invention.
[0105] It is also appreciated that the suspension member may be
used for other applications than suspending a monitoring device.
For instance, it may be used for suspending stage equipment, such
as spotlights. The suspension arrangement could be increased or
decreased in size in order to fit the particular application.
[0106] Another suspension arrangement based on the same principles
as the already disclosed embodiments will now be described. The
suspension arrangement comprises a hook member, a foundation member
and a blocking member. The hook member comprises a slot. The
suspension arrangement differs from the above disclosed embodiments
in that the hook member forms part of, or is at least fixedly
attached to, the foundation member. The blocking member is arranged
at least partly around the hook member, as disclosed previously.
The suspension arrangement is configured such that the blocking
member is movable in relation to the hook member. This feature may
be achieved by the suspension arrangement comprising a resilient
member which is provided as a connection between the blocking
member and the foundation member. The suspension arrangement may be
configured such that the resilient member biases the blocking
member toward the closed state. The meaning of closed and open
state is the same as for previously disclosed embodiments. The
suspension arrangement may adopt the open state by that a force,
which counteracts the biasing force of the resilient member, is
applied to the blocking member. The blocking member transfers the
counteracting force to the resilient member which thereby is
compressed. A wire, or other suspension element, may in the open
state be arranged in the slot of the hook member. The blocking
member may thereafter be released whereby the resilient element
moves the blocking member toward the closed state of the suspension
arrangement.
* * * * *