Field of the Invention
[0001] The present invention relates to the technical field of exhaust hose reeling devices,
i.e. industrial reeling devices of the kind comprising an exhaust hose, a rotatably
mounted drum for storing the exhaust hose, and at least one spring, preferably a coil
spring, for winding the exhaust hose onto the drum.
Background Art
[0002] Reeling devices are used in the industry in working areas that are to be kept free
from harmful exhaust gases. The reeling device is usually mounted in the ceiling or
on a wall.
[0003] Reeling devices are for instance known from US 3,049,317, EP 0 968 952, US 3,822,719
and US 1,674,512.
[0004] US 3,049,317 disclose a spring loaded self compensating device having a flexible
member and means to exert an opposing force upon extraction thereof from its housing
to effect a rewinding of the member.
[0005] EP 0 968 952 disclose a retractable hose reel assembly comprising a reel rotatably
mounted in a casing and a torsion spring for rotating the reel in a direction corresponding
to winding of the hose on the reel.
[0006] US 3,822,719 disclose an apparatus for removing of gas and similar fluids from closed
areas comprising a frame in which a drum is rotatably mounted. An outlet socket is
set axially into one end of the drum in fixed relation to the frame and a hose is
wound on the drum and has one end connected inside the drum to the outlet socket.
A spiral spring device is mounted on a shaft fixed axially to the other end of the
drum for rotating the drum to wind up the hose. Stop elements are provided on the
hose and the frame to stop the winding of the drum and a releasable catch is secured
to the frame and cooperates with tooth segments on the spring device to hold the drum
in the desired position.
[0007] US 1,674,512 disclose a reel for supporting a tube for conveying air to the tires
of an automobile and means for supplying the air from the pump to the reel and tube.
[0008] When needed for use, the user grasps a nozzle on the coiled exhaust hose and simply
pulls out the required length of hose before connecting the nozzle to the exhaust
pipe of the vehicle. As a result of the reeling-out operation, the reel spring, or
springs, is tensióried. In the desired pulled-out position, the hose is prevented
from being unintentionally wound in by means of a ratchet mechanism. After use, and
after the nozzle has been disconnected, the user pulls the exhaust hose to release
the ratchet mechanism and thereby allow the tensioned spring to drive the drum in
the direction of winding in the hose.
[0009] Prior art further comprises motor-driven drums, in particular for heavy and/or long
exhaust hoses. In this case, the drum is not controlled by means of the hose, but
by means of a separate handheld control unit, which is connected to the motor drive
by way of a cable or a remote control.
[0010] To handle the large, heavy-duty springs required to wind in heavy exhaust hoses,
it is known to use separate spring cassettes for handling and mounting the springs.
More particularly, each spring cassette can comprise a spring housing, a coil spring
arranged in the spring housing, the outer end of which is attached to the housing,
and an output or drive shaft, which is driven by the spring and connected to and rotated
by the inner end of the spring. The spring cassette is mounted in such manner that
the output shaft driven by the spring is concentric with and directly connected to
the drum for driving it in the direction of winding in the hose.
[0011] To wind in heavy/long exhaust hoses, it is known to connect a plurality of such spring
cassettes in parallel, and also to use spring cassettes which hold more than one spring.
[0012] One disadvantage of exhaust hose reeling devices according to prior art is that the
spring/springs have to be dimensioned directly in dependence on the weight of the
exhaust hose to be wound in. In heavy applications, it is not enough to use powerful
and, thus, bulky springs to obtain the moment of force required to wind in the hose,
and therefore more than one spring arranged in one or more cassettes is often needed.
In particularly demanding applications, motor drive may be the only alternative.
[0013] Thus, exhaust hose reeling devices according to prior art have the disadvantage of
requiring powerful springs and/or a plurality of cooperating springs to handle heavy
exhaust hoses. This, in turn, results in a number of problems.
- 1. When a great moment of force is required for the winding-in operation, solutions
involving spring drive are complicated, or even impossible, and sometimes motor drive
is the only alternative.
- 2. Large, heavy-duty springs may be both difficult to handle and expensive, and the
safety requirements are considerable.
- 3. Large, heavy-duty springs are disadvantageous from the point of view of construction,
since large forces are exerted on the surrounding components, and special dimensions
and design solutions are therefore needed. Prior-art racks for exhaust hose reeling
devices are traditionally made of sheet iron to take up relatively high loads.
- 4. Using a plurality of springs/spring cassettes results in increased overall reel
dimensions, which is undesirable from a practical as well as an aesthetic point of
view.
Summary of the Invention
[0014] A general object of the present invention is therefore to provide an improved exhaust
hose reeling device.
[0015] More particularly, it is an object to provide an exhaust hose reeling device involving
one or more of the following improvements:
- reduction/elimination of the problems associated with the use of large/heavy-duty
springs.
- reduction/elimination of the problems associated with the use of a plurality of springs/spring
cassettes connected in parallel.
- simplified/cheaper construction and manufacture.
- a construction of lower weight.
[0016] According to a first aspect, an exhaust hose reeling device is provided, which in
per se known manner comprises an exhaust hose, a rotatably mounted drum for winding
in and reeling out the exhaust hose, and a shaft, called spring shaft, which is driven
by at least one spring means adapted to wind in the exhaust hose and having an inner
end and an outer end, the reeling device being characterised in that a downshift occurs,
at least when the exhaust hose is wound in, which is such that the speed of the spring
shaft relative to the outer end of the spring means is higher than the speed of the
drum.
[0017] This first aspect is thus based on the idea of using a downshift transmission between
the spring/springs and the drum in such manner that the speed of the drum, at least
when the exhaust hose is wound in, is lower than the speed of the spring shaft relative
to the outer end of the spring means.
[0018] One advantage of using a downshift transmission is that the moment of force exerted
by the spring on the spring shaft does not have to be as great as in traditional direct
drive constructions in order to drive the drum during the winding-in operation.
[0019] This, in turn, gives additional advantages related to design, function and operation.
[0020] One direct advantage is that the need for large springs/a plurality of springs can
be essentially eliminated. At the same time, the downshift allows entirely new, advantageous
manufacturing solutions and user functions, as will be described below.
[0021] One advantage is, thus, that the spring can be so dimensioned relative to the drum
and the exhaust hose that, in an imaginary construction without said downshift and
with a speed ratio of 1:1, it would not allow the whole hose to be wound in.
[0022] Accordingly, in a given application according to the first aspect, it is possible
to use weaker springs, smaller springs and fewer springs. The stress on surrounding
components is advantageously reduced, which makes overall constructional requirements
less exacting and reduces the cost of manufacture.
[0023] One advantage of using smaller and weaker springs is generally simplified and safer
maintenance and handling of the springs.
[0024] One particular advantage of reducing the stress on the surrounding components is
that the exhaust hose reeling device can be designed without a big, heavy and bulky
spring cassette for storing the spring and for absorbing the considerable spring forces.
Thus, a reeling device according to this first aspect can be implemented using a considerably
simpler spring cassette or - as will be described below - without the need for a separate
spring cassette.
[0025] To achieve the speed-reducing downshift, the reeling device can comprise varying
types of downshift transmission means. One embodiment of a reeling device according
to the first aspect comprises a downshift gear transmission. Such a gear transmission
can comprise at least one gear wheel or gear rim. In one embodiment, the spring shaft
drives a small gear wheel, which in turn drives a gear rim, such as an internal gear
rim, which is torsionally rigidly connected to the drum.
[0026] The gear rim can be mounted on the outside of an end wall of the drum, thus ensuring
uniform driving of the drum. Arranging the gear rim on the drum end wall also saves
space in the axial direction between the drum and the rack.
[0027] In one embodiment, the gear rim can be made in one piece with the drum end wall.
Owing to this embodiment, even more reliable transmission between the gear rim and
the drum end wall is obtained. In addition, the construction is simplified and, thus,
the manufacture thereof made less complicated and less expensive.
[0028] In particular, the gear rim can be made in one piece with the drum end wall of a
material comprising at least one of a polymer material and an aluminium material.
Using any of these materials makes the reeling device lightweight and inexpensive,
and improves the design options regarding the rack parts, for example in the case
of injection moulding. The choice of material also affects the mounting of the reeling
device, whose weight will be lower.
[0029] Other types of gear transmission can comprise additional transmission steps. A reeling
device having one gear transmission can be made very compact, both axially and radially
relative to the axis of rotation of the drum, while, at the same time, safe and reliable
driving is obtained.
[0030] The downshift transmission can be supplemented with a means for setting the desired
winding-in moment of force. If such a setting means is provided between the spring
shaft and the downshift transmission, i.e. on the side of the transmission having
the comparatively higher speed, the speed-downshift will allow for a finer setting
"resolution" for the winding-in moment of force, i.e. it will be easier to balance
the reeling device properly.
[0031] The spring means of the exhaust hose reeling device can consist of a coil spring.
Coil spring here means a spring which is spirally wound and essentially flat in the
axial direction. When necessary, more springs, usually connected in parallel, can
be used.
[0032] In one embodiment, the reeling device further comprises a rack arm which supports
the drum, said rack arm having a space, called spring housing, for receiving the spring.
By providing a spring housing in the rack arm itself, a reeling device that is easy
to mount is obtained. Moreover, the simple design means reduced costs of mounting
and manufacture. The spring housing can be completely or partially recessed in the
rack arm, thus allowing the overall axial dimension of the reeling device to be reduced.
[0033] The rack arm can be made of a material comprising at least one of a polymer material
and an aluminium material. Choosing such a material makes the rack arm less expensive
to manufacture and reduces its weight.
[0034] The limiting walls of the spring housing can be formed in one piece with the rack
arm using a material that comprises at least one of a polymer material and an aluminium
material.
[0035] The spring shaft may be eccentrically arranged relative to the axis of rotation of
the drum, which may advantageously reduce the axial dimension of the reeling device.
[0036] According to a second aspect, an exhaust hose reeling device is provided, comprising
a rack arm, an exhaust hose, a drum which is rotatably mounted in the rack arm and
adapted to wind in and reel out the exhaust hose, and a shaft, called spring shaft,
which is driven by a spring for winding in the exhaust hose. This second aspect is
characterised in that the rack arm comprises a spring housing for receiving said spring.
[0037] Accordingly, the second aspect is based on the idea of using a rack arm having an
integrated spring housing, instead of using one or more separate spring cassettes.
Although such a construction is particularly advantageous for use in combination with
the downshift concept described above, this second aspect can be generally used also
without downshift. Consequently, said second aspect can be implemented also in direct
drive exhaust hose reeling devices.
[0038] In a particularly preferred embodiment of this second aspect, the spring housing
is made in one piece with the rack arm. This can be achieved, for example, by the
spring housing having an essentially cylindrical circumferential wall and an essentially
circular bottom wall, said walls being made in one piece with the rest of the rack
arm. The spring housing can also be integrated with the rack arm without being made
in one piece therewith.
[0039] Preferably, the rack arm can be made by injection moulding of a polymer material
or die-casting of an aluminium material.
[0040] The overall construction can be made very compact, particularly in the axial direction
with reference to the axis of rotation of the drum. More particularly, the spring
housing can be at least partially recessed in the rack arm.
[0041] According to a third aspect, an exhaust hose reeling device is provided, comprising
an exhaust hose, a rotatably mounted drum for winding in and reeling out the exhaust
hose, and a shaft, called spring shaft, which is driven by a spring for winding in
the exhaust hose. This third aspect is characterised in that the spring shaft is eccentrically
arranged relative to the axis of rotation of the drum. This aspect also allows designing
of an exhaust hose reeling device of small axial dimensions. It can be implemented
without the use of a downshift transmission.
[0042] According to a fourth aspect, an exhaust hose reeling device is provided, comprising
an exhaust hose, a rotatably mounted drum for winding in and reeling out the exhaust
hose, and a shaft, called spring shaft, which is driven by a coil spring for winding
in the exhaust hose. This fourth aspect is characterised in that the spring shaft
is eccentrically arranged relative to the coil spring.
[0043] Eccentrically arranged here refers to the relationship between the spring shaft and
an imaginary centre of the essentially circular outer circumference of the spring.
[0044] Such a construction can be generally used for mounting coil springs for reeling devices,
including devices without downshift and without integrated spring housings.
[0045] The advantage of such a construction is that the turns of the spring are effectively
separated from each other, which facilitates the relative motion of the turns and
results in less friction and better overall performance of the spring. This aspect
can be used to reduce the spring dimensions.
[0046] According to a fifth aspect, an exhaust hose reeling device is provided, comprising
a rack arm, an exhaust hose, a drum which is rotatably mounted in the rack arm for
winding in and reeling out the exhaust hose, and a spring for winding in the exhaust
hose. This fifth aspect is characterised in that the rack arm is made of a material
comprising at least one of a polymer material and an aluminium material. Accordingly,
such a rack arm can be made by injection moulding of a polymer material or die-casting
of an aluminium material. This aspect can be used not only in combination with downshift
and integrated spring housings, but also in conventional direct drive exhaust hose
reeling devices with separate spring cassettes.
[0047] According to a sixth aspect, a method of manufacturing an exhaust hose reeling device
of the kind comprising a rack arm, an exhaust hose, a drum which is rotatably mounted
in the rack arm for winding in and reeling out the exhaust hose, and a coil spring
for winding in the exhaust hose. The method is characterised by the steps of forming
said rack arm in one piece with a spring housing, mounting a continuous drive shaft
in a bottom wall of the spring housing, and applying the coil spring in the spring
housing, in connection with which an inner end of the coil spring is connected to
said drive shaft.
[0048] According to a seventh aspect, an exhaust hose reeling device is provided, comprising
an exhaust hose, a rotatably mounted drum for winding in and reeling out the exhaust
hose, spring means for driving the drum in the winding-in direction, and ratchet means
for preventing the exhaust hose from being unintentionally wound in when it is in
a pulled-out state and the spring means is tensioned, which spring means comprises
a ratchet rim, which rotates with the drum and has a plurality of ratchet teeth distributed
along its circumference. The reeling device according to the seventh aspect is characterised
by a gear rim, which is driven by the spring means and rotates with the drum for driving
thereof and which is located at least partially in the same radial plane as the ratchet
rim.
[0049] One particular advantage of a reeling device according to this aspect is that, owing
to the fact that the driving gear rim and the ratchet teeth are arranged at least
partially in a common radial plane, it can have small axial dimensions with reference
to the axis of rotation of the drum.
[0050] A further advantage is that the location of the gear rim and the ratchet rim allows
them to be made in one piece with one another and/or in one piece with an end wall
of the drum. This in turn gives considerable advantages in terms of both reliability
in operation and manufacturing costs.
[0051] According to this aspect, the gear rim can preferably have the form of an internal
gear rim with gear teeth that are turned radially inward and can further be located
radially inside the ratchet rim.
[0052] The common radial plane can preferably be located between the drum and a rack arm
of the reeling device which supports the drum.
[0053] According to the seventh aspect, the gear rim and the ratchet rim can be made in
one piece with one another. In particular, they can be made in one piece with an end
wall of the drum. This allows efficient manufacture and effective protection against
the hose being unintentionally wound in.
[0054] Said end wall, the ratchet rim and the gear rim can be made in one piece, preferably
by injection moulding, of a polymer material. They can also be made in one piece,
preferably by die-casting, of an aluminium material.
[0055] Said end piece can be made in one piece with a shaft journal for rotatable mounting
of the drum.
[0056] In one embodiment according to this aspect, the reeling device can further comprise
a plurality of axially open locking compartments, which are distributed along the
circumference, said locking compartments being arranged radially between the ratchet
rim and the gear rim and adapted to receive a locking pin for temporarily locking
the drum to prevent it from rotating. Such locking compartments can be limited along
the circumference by essentially radially extending wall elements made in one piece
with the ratchet rim and the gear rim.
[0057] In a particularly preferred embodiment according to this aspect, the exhaust hose
reeling device has a speed-downshift transmission.
[0058] In one embodiment of the seventh aspect, the spring means can comprise at least one
coil spring.
[0059] It will be appreciated that the aspects described above can be combined in a number
of ways and that the aspects can be used independently of each other to obtain the
above-mentioned and other advantages.
Brief Description of the Drawings
[0060] The invention will now be described in more detail by means of a non-limiting embodiment
and with reference to the accompanying drawings.
[0061] Fig. 1 is a perspective view of an embodiment of an exhaust hose reeling device.
[0062] Fig. 2 is an exploded view of part of the reeling device in Fig. 1.
[0063] Fig. 3 is a perspective view of parts of an evacuation side of the reeling device
in Fig. 1.
[0064] Fig. 4 is a perspective front view of a rack arm of the reeling device in Fig. 1.
[0065] Fig. 5 is a cross-sectional view of the rack arm in Fig. 4.
[0066] Fig. 6 is a perspective view of an outer side of the rack arm in Fig. 4 with drive
means mounted therein.
[0067] Fig. 7 is a perspective view of an inner side of the rack arm in Fig. 4 with a gear
drive mounted therein.
[0068] Fig. 8 is a cross-sectional view of the rack arm shown in Fig. 6 and Fig. 7.
[0069] Fig. 9 illustrates a combined setting and releasing device.
[0070] Fig. 10 is a perspective view of a drum end wall of the reeling device in Fig. 1
and also shows, in enlarged scale, parts of a gear rim and a ratchet rim.
[0071] Fig. 11 is a cross-sectional view of the drum end wall in Fig. 10.
[0072] Fig. 12 shows the drum end wall in Fig. 8 in engagement with the gear wheel driven
by the spring.
[0073] Figs 13-15 illustrate the different operating positions of a ratchet mechanism.
[0074] Fig. 16 is a plan view of an embodiment of a drum end wall with an integrated spring
housing.
Description of a preferred embodiment
[0075] In Figs 1-3, reference numeral 1 generally designates an exhaust hose reeling device
for winding in an exhaust hose 2, which is indicated schematically by a dashed line
in Fig. 1 and which is designed for extraction of exhaust gases from the tail pipe
of a vehicle. For this purpose, the reeling device 1 is adapted to be connected to
a suction device (not shown).
[0076] The exhaust hose reeling device 1 comprises as its main components - besides the
exhaust hose 2 - a rack 3, a drum 5 which is rotatably mounted in the rack 3 and drive
means for driving the drum 5 at least in one winding-in direction B.
[0077] The rack 3 is essentially U-shaped and comprises two mounting sections 7 for suspending
the rack 3 from the ceiling or mounting it on a wall, and two rack arms which project
from the mounting sections 7 and support the drum 5 between them. The rack arm on
the driving side of the reeling device 1 (Figs 1 and 2) comprises two sections 11
and a supporting unit 13 mounted thereon. The rack arm on the evacuation side of the
reeling device 1 (Fig. 3) also comprises two sections 15 and a supporting unit 17
mounted thereon. In the example shown, the sections 7, 11 and 15 are made of metal
and welded together to form a U, as illustrated in the figure, while the supporting
units 13 and 17 are made of a polymer material, such as an injection-moulded polymer
material. The supporting units 13 and 17 can be made, for example, of polyamide, polypropylene,
polyester or any other suitable structural plastic. Reference numeral 9 designates
fittings for mounting the rack 3.
[0078] The supporting units 13 and 17 are each provided with two elongate spaces 19 for
receiving the sections 11 and 15, respectively, and mounting holes 21 corresponding
to mounting holes 23 in the sections 11/15.
[0079] The supporting unit 13 on the drive side of the reeling device will now be described
in more detail with reference to Figs 4-8. The main functions of the supporting unit
13 are to support the drum together with the other unit 17 and to support parts of
the driving device, as will be described below.
[0080] The unit 13 has a spring-receiving space 31, called spring housing, which is open
on the side oriented toward the outer side of the unit 13 (i.e. the side facing away
from the drum 5) for receiving at least one coil spring 41. The spring housing 31
is defined by an essentially cylindrical, circumferential wall 33 and a bottom wall
35, which are both made in one piece with the rest of the unit 13. In the embodiment
shown, the spring housing 31 is thus both integrated with the unit 13 and recessed
therein.
[0081] The exploded view in Fig. 2 shows the coil spring 41 before mounting, while Fig.
6 and Fig. 8 show the coil spring 41 in the mounted state in the spring housing 31.
The construction is such that the coil spring 41 is tensioned when the exhaust hose
is pulled out from the drum 5 in the reeling-out direction A, so that the coil spring
41 can drive the drum 5 in the winding-in direction B allowing the hose 2 to be wound
onto the drum 5.
[0082] The spring housing 31 is provided with means which engages the outer end 43 of the
spring 41 to form an abutment when the spring 41 is tensioned. In the embodiment shown,
said engagement means is a specially designed recess 45 in the circumferential wall
33 of the spring housing 31. The recess 45 has opposite undercut edges 47, and the
outer end 43 of the coil spring 41 is shaped in such manner that it engages one of
said edges 47, depending on the orientation of the mounted spring. Thus, this design
is advantageous since it allows easy mounting 41 of the spring in an optional position
depending on the desired winding-in direction of the drum 5, while the engagement
as such is easily achieved by inserting the spring 41 in the spring housing 31.
[0083] The bottom wall 35 of the spring housing 31 is provided with a through opening 51
(Fig. 4) intended for a shaft 53, called spring shaft, which is driven by the spring
41 and which has an inner end 54 that is located in the spring housing 31 and an outer
end 56 that is located on the inner side of the supporting unit 13, as shown in Fig.
8. The spring shaft 53 is rotatably mounted in the opening 51 by means of a ball bearing
62 fitted in the opening 51 (Figs 2 and 8). The inner end 54 of the spring shaft 53
has a radial engagement edge 55, as shown in Fig. 6, for engaging the inner end of
the spring 41. Reference numeral 57 designates a hexagonal hole for manually adjusting
the winding-in moment of force, as will be described in more detail below.
[0084] The outer end 56 of the spring shaft 53 is drivingly connected to a gear wheel 59.
In the embodiment shown, the gear wheel 59 is concentrically mounted on the spring
shaft 53. Moreover, in this embodiment, the gear wheel 59 is operatingly connected
to the spring shaft 53 by means of a special setting and releasing device, generally
designated 61, the function of which will be described below. The device 61, which
is shown in detail in Fig. 9, comprises a locking pin 63 which is provided with a
bevelled outer end and which is radially displaceable back and forth in the outer
end 56 of the spring shaft 53. The locking pin 63 engages in one of three corresponding
bevelled locking grooves 65 of the gear wheel 59. A resilient means 64, such as a
rubber element, exerts a radially outward force on the locking pin 63. The device
61 is covered by a lid 60, as shown in Fig. 7.
[0085] During normal operation (winding in/reeling out), the locking pin 63 engages in one
of the three locking grooves 65, as shown in Fig. 9, the device 61 acting as a torsionally
rigid or fixed connection, which prevents any undesired relative rotation between
the spring shaft 53 and the gear wheel 59. More specifically, when the hose is reeled
out and the gear wheel 53 thus driven in direction A, a force is exerted on the locking
pin 63 by the radial edge designated 67 in Fig. 9 for transmitting a spring-tensioning
moment of force to the spring shaft 53. On the other hand, when the exhaust hose 2
is to be wound in, the spring 41 drives the spring shaft 53 in direction B in Fig.
8, the locking pin 63 transmitting the driving torque to the gear wheel 59 through
the edge 67.
[0086] As indicated at E2 in Fig. 5, the opening 51 for the spring shaft 53 is eccentrically
arranged relative to the spring housing 31 (i.e. relative to the essentially circular
outer circumference of the spring 41), the dashed line L1 in Fig. 5 representing the
symmetry axis of the cylindrical spring housing 31 and the dash and dot line L2 representing
the axis of rotation of the spring shaft 53. This offset E2 creates "asymmetry" in
the turns of the spring, which effectively prevents adjoining turns of the coil spring
41 from interlocking in an undesired manner due to friction and/or adhesion. This
allows a more efficient and balanced operation of the spring 41. In a simpler variant,
the axes L1 and L2 may coincide.
[0087] As shown in Fig. 6 and also in the exploded view in Fig. 2, the spring 41 is mounted
in the spring housing 31, and then a circular plate 66 having a centre hole that corresponds
to the inner end 54 of the spring shaft 53 is placed over the innermost turns of the
spring. The spring 41 is then secured to the spring housing 31 by means of a locking
element 68, and, eventually, a lid 72 is screwed onto the unit 13 to cover the spring
housing 31. Reference numeral 74 designates four grooves that are formed in the circumferential
wall 33 and the bottom wall 35 of the spring housing 31 for facilitating removal of
the spring 41. To remove the spring 41, any suitable flexible means can be inserted
through each such groove 74 and passed round the outermost turns of the spring to
allow the spring 41 to be taken out.
[0088] The drum 5 and the driving thereof will be described in more detail below with reference
to Figs 1-3 and Figs 10-12.
[0089] The drum 5 comprises two opposite end walls 71, 73, which are mounted in the supporting
units 13 and 17, respectively, of the rack 3. The drum 5 further comprises a tubular
means 75, which connects the end walls 71, 73 with one another. In the embodiment
shown, the tubular means 75 is made of a metal sheet that is bent to a cylindrical
shape and attached by screwing to the inside of the end walls 71, 73.
[0090] Preferably, the drum 5 is intended for winding the exhaust hose 2 onto the tubular
means 75 and unwinding it therefrom in only one hose layer, as opposed to smaller
and lighter reeling devices, for example, for supply cables, such as electric cables
and compressed-air hoses, which are wound in several layers.
[0091] One end of the exhaust hose 2 is connected to a pipe socket 79 (Fig. 3), which is
connected to a central opening 80 in the drum end wall 73. The opening 80 is in turn
rotatably connected to a non-rotating pipe-coupling 83 formed in the supporting rack
unit 17 and adapted to be connected to a suction device (not shown).
[0092] In the embodiment shown, driving of the drum 5 is effected on the drum end wall 71
supported by the supporting rack unit 13. The supporting unit 12 has an opening 81
in which a ball bearing 83 is provided for rotatably carrying a shaft journal 85 of
the drum end wall 71. In the embodiment shown, the drum end wall 71 - like the supporting
units 13 and 17 - is made in one piece of, for example, an injection-moulded polymer
material, thus allowing the shaft journal 85 to be made in one piece with the drum
end wall 71. In general, the same material options are available for the integrally
formed drum end walls 71 and 73 as for the integrally formed rack units 13 and 17.
[0093] The drum end wall 71 is made in one piece with a ratchet rim 91, which has a plurality
of external, inclined ratchet teeth as well as two "free" portions 92 without such
ratchet teeth. The drum end wall 71 is further made in one piece with an internal
gear rim 93, which in this embodiment is arranged radially inside the ratchet rim
91.
[0094] The function of the ratchet rim 91 is to prevent, in per se known manner, the hose
2 from being unintentionally wound in (direction B) when it is in use and pulled out
to varying degrees.
[0095] In the locked position according to Fig. 13, a ratchet pawl 94 engages the ratchet
teeth of the ratchet rim 91 in such manner that the drum 5 is prevented from rotating
in the reeling-out direction B, but allowed to rotate in the winding-in direction
A as the ratchet pawl 94 moves over the ratchet teeth.
[0096] To release the ratchet mechanism, the user pulls out the hose 2 far enough in the
reeling-out direction A for the ratchet pawl 94 to reach one of the free portions
92, as shown in Fig. 14. The hose 2 is then released and the tensioned spring 41 can
drive the drum 5 in the winding-in direction B according to Fig. 15.
[0097] The internal gear rim 93, which is made in one piece with the drum end wall 71 and,
thus, torsionally rigidly connected to the drum 5, engages the gear wheel 59, as shown
schematically in Fig. 12. The gear wheel 59 connected to the spring shaft 53 and the
internal gear rim 93 of the drum end wall 71 together form a downshift transmission.
Unlike prior-art direct drive reeling devices, the axis of rotation L2 of the spring
shaft 53 is eccentric relative to the axis of rotation L3 of the drum 5, as indicated
by E2 in Fig. 5.
[0098] Owing to the downshift transmission, the speed of the spring shaft 53 is higher than
the speed of the drum 5 and the driving torque of the spring shaft 53 is correspondingly
upshifted during winding-in. In the embodiment shown, the gear ratio is about 5:1,
but it can be varied significantly. Thus, gear ratios ranging from, for example, 2:1
to 10:1 are conceivable.
[0099] As described above, the downshift transmission gives several advantages in applications
which traditionally would require heavy-duty coil springs and, in many cases, the
use of more than one such spring.
[0100] By using a speed-downshift transmission between the spring shaft 53 and the drum
5, the required winding-in moment of force can be obtained using considerably smaller
and lighter springs than was previously possible and, in most applications, one coil
spring will be enough, even for relatively heavy/long hoses. Accordingly, the spring
41 can be dimensioned in such manner that, in an imaginary construction without downshift
and a speed ratio of 1:1, it would not allow the whole exhaust hose to be wound in.
[0101] Using smaller and weaker springs is advantageous in several ways in terms of manufacturing
costs, handling safety and choice of material for the surrounding structures. In particular,
the use of weaker springs allows weaker, and thus less expensive, constructions in
the spring housing/spring cassette. Thus, integration of the spring housing in the
supporting unit 13 is considerably facilitated, while at the same time the whole unit
can be made of a weaker material, such as a polymer material, than traditional sheet-metal
constructions.
[0102] As a non-limiting example, which illustrates the effect of the downshift transmission,
it may be noted that the applicant behind the present invention has marketed exhaust
hose reeling devices having three springs arranged in two spring cassettes connected
in parallel, each coil spring, in the tensioned state, having the ability to exert
a torque of about 25 Nm, which gives a total torque of about 75 Nm. Tests have shown
that a speed ratio of about 1:5 for the downshift transmission allows said three coil
springs of 25 Nm to be reduced to only one smaller coil spring of about 15 Nm and
the spring thickness to be reduced from 1.5 mm to 1.1 mm.
[0103] The possibility of using weaker springs is not the only advantage of the downshift
transmission. It also allows a considerably improved and more accurate setting of
the winding-in moment of force than without downshift. In prior-art exhaust hose reeling
devices, the winding-in moment of force is traditionally changed by changing the number
of complete hose windings on the drum.
[0104] In the present example, the winding-in moment of force acting on the drum 5 can be
set using the setting device shown in Fig. 9. For instance, to slightly increase the
winding-in moment of force on the drum 5 for the purpose of balancing the reeling
device 1, the spring shaft 53 is rotated by means of a tool (not shown) which is inserted
in the hexagonal hole 57 in the shaft end 54 (Fig. 6). To this end, the lid 72 is
formed with an access hole 74 (Fig. 1).
[0105] If the drum 5 is kept in the locked position (see below), the gear wheel 59 being
thus also locked, the spring shaft 53 can be rotated in the direction of the arrow
A in Fig. 9. The locking pin 63 will then be pushed out of its engagement position
and move towards the next locking groove 65 while the spring 41 is being tensioned.
It will be appreciated that with a gear ratio of 5:1 and with three locking grooves
65, the setting resolution for the moment of force is 5 * 3 = 15 times finer than
in prior-art solutions, i.e. it takes 15 "clicks" of the setting device to increase
the winding-in moment of force so that it corresponds to one complete hose winding.
[0106] It should be noted that the device shown in Fig. 9 does not serve exclusively as
a setting device. It also protects the spring 41 in the event that someone manually
rotates the drum 5 in the winding-in direction when the exhaust hose 2 is completely
wound in. In this situation, the gear rim 93 will drive the gear wheel 59 in the direction
of the arrow B in Fig. 9. The locking pin 63 will then be pushed out of the locking
groove 65, thereby preventing undesired backward turning of the spring 41. In this
state, the device 61 thus acts as an automatic releasing device.
[0107] The ratchet rim 91 and the gear rim 93 define between them a plurality of locking
compartments 95 distributed along the circumference. More specifically, an number
of inclined transverse walls 96 are provided between the ratchet rim 91 and the gear
rim 93, which transverse walls 96 serve both as partition walls between adjoining
locking compartments and as stabilising elements for the ratchet rim 91 and the gear
rim 93. In the embodiment shown, the transverse walls 96 are also made in one piece
with the end wall 71.
[0108] The locking compartments 95 are adapted to cooperate with a locking pin 97, which
is reciprocable in a hole 99 in the supporting rack unit 13. When the locking pin
97 is inserted in a locking compartment 95, it effectively prevents the drum 5 from
rotating in an undesired manner. This is of use, for example, in connection with maintenance
and transport. The large number of locking compartments 95 provided along the circumference
facilitates locking of the drum. If the end wall 71, as is the case here, is provided
with locking compartments 95 along its entire circumference, the drum 5 can be manually
locked in essentially any rotary position.
[0109] As is best illustrated in Fig. 11, the drum end wall 71 in the example shown has
very compact axial dimensions and the ratchet rim 91, the gear rim 93 and the locking
compartments 95 as well as the shaft journal 85 are located at least partially in
essentially the same radial plane.
[0110] The drum end wall 71 shown in Figs 10 and 11 has several advantages:
- The drum end wall 71 is compact in the axial direction because the ratchet rim 91,
the gear rim 93 and the locking compartments 95 are located at least partially in
the same radial plane. This makes the reeling device 1 as a whole axially compact.
Furthermore, the distance between the drum end wall 71 and the supporting unit 13
is advantageously reduced.
- The construction shown allows the internal gear rim 93 to be positioned far out in
the radial direction, which allows for a larger gear rim and, thus, the possibility
of using even weaker springs.
- Owing to the integrated design, the ratchet rim 91 and the locking compartments 95,
which both act to prevent unintentional rotation of the drum 5, are securely connected
to the drum 5, thus effectively preventing any unintentional rotary motion between
on the one hand the ratchet rim/locking compartment and, on the other, the drum end
wall 71.
The gear rim 93 is also effectively prevented from rotating relative to the rest of
the drum 5 by virtue of its integrated design, which, in addition, is obtained by
means of a simple and inexpensive manufacturing process.
It will be appreciated that a person skilled in the art can modify the exhaust hose
reeling device described above in various ways and still exploit the advantages of
the different partial solutions.
The following are examples of conceivable modifications/variants.
- The rack 3 can be designed to have only one rack arm 13, the drum 5 being mounted
in a single bearing.
- The supporting rack units 13 and 15 can comprise materials other than a polymer material.
They may, for example, be moulded or cast in one piece of aluminium.
- More than one spring can be provided in the spring housing 41.
- The spring housing can be arranged on the inside of the rack arm, i.e. closest to
the drum.
- The downshift transmission can be used in combination with traditional spring cassettes,
i.e. without an integrated spring housing 31.
- Optionally, the spring 41 can be mounted in a separate spring cassette, which is then
inserted in the spring housing/recess 31 of the rack arm 13. Such a spring cassette
may facilitate handling of the spring. If downshift is used, the spring 41 can be
weaker and, thus, a lighter construction of such a spring cassette can be used than
has previously been possible.
- The downshift transmission can be used in combination with traditional metal racks,
i.e. without the integrally formed rack units 13/15.
- The integrated spring housing 31 and/or the integrally formed supporting unit 13 can
be used also without a downshift transmission.
- Both drum end walls can be subjected to driving.
- The downshift transmission can be achieved in other ways. For instance, the internal
gear rim can be replaced by a gear wheel having an outer row of teeth, which is driven
by the gear wheel connected to the spring. Moreover, the ratchet rim 91 can be arranged
radially inside the gear rim 93.
- The gear transmission 59/93 can comprise further gear drives.
- In a simpler construction, the gear wheel 59 can be fixedly attached to the spring
shaft 53, which means that the setting and safety device 61 can be omitted.
- The transmission can comprise a belt drive or a chain drive, although the gear transmission
shown is currently preferred.
- The construction can be modified so that the gear ratio of the downshift transmission
varies as a function of the length of hose pulled out.
- Each of the ratchet rim 91, the gear rim 93 and the locking compartments 95 can be
carried out independently of the drum end wall 71. As an example, the ratchet rim
91, the gear rim 93 and the transverse walls 96 with the intermediate locking compartments
95 can be manufactured as a separate combined ratchet and drive wheel, optionally
of an injection-moulded polymer material or a die-cast aluminium material. Such a
combined ratchet and drive wheel can then be mounted as a separate unit on the drum.
- The ratchet rim 91 and/or locking compartments 95 can alternatively be arranged at
the opposite drum end wall 73.
[0111] Finally, reference is made to Fig. 16, which illustrates an alternative embodiment.
Fig. 16 shows a drum end wall 117 which is provided with a ratchet rim 191 and locking
compartments 195 corresponding to the ratchet rim 91 and the locking compartments
95 in the embodiment shown above. However, the drum end wall 117 in Fig. 16 has no
internal gear rim. Instead, the drum end wall 117 is adapted to be used in a direct
drive embodiment, i.e. without a speed-downshift transmission.
[0112] The drum end wall 117 is preferably made of an injection-moulded polymer material,
alternatively a die-cast aluminium material, and has a spring housing 131, preferably
made in one piece with the drum end wall 117, for receiving at least one coil spring
141. The outer end of the coil spring 141 engages, in the same way as in the previous
embodiment, in a recess 145 in the circumferential wall of the spring housing 131.
The inner end 142 of the coil spring 141 drives a shaft that is concentric with the
axis of rotation of the drum 5.
[0113] This embodiment has the same advantages in terms of manufacture as the previously
shown embodiment as regards the integration of the spring housing 31 in the rack arm
13.
1. An exhaust hose reeling device (1), comprising an exhaust hose (2), a rotatably mounted
drum (5) for winding in and reeling out the exhaust hose (2), and a shaft (53), called
spring shaft (53), which is driven by at least one spring means (41) adapted to wind
in the exhaust hose (2) and having an inner end and an outer end (43), the inner end
of the spring means (41) being connected to the spring shaft (53) and the spring means
(41) comprising least one coil spring (41), characterised in that the reeling device is such that a downshift occurs, at least when the exhaust hose
(2) is wound in, which is such that the speed of the spring shaft (53), relative to
the outer end (43) of the spring means (41) is higher than the speed of the drum (5),
that the reeling device further comprises a downshift transmission means (59/93) comprising
a downshift gear transmission (59/93) for performing said downshift, wherein said
downshift gear transmission (59/93) comprises a gear wheel (59), which is driven by
the spring shaft (53), and an internal gear rim (93), which is driven by said gear
wheel (59).
2. A reeling device according to claim 1, wherein the gear wheel (59) is mounted on the
spring shaft (53).
3. A reeling device according to claim 1 or 2, wherein the internal gear rim (93) is
concentric with the drum (5).
4. A reeling device according to any one of claims 1-3, wherein the internal gear rim
(93) is mounted on the outside of a drum end wall (71).
5. A reeling device according to claim 4, wherein the internal gear rim (93) is made
in one piece with said drum end wall (71).
6. A reeling device according to claim 5, wherein the internal gear rim (93) and said
drum end wall (71) are made in one piece of a material comprising at least one of
a polymer material and an aluminium material.
7. A reeling device according to any one of the preceding claims, wherein the spring
means (41) is dimensioned in such manner that, in an imaginary direct drive construction
without said downshift, it would not allow the hose to be wound in.
8. A reeling device according to any one of the preceding claims, wherein the spring
means (41) is dimensioned in such manner that it exerts a moment of force on the spring
shaft (53) not exceeding 20 Nm, preferably not exceeding 15 Nm.
9. A reeling device according to any one of the preceding claims, further comprising
a rack arm (13), which supports the drum (5) and which is formed with a space (31),
called spring housing, for receiving said spring means (41).
10. A reeling device according to claim 9, wherein the spring housing (31) of the rack
arm (13) is formed by an essentially cylindrical circumferential wall (33) and a bottom
wall (35).
11. A reeling device according to claim 10, wherein the circumferential wall (33) and
the bottom wall (35) of the spring housing (31) are made in one piece with the rack
arm (13).
12. A reeling device according to any one of claims 9-11, wherein the rack arm (13) is
made of a material comprising at least one of a polymer material and an aluminium
material.
13. A reeling device according to any one of claims 9-12, wherein the spring shaft (53)
is extended through an opening (51) in the bottom wall (35) of the spring housing
(31).
14. A reeling device according to any one of claims 9-13, wherein the spring housing (31)
is at least partially recessed in the rack arm (13).
15. A reeling device according to any one of the preceding claims, wherein the spring
shaft (53) is eccentrically arranged relative to the axis of rotation (L3) of the
drum (5).
16. A reeling device according to any one of the preceding claims, wherein the spring
means (41) comprises at least one coil spring (41) and wherein the spring shaft (53)
is eccentrically arranged relative to the coil spring (41).
1. Abgasschlauchaufwickelvorrichtung (1), die einen Abgasschlauch (2), eine drehbar montierte
Trommel (5) für das Aufwickeln und Auswickeln des Abgasschlauches (2) und einen durch
mindestens eine Federeinrichtung (41) angetriebenen Schaft (53), Federschaft (53)
genannt, die zum Aufwickeln des Abgasschlauches (2) angepasst ist und ein inneres
Ende und ein äußeres Ende (43) besitzt, wobei das innere Ende der Federeinrichtung(41)
mit dem Federschaft (53) verbunden ist, umfasst und wobei die Federeinrichtung (41)
mindestens eine Schraubenfeder (41) umfasst,
dadurch gekennzeichnet, dass
die Aufwickelvorrichtung so ausgelegt ist, dass eine Verlangsamung wenigstens dann
stattfindet, wenn der Abgasschlauch (2) aufgewickelt ist, welche so ausgelegt ist,
dass die Geschwindigkeit des Federschaftes (53) hinsichtlich des äußeren Endes (43)
der Federeinrichtung (41) höher ist als die Geschwindigkeit der Trommel (5), dass
die Aufwickelvorrichtung außerdem eine Verlangsamungsübertragungseinrichtung (59/93)
umfasst, die eine Herunterschaltübertragung(59/93) zum Durchführen der Verlangsamung
umfasst, wobei die Herunterschaltübertragung (59/93) ein durch den Federschaft (53)
angetriebenes Getrieberad (59) und einen durch das Getrieberad (59) angetriebenen
inneren Zahnkranz (93) umfasst.
2. Aufwickelvorrichtung gemäß Anspruch 1, wobei das Getrieberad (59) auf dem Federschaft
(53) montiert ist.
3. Aufwickelvorrichtung gemäß Anspruch 1 oder 2, wobei der innere Zahnkranz (93) mit
der Trommel (5) konzentrisch ist.
4. Aufwickelvorrichtung gemäß einem der Ansprüche 1-3, wobei der innere Zahnkranz (93)
auf der Außenseite einer Trommelendwand (71) montiert ist.
5. Aufwickelvorrichtung gemäß Anspruch 4, wobei der innere Zahnkranz (93) einstückig
mit der Trommelendwand (71) hergestellt ist.
6. Aufwickelvorrichtung gemäß Anspruch 5, wobei der innere Zahnkranz (93) und die Trommelendwand
(71) einstückig aus einem Material hergestellt sind, das mindestens eines von einem
Polymermaterial und einem Aluminiummaterial umfasst.
7. Aufwickelvorrichtung gemäß einem der vorhergehenden Ansprüche, wobei die Federeinrichtung
(41) derart dimensioniert ist, dass in einer imaginären direkten Betriebskonstruktion
ohne die Verlangsamung, diese ein Aufwickeln des Schlauches nicht erlauben würde.
8. Aufwickelvorrichtung gemäß einem der vorhergehenden Ansprüche, wobei die Federeinrichtung
(41) derart dimensioniert ist, dass sie ein Kraftmoment auf den Federschaft (53) ausübt,
das 20 Nm vorzugsweise 15 Nm nicht übersteigt.
9. Aufwickelvorrichtung gemäß einem der vorhergehenden Ansprüche, die außerdem einen
Gestellarm (13) umfasst, welcher die Trommel (15) trägt und welcher mit einem Raum
(31), Federgehäuse genannt, zum Empfangen der Federeinrichtung (41) gebildet ist.
10. Aufwickelvorrichtung gemäß Anspruch 9, wobei das Federgehäuse (31) des Gestellarmes
(13) durch eine im wesentlichen zylindrisch umlaufende Wand (33) und eine Bodenwand
(35) gebildet ist.
11. Aufwickelvorrichtung gemäß Anspruch 10, wobei die umlaufende Wand (33) und die Bodenwand
(35) des Federgehäuses (31) einstückig mit dem Gestellarm (13) hergestellt sind.
12. Aufwickelvorrichtung gemäß einem der Ansprüche 9-11, wobei der Gestellarm (13) aus
einem Material hergestellt ist, das mindestens eines von einem Polymermaterial und
einem Aluminiummaterial umfasst.
13. Aufwickelvorrichtung gemäß einem der Ansprüche 9-12, wobei sich der Federschaft (53)
durch eine Öffnung (51) in der Bodenwand (35) des Federgehäuses (31) erstreckt.
14. Aufwickelvorrichtung gemäß einem der Ansprüche 9-13, wobei das Federgehäuse (31) mindestens
teilweise in den Gestellarm (13) eingelassen ist.
15. Aufwickelvorrichtung gemäß einem der vorhergehenden Ansprüche, wobei der Federschaft
(53) exzentrisch relativ zu der Rotationsachse (L3) der Trommel (5) angeordnet ist.
16. Aufwickelvorrichtung gemäß einem der vorhergehenden Ansprüche, wobei die Federeinrichtung
(41) mindestens eine Schraubenfeder (41) umfasst und wobei der Federschaft (53) exzentrisch
relativ zu der Schraubenfeder (41) angeordnet ist.
1. Dispositif d'enroulement (1) de tuyau d'échappement, comprenant un tuyau d'échappement
(2), un tambour monté de manière rotative (5) destiné à enrouler et à dérouler le
tuyau d'échappement (2), et un arbre (53), appelé arbre de ressort (53), qui est entraîné
par au moins un moyen de ressort (41) adapté pour enrouler le tuyau d'échappement
(2) et ayant une extrémité intérieure et une extrémité extérieure (43), l'extrémité
intérieure du moyen de ressort (41) étant reliée à l'arbre de ressort (53) et le moyen
de ressort (41) comprenant au moins un ressort hélicoïdal (41), caractérisé en ce que le dispositif d'enroulement est tel qu'une rétrogradation survient, au moins lorsque
le tuyau d'échappement (2) est enroulé, qui est telle que la vitesse de l'arbre de
ressort (43) par rapport à l'extrémité extérieure (43) du moyen de ressort (41) est
supérieure à la vitesse du tambour (5), en ce que le dispositif d'enroulement comprend en outre un moyen de transmission de rétrogradation
(59/93) comprenant une transmission à engrenage de rétrogradation (59/93) pour effectuer
ladite rétrogradation, dans lequel ladite transmission à engrenage de rétrogradation
(59/93) comprend une roue dentée (59), laquelle est entraînée par l'arbre de ressort
(53), et une jante dentée interne (93), qui est entraînée par ladite roue dentée (59).
2. Dispositif d'enroulement selon la revendication 1, dans lequel la roue dentée (59)
est montée sur l'arbre de ressort (53).
3. Dispositif d'enroulement selon la revendication 1 ou 2, dans lequel la jante dentée
interne (93) est concentrique avec le tambour (5).
4. Dispositif d'enroulement selon l'une quelconque des revendications 1 à 3, dans lequel
la jante dentée interne (93) est montée sur l'extérieur de la paroi d'extrémité de
tambour (71).
5. Dispositif d'enroulement selon la revendication 4, dans lequel la jante dentée interne
(93) est composée d'un seul tenant avec ladite paroi d'extrémité de tambour (71).
6. Dispositif d'enroulement selon la revendication 5, dans lequel la jante dentée interne
(93) et ladite paroi d'extrémité de tambour (71) sont composées d'un seul tenant d'un
matériau comprenant au moins un matériau parmi un matériau polymère et un matériau
aluminium.
7. Dispositif d'enroulement selon l'une quelconque des revendications précédentes, dans
lequel le moyen de ressort (41) est dimensionné d'une manière telle que, dans une
construction d'entraînement direct imaginaire sans ladite rétrogradation, il ne permet
pas au tuyau d'être enroulé.
8. Dispositif d'enroulement selon l'une quelconque des revendications précédentes, dans
lequel le moyen de ressort (41) est dimensionné d'une manière telle qu'il exerce un
moment de force sur l'arbre de ressort (53) ne dépassant pas 20 Nm, de préférence
ne dépassant pas 15 Nm.
9. Dispositif d'enroulement selon l'une quelconque des revendications précédentes, comprenant
en outre un bras de crémaillère (13), qui supporte le tambour (5) et qui est formé
avec un espace (31), appelé logement de ressort, destiné à recevoir ledit moyen de
ressort (41).
10. Dispositif d'enroulement selon la revendication 9, dans lequel le logement de ressort
(31) du bras de crémaillère (13) est formé par une paroi circonférentielle essentiellement
cylindrique (33) et une paroi inférieure (35).
11. Dispositif d'enroulement selon la revendication 10, dans lequel la paroi circonférentielle
(33) et la paroi inférieure (35) du logement de ressort (31) sont composées d'un seul
tenant avec le bras de crémaillère (13).
12. Dispositif d'enroulement selon l'une quelconque des revendications 9 à 11, dans lequel
le bras de crémaillère (13) est composé d'un matériau comprenant au moins l'un parmi
un matériau polymère et un matériau aluminium.
13. Dispositif d'enroulement selon l'une quelconque des revendications 9 à 12, dans lequel
l'arbre de ressort (53) est étendu à travers une ouverture (51) dans la paroi inférieure
(35) du logement de ressort (31).
14. Dispositif d'enroulement selon l'une quelconque des revendications 9 à 13, dans lequel
le logement de ressort (31) est au moins partiellement évidé dans le bras de crémaillère
(13).
15. Dispositif d'enroulement selon l'une quelconque des revendications précédentes, dans
lequel l'arbre de ressort (53) est excentriquement agencé par rapport à l'axe de rotation
(L3) du tambour (5).
16. Dispositif d'enroulement selon l'une quelconque des revendications précédentes, dans
lequel le moyen de ressort (41) comprend au moins un ressort hélicoïdal (41) et dans
lequel l'arbre de ressort (53) est excentriquement agencé par rapport au ressort hélicoïdal
(41).