The present invention relates to a hoist arrangement coπprising a rotatably mounted w__n__ing axle and a flexible hoist element, such as a belt, intended to be wound onto and unwound from the winding axle and to exert a pulling force on a ovably mounted operating arm for controlled movement of said arm as the length of the hoist element between said axle and said operating arm is extended or shortened, wherein movement of the qperating arm is corresponded by a hoist movement.

Arrangements of this kind are known to the art. For instance it is known from sunbeds equipped with an electrically raisable and lσwer- able upper part to connect the upper part of the sunbed to a pivot .shaft which extends in the longitudinal direction of the bed. The .shaft is rotated try means of an electric motor, through the inter¬ mediary of a winding axle capable of being rotated by the motor, and a hoist element which is disposed between the axle and an operating arm that projects outwardly transversely to the axle and which is intended to be wound on and unwound from said winding axle in order to shorten or lengthen respectively the free length of the hoist element between the axle and an outer part, such as an end part of the operating arm, so as to rotate the rotational axle. The hoist arrange- ment is cxDnstructed so that when the motor winds the hoist element onto the winding axle, in response to a hoisting impulse given by a control device, whereby the operating arm is pivoted, the pivot shaft is rotated and the upper part of the sunbed is raised, i.e. swung upwards, and so that when the motor receives a lowering impulse from a control device, the hoist element is unwound from the winding axle and said upper part is lowered under the action of its own weight. Limit switches are provided to determine a highest and a lowest level of the upper part.

Particularly with arrangements which can be raised and lowered manuall in addition to electrically, it is possible to lose control over the hoist element and therewith lose the function of the arrangement. In the case of some arrangements, lowering of the upper part electri-

cally followed by an additional lowering impulse can cause the hoist element to change its winding direction on the winding axle subsequent to having first passed a neutral position, wherewith continued rotation of the pivot shaft or rotational shaft in the "lowering direction" causes the upper part to be raised instead.

The present invention provides a hoist arrangement which affords a .solution to the problems associated with known techniques.

Accordingly, the invention relates to a hoist arrangement which comprises a rotatably mounted winding axle and a flexible hoist element, such as a belt, which is intended to be wound onto and unwound from said w__nding axle and which exerts a pulling or tension force on a mσvably mounted operating arm for controlled movement of said arm during extension or shortening of the section of the hoist element located between the winding axle and the operating arm, wherein irovement of the operating arm is corresponded by hoist movement.

The inventive hoist arrangement is especially characterized by a spring-loaded stret_hing or tensioning device which functions to hold the hoist element stretched; and try a spring-loaded contact breaker arm which is intended to take a contact breaking position ∞__responding to a limit position of the hoist arrangement, wherein movement of the contact breaker arm is dependent on movement of the hoist-element st_retehir_g device, such that movement of a given kind to a contact breaking position of the st_ret____hing device is required in order for the contact breaking arm to adopt said contact breaking position.

The present invention will now be described in more detail with reference to an exemplifying embodiment thereof illustrated in the accompanying drawings, in which

- Figure 1 illustrates schematically an embodiment of a sun bed, seen transversely to its longitudinal direction, having an upper part which can be raised and lowered by means of the inventive hoist arrangement;

- Figure 2 illustrates the arrangement of Figure 1 from the right of said Figure;

- Figure 3 illustrates schematically an embodiment of the inventive

arrangement mounted on a panel included in apparatus according to Figures 1 and 2, as seen in section on the line A-A in Figure 5; - Figure 4 is a sectional view taken on the line B-B in Figure 5 and illustrates schematically the arrangement shown in Figures 1 and 2; an - Figure 5 illustrates schematically part of a panel on which there is mounted an arrangement acxxsrding to Figures 3 and 4, as seen from the right in Figures 3 and 4, with its rear piece removed.

In the illustrated embodiment, the hoist arrangement is intended for raising and lowering an upper part 1 of a sunbed, this upper part being pivotally connected or hinged to a co__respond__ng lower part 2 through the .Intermediary of a panel 3 and is rotatable y means of a rotational or pivotal shaft 4, Figures 2-5, essentially in connection with one long side 5 of the upper part 1.

As will be seen from Figures 3-5, the hoist arrangement is mounted on the panel 3 and includes a winding axle 7, a motor 6 which rotates the axle 7, and a flexible hoist element 8, a belt 8, which is intende to be wound onto and unwound from the winding axle 7 and to exert a pulling or tension force on a pivotally mounted operating arm 9, for controlled pivotal movement of the operating arm while extending or .shortening that section of the hoist element located between the operating arm and the winding axle. Pivotal movement of the opera¬ ting arm 9 is intended to be corresponded try a hoist movement. In the case of the illustrated arrangement, the operating arm is mounted on the pivot shaft 4 essentially transversely thereto and is arranged to rotate the pivot shaft 4 so as to pivot the upper part 1, such as either to raise or to lower the same. In the illustrated embod_-_rent, each end 10 of the pivot .shaft carries an attachment arm 11, both attachment arms being intended for pivotal movement of the upper part of the sunbed.

In the embodiment of the hoist arrangement illustrated in Figures 3- 5, the hoist element 8 extends from the winding axle 7 over a first guide means 12, such as a guide wheel 12, mounted on an outer part 13 of the operating arm 9, and passes from the operating arm to an anchorage means 14, via a further guide means 15 mounted adjacent the winding axle, wherein two sections or runs 8', 8" of the hoist element

extend substantially adjacent one another at the first guide means 12 and are located substantially between the operating arm and the winding axle, with the respective axes of the winding axle 7, the pivot shaft 4 and the guide means 12, 15 being essentially parallel with one another.

The reference 16 identifies a spring-loaded tensioning or st_retc_hing device which functions to hold the hoist element 8 stretched. In the case of the illustrated erifoodiment, the stretching device includes a tensioning arm 17 which is pivotally mounted on the winding axle and which is intended to be spring-biased into abutment with the hoist element 8 by means of a substantially axially extending contact part 18. In the illustrated case, abutment is effected against the section 8" of the hoist element 8 extending between the anchorage means 14 and the operating arm.

The reference numeral 19 identifies a spring-loaded electrical contact breaking arm, the movement of which is coupled to the movement of the stretching or tensioning device, such that movement of the contact breeaking arm is contingent on novement of the st_retehing device. In this eiijbodiment, the contact breaking arm is pivotally mounted on the winding axle and is .spring-biased into abutment with the st_retohing device, as illustrated schematically in Figure 4. The contact breaking arm is intended to pivot to a contact breaking position corresponding to a first limit position of the hoist arrangement. The reference numeral 20 identifies a first switch arranged in the pivoting directio of the contact breaking arm 19 and which breaks the supply of current to the motor when activated by said arm. In order for the contact breaking arm to pivot to its contact breaking position, it is necessar for the st_retehing or tensioning device to adopt a contact breaking position. The hoist arrangement has a second limit position, which is obtained with the aid of a second switch 21 which is activated t_hrough the operating arm, for instance by means of a resilient contact arm 22 mounted on the operating arm and intended to activate the second switch 21, so as to interrupt the supply of current to the motor when the operating arm pivots to a predete ined extent.

In the case of the illustrated embod-Lment, said limit positions

correspond to the movement limit positions of said upper part, more specifically an upper and a lower limit position. Breaking of the current supply when lowering the upper part 1 of the sunbed, cor- re-sponding to pivotal movement of the operating arm clockwise in Figures 3 and 4 and a bottom limit position, is effected try lowering the upper part against a stop means, such as against the lower part 2 of the sunbed wherein the hoist element is lengthened during s_Lmul- taneσus movement of the stoetohing device 16 and the contact breaking arm 19 as a result of continued rotation of the winding axle 7, and wherein, subsequent to the hoist element having been lengthened to a predetermined extent, the stretching device is intended to take a contact breaking position subsequent to having executed said predeter¬ mined movement, such that the contact breaking arm will break or interrupt the supply of current to the motor.

When the upper part is raised mechanically, i.e. by means of the motor and not manually, current supply to the motor is interrupted at an upper limit position, corre_=ponding to pivotal movement of the operating arm in an anticlockwise direction in Figures 3 and 4, this interruption of current supply being effected in the aforedescribed manner by means of said second breaking means.

There is illustrated a sunbed construction, including an upper part and a lower part, substantially in accordance with Swedish Patent No. (Patent Application 8804492-0) , where a gas spring device

23, Figures 1 and 2, acts between the upper part and, e.g., the lower part, this gas-spring device being provided with friction means for braking or retarding the mutual displacement of the housing part and axle part of said arrangement and functioning to fixate the housing part and the axle part in relation to one another in selected posi¬ tions.

The manner in which the inventive arrangement operates will be under¬ stood essentially from the aforegoing. Movements carried out by the hoist element are held under control by means of the hoist-element tensioning or steetiiing device, while the hoist element assists in regulating movement of the stretohing device and therewith movement of the contact breaking arm. Because pivotal movement of the operating

arm is hindered by some form of stop means, which specifies a bottom limit position, while the winding axle continues to rotate until current supply is .Interrupted by means of the electric contact breaking arm, this bottom limit position will always be taken in a positive and definite fashion.

As will be understood from the aforegoing, the invention affords several important advantages. For instance, the hoist element is constantly under full control, even when the upper part of the .sunbed is lifted manually, so as to slacken the tensioning or stret___hing device. Furthermore, the upper part of the sunbed will always move to the full extent of its lower and upper limit positions. Subsequent to a limit position having been reached, it is iπpossible, by restarting the motor, to rotate the winding axle in the same direction of axle rotation as that prior to reaching a respective limit position, and the axle can therewith only be rotated in an opposite direction. This prevents the axle from being rotated beyond the limit position in which the hoist element is fully unwound and herewith that the limit position is passed and the hoist element is wound-up in a new winding direction.

Although the invention has been described in the aforegoing with reference to an exenplifying eπd_odiment thereof, it will be understood that other embodiments and minor modifications are conceivable within the scope of the inventive concept.

It will also be understood that the inventive hoist arrangement can be applied in contexts other than sunbeds.

The operating arm, the tensioning or stretching device, the contact breaking arm, the switches etc. can also have configurations different to those illustrated. For instance, the stretching device and the contact breaking arm need not be mounted on the winding axle and the contact breaking arm need not act directly on the contact part 18 of the tensioning arm 17, etc.

It will also be understood that primarily the operating arm, the stretehing device and the contact breaking arm need not necessarily

execute a pivotal movement, but may be arranged to perform other types of movement, such as rectilinear movement, for instance.

The invention is therefore not restricted to the aforedescribed and illustrated exenplifying embodiments thereof, since modifications can be made within the scope of the following claims.