Patent Publication Number: US-4224960-A

Title: Wind-up device for flexible conduits, such as hydraulic hoses

Description:
The present invention relates to a device for winding up flexible conduits, such as hydraulic hoses, said device comprising at least one wind-up drum having a hub which is rotatably mounted on a shaft, at least one flexible conduit adpated to be wound up on said wind-up drum being connected to at least one connector extending through said hub and shaft and opening into a fixation-end portion of said shaft, and at least one coil-spring means is so connected with the shaft and with the wind-up drum as to cause at least one coil-spring forming part of said coil-spring means to become tensioned when, upon unwinding the conduit from the wind-up drum, the wind-up drum is rotated relative to the shaft. 
     In wind-up devices of the above-stated type, the coil-spring means should be capable of rapid replacement without releasing portions of the system, for instance so that a vacuum pressure therein will be disturbed or so that any liquid contained therein will be spilled out. However, in previosly known constructions it is impossible to carry out a rapid replacement of the coil-spring means because such a replacement involves extensive labour, for instance disassembly of the wind-up drum from its shaft, releasing sealing elements and components forming part of the system, accompanied by the risk, on one hand of damage to the sealing elements and, on the other hand, of disturbing any vacuum pressure, and further of spillage of, for instance, oil contained in the system. 
     The object of the present invention is to eliminat these drawbacks and, in the arrangement stated in the opening paragraph, to make provisions for enabling, with simple means, a rapid replacement of the coil-spring means without any need of releasing internal parts of the construction. This, according to the invention, is enabled substantially by the fact that the coil-spring means is detachably mounted on an outer end-portion of the shaft opposite to its fixation-end portion and at the end of the wind-up drum remote from the fixation-end portion of the shaft. 
    
    
     The invention will be described more in detail hereinafter with reference to the accompanying drawings, in which: 
     FIG. 1 is a cross-section view illustrating a wind-up device according to the invention; 
     FIG. 2 is a cross-section view of the wind-up device and taken along lines II--II in FIG. 1; 
     FIG. 3 is a cross-section view illustrating an alternative embodiment of the inventive wind-up device. 
    
    
     The wind-up devices illustrated in the drawings by way of example only are intended for winding up flexible liquid conduits, or hoses, 1. The wind-up devices comprise a shaft 2, one end of which constitutes a fixation-end portion 2a which is adapted to be secured to a fixed carrier member or the like (not shown). The fixation parts forming part of the fixation-end portion 2a are previously known, per se, and thence, need neither be shown, nor described more closely. 
     Rotatably mounted on shaft 2 is a wind-up drum 3 commprising an outer portion 3a consisting of three wall elements 3b, 3c and 3d defining together two circular spaces 3e, 3f for accommodating the flexible hydraulic conduit, or hose, 1. The outer portion 3a is attached to a housing which is rotatably mounted on the shaft 2. The hydraulic conduit or hose 1 passes to the hub 2 through openings 3k in the outer portion and is connected to connectors so as to communicate with flow connections in the form of passageways 3p, 3r in the hub and 2b, 2c in the shaft 2. The passageways 2b, 2c extend through shaft 2 towards the fixation-end portion 2a, where they are terminated in such a way as to be able to communicate with flexible conduits or hoses (not shown) connected to the shaft 2. 
     The wind-up devices illustrated further comprise a coil-spring assembly 4 including a coil-spring 4a (or two coil-springs, as shown in FIG. 3) which has its inner end connected to the stationary shaft 2 and its outer end to the wind-up drum 3, whereby it will be tensioned when the wind-up drum 3 is rotated by the unwinding motion of the hydraulic conduit 1, thereby tending to pull back the unwinded portion of the hydraulic flexible conduit. 
     To enable the coil-spring assembly 4 to be replaced rapidly and without any need of uncovering or exposing the passageways 3p, 3r and 2b, 2c, this spring assembly is detachably mounted on an outer end portion 2d of the shaft 2 opposite to its fixation-end portion 2a and at the end 3b of the wind-up drum 3 remote from the fixation-end portion 2a. 
     The coil-spring assembly 4 preferably comprises a spring hub 4b detachably mounted on the outer end portion 2d of the shaft, this hub serving, on one hand, as an anchorage element for one or more of the springs 4a of the coil-spring assembly 4, and, on the other hand, as an axial pressure bearing holding the hub 3g of the wind-up drum 3 in place on the shaft 2. 
     The spring hub 4b is suitably secured to the shaft 2 by a center-screw 4c and at least one fixation element 4d (such as a set screw, for example) which is located in an eccentric position and adapted normally to prevent any rotation of the spring hub 4b relative to the shaft 2. By removing the fixation element 4d and releasing the center screw 4c, the spring hub 4b can be rotated relative to the shaft 2, thereby tensioning or releasing the coil-spring 4. 
     To obviate the need of providing different springs for enabling winding-up in either sense, the coil-spring 4 is provided with dual brackets 4e which enables the same to be connected to the wind-up drum 3 with either end, 4f or 4g disposed next to the wind-up drum. Each bracket 4e suitably comprises, on one hand, apertures 4h, 4k made in a symmetrically projecting portion 41 of a casing 4m forming part of the coil-spring assembly 4, and, on the other hand, through-bolts 4n passing throug said projecting portion 41 and the apertures 4h, 4k. 
     Since, when the coil-spring assembly 4 is to be replaced, dissassembly of the wind-up drum 3 from the shaft 2 need not be undertaken, the sealing arrangement for sealing the passageways 2b, 3p and 2c, 3r may comprise sealing rings 5, 6, 7 and 8 disposed in annular grooves 3s, 3t formed in the hub 3g. 
     Details less essential for the invention and previously known have been omitted from description. It may be mentioned, however, that the enclosure of the coil-spring assembly 4 is suitably perfectly symmetrical, and that the extreme end of the coil spring is connected to said enclosure in a manner known per se. The end portion 3a of the wind-up device 3 may be detachably secured to the hub 3g, such as by screws 3v. The wind-up device, of course, is applicable for use with other types of flexible conduits than hydraulic hoses, such as for flexible conduits for other liquids or for gases or for electric cables etc. In other words, the embodiment here described is merely illustrative of the invention without limitation otherwise than as defined by the features disclosed in the appended claims.