US 3065925 A
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Description (OCR text may contain errors)
Nov. 27, 1962 N. A. APPLETON TAKE-UP REEL Filed Feb. 4, 1960 I a e 3 :Il' match, (R
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United States Patent O 3,065,925 TAKE-UP REEL Norton A. Appleton, Northfield, Ill., assignor to Appleton Electric Company, Chicago, Ill., a corporation of Illinois Filed Feb. 4, 1960, Ser. No. 6,685 3 Claims. (Cl. 242-1075) The present invention relates to improvements in takeup reels of the type comprising a drum carrying a cord or cable journaled on a shaft which is mounted in a frame or housing with a main drive spring fixed between the drum and the shaft for rewinding cord which has been pulled out from the drum.
More specifically, the present invention relates to a takeup reel assembly of the foregoing type having as an improvement a novel tension adjustment and overrun clutch mechanism.
In the running out of cord from take-up reels it is oftentimes desirable to be able to adjust the tension applied by the main rewind spring on the cord, either to increase the winding tension or decrease it. Take-up reels of the character embodying the present invention generally include a locking device for the purpose of effecting automatic locking of the drum against rotation when a length of cord or cable has been run out and the main drive spring wound. Most such locking devices, when released, require a slight delay in drum rotation, rotation below a certain minimum speed or a reverse rotation, before they engage and hold the drum against rotation. Such locking devices are shown in US. Patent No. 2,745,912 to Meyer and in my copending application Serial No. 742,286, filed June 16, 1958, for Take-Up Reel. In the event a cord which has been pulled out from the drum should break before the releasable locking device is engaged, the rewind motor will turn the reel to wind up the cord. The reel and cord having some weight, the reel will gain an inertia as it is rotated by the spring. Because there is no tension on the broken cord tending to slow the rotation of the reel, the reel will continue to rotate after the spring is completely unwound and thereby effect a reverse winding of the spring, often causing the spring to break or become damaged.
It is accordingly the primary aim of the invention to provide an improved take-up reel mechanism for preventing reverse winding of the main spring and at the same time provide means for adjusting the tension applied to the spring. More specifically, it is the object of this invention to provide, in a reel of the foregoing character an improved combination tension adjustment and overrun clutch mechanism in which the clutch can be released, and the tension adjusted independently thereof.
One object of the present invention is to provide a takeup reel assembly of the foregoing character which includes a tension adjustment and overrun clutch arrangement in a novel correlation so that should the reel rotate past the unwound position of the spring, the main drive spring will not be damaged.
It is a further object of the present invention to provide an overrun clutch and tension adjustment of the foregoing character in which the susceptibility to wear of the clutch during adjustment of the reel spring tension is avoided. A more detailed object is to provide a tension adjustment mechanism which includes a knob releasably engageable with the clutch mechanism so that the clutch will not be damaged during tension adjustment.
Still a further object of the invention is to provide a clutch of the above character in which the force tending to hold the clutch engaged can be readily varied.
Other objects and advantages will become apparent as the following description proceeds taken in connection with the accompanying drawings wherein:
3,065,925 Patented Nov. 27, 1962 FIGURE 1 is a vertical elevation view of a take-up reel embodying the present invention with a portion of the housing cut away.
FIGURE 2 is an enlarged perspective view, with parts broken away of a take-up reel embodying a tension adjustment and overrunning clutch mechanism illustrative of the present invention. 7
FIG. 3 is an enlarged, fragmentary section View illustrating in further detail the overrun clutch arrangement.
FIG. 4 is a view similar to that of FIG. 3 but showing the clutch in a position wherein the reel and shaft rotate relative to the housing.
FIG. 5 is a perspective view of clutch plates employed in the clutch mechanism of FIG. 3.
FIG. 6 is an elevation view of a clutch plate shown in FIG. 5.
While a certain illustrative embodiment has been shown in the drawing and will be described below in considerable detail, it should be understood that there is no intention to limit the invention to the specific form disclosed. On the contrary, the intention is to cover all modifications, alternative constructions, equivalents, and uses falling within the spirit and scope of the invention as expressed in the appended claims.
Referring more specifically to the drawing, the invention is there shown embodied in an illustrative take-up assembly which in the present instance comprises a housing 11 attached to a supporting flange, swivel or the like 12. Preferably, the housing 11 is defined by a pair of opposed dished sheet metal shells 14, 15 having their contacting peripheral portions mechanically engaged in any suitable manner. One means for joining the two dished shells includes the use of an annular channel shaped member 16 having in-turned flanges which are mechanically engaged to the inside surface of the peripheral edges of the housing shells as by spot welding.
Iournaled in a socket 18 mounted centrally on the inner surface of one of said dished walls 15 and extending through a central aperture through the opposite dished wall 14, is a drum supporting shaft 19. In the present device, the extremity of the shaft extending through the housing wall 14 is provided with an annular collar 20 which abuts the inner surface of the housing wall 14 and thereby prevents the shaft from sliding longitudinally with respect to the housing.
A reel or drum 21 is journaled for rotation on the shaft 19 and is restrained against axial movement therealong. The drum 21 is adapted to receive a length of hose or cord 22 and to store the same in convolutions thereon. In the present instance the drum is provided with a length of electrical grounding cord 22 having a free end which extends tangentially from the drum, passing out of the housing via an enlarged circumferential aperture (not shown). The drum 21 is biased toward thewound position by means of a spring such as a relatively heavy spirally-wound clock spring 28 fixed to the drum at one end and having its other end connected to the shaft 19, as shown in FIG. 2.
In accordance with the present invention, provision is made for preventing the drum from running wild and causing a reverse winding of the main drive spring, and at the same time for changing the tension on the spring. To this end there is provided a novel tension adjustment means and an interrelated overrun clutch means acting between the shaft 19 and the adjacent housing wall 14, for
the purpose of releasahly connecting the shaft to the housis fixed against rotation thereon. For engaging the knob the reel wall =14 is provided with an annular clutch 30 fixed on its outer surface in surrounding relation with the shaft and provided with a plurality of outwardly directed projections 31, three for example as shown in the drawing, releasably engageable with a corresponding plurality of slots 32 in the hand knob 29. The clutch disc 30 is fixed to the housing wall 14 by any suitable means such as welding and preferably is provided with a plurality of small spaced apertures 34 which receive corresponding locating pins 35 projecting from the housing wall.
The knob 29 is preferably cup-shaped in configuration and is formed with a fiat face 36 in which the slots 32 are cut and which is directed generally towards the clutch disc 30. The end 38 of the shaft 19 receiving the knob is preferably squared and extends through a correspondingly squared hole 39 in the knob so that the knob can move axially but is restrained against rotation. To facilitate gripping, the knob may be knurled on its outer peripheral surface.
For biasing the knob face 36 against the clutch disc 30, a spring 40 is positioned within the cup-shaped knob and acts between the inner surface of the knob and a plate 41 secured to the end of the shaft by a suitable screw 42. The plate 41 is preferably dished inwardly to provide an inner shoulder 44 against which the spring seats so that it is centered within the knob.
In order to prevent rotation of the shaft and knob in one direction only, the projections 31 on the clutch disc are each formed with a circumferentially directed abrupt shoulder 45 opposite a smoothly inclined cam-like surface 45. All of the shoulders 45 face one circumferential direction which is the same as the direction of rotation of the drum 21 as the cord 22 is withdrawn, and, accordingly, all of the cam surfaces 46 are directed in the opposite or rewind direction of drum rotation. The cam surfaces 46 must be of a sufficient slope to provide a driving connection between the housing and the shaft in order to rewind the drum and yet inclined enough so that a reverse winding of the spring is prevented should the drum rotate freely, by inertia-drive as would occur in the case of a broken cord or cable. Slippage between shaft and housing in one direction is necessary in order to prevent reverse winding of the main spring should the drum be driven in such direction as to effect reverse winding. The spring 40 urges the knob against the clutch disc 30 and, by selecting the desired spring force, the force required to cause the clutch to become disengaged so that the projections 31 slip out of the slots 32 can be determined. Thus, the sloping surfaces 46, apertures 32, and spring 40 are designed to act as an adjustable click-brake so as to slow the rotation of shaft 19 and drum 21 but not to positively prevent rotation of the shaft 19 should the cord break and the drum 21 rotate in a reverse direction tending to reverse-wind spring 28. Accordingly, reverse winding of the main spring 28 is prevented.
Adjustment of the main spring tension independently of the clutch can be readily accomplished with the foregoing structure by simply pulling the knob 29 axially outwardly against the force of the spring 40 thereby releasing the projections 31 from engaging within the slots 32 and then rotating the knob 29 in the direction desired such as in the direction for winding the spring. When the drum is held stationary, rotation of the knob turns the shaft and in turn. adjusts the tension on the main spring 28. When the desired spring tension has been obtained and the knob 29 is released so that the clutch disc 30 is engaged by the engagement of the projections 31 with the slots 32, as shown in FIG. 3, the shaft will be prevented from rotating relative to the housing by the aforesaid enga ement. As the shoulder 45 on the disc 30 will abutthe adjacent edge of the slot 32, the spring 28 will react against the shaft and thereby rotating the reel drum in a direction tending to wind the cord thereon.
Should the cord break when it is withdrawn and the drum is undertension, unless theautomatic latch engages,
the drum will rotate rapidly and uncontrollably. After the spring is completely unwoundyfurther rotation of the drum in the same direction will not damage the spring by reverse winding it but will cause the cam surfaces 46 to ride up onto the face 36 of the knob 29 as shown in FIG. 4, and the shaft will rotate along with the drum. With the foregoing construction, it will be observed that many advantages are obtained among which are the reduced likelihood that the clutch disc will be damaged or worn during tension adjustment and the relative ease of tension adjustment. If it is desired to change the clutch tension, it is a simple matter to replace the spring 40 with one capable of exerting a different force on the knob.
I claim as my invention:
1. An overrunning clutch and tension adjustment device for use with a take-up reel comprising a housing, a shaft mounted in said housing, a drum journaled on said shaft and carrying a cord, a main driving spring fixed between said drum and said shaft for driving said drum thereby rewinding cord withdrawn therefrom, said overrunning clutch and tension adjustment device comprising, in combination, first means mounted in axially sliding relation on the shaft for rotation therewith and including a plate member having a plurality of equally spaced apertures therein, second means fixed to said housing and having a plurality of spaced projections corresponding to said apertures, said projections including an abrupt shoulder facing in one circumferential direction and an opposed inclined cam surface facing in the opposite circumferential direction, a spring urging said first and second means together, said first means including an outwardly turned rim defining a knob for use in disengaging said apertures and projections and for rotating said plate member and said shaft to tension the main drive spring within the drum, and a plate fixed to the end of said shaft in spaced parallel relation with said plate member including said spring enclosed within said knob and acting between said plate and said plate member for urging the latter into clutch relationship with said second means.
2. An overrunning clutch and tension adjustment device for use with a take-up reel comprising a housing, a shaft mounted in said housing, a drum journaled on said shaft and carrying a cord, a main driving spring fixed between said drum and said shaft for driving said drum thereby rewinding cord withdrawn therefrom, said overrunning clutch and tension adjustment device comprising, in combination, a cup-like knob slidably mounted on the shaft and having a plate-like surface with a plurality of equally spaced apertures extending therein, a clutch disc fixed to said housing and having a plurality of outwardly directed spaced projections corresponding to the apertures in said knob, said projections including an abrupt shoulder facing circumferentially in the cord wind direction and an opposed inclined cam surface facing in the opposite direction, an inwardly dished plate fixed on the end of the shaft and extending within said cuplike knob, a spring enclosed within said knob and acting between said knob and said plate for urging said knob surface against said clutch disc, and an outer gripping surface on said knob for pulling the same axially away from the drum wall and for rotating the same to tension the main drive spring.
3. An overrunning clutch and tension adjustment device for use with a take-up reel comprising a housing, a shaft mounted in said housing, a drum journaled on said shaft and carrying a cord, a main driving spring fixed between said drum and said shaft for driving said drum thereby rewinding cord withdrawn therefrom, said overrunning clutch and tension adjustment device comprising, in combination, a cup-like knob slidably mounted on the shaft and having a plate-like surface, a clutch disc fixed to said housing, means interposed between said clutch disc and said knob surface including an abrupt shoulder received in an aperture, said abrupt shoulder facing in a directionto maintain said shaft substantially stationary against the urging of said main driving spring when said cord is unwound, an opposed inclined cam surface facing in the opposite direction to said abrupt shoulder, an inwardly dished plate fixed on the end of the shaft and extending within said cup-like knob, a spring 5 enclosed within said knob and acting between said knob and said plate for urging said knob surface against said clutch disc, and an outer gripping surface on said knob for pulling the same axially away from the drum wall and for rotating the same to tension the main drive spring. 10
References Cited in the file of this patent UNITED STATES PATENTS