Rotary shafts – gudgeons – housings – and flexible couplings for ro – Overload release coupling – Torque transmitted via frictional engagement of planar...
Reexamination Certificate
1993-12-17
2001-02-20
Walsh, Donald P. (Department: 3653)
Rotary shafts, gudgeons, housings, and flexible couplings for ro
Overload release coupling
Torque transmitted via frictional engagement of planar...
C464S046000
Reexamination Certificate
active
06190258
ABSTRACT:
TECHNICAL FIELD
The invention herein resides in the art of power transmission devices and, more particularly, to torque limiters. More specifically, the invention presents a multiple disc torque limiting clutch.
BACKGROUND ART
The use of torque limiting clutches between input power sources and output mechanisms is well known. Typically, a torque limiting clutch has a characteristic breakaway torque allowing slippage between input and output shafts or mechanisms when the torque on the shafts exceeds the characteristic breakaway torque of the clutch.
The prior art, while being generally effective in performing the requisite torque limiting functions, has demonstrated shortcomings in a number of areas. Particularly, increased ease of assembly and disassembly of such clutches is of continual concern. Additionally, the adaptability of one output shaft to any of plural clutches, as well as the adaptability of a single clutch to any of plural output shafts is most desirable.
Further, while the use of Belleville springs in torque limiting clutches has previously been known, it has not been known to employ a Belleville spring in conjunction with spring cup assemblies to achieve a torque limiting clutch having high breakaway torque characteristics, which characteristics may be grossly attained by implementation of the Belleville spring, and finely set by implementation of the spring cup assemblies.
Additionally, previously known torque limiting clutches have not been given to ease of separation of an output shaft and hub from the remainder of the clutch assembly and which particularly allow for such separable feature to accommodate a shrink fit or other interference fit between the output hub and the output shaft. Specifically, heat shrink fitting has typically been avoided in the prior art because the interconnection between the output hub and output shaft has generally been undertaken at a point when the torque limiting clutch assembly has been complete. At that point in time, heating of the output hub will likely cause damage to the friction elements, springs, and bearings of the clutch, an undesirable result.
DISCLOSURE OF INVENTION
In light of the foregoing, it is first aspect of the invention to provide a multiple disc torque limiting clutch which is characterized by ease of assembly and disassembly.
Another aspect of the invention is the provision of a multiple disc torque limiting clutch in which a single clutch may be adapted for implementation with any of numerous output shafts and hubs and, similarly, an output shaft and hub may be employed with any of numerous clutches.
Another aspect of the invention is the provision of a multiple disc torque limiting clutch which employs the combination of a Belleville spring and spring cup assemblies to establish the characteristic breakaway torque.
Another aspect of the invention is the provision of a multiple disc torque limiting clutch which allows for ease of separability of the output hub from the torque limiting clutch.
Yet an additional aspect of the invention is the provision of a multiple disc torque limiting clutch which allows for ease of heat shrink fitting or interference fitting of the output hub onto the output shaft.
Still a further aspect of the invention is the provision of a multiple disc torque limiting clutch which is reliable and durable in operation, compact in size, and economic to produce employing state of the art techniques and apparatus.
The foregoing and other aspects of the invention which will become apparent as the detailed description proceeds are achieved by a torque limiting clutch, comprising: first and second end plates maintained in fixed spaced apart relationship to each other; friction discs interleaved with separator discs between said first and second end plates; a pressure plate interposed between said first end plate and said interleaved friction discs and separator discs; spring means interposed between said first end plate and said pressure plate for urging said pressure plate toward said second end plate and urging said friction discs and separator discs into frictional contacting engagement with each other; an output shaft; and an output hub received upon said output shaft, said friction discs being splined to said output hub, said output hub and output shaft being separable from said friction discs as a unit.
Other aspects of the invention which will become apparent herein are attained by a torque limiting clutch assembly, comprising: first and second fixedly interconnected end plates; interleaved friction discs and separator discs maintained between said first and second end plates; a pressure plate interposed between said first end plate and said interleaved friction discs and separator discs; spring means engaging said pressure plate and urging said friction discs and separator discs into frictional engagement; said first and second end plates, friction discs, separator discs, pressure plate and spring means comprising a first unit; an output hub received upon an output shaft and comprising a second unit; and wherein said second unit is selectively engageable and disengageable with said first unit.
REFERENCES:
patent: 2618136 (1952-11-01), Wellauer
patent: 2655015 (1953-10-01), Linder
patent: 2702619 (1955-02-01), Andershock
patent: 3277671 (1966-10-01), Winstone et al.
patent: 3372561 (1968-03-01), Howard et al.
patent: 4440035 (1984-04-01), Foulk
patent: 4445876 (1984-05-01), Entrup
patent: 4661083 (1987-04-01), Heidenreich et al.
patent: 5002517 (1991-03-01), Heidenreich et al.
patent: 5119995 (1992-06-01), Kohler et al.
patent: 5129497 (1992-07-01), Kelley
patent: 5295909 (1994-03-01), Heidenreich
patent: 1 747 750 (1992-07-01), None
patent: 0 012 966 (1990-11-01), None
Heidenreich David C.
Nichols Keith A.
Power Transmission Technology, Inc.
Renner Kenner Greive Bobak Taylor & Weber
Rivera William A.
Walsh Donald P.
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