US 3611245 A
Description (OCR text may contain errors)
United States Patent [1 1 3,61 1,245
 Inventor George 0. Puerner  R f n e Cited fin s UNITED STATES PATENTS [211 P 4 2,654,641 10 1953 Veatch 338/197 x  F1led Feb. 16, 1970 2,781,436 2/1957 Barden 338/134 X  Patented 2 B74 254 2 1959 1) '1 338 31  Assign akManorystcmdnm ary 5 X 3,386,068 5/1968 F1ll1ette 338/128 Indianapolis, Ind.
Primary lz'xaminerLewis H. Myers Axxixlanl Examiner-Gerald P. Tolin l l CONTROL UNIT WITH IMPACT CONTROL Allurnvyx-Richurd H. Childrcss, Robert F. Meyer, Henry W.
MOUNTING CUSHI Cummings and C. Carter Ells, Jr. 5 Claims, 2 Drawing Figs.
52 u.s.c1 339 154,
333/320 ABSTRACT: A control unit having two variable resistors con-  lnt.Cl H0lc9/02 nccted in tandem wi h ne each connected to concentric  Field of Search 338/98, Shafts utilizes an mpact cushioning means to absorb shock [28, 134, I97, 315, 320 loads imposed on the central shaft.
PATENTEU C 5 I INVENTOR ATTORNEY FIG 2 GEORGE o. PUERNER KKK CONTROL UNIT WITH IMPACT CONTROL MOUNTING CUSHION This invention relates to a novel control unit. More particularly, it relates to a control unit which utilizes two variable resistors mounted in tandem and an impact cushioning means therefor.
There are many instances in the appliance industry wherein variable resistance control units are used to perform independent functions with the units being independently operable off individual shafts. For example, in car radios two variable resistance units may be used to independently control the volume and the tone of the radio. In such applications, the two variable resistors usually operate off of independently operable shafts with a common axis. A common axis arrangement in such applications usually comprises a centrally disposed shaft and a sleeve concentric with and surrounding the central shaft to form the second shaft.
Further in such arrangements, the variable resistance units are usually held in tandem relationship with one being connected to the other in order to form a solid, compact unit. Also the centrally disposed shaft should, of necessity for ease of operation, extend beyond the concentric shaft. In such arrangements, it has been found that considerable damage occurs when the centrally located shaft is accidentally struck. More specifically, prior to the present invention, the central control units did not provide for means for cushioning such accidental blows such that the impact is transferred to the resistor unit connected to the concentric shaft.
The present invention is concerned with a control means wherein there are two variable resistors and has as one of its objects the provision of such a control unit wherein the variable resistors are independently operable off of shafts having a common axis.
Another object of the invention is to provide such a control unit wherein a central shaft is disposed in a concentric sleeve acting as the second shaft.
A further object of the invention is to provide such a control unit wherein cushion means are provided to cushion impact blows delivered in the unit.
Still a further object of the invention is to provide a control means including two variable resistors, one carried on a central shaft, the other carried on a concentric shaft, the two resistors being connected together with means coupling the resistor responsive to the concentric shaft to a mounting means so as to provide a cushion for impact blows.
These and other objects of the invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a cross section of the control means of the present invention;
FIG. 2 is a view similar to HO. 1 showing another mode of operation of the control means.
Generally speaking, the objects of the invention are accomplished by providing in combination a pair of variable resistor units substantially aligned and connected to each other, and a mounting means carrying the variable resistor units, concentric drive shaft means one each coupled to each of the variable resistor units, and impact cushioning means coupling one of said resistor units to the mounting means.
Referring now to the drawings, a control means includes first and second variable resistor means 12 and 14 which are mounted on or carried by a suitable mounting means 15. Mounting means 16 could include, for example, a panel or dashboard of an automobile. Each of the resistor units include a cup-shaped housing 18 and 18', terminal boards 20 and 20', the terminal boards including resistance paths 22 and 22', contact brushes 24 and 24', and rotor drive means 26 and 26' to rotatably drive the contact brushes.
The control means 10 also includes a shaft means 28 which includes a centrally disposed shaft 28' and a concentric sleeve 28" acting as the second shaft. As shown, rotor drive means 26 is coupled to an responsive to central shaft 28' while rotor drive means 26' is coupled to and responsive to concentric shaft 28". Knobs 30 and 32 are coupled to shaft 28' and 28" respectively in order to easily manually rotate the separate shafts. Thus there is provided two shafts having a common axis through which the resistor units 12 and 14 may be independently operable. C-ring l7 locates and prevents excessive axial movement of resistor unit 12 when central shaft 28' is axially displaced and thereby acts as a stop means.
The cup-shaped housing 18 of the variable resistor means 12 is closed by cover means 34. Cup-shaped housing 18' of variable resistor means 14 is suitable connected to cover means 34 through suitable means such as rivets (not shown). Cup-shaped member 18' is closed through cover means 36 which according to the invention includes cushion means 38 such as a thin spring washer to absorb impact loads. The spring washer is coupled to a collar 40, the collar in turn being coupled to the mounting means 16 through suitable means such as a nut 42.
When knob 30 is accidentally struck by a blow in the direction of the arrow shown in FIG. 2, shaft 28' is forced against the base of cup-shaped member 18 through bearing surface 44. Further axial movement of central shaft 28' is prevented by C-ring 17 which acts as a stop means and abuts against the base of cup-shaped member 18', the impact load then being transferred through resistor unit 14 to mounting means 16. Prior to the present invention, when this occurred, resistor unit 14 was pennanently deformed. In the present invention, cushion means 38 is deflected (FlG. 2) to absorb the impact, the cushion means then being returned to its original position.
Thus there is described a control unit wherein there are at least two variable resistor units carried by separate concentric shaft means, with means to cushion impact loads.
What is claimed is:
1. A control means comprising:
a. first and second variable resistor units connected to each other in tandem,
b. first drive shaft means coupled to said first variable resistor unit,
c. second drive shaft means concentric with said first shaft means coupled to the other of said second variable resistor units,
d. collar means surrounding said second drive shaft means and coupled to mounting means,
e. impact cushioning means coupled to said second variable resistor unit, and
f. stop means carried by said first drive shaft means engaging said second variable resistor unit upon axial displacement of said first drive shaft means.
2. The combination according to claim 1 wherein said impact cushioning means includes a spring means.
3. The combination according to claim 2 wherein said spring means includes a thin spring washer.
4. A control means according to claim I wherein said stop means includes a C-ring fixed to said first drive shaft means.
5. A control means comprising:
a. a first cup-shaped housing carried by a first drive shaft,
and a cover closing same,
b. a terminal board disposed in said housing, said terminal board including resistance paths,
c. a rotor means disposed within said housing and responsive to said shaft, said rotor carrying contact brushes engaging said resistance paths,
d. a second cup-shaped housing carried by a second drive shaft that is concentric with said first drive shaft, said cupshaped housing connected to said cover of said first named housing,
e. a terminal board disposed in said second named housing, said terminal board including resistance paths, a rotor means disposed in said housing and responsive to said second drive shaft, said rotor carrying contact brushes engaging said resistance paths,
f. cover means closing said second named housing including impact cushion means,
h stop means carried by said first drive shaft engaging said second cup-shaped housing upon axial displacement of said first drive shaft.