US 2949043 A
Description (OCR text may contain errors)
Aug. 16, 1960 l.. J. FIGHTER ETAL LINK Filed Sept. 26, 1958 'Flc'.l
Y Y T 5. @H m M ml A :l lud A uw@ u Y Gl LEB F b n C xH/J 9 0 a m n li n\\\\\\\ l United. States Patent l ce 2,949,043 Patented Aug.. 16, 1960 LINK Ludwig J. Fichter, Chicago, and Edward J. Mastney, Hinsdale, lll.,lassignors to Oak Mfg. Co., a corporation of Illinois Filed Sept. 26, 1958, Ser. No. 763,591v 4 Claims. (Cl. 74-469) This invention relates to a link vand particularly to a link which may be easily disposed in position in various mechanisms. While the link forming the subject-matter of the present invention has general application, it may be used to great advantage in relatively light devices utilizing linkages as push butt-on operated mechanims for tuning communication equipment. As an example, a so-called treadle bar type of tuner has been widely used in automobile radios. This type of mechanism utilizes linkages which connect various parts.
The construction embodying the present invention is simple and may be positioned without the use of tools such as may be required for ilattening or spreading rivets or the like which are necessary in using conventional links.
In order that the invention may be understood, reference will now be made to the drawings Iwherein Figure 1 is a detail of a portion of a mechanism utilizing the new link.
Figure 2 is a section on line 2-2 of Figure 1.
Figure 3 is an enlarged detail on line 3--3.
Figure 4 is a view of a link embodying the present invention.
Figure 5 is an enlarged detail showing one end of the new link disposed in position on a pivot pin.
The mechanism with which the new link may be associated may have any -suitable construction and as illustrated here includes frame having end wall 11 and bottom wall 12. The two end walls, of lwhich 11 is one, may support pins 15 upon each of which rocking member 16 is supported. Rocking member 16 may be associated with suitable members to be operated such as, for example, the movable parts of the tuning system of a radio. For convenience only one part will be described, it being understood that such parts are generally duplicated.
As illustrated here, rocking member 16 has operating ann 17 having pivot 18 joined by link 19 to pivot 20. Pivot 20 is carried by movable member 22 which in this instance is adapted to move in a straight line. Member 22 is pnovided with tongues 23 and 24 which ride in slots 25 and 26 in each end wall. Excepting for the fact that link 19 is disposed between pivots 18 and 20 and constitutes the subject-matter of the present invention, the remaining mechanism is not important and may assume a wide variety of forms.
It is understood that the mechanism is similarly constructed at the two sides thereof and that link 19 and its pivot mounting will be duplicated at the two end walls. In apparatus of this general type, it is essential that no play at the linkage be permitted since the accuracy of the entire mechanism would be seriously impaired. It has hitherto been the practice to provide a simple link, instead of link 19, and have a coil spring extending between pivot pins 18 and 20 to maintain the effective link length at a constant value. Thus, if tolerances were such that considerable play might exist at the linkage joints, the tension spring would tend to eliminate this.
Such a link and spring construction has involved the expense of providing means on a pivot pin for locking the 2 parts together as Well as disposing the spring in position. As a rule, this has been accomplished by spreading the head of the pin to lock the link and spring in position.
In accordance with the present invention, link 19 consists of body 28 having apertured pivot end portions 29 and 30. Since end portions 29 and 30 are similar, it will only be necessary to describe one such end portion. Referring, for example, to end portion 29, aperture 31 has a generally circular outline. The departure from circularity is due to straight edge portions a and b which are spaced from each other and are opposite a long edge of the link. Opposite portions a and b slot 32 is provided, this slot extending from the free end of the link near one side of the link and generally along the length thereof for a substantial distance to provide exible tongue 33. Slot 32 intersects aperture 31 so that the slot and aperture merge at the region of intersection with the tongue edge providing a boundary for aperture 31.
Straight edge portions a, b and opposed edge c of tongue 33 together provide a three point grip for engaging a generally cylindrical pin, such as 20. In fact, by proper proportioning of the aperture, slot and straight portions a, b and c, las well as the outside diameter of pin 20, a rather tight grip of the link on the pin will be obtained with tongue 33 functioning as a spring member to retain the link in position.
Pivot pin 20 is smooth and does not have its head or end portion spread. The pivot pin, as illustrated in Figure 3, may be extruded from the body of the metal of member 22 or the member which is supposed to carry the pivot pin. In the case of member 16, the extrusion will be from the metal forming arm 17. Preferably the pin carrying member has enough area to provide a bearing surface for the side of the link.
As illustrated in Figure 5, the spring end of a link may be snaped over the smooth pivot pin, or in this case the extruded pivot, spring tongue 33 bearing against the outside of the pivot to maintain the link snugly in position.
It is desirable to provide means for preventing link 19 from moving oit from the pivots. The simplest means for accomplishing this is to provide a retaining finger such as 35 from the body of one of the parts between which the link extends. In this particular case, link 19 extends between member 16 and member 22. Accordingly, member 22 may conveniently have a portion thereof bent upwardly to provide tongue 35 close enough to the body of link 19 and so positioned as to keep the link properly in place.
If member 22 happened to extend in the opposite direction away from pivot 18 rather than toward it, then a portion of member 22 should be extended toward pin 18 to provide tongue 35. It is, of course, possible to strike out a tongue from portion 17 and have it so positioned as to lock the link in place.
Link 19 may be constructed of any suitable metal having some spring. Thus, soft steel will generally have suiicient spring to perform satisfactorily. It is also possible to construct the link of brass or any spring metal and in some instances it may even be possible to use plastic. It will be evident that the invention may be applied to small mechanisms in a wide variety of materials and effect substantial economies in regard to the assembly of parts.
What is claimed is:
`1. A link comprising a thin ilat strip of spring material having at least one end provided with a non-circular aperture and a slot extending longitudinally from the free end of the link past said aperture laterally oifset therefrom and extending well along into the body of said link, said slot intersecting the aperture to provide a long dat narrow tongue, the free edge of said tongue providing a boundary for said apertured portion and cooperating with the edge 3 of the apertured portion for tightly gripping a cylindrical 2. The link according to claim l wherein the edge of the link material at the aperture opposite the tongue is shaped to provide two separated straight edgessothata three-point contact may bel established.
3. In a mechanisrnhaving two vmembersrelatively movable to each other and connected by one or morelinks for transmitting motion between said members, a `link comprising a at spring body portion having aperturedends, each apertured end having the link material slotted longitudinally from the end and laterally offset from the aperture to provide a longilat spring tongue which .can be forced to widen the slotto Vpermit saidflinktobe snapped Iover a pivot zpin, each link .remaining substantiallyaat at all times and the aperture Lbeingsubstan-tially llargerrthan theslot, .each member carrying atleastione'pivotpin to have at least one link ybetween said pivot pins, eachmemberiproviding a'bearng surface for one siderof the link, said pivot pins being smoothand ,therapertured end being susceptible to sliding off'frorn a .pivot pin, one vof said l members having an integral part shaped to provide a retaining linger disposed against the bodyrof said link and being so positioned as to prevent said apertured end from sliding oft a pivot pin.
4. The construction according to claim 3 wherein each aperture in said apertured portion has at least one straight edge portion opposite the ,tongue to provide contact with a cylindrical pin at a plurality of spaced points, said contact being non-circular.
References A,Citedxinlthe Cfliet/this:patent UNITED STATES PATENTS 132,261 i LD uLaney u "Oct. 15, 1872 255,75l Zeigler Mar. 28, 1882 280,902 Blood July 10, 1883 428,612 Hutchinson May 27, l890 1,391,731 Genung Sept. 27, 1921 1,602,496 Lewis "Oct, '12, 1926 2,136,023 Russell Nov. 8, 1938 2,235,976 Best Mar. 25, 194,1