US1378222A

US1378222A - Shifter-fork plunger

Info

Publication number: US1378222A
Application number: US406157A
Authority: US
Inventors: Maximilian C Frins
Original assignee: International Motor Co
Current assignee: International Motor Co
Priority date: 1920-08-26
Filing date: 1920-08-26
Publication date: 1921-05-17
Anticipated expiration: 1938-05-17

Description

' Patented May 17, 1921.

I d? m I MW M a III) UNYITED'STATES PATENT OFFICE.-

MAXIMILIAN C. FBINS, OF NEW YORK N. Y., ASSIGNOR TO INGWATIONAL MOTOR COMPANY, QF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

SKIPPER-FORK PLUNGER.

Specification of Letters Patent.

Patented May 1'7, 1921.

Applicatlon filed August 26, 19 20. Serial No. 406,157.

To all whom it may concern:

Be it known that I, MAXIMILIAN C. FRINS, a citizen of the United States, residing in the borough of Manhattan of the city of New York, in the State of New York, have plunger. for positioning shifter forks and also to an improved association thereof with a positioning1 groove for the'fork'cut transversely in e sup orting shaft on which the fork slides. eretofor'e, plunge'rs for the purpose noted haveusually been formed with a generally conical end adapt ed to seat in a similar recess in the shaft or in a transverse groove cut in the shaft. The bearing end for the plunger hasfheretofore usually afforded acne-point "support with the result that upon shifting of the fork the nose of the plunger would nick the groove at its edge and ultimately ream a longitudinal channel in the shaft along the path of movement of the plunger.-

This nicking has resulted in a breaking down of the holding wall of the oove to such an extent that the fork is o ten accidentally shaken from its position when the plunger rides loosely out of the nicked groove. Further, the shaft itself is marred and little resistance offered to the free sliding of the fork. By the improved construction it is sought toprovide a plunger which is of such character as to prevent the positioning groove from being nicked or worn to any appreciable extent and to rest on the shaft wit a relatively broad bearing surface so as to wear it'uniformly, if at. all, and not mar its exterior surfacel In accordance with the invention the nose of-the plunger is formed by tapering it at oppoing surface conforming to the curvature of I the shaft. The entering groove for the side walls and a site sides leaving a transverse blunt nosewhich is milled out concentrically with the shaft 'so as to. form a broad and long bearis similarly formed with tapered In the preferred form of the invention theplunger is held against rotative movement within the hub of the fork by means of a positioning. in which has a slotted engagement with tiie plunger. 7

7 Reference is now to be had to the accompanying drawing fora detailed description of one embodiment of the invention, in

which Figure 1 is a view in elevation'of a shifter fork of approved type and in section through the hub thereof and the improved positioning plunger, the nose of the plunger being indicated in elevation. i

Fig. 2 is a view in transverse section taken through the hub of thefork shown in Fig. 1 along the plane of the'line 2-2 and looking in thedirection of thearrows,.the shaft and plunger being'shown in plan.

The fork a which-may be of any approved form may be cast as usual with an elongated hub a, through whichpasses a' supporting shaft b along which the fork is slidin amanner' which will be understood. The position of the fork with its gear is, of

course, determined by the. position in which it is arrestedin its movement along the shaft 1). For the purpose of fixing this position and indicating to the operator whena desired position .is reached, it is usual to mount with the hub a a positioning plungervindicated at c and adapted to cooperate with notches or the like, indicated at b. The'plun'geis heretofore employed have "been objectionable in that "their; I I

noses have usually been formed to afford such a hearing; as would nick the positionindeed, have a tendency. to cut a groove along the shaft in the path of travel of the plunger with the fork. The present invention seeks to provide .an improved plunger which is of such form as to eliminate any ing recess or notch in the shaft and would,

reaming action by its-nose on any metal with which it engages. Accordingly, the plunger 0 at its inner end is tapered at Oposite sides, as indicated at c, c terminatmg in a blunt nose,indicated atfc The nose 0 is milled out transversely, as indithe supporting shaft 1). The entering groove cated at 0" along a line substantially concentric. in curvat-urewith the curvature of ally similar form to the end of the plunger verse notches 6', although in some construcc as described in that this notch has opposed side walls 6 and a broad bottom [2 the form and dimensions being such as toreceive snugly the tapered nose of the plunger. The plunger 0 may be hollow for a portion of its length to receive a spring 03 which may seat on a plate 6 held against movements by a cotter pin f which may pass .through the extension a of the hub a in which the plunger is positioned. The cotter pin f rests in opposed slots 0 cut in the side walls of the plunger adjacent its end so as to permit axial movement of the plunger.

In operation it will be evident that the plunger 0 is pressed yieldingly into=engagement with the shaft 2) at all times under the influence of the spring ol. When the fork a is slid along the shaft by any usual means the plunger 0, of course, rides out of the notch b with whichits nose engages, moving axially against the pressure of the spring (1. In riding out of the notch b it is evident that one of the tapered side walls 0', c

of the nose of the plunger 0 will remain in engagement with one of the taperedside walls b of the notch until the end of the plunger passes out of the notch when the edge of the curved end 0 of the plunger will have a moment to engage the edge of one of the side walls 6 At that instant there will be a line of contact of substantial length between the two edges. This kind of contact will prevent any nicking or undue wear on the metal of the shaft. When the plunger finally rides on to the exterior surface of theshaft b the curved end 0 will rest snugly i on the shaft and afford a relatively broad and long bearing surface for the plunger.

The Wear occasioned by the plunger on the shaft will be negligible and, of course, uniform. There will be no tendency for the pluhger to groove or nick the shaft at any 7 point. The engagement of. the cotter pin with the slot 0 in the'plunger will maintain it at alltimes in proper relation to the transtions it may be found unnecessaryto provide any such positioning devices.

I claim as my invention:

1. Asan article of manufacture, a shifter fork plunger having a nose formed with oppositely tapered side walls terminating in a blunt nose curved transversely.

2. As an article of manufacture, a shifter fork plunger formed at one end with oppofork and having oneend formed with oppositely tapered slots terminatin in a fiatblunt nose curved transversely, said shaft being prov1ded with cooperating grooves cut transversely to the axis of the shaft and formed 5 similarly to the nose of the plunger.

5. In combination with a shifter fork and a supporting shaft on which the fork is slidably mounted, a plunger carried with the fork and having one endformed with oppositely tapered slots terminating in a flat blunt nose curved transversely along a line concentric to the shaft, said shaft being pro- .vided with cooperating grooves cut transversely to the axis of the shaft and formed with opposed side walls tapered similarly to the tapered nose of the plunger and with a broad flat bottom to receivethe flat nose of the plunger.

This specification signed this 20th day of August, A. D. 1920.

MAXIMILIAN C. F RINS.