Tools for assembling retaining rings on grooved shafts, pins and the like

Sept. 5, 1961 h. erdmann 2,998,643

TOOLS FOR ASSEMBLING RETAINING RINGS ON

GROOVED SHAFTS, PINS AND THE LIKE

Filed April 23, 1959 4 Sheets-Sheet 1

<img file="US2998643A_D0001.tif" />

ATTORNEY

Sept. 5, 1961 _H. erdmann 2,998,643

TOOLS FOR ASSEMBLING RETAINING RINGS ON

GROOVED SHAFTS, PINS AND THE LIKE

Filed April 23, 1959 4 Sheets-Sheet 2

<img file="US2998643A_D0002.tif" />

FIG. ⁵

<img file="US2998643A_D0003.tif" />

ATTORNEY

Sept. 5, 1961 h. erdmann 2,998,643

TOOLS FOR ASSEMBLING RETAINING RINGS ON

GROOVED SHAFTS, PINS AND THE LIKE

Filed April 23, 1959 4 Sheets-Sheet 3

<img file="US2998643A_D0004.tif" />

ATTORNEY

Sept. 5, 1961 h. erdmann 2,998,643

TOOLS FOR ASSEMBLING RETAINING RINGS ON

GROOVED SHAFTS, PINS AND THE LIKE filed April 23, 1959 4 Sheets-Sheet 4

<img file="US2998643A_D0005.tif" />

FIG. 9

<img file="US2998643A_D0006.tif" />

ATTORNEY

United States Patent Office

2,998,643

Patented Sept. 5, 1961

2,998,643 TOOLS FOR ASSEMBLING RETAINING RINGS

ON GROOVED SHAFTS, PINS AND THE LIKE Hans Erdmann, Maplewood, N.J., assignor to Waldes

Kohinoor, Inc., Long Island City, N.Y., a corporation of New York

Filed Apr. 23, 1959, Ser. No. 808,376 12 Claims. (Cl. 29—229)

This invention relates to· improvements in tools for assembling open retaining rings on grooved shafts, pins and the like, and is more particularly directed to an improved combination retaining ring dispensing and applying tool of the general type disclosed in my prior application Serial No. 742,135, filed June 16, 1958, now patent No. 2,958,123, dated November 1, 1960.

Broadly, such a tool combines an applicator blade featuring a bifurcated or double-armed working end having a forwardly opening ring-receiving cut-out closed on its relatively under side by a retractible slide and a spring rail-type stack rod for mounting a plurality of the open rings to be assembled in a stack or column normally supported on the slide, in such a way that the tool is actuable solely by its relative movement against and away from the shaft or pin, first to effect assembly of a ring contained in the cut-out in the shaft groove and thereupon an automatic feed of the then lowermost ring on the stack to the cut-out as provides for conditioning the tool for the next assembly operation. According to my aforesaid application, retraction of the slide as enables the bifurcated working end of the applicator blade to straddle or fork the shaft or pin during the course of an assembly operation is controlled by flexing of the stack rod via one or more rings disposed thereon adjacent the one being assembled, and the working end of the applicator blade was provided with a forwardly projecting guide finger extending from one of its arms for guiding the ring into its groove. More particularly, the guide finger, by entering the groove head of the tool, served the desirable purpose of disposing the ring in the “assembly-ready” posi- 40 tion in the tool in exact alignment with the groove. Also, in a tool according to my aforesaid application, both the inner edge of the guide finger and the forward end-edge of the other arm of the applicator blade were so shaped and spaced as to make possible free retracting movement 45 of the tool from the workpiece without such movement being impeded by the just-assembled ring.

The provision of the aforesaid guide finger and the inclined end edge of the other arm of the applicator blade of course required a special design and precision manu- 50 facture thereof which increased the overall cost of tool manufacture. In addition, the projecting guide finger with its relatively sharp inner guiding edge, which is a virtual knife edge in the tool adapted to the smaller ring sizes, gave rise to objections on the part of the tool opera- 55 tors on the ground that they could cut their hands or fingers on same. Also, while functioning normally as intended, some operators, through carelessness or haste, tended to place too much reliance on the guide finger in properly relating the tool to the workpiece, as resulted in the tool becoming jammed or the ring being imperfectly assembled.

Stated broadly, a principal object of the present invention is to provide a combination retaining ring dispensing and applying tool as aforesaid which provides effective guidance of tool to workpiece, while doing away with the aforesaid guide finger and thereby the requirement of a front-end working blade construction of special shape and design, as was previously necessary to provide for free tool retraction from the workpiece following a ring assembly operation.

Another object of the invention is the provision Of a combination ring dispensing and applying tool as aforesaid which is constructed and arranged as to permit use of the ring then ready for assembly as the tool-to-workpiece guiding means.

A more particular object of the invention is the provision of a combination ring dispensing and applying tool generally as aforesaid which incorporates hand-controlled means adapted to be operated preferably just in advance of the tool being moved against the workpiece 10 for rendering the ring in the assembly-ready position in the cut-out effective as a tool-to-workpiece guide means.

More specifically, it is an object of the invention to provide, in a tool of the last stated character, a handcontrolled lever arrangement actuable to· effect relative 15 rearward shift of the rings on the stack rod disposed next adjacent the ring in the assembly-ready position in the tool cut-out, as exposes the latter ring and renders it capable of guiding the tool to the workpiece in its further movement thereagainst, as insures effective ring transfer 20 to the workpiece groove.

Yet another object of the invention is the provision of a combination ring-dispensing and applying tool incorporating a hand-controlled lever arrangement for exposing the ring of the stack then in the assembly-ready position, as 25 aforesaid, which may also be utilized as a means for retracting the slide as enables the working end of the tool applicator blade to properly fork or straddle the workpiece during the course of a ring-assembly operation.

Still another object of the invention is the provision of a combination ring-dispensing and applying tool incorporating means for exposing the ring then in the assemblyready position within the tool along its front edge whereby it may serve as a tool-to-workpiece guide means as aforesaid and which, in addition, includes provision for securely holding said ring against unintentional movement as insures its proper functioning as a guide means.

Still another object of the invention is the provision of a ring-dispensing and applying tool as aforesaid, characterized by a stack rod whose end adjacent the applicator blade, in addition to possessing the requisite flexibility in relatively forward and rearward directions as enables it to perform its automatic ring-to-cut out feed function, is also capable of exerting spring bias on the ring then disposed in the cut-out sufficient to effectively hold a ring in the assembly-ready position in the tool against unintentional movement as it performs its toolto-workpiece guiding function.

The above and other objects and features of advantage of the improved combination ring dispensing and applying tool according to the present invention will appear from the following detailed description thereof and the accompanying illustrative drawings, wherein—

FIG. 1 is aside view, partly in section, of the improved tool as herein proposed, with the tool parts in their inactive or rest position;

FIG. 2 is a broken-away, enlarged side elevation of the working-end parts of the tool prior to the same being loaded with rings;

FIG. 3 is a broken-away front view of the tool parts shown in FIG. 2;

FIG. 4 is a broken-away plan view, and FIG. 5 is a corresponding broken-away vertical section·, of the working end of the tool according to FIG. 1 shown to be 65 approaching the workpiece (grooved shaft) preparatory to performing a ring-assembly operation;

FIGS. 6 and 7 are views similar to FIGS. 4 and 5, respectively, which illustrate the manner in which the ring then in the assembly-ready position in the tool serves as 70 a tool-to-workpiece guide means when exposed for this purpose under control of the operator; and

FIGS. 8 and 9 are views corresponding to FIGS. 6

2,998,643 and 7, respectively, showing the relation of tool parts upon a ring-assembly operation having just been completed.

In common with the tool disclosed in my aforesaid earlier application Serial No. 742,135, now Patent No. 5 2,958,123, as aforesaid, the improved combination ring dispensing and applying tool of the present invention preferably utilizes a channel-shaped body part 10 capable of serving as a tool handle, such comprising a main wall 11 and top and bottom angles 12 and 13, which 10 latter are provided with confronting flanges 14, 15 which partially close the open side of the channel. Secured to the top angle 12 is a bracket 16, to the lower edge of which is affixed the horizontally disposed leg or portion of a generally L-shaped (in side view) spring rail 17 15 serving as a stack rod on which a plurality of the rings R to be assembled are threaded whereby they assume an exactly aligned position. By reference to FIG. 8 in particular, it will be seen that the rings R are of known open-ring configuration, being provided with a middle 20 lug r¹ and end lugs r² and r³, whose inner edges are formed as arcs of a common circle and hence define the effective inner edge of the ring. Also to be noted is that the arms of the ring which define the gap terminate in forwardly-extending points r⁴ and r⁵, such assuming of 25 course that the rings are turned so that their gaps face forwardly or towards the left, as in FIG. 1.

The other leg 17« of the stack rod 17 extends downwardly-vertically from the aforesaid fixed leg thereof and is devoid of securement to the handle 10 whereby 30 it may flex relatively rearwardly (to the right) from its normal unstressed position as shown in FIG. 1 to its most rearward position here shown in FIG. 9. It will be observed that the rings R mounted on the stack rod are urged towards said free end thereof as by means of a 35 follower 18 riding on the stack rod and being biased so as to press the ring stack to the left as by means of a long coil spring 19.

An applicator blade 20 is shown to be affixed at one end to the bottom angle 13 of the tool handle 10, from 40 which it inclines downwardly-forwardly and terminates in a horizontal working end 20« disposed immediately below and in general right-angular relationship with the aforesaid free end 17« of the stack rod. As best seen in FIG. 3, the working end of the applicator blade is formed 45 as two spaced arms 21, 22 which define between them an upwardly opening recess 23 (FIGS. 4 and 5) of width corresponding to the external diameter of the rings R of the stack thereof and which has a floor or bottom 24 of thickness corresponding to the axial thickness of one ring R. As best seen in FIG. 4, the forward edge of the recess bottom plate 24 is arcuate and extends on a substantially semi-circular arc, thus to provide a cut-out 25 which is open top and bottom and which further opens forwardly through the aforesaid working end, said cut-out being ₅₅adapted to receive and maintain the lowermost ring of the stack in the so-called “assembly-ready” position.

Said lowermost ring R is prevented from falling through the cut-out by a slide 26 which, in its normal position shown in FIGS. 2 and 5 to which it is biased ₆₀by means of a spring 29 (FIG. 1 only) provides a bottom support for the ring column. However, said slide is mounted for sliding retracting movement on said working end 20« of the applicator blade during the course of each assembly operation, responsive to rearward, i.e., move- gg ment away from the open end of the cut-out 25, flexing movement of the free end of the stack rod which is transmitted to the slide via some of the higher rings of the stack engaging a finger 30 projecing upwardly from the top wall of the slide, all as disclosed and claimed 70 in my aforesaid application Serial No. 742,135.

According to the present invention, a two-arm lever assembly 31 is pivotally connected to the main wall 11 of the tool handle 10 as by a pin 31« for limited rocking movement relative thereto. One arm 32 of said lever 75 assembly extends beneath said tool handle and is formed as a hand grip whose movement in upward direction is restricted by its engagement with the bottom angle 13 of said tool handle. The other arm 33 of said lever extends forwardly and terminates in an offset front part 33« disposed forwardly of and in controlling relation to a member 34. In the illustrated embodiment, such member 34 has inverted U -shape as in FIG. 3 and its two side legs 35, 36 are inclined vertically-rearwardly by a slight angle and terminate at their lower ends in presser feet 35«, 36« which rest on the upper surface of the aforesaid retracting slide 26.

According to a further feature of the invention, there is provided a rib 37 rigidly connected to both the Umember 34 and the flexible end of the stack rod 17 and serving as a connecting web or link therebetween. By virtue of its said connection to said parts, the rib 37 is of course effective to transmit movement from the Umember to the end of the stack rod, and vice versa. Also, said rib acts pressure-wise similarly to the stack rod; that is to say, if said stack rod is biased to exert downward pressure, the rib will be similarly biased. This condition is satisfied, according to the invention, by fabricating the stack rod with some extra length. That is to say, its length is greater by about Mg than its normal length, which latter would be such that the lower end of the stack rod terminates just short of the upper face line of a ring contained in the cut-out. This extra length is then taken up by securely attaching the lower end portion 17b of the stack rod, as by means of rivet 40 (FIG. 3) to the lower end of said rib 37 as aforesaid, while at the same time providing the rib with vertical dimension such that when it is held substantially vertical (as in FIG. 2, for example) by the U-member 34 to which its upper end is secured (as by rivets 42), its lower end edge 37« is substantially exactly disposed at the top line of the ring R then disposed in said cut-out 25. Considering that said stack rod 17 is extra long, its securement to the rib aforesaid has the effect of causing said stack rod to buckle slightly in a height-portion thereof disposed above the rib and, consequent thereto, it exerts downward bias on the rib 37 and more in point here, on the lower end edge 37« thereof. As will be hereinafter explained, such is utilized in holding the ring exposed along its forward edge so as to serve as a tool-to-workpiece guide means in firm position within the cut-out so that it cannot unintentionally move or turn away from its most effective guiding position.

The operation of the above described tool according to the invention may be briefly summarized as follows:

Assuming a supply of rings R to be positioned on the stack rod 17, with the lowermost ring of the stack thereof being disposed in the assembly-ready position in the cutout 25 of the applicator blade and supported from below by the slide then in its normal position as in FIGS. 4 and 5, for example, the tool is moved towards the workpiece, illustratively a grooved shaft S supported in a fixture F, in whose groove g the said ring in the assembly-ready position is to be assembled. Prior to the tool making contact with said workpiece, the operator presses grip arm 32 of the lever assembly 31 which effects limited rocking of said assembly as a whole in counterclockwise direction. Such results in the offset front end 33« of the lever arm 33, through its engagement with the U-member 34, pressing the latter backward with a slight rotational movement which is proportional in angular extent to the stroke of the grip arm 32. This rearward movement of the U-member is transmitted to the free end of the stack rod 17 and thereby to the rings immediately above the lowermost ring R of the stack thereof then occupying the assemblyready position in the cut-out 25, including the particular rings of the stack occupying the level of the slide finger 30, and finally by the latter rings to the slide 26, with the amount of such movement herein determined by the stroke of the grip arm 32. However although limited, £,998, s this rearward movement of both the free end of stack rod and slide is sufficient both to expose the forward edge portion, i.e. the pointed ends r⁴, r⁵, of the lowermost ring R in the aforesaid assembly-ready position in the cut-out 25 both from above and below, as seen in FIGS. 6 and 7, 5 for example, and also in effect to pinch or clamp the rearward edge portion of said ring between the lower end edge 37α of the rib 37 and the bottom wall of the now partially retracted slide 26.

With the grip arm 32 held firmly against the bottom io angle 13 of the tool handle or body part 11 as aforesaid, the tool is now pushed bodily forwardly until the exposed ends r⁴, r^B of said ring engage in the shaft groove g. Upon such engagement being made, the tool may now be moved positively against the shaft S, with assurance 15 that it is in proper position as to effect transfer of the ring R in the assembly-ready position aforesaid to the groove. Thus, final push movement of the tool against the shaft results in movement of said tool relative to shaft S to a position shown in FIGS. 8 and 9 and hence in com· 20 pletion of the ring-assembly operation, consequent to the cut-out edge 25, which serves as a ring abutment edge, translating the push force applied to the tool into push force on the rearward edge of said ring necessary to spring it into the groove. 25

The advisability if not also the necessity of holding the ring R in the assembly-ready position when partially exposed as aforesaid against movement becomes apparent from FIG. 7, which illustrates that the rings above same have moved rearwardly thereof and the slide 26 is provid- 30 ing only partial support therefor from below. The desirable ring-holding action is effectively supplied by the downward spring bias imparted on the middle portion of the ring by the lower end edge 37α of the rib 37, as results from the aforesaid oversizing of the free end of the 35 stack rod 17 and its buckling when affixed to said rib in the manner described above.

A stack rod having a purposeful increase in length which is taken up as aforesaid yields another important advantage. Formerly, the stack rod had to be cut to ex- 40 act size with very small permissible tolerances. In explanation, if the stack rod were even slightly longer than required, it would impede the transfer movement of ring from cut-out to shaft groove; and if it were shorter, which can also happen through wear of its end edge, -the ring ., next above the one being assembled tends to follow the latter ring in its assembly by friction, with the result that the ring column is likely to become jammed. However, by the present proposal, increased length does not matter; in fact, the stack rod is puipiosely formed long, and then it is buckled to the degree that its lower end edge takes the exact position in which the stack rod operates most efficiently, which may be simply achieved by the action of the U-member 34 in determining the free end-edge position of the stack rod.

It is also to be observed that the U-member 34 accomplishes a number of useful purposes. Basically of course, it serves to move the stack rod and the rings above the ring R in the assembly-ready position by a predetermined amount as exposes said latter ring for guidance purposes; it also, as above explained, mounts the rib 37 in position such that its lower end edge exerts downward pressure on the ring in the assembly-ready position when the latter is exposed as aforesaid; and also-, as a result of its side arms resting on the top surface of the slide 26, it fixes the level of the lower end edge of the stack rod so that it can ⁶⁵never enter the opening of the ring disposed in the ring cut-out 25.

Of course, instead of the lower ends or feet 35α, 36α of the U-member legs 35, 36 resting on the top surface of γθ the slide 26 as described above, said feet may be disposed to rest directly on the upper surfaces of the arms 21, 22 of the working end of the applicator blade, for example, just forwardly of the slide. Also, by proper design of the parts, said U-member may be employed to directly actu- 75

643 ate the slide 26 in rearward direction, as by arranging the feet 35α, 36α thereof to engage with the front edge of its top wall, should it be found advisable or necessary to impart -a positive, first-stage retracting movement to the slide through such means, rather than via the rings disposed between -the stack rod and the slide finger 30.

Without further analysis, it will be appreciated that the combination retaining ring dispensing and applying tool according to the invention achieves the desirable objectives -therefor as set forth in the foregoing. More particularly, the -tool of the invention makes unnecessary both the precisely dimensioned and sharp-edged guide finger and the special design of the working end of the applicator blade for insuring free retraction of the tool following each assembly operation which characterized -the tool of my aforesaid application Serial No. 742,135, now Patent No. 2,958,123 as aforesaid. Also, by virtue of the fact that the operator is required to perform what may be termed a first-stage or preliminary assembly operation, i.e. that of depressing the grip arm 32 of the lever assembly 31 in order to expose the lowermost ring of the stack thereof then in the assembly-ready position in the cut-out, he is not likely to speed up the assembly operation beyond the capability of -the tool as he was prone to do in using the tool provided with the guide finger, with the result that a more certain and accurate ring assembly operation results, thus minimizing the likelihood of the ring and/or tool becoming jammed due to too hurried or too careless operation.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the -above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.