US 3327377 A
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Description (OCR text may contain errors)
June 1967 E. 1.. GERMAN SIZE ADJUSTABLE TOOL FOR REMOVING AND INSTALLING CAM SHAFT BUSHINGS OF DIFFERENT SIZES 3 Sheets-Sheet 1 Filed Sept. 7, 1965 INVENTOR age/144W grwH- 4651 7 June 27, 1967 E. L. GERMAN 3,327,377
SIZE ADJUSTABLE TOOL FOR REMOVING AND INSTALLING CAM SHAFT BUSHINGS OF DIFFERENT SIZES Filed Sept. 7. 1965 5 Sheets-Sheet 2 I N VENTOR. 50144420 .4. GZ-PMA/V BY H-QNL A as/v7 June 27, 1967 E. L. GERMAN 3,327,377
SIZE ADJUSTABLE TOOL FOR REMOVING AND INSTALLING CAM SHAFT BUSHINGS OF DIFFERENT SIZES Filed Sept. '7, 1965 5 Sheets-Sheet 5 INVENTOK 519a. 39c 43 EDWfl/QD L. GEE/I44 United States Patent 3,327,377 SIZE ADJUSTABLE TOOL FOR REMOVING AND INSTALLING CAM SHAFT BUSHINGS ()F DIF- FERENT SIZES Edward L. German, 933 W. th St., Corona, Calif. 91720 Filed Sept. 7, 1965, Ser. No. 485,261 3 Claims. (Cl. 29263) This invention relates to an improved tool especially useful for the removal of old bushings from, and the insertion of new bushings in, hard to reach bearing sites. In particular, the invention relates to such a tool having primary usefulness for the removal of bushings from the cam shaft bearings of internal combustion engines and the reverse procedure of inserting bushings therein.
The difficulty of removing used bushings from automobile cam shaft bearings, and the even greater difliculty of inserting new bushings in their places, is well known to mechanics and others skilled in the automotive arts. At present, the principal method of removing old bushings from cam shaft bearings is to drive them out with a hammer and chisel, and the insertion of new bushings is accomplished by means of a hammer and block. These methods are antiquated and diificult to apply, their shortcomings being well known to automobile mechanics and others faced with the necessity of repairing and maintaining internal combustion engines. Chief among such shortcomings are the difficulties of reaching the bushing sites with hand tools such as chisels, hammers, etc.; the time consuming nature of a bushing replacement job when done with these tools; the frequent distortion of new bushings resulting from the use of such tools with consequent low spot formation as a result of line boring operations thereby made necessary; etc.
I have now invented a structurally simple and inexpensive-to-produce tool, adapted to greatly facilitate the removal of old cam shaft bushings from their bearing seats in internal combustion engine crankcases and the substitution of new ones in their places. The use of my new tool, as will be seen, makes it possible to so remove and install cam shaft bushings without experiencing the above-noted, and other, difiiculties of the archaic, but still much used, hand tool bushing removal and placement methods. Furthermore, the tool can be made expandably adjustable to suit it for use on a variety of engines with variously sized cam shaft bearings.
More specifically, my tool, in its preferred form, comprises a puller rod adapted to extend through bearing openings in an engine crankcase; at least one cylindricallyshaped and radially expandable mandrel which is slidable on the puller rod and can be readily adapted, by virtue of its radial expandability, to fit differently sized bushings for said bearing openings; and cooperating rod pulling, rod locking and mandrel locking means, subsequently to be described in detail. The tool is designed for installation in an engine crankcase with the puller rod extending through bearing openings therein, at least one of the expandable mandrels fitted within a bushing to be removed from, or inserted in, one of the bearing openings and suitable mandrel locking means (to prevent relative movement between the mandrel and rod), rod rotation preventing means and rod pulling means in place whereby actuation of the rod pulling means results in a steady forcing of the rod, mandrel and bushing in the proper direction to remove a seated bushing from said bearing opening, or insert such a bushing therein, with a minimum of effort and skill. The structural and functional details of the tool and its unique expandable mandrel, will, as previously indicated, be disclosed in detail hereinafter.
It is thus a principal object of this invention to provide a structurally simple tool, inexpensive to produce, adapted to reach and effectively function at cam bushing sites in internal combustion engines to bring about the quick and easy removal of old cam bushings from their bearing seats and the installation of new bushings in place therein.
It is another object of the invention to provide such a tool capable of effectuating the simultaneous removal of a plurality of old cam bushings from an internal combustion engine crankcase, and the subsequent simultaneous replacement of the bushings with new ones.
It is still another object of the invention to provide such a tool capable of effectuating cam bushing removal and installation operations in internal combustion engines with minimal risk of resultant bushing distortion.
It is yet another object of the invention to provide such a tool adaptable for the servicing of variously sized cam bushings without the necessity of interchanging any of the tool parts or accessories in the process.
It is another object of the invention to provide a means for removing internal combustion engine cam bushings from their bearing seats, and for inserting new bushings therein, without creating localized high friction areas as a result of circumferential deviations between meeting bushing and bearing surfaces.
Other objects, features and advantages of my invention will appear in the light of the following description considered in conjunction with the accompanying drawings, of which:
FIGURE 1 is a perspective view showing the disassembled parts of a basic tool in accordance with this invention, the view being somewhat in the nature of an exploded view and showing the manner and order in which the parts of the tool are assembled.
FIGURE 2 is a fragmentary view, mostly in longitudinal section, through the crankcase of an internal combustion engine showing my new tool in working position for the insertion of cam bushings in the cam shaft bearings of the engine and depicting intermediate and final phases of the bushing insertion operation.
FIGURE 3 is a view similar to the FIGURE 2 view, but showing the tool in cam bushing removal position, one bushing being shown after its complete removal by the tool and the other being depicted in partially removed Status.
FIGURE 4 is an enlarged, fragmentary, cross sectional view of the engine crankcase with the tool in operating position therein, taken along line 4-4 of FIGURE 2 but showing an accessory locking member in a position other than its FIGURE 2 position, the latter being contrastingly depicted in phantom outline form.
FIGURE 5 is an enlarged, fragmentary view, mostly in cross section, of the crankcase and tool functionally disposed therein, taken along line 5-5 of FIGURE 3.
FIGURE 6 is a fragmentary view, mostly in longitudinal section, illustrating the way in which the tool engages a bushing when serving in its bushing inserting capacity, taken along line 6-6 of FIGURE 5 but showing relative positions of the bushing, tool parts and crankcase journal different from those of FIGURE 5.
FIGURE 7 is a side elevation, drawn to a larger scale than any of FIGURES 1 through 6, of a rider assembly for a modified version of my new tool.
FIGURE 8 is a perspective view, drawn to still another scale, of the parts of the rider assembly in spaced-apart relationship along a common line of axis, the parts being so distributed as to demonstrate the order and manner of their assembly.
FIGURE 9 is an enlarged cross sectional view of the rider assembly, taken along line 99 of FIGURE 7.
FIGURE 10 is a view, mostly in longitudinal section,
U of the rider assembly, taken along line 10 of FIG- URE 7.
Proceeding now to a detailed consideration of the drawings, attention is first directed to FIGURES 1 through 6 which illustrate and show in working environment an embodiment, shown generally at 1, of my new tool in one of its most basic forms. The parts of the tool, as shown in FIGURE 1, are a round rod 17, a bushing mandrel 19, a thrust disc 23, a thrust bearings 25, a nut 27 and a locking fork 21. Rod 17 is made of a hard and tough metal such as, for example, a tool steel of about 4142 hardness and tensile strength of 250,000 p.s.i, The rod construction does not require this particular material, however, and materials equivalently suitable for the purpose will readily suggest themselves to those skilled in the art. Rod 17 has a threaded portion, or shank, 17a at one end, and is characterized throughout its remaining length by the evenly spaced distribution of a plurality of pairs of diametrically opposite, parallel bottomed and equally dimensioned slots 17b thereon. The rod is so sized, both diameterand length-wise, as to fit easily through the cam shaft bearings of any internal combustion engine on which it is intended for use and pass completely through the engine crankcase.
The manner in which rod 17 extends through such cam shaft bearings is illustrated by FIGURES 2 and 3, each of which shows a crankcase 3 of an internal combustion engine having cam shaft bearings 3a, 3b, 3c and 3d through which the rod passes. Crankcase 3 is not intended to represent the crankcase of any specific engine, but only to typify the internal combustion engine environment within which tool 1 is adapted to function. As previously indicated, cam shaft bearings vary in size among the many available models and brands of internal combustion engines, and even, in many cases, within a single engine itself. As will be evident, however, the manner of use and functioning of tool 1 is the same, regardless of cam shaft bearing size, and hence the pictured use of the tool in the crankcase environment of the drawings is more than an adequate teaching of its use in any internal combustion engine.
Mandrel 19, thrust disc 23 and thrust bearing 25 are all center-apertured to fit on rod 17 in loosely sliding relationship; nut 27 is so tapped and threaded as to mate with shank 17a of the rod in threadable relationship; and fork lock 21 has two prongs 21a and 211) so spaced and dimensioned as to permit their loosely sliding fit into any pair of diametrically opposite slots 17!) in rod 17 in the manner shown in the drawings, particularly FIGURES 4 and 5. While tool 1 has so far been discussed in terms suggestive of the presence and use of only one mandrel, any suitable number of such mandrels can be employed, the number in use at any given time depending generally upon the number of cam hearings to be serviced, although these need be no correlation between the number of mandrels in use and the number of serviced bearings. FIG- URES 2 and 3 demonstrate plural mandrel usage of the tool in which all involved mandrels are of equivalent size and configuration. The mandrels, four in each figure, are structurally similar to both each other and the FIGURE 1 mandrel. For this reason, and to avoid undue proliferation of numbers on the drawings, all mandrels of FIG- URES l, 2 and 3 are identically denoted by the reference numeral 19.
Mandrel 19 has several useful functions, as will-subsequently appear. In somewhat related vein, diversely sized mandrels can be used concurrently, consecutively, on different engines, or in any other way as working parts of my new tool. Such multi-mandrel-size usage is readily accomplished with a common puller rod (of which rod 17 is typal) and an accompanying assortment of differently-sized complementary mandrels.
As will now be clear, mandrels can be interchangeably employed on the puller rod of my tool in homogeneouslysized combination, as shown in FIGURES 2 and 3, or in a mixed-sized group, such as an engine having more than one cam shaft bearing size might require. It, of course, goes without saying that the reach of my invention encompasses the use of any sized mandrel, either alone or in combination with one or more others, consistent with proper functioning of my new tool as taught herein.
Tool 1 has, as previously indicated, two primary functions, these being (1) the removal of old cam bushings from their hearing seats in internal combustion engines and (2) the insertion of new bushings in their places. The use of the tool for the second of these functions, the insertion of the. new bushings, is illustrated by FIG- URE 2, and its use for the first, or bushing removal function, by FIGURE 3. Considering first the bushing insertion operation (typically employed for the replacement of worn or damaged bushings), the tool positioning, orientation and manner of use for accomplishing this are believed clearly evident from FIGURE 2. Briefly, the tool is positioned, or installed, for use by passing rod 17 through bearings 3a, 3b, 3c and 3d of crankcase 3 and sliding four mandrels 19, in proper longitudinal orientation, to properly spaced positions thereon.
Mandrels 19, as the drawings illustrate, are of round cross section and generally cylindrical shape, each having a concentric, axially aligned, center passageway, previously mentioned, of such size as to admit rod 17 in loosely sliding relationship. The outer diameter of the mandrel is, for most of its length, so sized as to assure a snug fitting, but nonbinding, engagement with a particularly sized cam bushing for a purpose subsequently appearing. The resulting mandrel-bushing interfit is well illustrated by the drawings, and especially FIGURE 2, which shows two bushings 9 and 11, hereinafter referred to as new bushings 9 and 11, respectively engaged with two mandrels in the above-indicated manner.
The mandrels 19 are each characterized by the presence of a radial flange 19a at one end, the flange being of such diameter as to coaxially fit, in loosely sliding rela tionship, into any of the crankcase 3 bearings. While the flange-bearing interfit relationship is pictorially depicted in FIGURE 2 (see the two end mandrels disposed within the two crankcase wall bearings), the interfit tolerance is there exaggerated for clarity of illustration. The actual tolerance is much tighter than indicate-d but not so tight as to create a danger of binding between the interfitting parts.
Mandrel flange 19a has several useful purposes, one of which is to serve as a support and axially aligning member for rod 17 in a bushing-free crankcase, such as a new one in which no bushings have yet been installed or a used one from which old bushings have been removed. This support function is exemplified in FIG- URE 2, which shows the rod supported at each end by a mandrel appropriately positioned in an end bearing of the crankcase. It will be obvious that such rod support is not necessary where more than one seated bushing is present in the crankcase since it is then possible to support and align rod 17 with mandrels mounted within the seated bushings or, to express it another way, mated with the bushings in the previously indicated manner. Where, however, there is only one seated bushing in the crankcase, the rod can be supported at that point by a mandrel mated therewith and at a second point by another mandrel positioned, and flange-centered, within a bushing-free bearing in the just-described, and drawing-illustrated, fashion. As will be obvious from this discussion of the several ways in which rod 17 can be supported by mandrels 19, the rod, in all cases, passes through the concentric passageway in the mandrel to receive its support therefrom.
Where a mandrel is mated with a seated bushing for rod support purposes, or with an unseated bushing for punposes hereinafter disclosed, it is preferably fully inserted in the bushing opening, by which is meant insertion. to contact of its radial flange therewith. This condition of full mandrel insertability is doubly illustrated in FIG- URE 2 which shows two mandrels respectively mated with new bushings 9 and 11.
It should now be apparent that rod 17 is supported and aligned within crankcase 3, for purposes of this invention, by means of at least two mandrels 19, through which it passes, stationed at bearing sites within the crankcase. It will also be apparent, particularly in view of the fact that, as we have seen, the mandrels can be employed for rod support purposes regardless of whether any or all of the crankcase bearings are occupied by bushings, that a variety of mandrel position, orientation, and spacing arrangements and combinations will serve the aforesaid rod support purposes. A suitable mandrel support arrangement or combination for any given situation or purpose will readily suggest itself to one skilled in the art having knowledge of the present teachings. Suffice it to say, in conclusion, that while any two points of mandrel support for rod 17 within the crankcase will serve the intended purpose, it is generally true that the greater the separation between the points, the more stable will be the support and the better will be the alignment of the rod.
Returning now to the discussion of the use of tool 1 in its FIGURE 2 cam bushing insertion capacity, rod 17 is passed through bearings 3a, 3b, 3c and 3a (which are, of course, in axial alignment) and four mandrels are positioned, properly spaced and oriented as shown, on the rod, as a first step of the cam bushing insertion procedure. The two end mandrels serve to support the rod in proper alignment within the crankcase, for which purpose they are positioned as shown with their flanges respectively inserted within end bearings 3a and 3d. The rod is positionally oriented so that its threaded end 1711 protrudes through the bearing in the right wall of crankcase 3 as seen in FIGURE 2.
After rod 17 has been positioned in bearings 3a, 3b, 3c and 3d, thrust disc 23 is placed on the threaded end of the rod and brought flush against the outer surface 3e of the crankcase wall; thrust bearing 25 is placed on the rod adjacent thrust disc 23; and nut 27 is screwed on the threaded end of the rod to the outer face of thrust bearing 25. The rod is now in its proper starting position for tool use.
It will be apparent that new cam bushings 9 and 11 are placed on rod 17 in proper positions for subsequent insertion within bearings 3b and 3c, respectively, during the above-described assembly operation. The time, spacing, and other, particulars of so placing the bushings on the rod in proper positional relationship to these hearings will be obvious to those skilled in the art and need not be detailed here.
After tool 1 has been installed in crankcase 3 with new bushings 9 and 11 properly positioned on rod 17, the two middle mandrels of FIGURE 2 are inserted to full mating relationship in new bushings 9 and 11, respectively, as shown. As a final step in the assembly of the tool for bushing insertion use, the two prongs of a locking fork 21 are hand-inserted upwardly into the pair of diametrically opposite slots 1712 on rod 17 most closely adjacent the flange end of a bushing-mounted mandrel positioned with its mounted bushing as close as possible to one of the crankcase bearing openings without actually contacting the bearing itself. The locking fork is preferably pushed to full engagement of its prongs with the slots, as a result of which it understraddles the rod in the manner illustrated in FIGURES 2, 3, 5 and 6.
The locking fork, as the drawings show, is simply a fork-like accessory having a main fork portion with two flat prongs, previously identified as prongs 21a and 21b, and a handle 210 which inclines away from the fork portion at a relatively shallow angle, preferably of about 8 or 10 degrees. The handle is angled to permit its easy grasp for fork handling purposes after bushing insertion use of my tool as taught herein. It will presently be seen that a fork handle not so angled is in close crankcase partition adjacency after such use, thus making the fork too difiicultly accessible for convenient reach. For essentially the same reason that its handle is angled, the fork is installed for use in the drawing-illustrated manner with its handle angling away from the bushing-mounted mandrel near the flange end of which it is positioned. The fork handle angle can, of course, vary from the above-indicated range so long as it is adequate for the intended purpose. Locking fork 21 is, in its illustrated form, of flat, metallic, construction but it can be of alternative design or configuration if desired. For example, the fork can have a round, or other than flat, handle of metal, plastic, wood, composite material, etc., in lieu of the flat handle of the drawings.
While FIGURE 2 shows two locking forks mated with rod 17 in the above-described manner, only one will ordinarily be so disposed at any given time since the fork prongs must fit relatively loosely into the rod slots to permit hand positioning of the fork as described, thus permitting the fork to drop out of place unless manually held until friction-induced to stay in a manner hereinafter described. It is, of course, within the functional scope of my invention to simultaneously engage two or more locking forks with slotted rod 17 for the concurrent insertion of a like number of bushings in crankcase cam shaft bearings but it is generally much simpler and more contributive to effectual tool use to seat only one bushing, rather than several, at a time. The reason for this is that the troublesome necessity of manually holding several locking forks in their properly slot-mated positions on rod 17 is thereby obviated.
As in the case of mandrel 19, any suitable number of locking forks can be accessory to, and used separately or jointly in combination with, rod 17 within the scope of this invention. Here, the situation is somewhat simpler than the mandrel situation, however, since my new tool will, as presently contemplated, typically comprise a set of parts including a common slotted rod and a plurality of forks which, because of their identity of purpose (mating cooperation with the rod), will all be of the same size.
Returning now to consideration of the bushing insertion applicability of my new tool, after the locking fork 21 has been placed in the above-indicated position of rod 17 understraddle adjacent the flanged end of a bushingmounted mandrel, the geometric relationship of the involved parts is similar to that illustrated in the left part of FIGURE 2 where new bushing 9 is shown mounted on a mandrel in approaching proximity to bearing 3b. The tool is now ready for use in its bushing insertion capacity and nut 27 is turned in the tightening direction on the threaded end 17a of rod 17 to initiate the necessary procedure. The tightening direction of nut 27 on rod 17 can be either clockwise or counterclockwise but, as presently contemplated, is preferably the former since that represents the more commonly occurring of the two possible threaded relationships. Nut 27 is turned, or, as it will sometimes hereinafter be expressed, tightened, on the threaded shank of rod 17 with a wrench of any suitable type, such a wrench being symbolically represented in phantom outline at 45 on FIGURES 2 and 3. During the tightening procedure, the nut is prevented from axial movement along the rod by the resistance of the immovable crankcase acting through thrust bearing 25, as a result of which the rod itself is caused to move from left to right, as seen in FIGURE 2, along its line of axis.
As rod 17 advances to the right under the moving influence of turning nut 27, the presence of the locking fork 21 adjacent the mandrel on which the bushing to be inserted in its bearing seat (hereinafter referred to as the new bushing) is mounted prevents rearward migration of the mandrel along the rod. The new bushing and the mandrel on which it is mounted thus ride forwardly in fixed position on the rod as it advances. The rod advancement soon brings the forward face of the new bushing to flanking adjacency with the bore of its destination bearing (hereinafter referred to simply as the bearing). Continued tightening of nut 27 after the new bushing has come even with the bearing bore, or opening, forces the bushing into the opening and, at the same time, subjects it to rearwardly directed pressure because of the tight friction fit between the bushing and bearing. While the tightness of the friction fit has not been antecedently discussed herein, this was not necessary since such tightness is a mater of common knowledge and its existence is clearly, if indirectly, evidenced by the above-discussed difficulties of removing cam bushings from, and inserting them in, cranckcase bearings, which difficulties are, themselves, evidenced by the present invention of a tool to greatly alleviate them.
The rearwardly directed pressure on the new bushing resulted from its forced entry into the bearing is transmitted to the locking fork rearwardly adjacent the mandrel on which said bushing is mounted (hereinafter referred to as the support mandrel) through the flange of said mandrel. The pressure thereafter holds the locking fork firmly in place, although prior to its existence the fork prongs were, as previously indicated, so loosely engaged with their mating slots in rod 17 as to require manual holding of the fork to keep it from falling. Such looseness of fork fit is not, however, critical, and the fork prongs can fit into the rod slots with any degree of tightness consistent with proper usage of the fork as taught herein.
After the new bushing has been forced into the bearing opening in the described manner, nut 27 is further tightened until the bushing is pulled to its fully seated position therein as exemplified by the position of new bushing 11 on FIGURE 2. During the nut tightening procedure, excessive rotation of rod 17 on its axis is prevented by the jamming of the end of handle 210 of the locking fork adjacent the support mandrel against an inner wall of crankcase 3, as illustrated by FIGURE 4. In FIGURE 4 the starting position of the fork is shown in phantom outline and its direction of rotation therefrom to the jammed-handle position is indicated by directional arrow means. The fact that the locking fork rotates from a free-handle starting position to its jammed-handle position will be apparent from an understanding of the mechanical operating particulars of my tool, as explained herein. However, the fork starting position can vary from that shown on FIGURE 4 to any position within the arc of fork travel there indicated and can even be adjusted to coincide with its jammed-handle position if desired. The fork starting position adjustability is made possible by the loosely sliding fit of rod 17 in its support, and other cooperating, mandrels whereby it (the rod) can be easily rotated to adjust its slots 17b (and hence the fork when engaged therewith) to any desired angle. When the fork is engaged with the rod, the range of rod rotation is, of course, limited to the angular range of movement of the fork handle within the crankcase. The vertically parallel orientation of the rod slots on the drawings was selected primarily for convenience of illustration and is not necessarily intended to represent a preferred rod slot starting position.
It will be apparent from the foregoing that the locking fork serves a dual purpose, to wit, the maintenance of a bushing-mounted mandrel in fixed position relative to the puller rod (the rod on which it is mounted, as exemplified by rod 17) when those parts are in use for purposes of this invention, and the prevention of excessive puller rod rotation during such use. It will be obvious that puller rod rotation during use obviates, or at least sharply curtails, the effectiveness of the tools performance since this results in mere Wheel spinning with little or no horizontal rod movement of the type required for such performance.
The use of my tool in the described way accomplishes the rapid and substantially effortless insertion of a cam bushing in its bearing seat. Furthermore, the seated bushing is properly aligned and free from deformation of the type sometimes resulting from the use of conventional bushing insertion methods. Those skilled in the art will not, of course, have any difficulty in determining when the bushing is fully inserted in its bearing seat.
After the new bushing has been seated in the bearing, nut 27 is loosened and rod 17 is backed far enough to reiieve the pressure on the locking fork and permit its disengagement from the rod. Following disengagement of the fork, the tool is again ready for use and can be reset for the insertion of another properly mandrelmounted and rod-positioned bushing in accordance with the above-described procedure. The bushing insertion procedure can be repeated as often as necessary to seat any desired number of new bushings in the crankcase bearings.
It will, of course, be apparent that two or more bushings can be inserted simultaneously in their separate bearings by means of my new tool if the slots in the puller rod are appropriately spaced for the purpose. Or, the tool could be so set up that one bushing is being partially inserted while another is pulled to full insertion with the tightening nut exemplified by not 27 of the drawings. From these few examples of variant Ways of utilizing my new tool for bushing insertion purpose, it will be clear, as previously indicated, that the tool is not limited to any particular use technique.
As will, of course, be obvious, any equivalent tightening means can be substituted for the nut and Wrench combination shown in the drawings. Thus, it is within the scope of the invention to employ a wing nut, or any other equivalent means, in lieu of nut 27 of the drawingillustrated embodiment of my tool. The same thing, relative to the substitution of equivalents, is true with respect to the various other parts of the tool.
Finally, relative to the bushing insertion utility of the pictured embodiment of my tool, after all of the bushings to be inserted have been pulled into their bearing seats in accordance with the above-described procedure, the tool is disassembled and removed from crankcase 3 by unscrewing and taking nut 27 from the threaded end of rod 17 and then pulling the rod out of the crankcase, appropriately removing the mandrels from the rod during its extraction.
Turning now to the other principal function of my new tool, namely, the removal of cam bushings from their bearing seats, attention is first directed to FIGURE 3 which illustrates this phase of the tool use. The crankcase of FIGURE 2., that is, crankcase 3, is likewise shown in FIGURE 3, except that in the latter it is depicted as being in need of bushing removal, and in the former of bushing insertion, servicing. As FIGURE 3 makes clear, the tool is installed with its puller rod supported and aligned within the crankcase, and passing through all of the bearing openings, in the same general way for bushing removal as for bushing insertion use. Thus, the rod is supported at its two ends within bearings 3a and 3d, respectively, by means of two mandrels 19, similarly for the former as for the latter purpose. While the mandrel supporting the nonthreaded end of rod 17 in bearing 3a has its flanged end directionally reversed in FIGURE 3 from its counterpart mandrel in FIGURE 2, this is of no significance since only the mandrel flange contacts the bearing wall and the mandrel will therefore function properly so long as its flange, regardless of how, is disposed within the bearing opening. This difference between FIG- URES 2 and 3 is incorporated merely to illustrate a small aspect of the herein-stressed use versatility of my tool. Besides having its puller rod installed for use similarly for bushing removal as for bushing insertion purposes, the pictured embodiment of my tool has thrust disc 23, thrust bearing 25 and nut 27 similarly positioned for either use contingency. Once the tool is properly installed for the bushing removal operation, it is thereafter employed in essentially the same way as it is for bushing insertion use. Thus, for bushing removal, as for bushing insertion applicability, nut 27 is turned in the tightening direction on rod 17 to thereby force the rod to advance from left to right, as seen on FIGURE 3. As the rod so advances, any mandrel adjacent any bushing to be removed (two such bearings being shown at 13 and 15 on FIGURE 3 and hereinafter identified as old bushings 13 and 15, respectively) forces the bushing gradually to the right until it is clear of its bearing seat.
The mandrel exerting pressure on the old bushing is prevented from rearward movement relative to rod 17 by the presence of a previously positioned locking fork 21 in understraddle engagement with the rod at the aft end of the mandrel, similarly to the way in which the mandrel is prevented from relative rearward movement during the bushing insertion operation. The same kind of pressure is here exerted against the fork, through the intervening mandrel, by the resistance of the old bushing to removal from its tight fitting bearing seat, as is exerted against the fork to keep it in place during the bushing insertion operation. However, the mandrel is oriented differently from the way in which it is oriented for bushing insertion purposes, as explained below and will be evident from a comparison of FIGURES 2 and 3.
As will by now be evident, the principal difference between the ways in which the tool is used for bushing insertion and bushing removal purposes is the manner in which the bushing contacting mandrel is employed. The same tool parts are utilized for each of the aforesaid purposes, and, by and large, those parts are employed in substantially the same way in each case. This is true, in a sense, of even the bushing contacting mandrel, since that part serves, in each instance, as a member which bears against a bushing, in the one case to push it into its bearing seat and in the other to remove it therefrom, at one end and against a locking fork at the other end, the fork being so engaged with the puller rod to serve as a barrier for the prevention of mandrel migration from its proper position on the rod. Because, however, of the direction of movement of the bushing and mandrel, the mating of these two parts serves well for bushing insertion purposes whereas it produces unsatisfactory contact for bushing removal purposes, unless another mandrel is used conjunctively with the aforesaid one in a manner obvious to those skilled in the art from the present teachings.
Mandrel 19 is oriented on rod 17 for bushing removal applicability of the pictured embodiment of my tool with its flanged end abutting a face of the bushing to be removed, this orientation being illustrated by FIGURE 3 which shows a separate mandrel so abutting each of old bushings 13 and 15. With the mandrel thus oriented and positioned, a locking fork 21 is stationed adjacent its nonfianged end, as illustrated in FIGURE 3, and the tool is then put to use, as previously indicated, by tightening nut 27 on the threaded end of rod 17. Continued tightening of the nut causes the rod-fork-mandrel configuration to ride to the right, as seen in FIGURE 3, thereby forcing the mandrel-adjacent bushing out of its bearing seat. FIGURE 3 illustrates separate phases of this operation by showing old bushing 15 in the process of being extracted and old bushing 13 after complete removal from its seat in bearing 3b. After tool 1 has completely served its bushing removal purpose, it can be disassembled and removed from the crankcase in substantially the same way this is accomplished after bushing insertion use.
The new tool of this invention readily lends itself to puller rod manipulation from either end of an engine crankcase. This is important since one end of a crankcase must sometimes be favored over the other for a particular purpose such as, for example, the insertion or removal of a bushing from an end bearing. Still another instance of the tools versatility is an adaptability for combinational bushing removal and insertion use of simultaneous, or other,
nature. My new tool is not limited in applicability to the servicing of cam bearings in internal combustion engines, and it can be employed for any purpose, and in any en vironment, to which its structural character and use capability lend themselves.
Attention is directed to the fact that FIGURE 6 is not a view of a mandrel and bushing positioned and oriented consistently with the FIGURE 5 showing of those parts, although it is purportedly taken along a section line through the latter figure. In this connection, FIGURE 5 shows the mandrel and bushing in bushing removal relationship while FIGURE 6 depicts them in the mated relationship suggestive of bushing insertion tool use. While such transpositioning of parts between section-line-related views is somewhat unusual in patent drawings, it was here intentionally done in order to best illustrate certain partsinterfitting relationships of a now obvious character. No confusion is anticipated as a result of my use of this illustrative technique, particularly in view of the present explanation, and hence it is felt to be entirely proper under the circumstances.
Attention is now directed to FIGURES 7 through 10, which show an alternatively-formed mandrel suitable for use as a part of my tool in lieu of the more conventional mandrel 19 heretofore described and exemplified in FIG- URES 1 through 6. The new mandrel is shown generally at, and hereinafter referred to as mandrel, M. Its chief characteristic is a controllable capacity for expansion, as a result of which it can .be hand-adjusted to fit, or work cooperatively with, bushings throughout a relatively wide range of sizes. The beneficial advantages of such size adjustability will be readily apparent to those skilled in the art, perhaps the most obvious being its elimination of, or, at least, mitigation against, any critical necessity for an assortment of mandrel sizes to suit the tool of its incorporation for use in a variety of bushing size situations.
Mandrel M, unlike mandrel 19, which is of one-piece construction, is made up of a plurality of parts, so sized, shaped and fitted together as to form a mandrel-like rider unit slidably engageable with puller rod 17. Mandrel M, in fully assembled form, has a cylindrical body portion 39, with a fiange configuration 39 at one end, which serves a mandrel function; a sleeve 31, having a radial flange 31a at one end and a threaded portion 31b at the other, passing concentrically through said body portion; two cones 35 and 37 concentrically fitted on sleeve 31 in loosely slidable relationship, one at each end of said body portion with its conical face inserted in a mating hollow, later to be described, therein; a round hand nut threadedly engaged with threaded portion 31b of sleeve 31; and two resilient O-rings 41 and 43, made of neoprene or an equivalent material, encircling said body portion in planes perpendicular to its axis and confined in two receptive grooves 39a and 39b therefor in its cylindrical outer wall.
As FIGURES 7, 8 and 9 show, body portion 39 is made up of four equally sized segments 39c, each, because of its structural similarity to the others, being identified by the same reference numeral. The four segments 390 are parallel to the axis of the mandrel and when viewed in cross section, as in FIGURE 9, they are seen to represent the four quadrants of its body portion 39. The segments are arcuately hollowed at their radially inner boundaries to fit together in surounding relationship to sleeve 31 and, as previously indicated, permit a loosely sliding relationship between the sleeve and mandrel body portion which they comprise.
The two ends of body portion 39 are conically hollowed, as shown at 39d and 392, to angular dimensions corresponding to those of the conical faces of cones 35 and 37, previously referred to and shown at 35a and 37a, respectively. The angles of cone slope of the two cones are equal, each being about 45 degrees. The invention is not limited to a 45-degree cone face angle, however, and any other conducive to tool performance in the manner taught herein will suffice for my purpose. As will soon be seen, mandrel M is caused to expand and achieve the size adjustability advantage previously referred to by the application of pressure to the ends of its body portion through the two cones 35 and 37, respectively. The pressure is so applied as to cause equal radial expansion of the ends of body portion 39 and thus maintain its outer cylindrical walls in axially parallel orientation.
The structure and manner of operation of mandrel M will, it is believed, be clear from what has already been said, particularly when considered in conjunction with the drawings in their totality. Briefly, mandrel M is put to use by first making sure it is assembled in the manner and order of arrangement of parts illustrated in FIGURES 7, 8 and 10. The mandrel can be otherwise assembled, but the preferred arrangement is as indicated, with particular care being taken to see that the flanged end of body portion 39 is adjacent the cone abutting the flange of sleeve 31. The reason for this is to avoid the application of pressure to the nonflanged end of the mandrel during subsequent bushing insertion use of the tool. No necessity is seen for going into this aspect of tool use in any greater detail, since the involved particulars will be clear to those skilled in the art, especially in view of the wealth of detail relative to the manner of functioning and principles of operation of my tool heretofore given. In this connection, however, it should perhaps be noted that mandrel M lends itself primarily to bushing insertion utility, where pressure is normally brought to bear on the flanged end only of a mandrel, rather than bushing removal appli cation where pressure of some sort will often be applied at its nonfianged end. The use of the mandrel is not rigidly limited in this fashion, however, and it may be otherwise employed, if desired, within the scope of my invention.
Returning now to consideration of the use of mandrel M, the preferred way in which its various parts are assembled is, as indicated, the same as illustrated in FIG- URES 7, 8 and 10. The two cones, 35 and 37, easily slip onto sleeve 31 in loosely sliding relationship and hand nut 33 is readily screwed in place on the threaded end of the sleeve, as shown particularly well in FIG- URE 10. The resilient O-rings, properly sized for the purpose, are easily slipped into place in mandrel grooves 39a and 39b. These O-rings serve to retain the mandrel body portion segments 390 in place while at the same time permitting them to expand radially outwardly under properly directed forces. Such forces are applied by tightening hand nut 33 against cone 35. The conical faces of contactibetween cones 35 and 37 and their respectively mating hollows in the ends of body portion 39 of the mandrel are machined to low friction smoothness, thus permitting the cones to slide easily into said hollows under the application of relatively slight pressure. Also, the abutting contact surfaces of hand nut 33 and cone 35 are machined to low friction smoothness, to permit relatively effortless turning of the nut during preparation of the tool for use.
For the foregoing reasons, it is a relatively easy and simple matter to tighten hand nut 33 to the maximum limit of the radial expansion of body portion 39 resulting therefrom, the magnitude of said limit being determined by various design factors known to those skilled in the art. It will be appreciated that the presence of equally angled cones 35 and .37 (which are, as illustrated, of slightly differing, but could just as effectively be equal, axial dimension) in the mandrel M assembly results in the creation of a force pattern, upon tightening of the hand nut 33, on body portion 39 of such character as to cause equal end expansion thereof, and hence preserve its mandrel-like form, throughout the whole range of its expandability. It will also be appreciated that the cones hold body portion segments 390 in end captivation against axial movement relative to each other to further preserve the mandrel-like form of the body portion during its expansion as a result of the hand nut tightening adjustment.
After its assembly, a mandrel M is employed, as a part of my tool, in much the same fashion, for cam bushing insertion purposes, as is a mandrel 19. Likewise, installation of the tool in an engine crankcase is substantially the same where a mandrel M is employed as it is in the case of mandrel 19 employment, except that with the Mandrel M one additional step is required to station it for bushing insertion use. Thus, the assembled mandrel is first placed in proper working position on rod 17 in the same way a mandrel 19 would be jockeyed into place thereon, except that the former is so positioned by threading the rod through its central sleeve member 31 whereas in the case of the latter (mandrel 19) the rod is passed directly through a mating opening in its body. Sleeve member 31 is, as previously indicated, sized to fit loosely on rod 17, thus permitting the mandrel assembly to ride back and forth thereon. The mandrel M is next inserted to full mating engagement with a properly sized, and located bushing, the thus-mated parts having been so previously positioned and oriented on the rod, and now being so engaged, as to correspond in all signif icant particulars to the mandrel-bushing positional set-up exemplified by new bushing 9 and its mated mandrel on FIGURE 2.
For obvious reasons, the mandrel M is preferably maintained in its unexpanded, or retracted, condition until it has "been mated with a bushing in the just-described manner. After the mating, however, the mandrel is enlarged to a condition of snug fitting, but not binding, contact with the bushing, this being accomplished by tightening the hand nut 33 the necessary amount for that purpose. This tightening of the nut 33 is the additional step of the mandrel M stationing procedure referred to above.
After the mandrel M has been properly mated, as described, with a bushing to be seated in a crankcase bearing, the tool of which it forms a part is readied for use by the placement of a locking fork 21 in prong-slot engagement with its (the tools) rod 17 adjacent the flanged end of sleeve 31 of the mandrel, the fork placement being made with the rod in proper position (as determined by reference to previously included mandrel 19 positioning instructions) for bushing insertion applicability. The tool is now ready to be put to use, this being accomplished by a tightening nut 27 on rod 17 which causes the rod to advance the mandrel and its mounted bushing adjacent the aforesaid locking fork in the proper direction for engagement of the latter (bushing) with its destination bearing. The tightening of the nut is, of course, continued until the bushing is fully seated in the bearing.
After the bushing has been seated, it is a simple matter to loosen nut 27, back off the puller bar, remove the locking fork and disengage the mandrel M from the seated bushingto permit immediate reuse, or disassemble, of the tool. The disengagement of the mandrel from the bushing is easier than that of a mandrel 19 under similar circumstances. This is true because the body portion of a mandrel M can be readily contacted by hand manipulation of its cooperating nut 33 to permit its easy withdrawal from the bushing with substantially no possibility of sticking, whereas the mandrel 19, lacking such shrinking capacity, is vulnerable to sticking so badly within a seated bushing as to make separation of the two parts difficult.
The use of a hand nut for the size adjustment of the mandrel M, in addition to contributing to ease and simplicity of operation, avoids the danger of too tight mandrel-bushing adjustment which would, of course, be present were it necessary to employ a nut requiring a wrench for that purpose. The parts of the mandrel M, other than the O-rings, are of metallic construction, the selection of suitable metals or alloys for which is a 13 matter of no difficulty to those skilled in the toolmaking or related arts. In this connection, I believe a mild steel, such as, for example, a steel having a Rockwell hardness of about 35, to be a particularly suitable material of construction for the segments 390 of the expandable body portion of the mandrel.
The above-described version of my expandable mandrel, as is true of the other illustrated parts of my tool, herein illustrated for. exemplary purposes only. Thus, any unit capable of serving as the equivalent of that mandrel for purposes of this invention can be employed as a functional part of my new tool, if desired, and the same thing is true relative to its component parts. It is therefore apparent that my expandable mandrel can exist in many variant forms, all capable of use as taught herein and hence within the compass of my invention. Some of the more obvious of these variant forms include a mandrel similar to mandrel M but with other than two O-rings substituted for O-rings 41 and 43; such a mandrel with annular spiral springs substituted for said O-rings; an expandible mandrel with other than four body portion segments; etc.
Where annular sprial springs are used in lieu of the rubber or plastic O-rings of mandrel M, care should preferably be taken to see that they are of sufficiently small cross sectional diameter to avoid contact with inner bushing surfaces during use of the tool, or that a protective body covering for the mandrel be employed to shield the bushing surfaces from possibly damaging contact therewith. For reasons made obvious by these comments, resilient O-rings are preferred over their spiral spring counterparts for the indicated purpose, although alternative use of the latter clearly falls within the scope of my invention.
It will be apparent from the foregoing discussion of the many possible forms of the expandible mandrel unit of my tool, that the tool as a whole can exist in an infinitely great number of embodiments variant to that specifically illustrated yet within the scope of the present invention. Many of these embodiments have been discussed or mentioned hereinabove and countless others will suggest themselves to those skilled in the mechanical arts from the present teachings. Exemplary of the latter would be a tool similar to that illustrated but with equivalent means substituted for one or both of its thrust disc 23 and thrust bearing 25 elements; such a tool with nonfianged mandrels (for end support use, conjunctive use with flanged mandrels, or other functional purpose or purposes), in addition to flanged ones, as component parts; such a tool with straight-handled forks as component parts; etc.
The various elements of my tool can be of any size so long as they are capable of performance in accordance with the objects of this invention. Preferred or optimum sizes are matters of easy selection by those skilled in the art, using the present disclosure as a guide. However, to give a feel for the tool size presently felt to be most commonly suitable for internal combustion engine use, certain design particulars of a tool which I have constructed and used with much success, and which, I believe, satisfies this criterion, are set forth below. These particulars are tabulated under two headings, a part (or feature) heading and a size heading. For simplicitys sake, those items under the part (or feature) heading will be designated by the reference characters of their drawing-illustrated Prototypes.
Part (or feature): Size Puller rod 17 OD. x 33 /2" long. Threaded part 17a of the puller rod 5" of N.C. thread.
Slots 17b on puller rod Oppositely parallel, 1" (axial length between pairs), 7 deep, A wide.
14 Nut 27 N.C. Thrust bearing 25 T 76 Timken.
The above list is not complete as to all parts and features of the tool, but is believed sufiiciently adequate for the purpose as stated.
My invention has been described in considerable detail in order to comply with the legal requirement for a full public disclosure of its preferred embodiment. However, as I have already made clear, there are many embodiments of the invention not specifically disclosed which can be prepared and used in accordance with present teachings. It is emphasized, in final summary, that all such embodiments which maintain a structural character and functioning capability consistent with the integrity of my invention as taught herein fall within its scope so long as they are encompassed by the following claims.
1. A tool particularly useful for the insertion of bushings in, and the removal of bushings from, internal combustion engine cam shaft bearings comprising a puller rod adapted to extend freely through aligned bearing openings in an engine crankcase; generally cylindricallyshaped mandrel means adapted to fit slidingly on said rod and urge a bushing into or out of a bearing opening in said crankcase when maintained in properly biasing contact therewith during use of the tool; locking means for preventing movement of the mandrel means relative to the rod during movement of the latter while the tool is in use; means for preventing rotation of the rod during such movement; and pulling means for steadily urging the rod in a direction coaxial with said bearing openings when the tool is in use with the mandrel means locked against movement relative to the rod in biasing contact with a bushing and the rod locked against rotational movement, whereby the bushing is urged into or out of one of said bearing openings; said mandrel means comprising:
(a) a radially flanged sleeve threaded for at least a portion of its length from one end and adapted to slidably engage said puller rod;
(b) a. body portion consisting of radially segmented elements adapted to fit matingly around said sleeve and form a concentric mandrel-like body enclosing it for a part of its length, said mandrel-like body being radially flanged, conically depressed at both ends and grooved around its nonfianged portion; and
(c) two cone members with concentric hollows sized to admit said sleeve in loosely sliding relationship, each having a conical face shaped to fit into a conically depressed end of the body portion of said mandrel means.
2. Tool means particularly useful for the insertion of bushings in internal combustion engine cam shaft bearings and the removal of such bushings therefrom, comprising:
(a) at least one puller rod of round cross section adapted to extend freely through aligned bearing openings in an internal combustion engine crankcase when the tool means is in use said puller rod eing threaded to receive a nut from at least one end for a portion of its length and having at least one hollow matingly receptive to a male part;
(b) at least one mandrel means of generally cylindrical shape adapted to slidingly fit on said puller rod and capable of radial size adjustability whereby it can be readily expanded and contracted to fit a plurality of differently sized bushings for tool means use purposes, comprising:
(1) a radially flanged sleeve threaded for at least a portion of its length from one end and adapted to slidably engage said puller rod;
(2) a body portion consisting of radially segmented elements adapted to fit matingly around 15 said sleeve and form a concentric mandrel-like body enclosing it for a part of its length, said mandrel-like body being radially flanged, conically depressed at both ends and grooved around when it is disposed in bearing penetrating tool use orientation and said male part of the locking means is mated with said hollow therein. v
16 (1) a sleeve having a radial flange at one end, threaded for at least a portion of its length from the other end and adapted to slidably engage said puller rod;
its nonflanged portion; and (2) an elongated body portion consisting of a (3) two cone members with concentric hollows plurality of longitudinally segmented elements sized to admit said sleeve in loosely sliding of equal size adapted to fit matingly around said relationship, each having a conical face shaped sleeve and form a concentric mandrel-like body to fit into a conically depressed end of the body enclosing it for a part of its length, said manportion of said mandrel means; and drel-like body being radially flanged at one (0) locking means having a male part adapted to fit end, conically depressed at both ends and havmatingly into the aforesaid hollow in said puller ing a plurality of circumferential grooves rod and a handle portion adapted to contact a blockrunning around its nonfianged portion in a ing obstruction at some point on its orbital path plane perpendicular to its axis;
around said puller rod upon rotation of the rod (3) two cone members with concentric hollows sized to admit said sleeve in loosely sliding relationship and each having a flat face and a conical face shaped to matingly interfit with a 3. Tool means particularly useful for the insertion of bushings in internal combustion engine cam shaft bearings and the removal of such bushings therefrom, comprising:
(a) at least one puller rod of round cross section adapted to extend freely through aligned bearing openings in an engine crankcase when the tool means is in use, said puller rod being threaded from at least one end for a portion of its length and having a plurality of pairs of slots spaced along its length;
(b) nut means adapted to threadedly engage a threaded end portion of said puller rod;
(c) thrust means adapted to encircle said puller rod,
conically depressed end of the elongated body portion of said mandrel means; (4) a hand nut matingly engageable with the threaded portion of said sleeve; and (5) a plurality of resilient O-rings corresponding in number to the number of said circumferential grooves in and around the elongated body portion of said mandrel means; and (e) at least one locking fork having an end with two prongs adapted to fit simultaneously into a pair of said slots spaced along said puller rod and a handle adapted to contact an internal wall of an engine crankcase at some point on its orbital path around bear against the outer surface of a crankcase wall surrounding an opening therein and provide a surface of thrust against which said nut means can said puller rod, upon rotation of the latter, when said locking fork has its prongs inserted in a pair of said slots in said puller rod and the puller rod turn on a threaded end portion of said puller rod when the latter passes through said opening for cam shaft bearing servicing purposes in accordance with this invention;
(d) at least one mandrel means of generally cylindrical shape adapted to slidingly fit on said puller rod and 2,317,405 capable of radial size adjustability whereby it can 2,596,549 be readily expanded and contracted to fit a plurality of differently sized bushings for tool means use purposes, comprising:
is disposed in operating position within said crankcase.
References Cited UNITED STATES PATENTS 4/1943 Rutten 29263 5/1952 Hamilton 29263 WILLIAM FELDMAN, Primary Examiner.
MYRON C. KRUSE, Examiner.