US 3062695 A
Description (OCR text may contain errors)
Nov. 6, 1962 I w. E. HULL 3,062,695
METHODS OF AND MEANS FOR SECURING TOGETHER THERMOPLASTIC MEMBERS Filed June 30, 1959 4 Sheets-Sheet 1 f 3 =(Z6 il 3 45 2 t ::24 I
I 22 if I I [k I I Id I ah M -I 30 3| I I 2 I 4-3 39 4X 40 i x BYM/WM- W. E. HULL Nov. 6, 1962 METHODS OF AND MEANS FOR SECURING TOGETHER THERMOPLASTIC MEMBERS Filed June 30, 1959 4 Sheets-Sheet 2 INVENTOR. Mu TR E. flu BY Afl-axmzy Nov. 6, 1962 w, HULL 3,062,695
METHODS OF AND MEANS FOR SECURING TOGETHER THERMOPLASTIC MEMBERS Filed June 50, 1959 1 4 Sheets-Sheet 3 INVENTOR. Nam/e E. Ill/LL W. E. HULL Nov. 6, 1962 METHODS OF AND MEANS FOR SECURING TOGETHER THERMOPLASTIC MEMBERS 4 Sheets-Sheet 4 Filed June 50, 1959 INVENTOR. Mu Tt'R E. f/l/LL A #anwsr rates The present invention relates to a novel mechanical movement and to methods of and means for securing together thermoplastic members, and the principal object of the invention is to provide new and improved methods and apparatus of such character.
It has long been recognized that members formed of certain kinds of material may be secured together by rubbing one member upon the other until their abutting surfaces soften under frictional heat and then holding the members forceably together until such surfaces cool and harden. This causes the members to so firmly adhere together that an integral structure is obtained.
Heretofore, this member movement has been obtained by spinning one of the members about an axis relative to the other and then stopping the spinning movement when the abutting member surfaces have sufficiently softened. While this arrangement has been satisfactory for securing certain types of members together, it has been limited to situations where it is immaterial at which portion of its cycle of rotation the movable member is stopped for fusion with the stationary member. When, however, a pair of members must be so secured together that they will bear a predetermined relationship with each other as respects the axis of rotation of the movable member, certain problems arise.
One of the problems which arises when relative member movement is effectuated by spinning one of the members is the difficulty of stopping the spinning member at precisely the proper portion of its cycle to insure the desired member relationship when the softened member surfaces cool and harden. Another problem presented by spinning arises because all portions of the surfaces being rubbed together did not move relative to each other at the same speed. This is a result of the fact'that those surface portions close to the axis of rotation move at a relatively low linear speed While those radially outwardly from the axis of rotation move at a relatively higher linear speed. Accordingly, under some circumstances, there may occur the undesirable result that some surface portions to be joined reach a state of fusion prior to other surface portions to be joined.
The present invention provides a novel method of and means for bonding respective surfaces of thermoplastic member together without the disadvantages aforesaid of the prior art expedient of spinning one of the members against the other and further provides a novel mechanical movement incorporated in the apparatus which practices the novel method. Other advantages will become apparent from a study of the following description and from the drawings appended hereto.
In the drawings accompanying this specification here is shown, for purpose of illustration, embodiments which the invention may assume, and in these drawings:
' FIGURE 1 is a fragmentary front elevational view of apparatus illustrating an embodiment of the present invention,
FIGURE 2 is a top plan view of the apparatus seen in FIGURE 1,
FIGURE 3 is an enlarged fragmentary sectional view generally corresponding to the line 33 of FIGURE 2,
FIGURE 4 is a fragmentary sectional view generally corresponding to the line 4-4 of FIGURE 3 and with certain parts shown in other positions by means of phantom lines,
FIGURE 5 is a view similar to FIGURE 3 but with means Patented Nov. 6, 1962 the parts in another position in full lines and in still another position in phantom lines,
FIGURE 6 is an enlarged, fragmentary sectional view generally corresponding to the line 66 of FIGURE 2,
FIGURE 7 is a view similar to FIGURE 6 but with certain parts in another position,
FIGURE 8 is a sectional view generally corresponding to the line 8-8 of FIGURE 7,
FIGURE 9 is a view similar to FIGURE 8 but with certain parts in another position in full lines and in still other positions in phantom lines,
FIGURE 10 is a fragmentary sectional view of another embodiment of the invention,
FIGURE 11 is an exploded perspective view of certain parts seen in FIGURE 10, and
FIGURE 12 is a perspective view of a pair of members, shown in separated relation, which the present invention contemplates joining together.
As previously mentioned, the present invention contemplates the joining together of two thermoplastic members M-1 and M-2, such as those illustrated in FIGURE 12, to form a unitary structure. Briefly, and with reference to FIGURE 12, each member is a generally hollow, semispheriod and each has surfaces S which are adapted to be fused together to form a unitary, generally spherical hollow body which will ultimately form a part of a magnetic compass. Although it forms no part of the present invention, it is to be understood that the two hollow members M4 and M-2 will be assembled with certain parts encased therein. The interior of the hollow body thus formed will later be filled with a liquid introduced through a small aperture in one of the members. Upon closing of the aperture, there will be provided a hermetically sealed, liquid filled hollow body.
It is important to note that one of the members is provided with opposed flats F which must register with similar flats on the other member when the members are secured together. Accordingly, it will be clear that the members must be secured together precisely in alignment if respective fiats F are to be in register. It is, therefore, an object of the present invention to provide methods of and means for securing the thermoplastic members seen in FIGURE 12 together in properly aligned relation.
An embodiment of apparatus for securing together the members M1 and M-2 seen in FIGURE 12 is illustrated in FIGURES 1 through 9. As best seen in FIG- URE l, the apparatus of the present embodiment may conveniently be divided into two main portions. Firstly, there is what will hereinafter be referred to as the clamping portion Ill of the apparatus and secondly, what will be referred to as the drive portion 11 thereof. In the present embodiment, both apparatus portions are adapted to be supported by the work table 12 of a conventional drill press 13 whose vertically disposed, rotatable spindle (not shown) is connected to the apparatus drive portion 11 in a manner and for a purpose later to be disclosed.
Still referring to FIGURE 1 but as also may be seen in FIGURES 3 and 4, the clamping portion III of the apparatus comprises a base plate 14 and a top plate 15 secured together in vertically spaced-apart relation by means of transversely spaced, generally vertical tie rods It; which are pinned or otherwise secured to respective plates 14, 15. Interposed between the plates aforesaid and slidable along the tie rods 16 for a purpose to be disclosed is an intermediate plate 17.
Secured to or as herein shown formed as an integral part of top plate 15 is an upwardly extending sleeve 18 forming an elongated vertical bearing for a hollow spindle l9. Spindle 19 has a radially enlarged lower portion 29 forming a housing which projects downwardly from top plate ISand which has a downwardly facing recess 21. Interposed between plate 15- and portion 20 of spindle 19 speaeos is a ball thrust bearing assembly 22. Threaded upon the upper end of sleeve 19 is a nut 23 which retains the spindle assembled with the top plate and a jam nut 124 prevents unintentional shifting of nut 23. For a purpose to be disclosed, an ejector rod 24 having an enlarged lower end portion is slidable within hollow spindle 19 and projects upwardly therebeyond. A suitable spring 25 may be fitted over rod 24 and have its lower end seated against spindle 19 and its upper end engaged with a pin 26 carried by and extending transversely of the rod to resiliently urge the latter to the position seen in FIGURE 3.
Turning now to plate 17, a housing 27 similar to housing portion 20 of spindle 19, is bolted or otherwise affixed to plate 17 to project upwardly therefrom in vertical alignment with the spindle portion 29, or housing, aforesaid. Housing 27 is similar to housing 20 in that it also has a recess 28 which, however, faces upwardly rather than downwardly as does housing recess 21. Also for a purpose to be disclosed, an ejector rod 29 having an enlarged upper end portion is slidable within an aperture in the bottom of housing 27 and is normally urged by gravity to the position seen in FIGURE 3.
As appears in FIGURE 3, one of the members to be joined, for example, member M-1 is adapted to be seated within and accurately located by housing 27. Obviously, such members are so carried by respective housings that their surfaces S to be joined are in abutting relation and the members are so oriented with each other that they are aligned as required.
Any suitable expedient may be employed to form in respective housings a pocket 36 for closely receiving respective members. At the present time, each pocket 30 is formed by pouring a quantity of fiowable material 31 in each housing recess and then embedding in such material, while still flowable, one of the members to be joined. When the material hardens, the member may be removed thus leaving a perfectly formed impression in the hardened material for closely receiving members identical to the one from which the impression was made.
Means are provided for reciprocating the intermediate plate 17 from the position seen in FIGURES 1, 3 and 4 to the position seen in FIGURE 5 and at the present time, the following construction is employed. Still referring to FIGURE 3, a hollow sleeve 32 depends from plate 17. Such sleeve, of course, need not be formed integrally with plate 17 but may be aiiixed thereto by any suitable means. Slidable within sleeve 32 is a tube 33 which is transversely apertured to pass a pin 34. Sleeve 32 is also transversely apertured to pass pin 34; however, such aperture is vertically elongated to provide a slot shown at 35 for a purpose to appear. The lower end of tube 33 projects downwardly from sleeve 32 and is threaded to receive a nut 36. A coil spring 37 is interposed between the nut and the lower end of sleeve 32 to resiliently urge the transverse pin 34 carried by tube 33 toward the bottom of slot 35.
A toggle linkage is employed to efiect vertical reciprocation of pin 34 and consequent vertical reciprocation of plate 17 and as best seen in FIGURES 3 and 4, a pair of toggle links 38 have their upper ends secured to respective ends of pin 34 and their lower ends pivoted to an end of respective links of a second pair of toggle links 39. The opposite ends of the second pair of toggle links are pivoted to the base plate 14 by means of brackets 40 sup porting a pivot shaft 41. A lever 42 is attached to pivot shaft 41 for effecting rotation thereof and consequent movement of the toggle links between the full line position seen in FIGURE 4 and the phantom line position. Lever 42 may be actuated by either a hand or foot control or by means of, for example, a fluid cylinder if power actuation is desired.
Slidable within tube 33 is a rod 43 whose lower end rests upon pivot shaft 41. As will later appear, the upper end of rod 43, while spaced from the lower end of ejector rod 29 in the position of parts seen in FIGURE 3, is adapted to pass through a transverse aperture 44 in pin 34 to engage ejector rod 29 when plate 17 is lowered. Means are also provided for engaging the upper end of ejector rod 24 upon lowering of plate 17, such means presently comprising a rod which is secured to plate 17 and which passes through an enlarged aperture in plate 15 and which has a transversely extending upper portion for engagement with the ejector rod 24.
Turning now to the drive portion 11 of the apparatus and with particular reference to FIGURES l, 6 and 7, such portion comprises a housing 46 secured to top plate 15 of the apparatus clamping portion 19 by means of capscrews 47. Such housing is presently formed of respective upper and lower portions 48 and having respective complementarily formed flange portions 56 and 51 secured together by capscrcws 52. For a purpose to appear, flange portions 50, 51 provide an annular space 53 defined by opposed, surfaces provided by upper and lower Washer-like members 54, 55 of suitable bearing material.
Rotatably carried by housing 46 and projecting upwardly therefrom is a crankshaft 56 whose crank arm 57 is disposed within the housing. Crankshaft 56 is adapted to be rotated by the spindle (not shown) of the drill press 13 and is also movable vertically with such spindle from the position seen in FIGURE 6 to the position seen in FIGURE 7.
Anchored to crank arm 57 so as to form an integral part thereof is an elongated pin 58 which extends transversely of the crankshaft axis but preferably at an angle of less than ninety degrees therewith. At the present time, the axis of pin 58 intersects the axis of the crankshaft; however, such axes could as well be non-intersecting. Slidable axially of pin 58 is a collar 59 which is keyed to the pin to insure against relative rotation therebetween, a nut 60 being located at the free end of the pin to retain the collar assembled therewith.
Collar 59 has an annular, peripheral groove 61 formed therein which is concentric with the axis of rotation of the crankshaft 56 when the collar is positioned as seen in FIGURE 6. It is to be understood, however, that upon downward movement of crankshaft 56 from the position seen in FIGURE 6 to the position seen in FIGURE 7, pin 58 will slide downwardly through the collar. Now then, because of the inclination of pin 58 with the axis of the crankshaft, the collar will be shifted transversely of the crankshaft axis so that its groove 61 will now be cccentric therewith as seen in FIGURE 7.
Rotatably seated in groove 61 of collar 59 is a connecting rod member 62 which closely fits between the upper and lower confines of the annular space 53. The inten mediate portion of connecting rod 62 projects outwardly of housing 46 through an aperture 63 therein and its free end terminates in a loop 64 which is pivotally engaged with the free end of an arm 65 (see especially FIGURES 8 and 9). The opposite end of arm 65 is tightly clamped about the enlarged lower portion 20 of spindle 19 for unitary movement therewith. Completing the apparatus drive portion 11 is a bowl 66 which underlies the housing 46 and forms a receptacle for lubricating oil. An aperture 67 in the bottom of housing portion 49 provides for free flow of oil from the interior of the bowl to the interior of the housing.
Assuming that the parts are positioned as seen in FIG- URES 3, 4 and 6 with a member M-l seated in pocket 39 of the spindle housing 20, with a member l /I2 seated in the pocket of the housing 27, and with the drill press spindle (not shown) rotating crankshaft 56, it is to be understood that connecting rod 62 will be stationary, despite rotation of the crankshaft, since annular groove 61 of collar 59 is at this time running concentric with the rotational axis of the crankshaft. Accordingly, with connecting rod 62 stationary, spindle 19 and its housing 20 will be held stationary, with the members to be joined, M-1 and M2, in the desired alignment.
While the members M-1 and M2 are at this time being held with their surfaces to be joined in abutting relation, it is to be noted in FIGURE 4 that the toggle links 38, 39 are not yet aligned. If lever 42 is now rotated clockwise sufficiently to align the toggle links, pin 34 will move upwardly in its slot 35, since plate 17 cannot move up further because the members M-1, M-Z are in abutting relation, to further compress the spring 37. It is to be understood that the pressure thus exerted forcing the members M-l, in M-2 together is dependent upon the degree of compression of the spring 37, which compression may readily be regulated by adjoining nut 36 along the threaded lower portion of tube 313.
If the crankshaft 56 is now moved downwardly from the position seen in FIGURE 6 toward the position seen in FIGURE 7, it will be understood that collar 59 will be shifted radially of the crankshaft so that its annular groove 61 runs eccentrically thereof. This eccentric movement of the collar groove will cause a corresponding eccentric movement of the connecting rod 62 which will in turn cause reciprocation of the spindle 19 about its axis. Clearly, the further down the crankshaft 56 is moved, the greater will be the eccentricity of the collar groove, and the greater will be the distance through which the spindle and therefore the member M-l is reciprocated.
It will be clear that with member M2 being held st tionary and with member M1 being reciprocated as aforesaid, frictional heat will be developed between the abutting member surfaces. When sufiicient heat has been developed to cause fusion of the abutting member surfaces (a matter of but a few seconds being required), crankshaft 56 will be returned to the position seen in FIGURE 6 to thus center the collar groove 61. This will once again immobilize the crankshaft to hold the respective members M-1, M-2 in the proper aligned relation while the heretofore softened, abutting member surfaces cool and harden.
As previously mentioned, spring 37 is compressed when the members M1, M-2 are forced together; accordingly, as the abutting member surfaces soften, the spring 37 will maintain pressure upon the members by moving plate 37 further up, if necessary, to follow up the softened member surfaces and thus prevent the loss of pressure which would otherwise occur.
Upon cooling of the softened member surfaces (this also requiring but a few seconds) the toggle links will be shifted to the phantom-line position seen in FIGURE 4. This will lower the plate 17 to the position seen in FIG- URE 5 to thus separate housings 27, 20 to permit removal of the fused together members M1, M-2. As plate 17 is lowered, the transversely extending portion of rod 45 will engage the upper end of ejector rod 24 to effect downward movement thereof against the urging of spring 25 to thus eject the member M-It from its pocket. Additionally, upon such lowering of plate 17, the lower end of ejector rod 29 will engage the upper end of rod 43 whereupon further downward movement of the ejector rod 2? with the plate 17 will be arrested. Continued downward movement of the plate will cause ejector rod 29 to eject the member M-Z from its pocket. With both of the members M-1, M2 ejected from respective pockets, such members, which are now fused together as before described, may readily be removed and replaced with two more members which are to be joined.
To join together another pair of members M-1, M2, plate 17 will first be elevated to the phantom line position seen in FIGURE 5 wherein the ejector rods 24, 29 are withdrawn within respective member pockets. Each member will then be inserted within its respective pocket and the plate 17 further elevated to its uppermost position as seen in FIGURE 3. The previously described operations will then be repeated to join the members together.
As hereinabove disclosed and assuming crankshaft 56 to be rotating, when the latter is in the elevated position seen in FIGURE 6 the connecting rod 62 will be immobilized because of the concentricity of collar 59 with the crankshaft axis to thus hold member M-l in fixed, predetermined relation with member M2. When, however, the crankshaft is shifted to its lowermost position seen in FIGURE 7, collar 59 will be in its position of maximum eccentricity to thus cause maximum crankshaft throw and maximum movement of member M-l relative to member M-2. Obviously, with the crankshaft positioned intermediate the positions seen in FIGURES 6 and 7, the throw of the crankshaft and therefore the relative movement of the members will be proportionately less.
From the foregoing, it is to be understood that an important feature of the invention is that as the rotating crankshaft is shifted from the position seen in FIGURE 7 to the position seen in FIGURE 6, the path of travel of member M-ll progressively decreases from maximum to Zero and with the members in the desired predetermined relation when the path of travel aforesaid is thus reduced to Zero.
The embodiment of the invention seen in FIGURES 10 and ll is similar to that heretofore disclosed; accordingly, similar parts are identified with the same reference characters as before but with the suflix a added. operationally speaking and as will appear, the principal difference between the construction heretofore described and that about to be disclosed is that a different relative movement is imparted to the members to be joined.
As illustrated in FIGURE 10, the clamping portion of the apparatus is combined in a single unit with the apparatus drive portion. In this construction there is provided a fixedly positioned, top plate 15a and a vertically movable plate 17a. Considering first plate 170:, the latter carries a housing 27a which may be identical to housing 27. Additionally, linkage identical to that previously described may be employed for effecting vertical reciprocation of plate 17a.
Turning now to plate 15a, the latter fixedly carries a member 68 having a sleeve portion 69, a radially enlarged, inverted cup-shaped portion 70 and a further radially enlarged flange portion 71. Rotatable within sleeve portion 69 of member 68 is a shaft 72 having a radially enlarged flange portion 73 disposed within portion 70 of member 68. Shaft 72 is adapted to be rotated by the drill press arbor (not shown) and is vertically movable therewith, during its rotation, for a purpose to appear.
Anchored in shaft portion 73 to depend therefrom are a plurality of pins 74 herein shown to be two in number. It is to be understood that such pins are preferably spaced equally about the shaft axis and that while only two in opposed relation are herein shown, three, four or even more could, if desired, be employed. In any event, pins 74 are in parallel relation and are inclined with respect to the axis of shaft 72. Slidab-le on pins 74 in a washerlike member 75 having a central aperture 76 which, in the position of parts seen in FIGURE 10, is concentric with the axis of shaft 72.
Secured to the underside of flange 71 of member 68 by means of capscrews '77 is annular member 78 having an annular, radially inwardly extending flange portion 79 which is spaced from the aforesaid flange 71. Slidably resting upon the upper face of flange 79 is a housing 89 which corresponds to the housing 24 of the previously disclosed embodiment. Housing 89 has a downwardly facing recess 21a for containing the material 31a which forms the pocket 3(la for receiving the member M-1.
Housing 80 has a flat, upwardly facing annular surface 81 which is disposed beneath flange 71 of member 68 to provide a space for closely and slidably receiving therebetween the washer-like member 75 and also a ring-like member 82 which encompasses the member 75. With reference also to FIGURE 11, a pair of keys 83 are em bedded in the upper surface of member 82 in diametrically opposed, axially aligned relation for a purpose to appear. Such keys fit within respective elongated keyways 84 formed in the underside of the aforesaid flange 71. A pair of keys 35 are also embedded in the surface 81 of housing 88 (see FIGURE 11), such keys being in diametrically opposed, axially aligned relation and slidably fitting within respective keyways 86 formed in the underside of ring-like member 82. As illustrated in FIGURE 11, keyways 86 are radially offset from keys 83 exactly ninety degrees. Completing the assembly, housing 80 has a central upstanding boss 87 which is closely and slidably receivable within the central aperture 76 of the washer-like member 75.
From the foregoing, it will be understood that since ring-like member 82 is keyed to the fixed member 68, member 82 will be locked against rotation, although such member 82 will be rectilinearly movable relative to member 68 in a direction longitudinally of the keys 83 (or from left to right as viewed in FIGURE 10 or in the direction of the arrow X in FIGURE 11). Similarly, since housing 80 is keyed to the ring-like member 82, it will also be locked against rotation. Housing 80, however, is shiftable both with member 82 in the direction of the arrow X and also shiftable relative to the member 82 longitudinally of the keys 85 (or in the direction of the arrow Y in FIGURE 11).
Operation of the embodiment seen in FIGURE 10 will be similar to that heretofore disclosed in that the member M-l will be disposed in its pocket in the upper housing 80 and the member M2 disposed in its pocket in the lower housing 27a. Such members will then be clamped together to forceably abut their respective surfaces to be joined by elevating the lower housing as disclosed in the previously described embodiment.
Assuming shaft 72 to be rotating, it will be clear that housing 80 and therefore the member M-1 carried thereby will be held immobilized, with such member disposed in predetermined relationship with the fixedly supported member M-2, since the aperture 76 of the washer-like member 75 is concentric with the rotational axis of shaft 72. If now, however, the rotating shaft 72 is moved downwardly, the inclination of the pins 74 will cause the member 75 to shift transversely whereby it will rotate eccentrically of the shaft. This will cause movement of the housing 80 and of the member M-l supported thereby in a circular path, the size or diameter of which path is dependent upon how far down the shaft 72 is shifted. Accordingly, when the shaft 72 is in its lowermost position, the circular path through which the housing 80 and its member M-1 are shifted will be of maximum size. As the shaft 72 is elevated from such lowermost position, however, such path of movement will progressively contract to zero and with the members M1, M-2 in aligned relation upon disposition of the shaft in its uppermost position shown.
Removal of the fused together members M1, M-2 from the apparatus following hardening of their softened surfaces will readily be effected by lowering the plate 17a to thus separate the upper and lower member receiving housings and although not shown, a suitable ejector may be provided for ejecting the member M-1 from its pocket. Following removal of the fused together members M1, M-2, other members to be joined may be positioned in the apparatus as before described and the operations aforesaid repeated.
In view of the foregoing it will be apparent to those skilled in the art that I have accomplished at least the principal object of my invention and it will also be apparent to those skilled in the art that the embodiments herein described may be variously changed and modified, without departing from the spirit of the invention, and that the invention is capable of uses and has advantages not herein specifically described; hence it will be appreciated that the herein disclosed embodiment are illustrative only, and that may invention is not limited thereto.
1. The method of bonding a thermoplastic member to another member in predetermined alignment, which comprises pressing surfaces of said members against each other and simultaneously rubbing such surfaces through an amplitude of movement and during a time interval sufficient to soften the thermoplastic member surface by frictionally induced heat, thereafter progressively reducing the amplitude of rubbing movement and progressively bringing said members to said predetermined alignment until rubbing movement ceases with said members disposed in said predetermined alignment, and then holding said members in said predetermined alignment with said surfaces pressed against each other until the softened thermoplastic material hardens.
2. The method of claim 1 wherein said member rubbing movement is reciprocatory movement.
3. The method of claim 2 wherein said member rubbing movement takes place in a curved path.
4. The method of claim 1 wherein said member rubbing movement is such that all portions of one member decribe closed curved paths of identical magnitude relative to the other member.
5. Apparatus for bonding a thermoplastic member to another member in predetermined alignment, comprising body means supporting said members with respective surfaces pressed together, drive means having a pair of relatively movable parts which in a first position effect relative movement of said body means and consequently that of said members to rub said member surfaces against each other through a predetermined distance and during a time interval suflicient to soften the thermoplastic member surface by frictionally induced heat, in a second position said drive means parts holding said body means and consequently their supported members in said predetermined alignment, and in a position intermediate said first and second positions said drive means parts effecting relative movement of said body means to rub said member surfaces against each other through less than said predetermined distance, and means for effecting relative movement aforesaid of said drive means parts progressively from said first position to said second position through said intermediate position.
6. Apparatus for bonding in predetermined alignment a pair of workpieces one of which is formed of thermoplastic material, comprising a pair of bodies supporting respective workpieces with surfaces thereof pressed together and one of said bodies being mounted for bodily shifting movement in a circular path and the other being fixed against such movement, a rotatably mounted drive member adjacent said one body, and a driven member connected to said one body for rotation relative thereto and connected to said drive member for rotation therewith, said drive member and said driven member being mounted for relative shifting movement in a direction axially of the drive member axis and in one axial position of said drive member and said driven member the latter being disposed concentric with said drive member axis and holding said one body stationary with the workpiece supported thereby in said predetermined alignment with the other workpiece despite drive member rotation, in another axial position of said drive member and said driven member the latter being disposed eccentric with said drive member axis and transmitting drive member rotation to movement of said body in said circular path and consequent movement of the workpiece supported thereby relative to the other workpiece to soften said thermoplastic workpiece surface by frictionally induced heat.
7. The construction of claim 6 wherein said drive member has a pair of pins rotatable therewith and extending axially thereof, wherein said pins are disposed in spaced-apart parallel relation and are inclined with respect to the rotational axial of said drive member, and wherein said drive member is shiftable axially to dispose said driven member in its eccentric and concentric positions aforesaid.
8. Apparatus for bonding respective surfaces of thermoplastic members together, comprising a pair of bodies for supporting respective members and for clamping them in predetermined, surface-to-surface relation and one of said bodies being movable about an axis normal to said member surfaces, a rotatable crank member having a crank pin whose axis is inclined with respect to the crank members rotational axis and which intersects the latter, a connecting rod having a first portion journaled on said crank pin and a second portion pivoted to said one body in spaced relation to the axis of the latter, and means for shifting said crank member along its rotational axis between first and second positions, in said first position said connecting rod first portion being concentric with the rotational axis of said crank member to immobilize said connecting rod, said one body and the member carried by the latter despite rotation of said crank member, in said second position said connecting rod first portion being eccentric with the rotational axis of said crank member to transmit rotation of the latter to connecting rod movement together with reciprocatory movement of the member carried by said one body.
9. The construction of claim 8 wherein said bodies are relatively movable toward and away from each other to provide for insertion and removal of said thermoplastic members.
References Cited in the file of this patent UNITED STATES PATENTS Iohansson Oct. 19, 1895 Riordan Apr. 8, 1958 OTHER REFERENCES