US2807855A

US2807855A - Bracelet end attachment

Info

Publication number: US2807855A
Application number: US437065A
Authority: US
Inventors: Rodriguez Emil
Original assignee: Jacoby Bender Inc
Current assignee: Jacoby Bender Inc
Priority date: 1954-06-16
Filing date: 1954-06-16
Publication date: 1957-10-01
Anticipated expiration: 1974-10-01

Description

Oct. 1, 1957 E. RODRIGUEZ 2,807,855

' BRACELET END ATTACHMENT FiledJune 16, 1954 2 sheets-sheet 1 PM i H Z1 15. 5 I INVENTOR. 70 54 56\ 8 52 60 50 [m1/ Roonguez 54 BY 115.4 K I Oct. 1, 1957 E. RODRIGUEZ 2,307,855

BRACELET END ATTACHMENT I Filed June 16, 1954 2 Sheets-Sheet 2 [0 I006 50

96b

46b

42d 96d 100d 76 INVENTOR. EmI/ R0 dr/guez I04 I006 50 I I512 A iiorneys.

'lugs.

United States Patent BRACELET END ATTACHMENT Emil Rodriguez, New York, N. Y., assignor to Jacoby- BYender, Inc., New York, N. Y., a corporation of New Application June 16, 1954, Serial No. 437,065

18 Claims. (Cl. 24-265) The present invention relates to a bracelet end attachment adapted to be inserted between spaced watch lugs and, within limits, to automatically adapt itself to variations in that space.

Many watches, and particularly mens watches, are provided with pairs of spaced lugs on each end, between which lugs the ends of a watch strap or bracelet are secured, usually by means of a spring pin passing through a hollow tubular part in the bracelet end and having tips adapted to be received in apertures formed in the watch There are a multitude of sizes and styles of watches, and a corresponding variation from watch to watch in the distance between the watch lugs. It is obviously impractical for a manufacturer or retailer of watch bracelets to make or stock bracelets in every style and in every possible width. It is not even feasible to make bracelets in a limited number of widths, as is done, and provide end attachments for the bracelets which are of exactly the right sizes to correspond to all of the various spacings between the watch lugs. These end attachments are usually an integral part of the bracelet, built thereinto by the manufacturer, and any such approach would require each retailer to maintain a tremendous inventory on the chancethat a would-be purchaser might have a watch the lugs of which are spaced from one another by an unconventional distance.

On the other hand, it is most undesirable appearancewise and functionally that when the bracelet is attached to the watch its ends should slide back and forth between the watch lugs, as would occur if the end attachment were narrower than the space between those lugs. Any gap between the bracelet end and the watch lugs is unsightly, 1

and the relative sliding of the watch and bracelet end gives rise to a sloppy feeling, and has a tendency to pinch the skin of the wearer.

In the past this problem usually has been met by providing bracelets with end attachments in a limited number of standard widths, and by requiring the retail jeweler, when the bracelet is sold, to fit that bracelet to the customers watch and to cut or file down the end attachments so as to give it a width corresponding accurately r to the space between the lugs on the watch of that particular customer. This is a troublesome task, particularly in view of the fairly low profit made by the retailer on an individual sale. Furthermore, this expedient has not entirely solved the inventory problem of the retailer, since he still must stock bracelets of a given style having a plurality of different width end attachments.

It therefore is not surprising that it has been proposed in the past that self-sizing end attachments be provided. These have usually taken the form of a fixed end attachment having a minimal width, with members resiliently projected out from each end thereof so as to bridge the gap between the fixed portion of the end attachment and the lugs of the particular watch to which the-bracelet is adapted to be secured. Numerous such constructions have 1 been devised, but none of them have met with any real measure of public acceptance or permanency, primarily Patented Oct. 1, 1957 because they are extremely unreliable. The tendency of the bracelet to move toward one lug or the other was resisted only by the necessarily weak spring acting between the movable members on the end attachment. The member pointing in the direction in which the bracelet moved would slide inwardly upon the exertion thereon even of minimal forces, the member on the other side of the end attachment was carried along, and consequently one of the main drawbacks to the use of fixed end attachments narrower than the space between the watch lugs, to wit, the relative sliding of bracelet and watch, while somewhat minimized, was not avoided by such structures. In addition, when the members resiliently urged outwardly from the fixed portion of the end attachment were themselves employed to engage with the watch lugs, dispensing with the use of a conventional spring pin, the above described action of the prior art self-sizing devices often resulted in separation of the bracelet from the watch, obviously an inadmissible situation.

A further drawback to the use of self-sizing end attachments of the prior art was that they were fairly diflicult to manipulate, and thus made it difficult if not impossible for the average person to remove or attach a bracelet himself. This, of course, placed a burden on the retailer which, while perhaps not as onerous as the previous necessity for cutting or filing the end attachments to the proper width, was nevertheless undesirable. It must be realized that, under these circumstances, and apart from the time actually involved in attaching the bracelet to the watch, a potential sale would be lost if the would-be customer did not happen to have with him the watch with which the bracelet was to be used.

A further disadvantage characteristic of the prior art structures, important primarily from an appearance point of view, was that the bracelet would not always be centered between the watch lugs, but might assume a position closer to one lug than to the other.

The structure of the present invention avoids all of the above disadvantages, and involves a mechanism which,

while necessarily somewhat more complex than those sug-' gested in the prior art, nevertheless is eminently capable of manufacture and assembly at such an extremely low cost as to be commercially practical. To this end the two members resiliently urged outwardly from opposite ends of the fixed portion of the bracelet end attachment are connected to a movement-equalizing linkage, by means of which the positioning of one member relative to the fixed portion of the end attachment will necessarily cause a corresponding positioning of the other member. As a result, the bracelet end attachment will always be centered between the watch lugs. This movement-equalizing linkage, when properly designed, can also serve two other extremely important functions. First, the linkage is so designed as to resist and eifectively prevent inward movement of the members when all but the strongest inward pressure is applied only to one of those members. Consequently any tendency of the bracelet to slide from side to side relative to the watch is practically eliminated. Second, the same linkage will also function, when the resilient means serving to urge the'members outwardly is active on those members through the intermediation of tion, preferably housed substantially completely within the fixed portion of the attachment. When the securing element is thus engaged with the movable members, theattachmentmay readily be inserted between the watch lugs, andwhen the attachment is properly positioned and the. securing element is moved to inoperative position the members are released and are urged outwardly by the resilient means into engagement with the watch lugs, thus performing their self-sizing and centering function. Hence it is a simple matter, well within the capabilities even of the mechanically unskilled, to secure to a watch bracelet fitted with the end attachment of the present invention.

To the accomplishment of the above, and to such other objects as may hereinafter appear, the present invention relates to the structure of a bracelet end attachment as defined in the appended claims, and as described in this specification, taken together with the accompanying drawings, in which:

Fig. l is athree-quarter perspective view of a bracelet fittedwith the end attachment of the present invention and showing the manner in which it is adapted to be secured to a watch;

Fig. 2 is a top plan view, partially broken away, of the end. attachment with the ornamental top shell removed;

Fig. 3 is a bottom plan view thereof, with the linkage housing cross sectioned;

Fig. 4 is a cross sectional view taken along the line 4--4 of Fig. 2;

Fig. 5 is a view similar to Fig. 2 but showing the movable members in fully telescoped condition andwith the securing element in operative position;

Fig. 6 is a fragmentary exploded view, partially in cross section, showing the linkage and resilient means of the embodimentof Figs. 1-5;

Fig. 7 is a view similar to. Fig. 3 but showing another embodiment of the present invention;

Fig. 8 is a cross sectional view taken along the line 88 of Fig. 7; and

Figs. 9, 10, 11 and 12 are views similar to Fig. 2 but showing four other embodiments of the present invention.

Referring first to the. embodimentsof Figs. l-6, the end attachment comprises a base plate 2 oneend 4 of which is in hollow tubular form, the other. end having a rear protrusion 6 provided with an elongated slot 8, another slot being formed in the other side of the rear portion of the base plate 2, these slots-being provided so that an X-type resiliently. expandible bracelet generally designated 12 may be secured thereto in conventional manner. An ornamental shell 14 is adapted to cover the plate 2 and the mechanism thereon, the ornamentation on the shell 14 preferably corresponding to the ornamentation of the top shells 14a on the bracelet 12. Itwill be understood, of course, that any other type of bracelet or strap-could be employed in place of the specific bracelet 12 illustrated, the base plate 2 being modified in conventional manner so as to be attached thereto.

The tubular part 4 of the base plate 2 is of predeten mined minimal width such as to fit between lugs 16 on a watch case 18 when those lugs 16 are comparatively closely spaced. A pair of

members

20 and 22 are provided telescopable within the hollow tubular portion 4 (see Fig. 5) and movable outwardly beyond the sides 24 and- 26 thereof. In the form shown in Figs. 1-5, each of these members is formed from a single sheet of metal or the like rolled or bent to define a hollow tube, a conventional spring securing pin 28 (see Fig. 1) being adapted to be passed therethrough and through the hollow tubular part 4 of the base plate 2 so that the tips 30 of the spring pin 28 may be received within apertures 32 in the watch lugs 16. In order to provide access to the spring pin when the bracelet is to be removed, the outer endof one of the members, here shown as the member 22, is provided with a slot 34. In addition, the inner ends of each of the

members

20 and 22 are provided with

slots

36 and 38 respectively. Each of the

members

20 and 22 is provided with rearwardly extending

plates

40 and 42 respectively which are slidable along passages 44 (see Fig. 4) defined between the base plate 2 and the overhanging end of the tubular part 4. Ex-

tending downwardly from the central portion of the lower side of the base plate 2 is a housing generally designated 46 the upper portion of which may be open, as shown in Figs. 2 and 4. The bottom wall 48 of the housing 46 is provided with a slot 50 along which pin 52 slides, the slot 50 being oriented substantially at right angles to the length of the tubular part 4, that is to say, perpendicular to the width of the end attachment. A pair of

arms

54 and 56 are provided respectively with hubs 5S and 60 freely rotatably fitted on the pin 52, and a hellcal spring 62 is wound about the pin 52 inside the

hubs

58 and 60, the ends 96 and of that spring 62, after the spring has been stressed, being received within

notches

64 and 66 formed respectively in the upper and lower surfaces of the hubs 58 and 6t), the spring 62 being active to urge the

arms

54 and 56 to rotate away from one another. The pin 52 may be provided with a head 68 in order to retain the hubs 58 and.60 on the pin 52 and the spring ends in their

respective notches

64 and 66. As may best be seen from Figs. 4 and 6, the

arms

54 and 56 are adapted to ride along the bottom wall 48 of the housing portion 46 and extend into the hollow tubular portion 4. The arms, at their ends, are provided respectively. with trunnions 70 and 72' adapted to be received respectively in the slots36 and 38 at the inner ends of the movable members 29 and 22, thus defining a pivotal operative connection between each of the members-20, 22 and a

corresponding arm

54, 56. The tendency of the spring 62 to separate the

arms

54 and 56 will therefore cause the

members

20 and 22 to slide outwardly beyond the

sides

24 and 26 respectively of the tubular part 4, thus in efiect extending the width of the end attachment so as to correspond to the spacing between the particular watch lugs 16 involved. When this occurs, the pin 52 will slide along the slot 50 in the direction of the tubular member 4.

If pressure is exerted on the

members

20 and 22 so as to tend to move them into the tubular part 4, thus contracting the effective width of the attachment, this pressure will cause the

arms

54 and 56 to swing toward one another against the action of the spring 62, the pin 52 sliding along the slot 50 in a direction away from the tubular part 4, and when pressure is released from the members 20 and- 22 they will once again, under the influence of the spring 62, resiliently telescope outwardly to an extent limited only by the length of the slot 50, which restricts the degree towhich the pin 52 can slide toward the tubular part 4.

Because of the orientation of the slot 50, the pin 52 is restricted from movement in a direction widthwise of the attachment. Hence the

members

20 and 22, when operatively connected to the

arms

56 and 54 respectively, must be correspondingly positioned relative to the tubular portion 4. As a-result, the part .of the attachment secured to the bracelet 12 will always be centered between the watch lugs 16 when theouter ends of the

members

20 and 22 are in engagement withthose lugs.

It will be noted that the

arms

54 and 56 extend at an angle to the direction of-movement of the

members

20 and 22. As a result, when a given force is exerted upon the

members

20 and 22 tending to cause them to telescope inwardly with respect to the tubular part 4, only a component. of that force will be exerted on the

arms

54 and 56 as a moment tending to cause them to pivot toward one another. It isonly this moment which is active on the spring 62 to cause the latter to wind up. That com.- ponent of the force exerted on the member 20 which is not applied to the spring 62 is partially opposed by an opposite and substantially equal component, of the force exerted on the member-22,"the remainder of those components acting aidingly to slide the pin 52 along the slot 50. Consequently, for a given resistance to movement of the

members

20 and 22, a weaker spring 62may be employed than would be the case if the spring were directly active on the

members

20 and 22 in the manner suggested by the prior art. Conversely, employment of a spring 62 of conventional strength will result in increased resistance of the

members

20 and 22 to inward movement when compared to the structures of the prior art. The magnitude of the components of the forces exerted on the

members

20 and 22 which will be applied tothe spring 62 will increase as the

arms

54 and 56 approach one another. At the same time the spring 62, being more and more wound up, will resist those forces to an increased degree. These effects at least to some extent compensate for one another, so that the resistance to inward movement of the

members

20 and 22 is much more independent of their position relative to the tubular part 4 than would otherwise be the case.

That component of the inward force exerted on the

members

20 and 22 which does not act on the spring 62 plays a further extremely important role. Let us assume that inward force is exerted only on the member 20, as would be the case if the bracelet, after being attached to the Watch 18, tended to slide toward the watch lug 16 with which the member 20 was in engagement. One component of this force would tend to cause the arm 54 to pivot toward the arm 56. Another component thereof, however, would be exerted on the pin 52 in the direction in which the arm 54 extends. Part of this latter force component would tend to cause the pin 52 to slide along the slot 50 away from the tubular part 4, but another part thereof would tend to force the pin 52 against the side of the slot 50. This last component would be appreciable, its precise magnitude depending on the angularity of the arm 54 relative to the slot 50, the pin 52 will resist sliding, and consequently the arm 54 will not pivot. Hence the member 20 will strongly resist inward telescoping movement. It is only when inward pressure is exerted simultaneously on the

members

20 and 22 that the pin 52 will freely slide along the slot 50, the force components tending to urge the pin 52 against the sides of the slot 50 cancelling one another out in that latter situation. Hence the linkage here disclosed has the additional extremely important efiect of strongly resisting inward force exerted on only one of the

members

20 and 22. Therefore the end attachment of the present invention will not only initially center itself between the watch lugs 16, but will reliably remain thus centered even when extremely appreciable forces are exerted thereon tending to move it toward one watch lug 16 or the other.

A securing element in the form of an arm 74 is pivotally mounted on the base plate 2 at 76 and is adapted to overlie the head 68 of the pin 52, thus serving to retain the pin 52 in position. The arm 74 is provided with a tab 78 extending downwardly through an arcuate slot 80 in the base plate 2, manual manipulation of the tab 78 causing the arm 74 to be moved between its inoperative position shown in Fig. 2 and its operative position shown in Fig. 5 The arm is provided with

teeth

82 and 84 engageable with corresponding

teeth

86 and 88 on the

plates

40 and 42 respectively when the

members

20 and 22 are substantially fully telescoped Within the tubular part 5, the arm '74 thus retaining the

members

20 and 22 in their retracted position, the effective width of the attachment thus being maintained at its minim-a1 value. This facilitates insertion of the attachment between the watch lugs 16 and the securing of the spring pin 28 to those lugs 16. After this has been accomplished, the tab 78, accessible from beneath the attachment, is moved along the slot 80 so that the arm 74 is pivoted to its inoperative position releasing the

teeth

86 and 88 on the

plates

40 and 42 respectively, the spring 62 then being permitted to unwind soas to cause the

members

20 and 22 to telescope out-

v plates

40 and 42 so as to prevent the

members

20 and 22 from sliding completely out of the tubular part 4.

The embodiment of Figs. 7 and 8 illustrates an attachment employing movable members 20 and 22' of a specifically dilferent type from those employed in the embodiment of Figs. 1-6. In Figs. 7 and 8 those members are solid bars telescopable with respect to the fixed tubular portion 4 and carrying tips 30' at their ends, those tips 30' being adapted for direct engagement with the apertures 32 in the watch lugs 16, thus dispensing with the necessity for the employment of a separate spring pin 28. It will be understood that the tipped members 20' and 22 could be substituted for the

tubular members

20, 22 in all of the other illustrated embodiments.

The embodiment of Figs. 7 and 3 also discloses a specifically different linkage between the members 20' and 22. The base plate 2 is provided with the elongated slot 59 oriented substantially perpendicular to the width of the attachment, and each of the movable members 20' and 22 are provided with

plates

40 and 42 slidable therewith, each of those plates being provided respectively with an

elongated slot

92 and 94 respectively, each of those slots being inclined approximately 45 degrees with respect to the slot 50 and those slots at least partially overlapping, the pin 52 passing through the overlapping portions of the

slots

92 and 94 and sliding along the slot 50. The coil spring 62a has one end 96a engaged against a tab 98 extending up from the base plate 2, the other end 106a of the spring 62a bearing against the pin 52 between the plates 40 and 42' and being active to urge the pin 52 toward the tubular part 4. It will be appreciated that the mode of operation of the embodiment of Figs. 7 and 8 will be substantially similar to that of the previously disclosed embodiment. The members 20' and 22' are connected together by means of the

slots

92 and 94 in their

respective plates

40 and 42 and by the pin 52 motion of which laterally of the attachment is effectively prevented, so that each of the

members

20 and 22 will always be correspondingly positioned relative to the tubular part 4, thus providing for centering the attachment at all times. The inclination of the

slots

92 and 94 will serve to resist inward movement of the members 20 and 22' when inward force is exerted only on one of those members. The spring 62a will be active to cause the members 2t? and 22' to assume its outward telescoped positions, and only a portion of the inward force exerted on the members 20' and 22 will be applied to the spring 620.

The embodiment of Fig. 9 is similar to that of Figs. l-6 except that the spring 6211, instead of being wound around the pin 52, is instead confined within the housing portion 46b, one end 965 thereof being active against an end of the housing 46b and the other end 19Gb thereof being active against the

hubs

58 and 60 of the

arms

54 and 56 so as to urge those hubs, along with the pin 52, toward the tubular part 4. The embodiment of Fig. 10 is similar to that of Figv 9 except that a specifically different location of the spring is disclosed, that spring being designated 620, the end 960 thereof bearing against a side of the housing 46c and the end a thereof bearing directly against a tab 191 on one of the arm links.

InFig. 11 a spring 62d is employed having ends 96d and'l tltld active on the movable members 20 andlZ2 independently of the linkage which connects them, those spring ends 96d and 100d engaging the innerends of the plates 40a and 42d slidable respectively with the

members

20 and 22. A spring 62d may also be employed directly on the.

arms

54 and 56 so as to ensure that the

trunnions

70 and 72 will remain within the

slots

36 and 38 respectively, but the spring 62d may be con siderably weaker than the spring 62 in the embodiment of Figs. 1-6. Of course, a spring 62d of normal strength could be employed, the

springs

62d and 62d thus assisting one another in urging the

members

20 and 22 outwardly.

In the embodiment of Fig. 12 a tension spring 62:: is employed, one end 96a of which is secured to a pin 102 extending up from the base plate 2, the other-end ltltle of which is secured to a pin 104 projecting from one of the

hubs

58 or 6%, the spring 62a, like the springs 62a, 62/) and 62c, being active to urge the linkage to move so that

thearms

54 and 56 pivot away from one another and the pin 52 moves along the slot 50 toward the tubular part 4.

From the above description it will be apparent that a simple and readily constructed and assembled end attachment has been devised which will reliably and positively provide a self-sizing feature, which will permit the use of weaker springs than have previously been employed without sacrifice of operating characteristics or, conversely, will provide improved operating characteristics with springs of conventional strength, and which will effectively retain the attachment centered between the lugs 16 of the watch 18 to which it may be attached against all normal dislocative forces which may be applied thereto.

While numerous detailed embodiments of the present invention have been here disclosed, it will be appreciated that they are merely illustrative of the many forms which this invention may take, all within the spirit thereof as defined in the following claims.

I claim:

1. A bracelet end attachment comprising a base having a part with sides adapted to be inserted between spaced watch lugs, a pair of longitudinally extending members on said base movable inwardly and outwardly with respect to the sides of said base part substantially in the direction of their 'length. resilient means active on said members to urge them outwardly, and a linkage operatively connected between said members and effective to require simultaneous movement of both members inwardly or outwardly with respect to said base part.

2. In the attachment of claim 1, a securing element mounted on said base so as to be movable between operative and inoperative position, said securing element when in operative position engaging said members when the latter are positioned inwardly with respect to the sides of said base part and retaining said members in that position.

3. A bracelet end attachment comprising a base having a part with sides adapted to be inserted between spaced watch lugs, a pair of longitudinally extending members on said basemovable inwardly and outwardly with respect to the sides of said base part substantially in the direction of their length, resilient means active on said members to urge them outwardly, and a securing element mounted on said base so as to be movable be tween operative and inoperative position, said securing element when in operative position engaging said member when the latter are positioned inwardly with respect to the sides of said base part and retaining said members in that position.

4. The attachment of claim 1, in which said linkage is so constructed and arranged as to resist inward movement of said members upon the application of inwardly directed force to only one of said members.

5. The attachment of claim 1, said linkage comprising elements connected respectively to and movable with said members, and a linking means operatively between said elements and movable substantially only in a direction perpendicular to the length of said members, said elements and, said means being operatively connected so that said means moves toward and away from said body part as said members move outwardly and inwardly with respect to said body part, whereby inward movement of said members is resisted upon the application of inward force to only one of said members.

6. The attachment of claim 1, in which said linkage comprises a pair of arms pivotally connected respectively to said members and oriented .at an angle with respect to the length of said members, and a movement-equalizing connection between said arms, whereby inward movement ofsaid members is resisted upon the application of inward force to only one of said members.

7. The attachment of claim 1, in which said linkage comprises a pair of arms pivotally connected respectively to said members and oriented at an angle with respect to the length of said members, a pin pivotally connecting said arms to one another in overlapping relation, and means ,for preventing movement of said pin in the direction of movement of said members, whereby inward movement of said members is resisted upon the application of inward force to only one of said members.

8. A bracelet end attachment comprising a base, a fixed tubular part on said base adapted to be inserted between spaced watch lugs, a pair of longitudinally extending members telescopable into and out of opposite sides of said tubular part substantially in the direction of their length, resilient means active on said members to urge them outwardly, and a linkage operatively connected between said members and effective to require simultaneous movement of both members inwardly or outwardly with respect to said tubular part.

9. In the attachment of claim 8, a securing element mounted on said base so as to be movable between operative and inoperative positions, said securing element when in operative position engaging said members when the latter are positioned inwardly with respect to the sides of said tubular part and retaining said members in that position.

10. The attachment of claim 8, said linkage comprising elements connected respectively to and movable with said members, and a linking means operatively between said elements and movable substantially only in a direction perpendicular to the length of said members, said elements and said means being operatively connected so that said means moves toward and away from said body part as said members move outwardly and inwardly with respect to said body part, whereby inward movement of said members is resisted upon the application of inward force to only one of said members.

11. The attachment of claim 8, in which said linkage comprises a pair of arms pivotally connected respectively to said members and oriented at an angle with respect to the length of said members, a pin pivotally connecting said arms to one another in overlapping relation, and means for preventing movement of said pin in the direction of the length of said members, whereby inward movement of said members is resisted upon the application of inward force to only one of said members.

12. The attachment of claim 11, in which said memhers have slots opening outwardly from the inner ends thereof, and in which said arms have trunnions receivable in said slots, said trunnions and slots defining the pivotal operative connection between said arms and said members, whereby said operative connections may be effectuated by sliding said members inwardly through said tubular part until said slots receive said trunnions.

13. The attachment of claim 11, in which said members have slots opening outwardly from the inner end thereof, and in which, said arms have trunnions receivable in said slots, said'trunnions and slots defining the pivotal operative connection between said arms and said members, whereby said'operative connection may be'effectuated by sliding said members inwardly through said tubular part until said slots receive said trunnions, said resilient means being active on said members via said linkage, whereby only a fraction of any inward force which may be exerted on said members is applied to said resilient means.

14. A bracelet end attachment comprising a base, a first tubular part on said base extending substantially in a straight line from side to side thereof and adapted to be inserted between spaced watch lugs, said tubular part having a slot therethrough extending longitudinally thereof between its interior and a surface of said base, a pair of longitudinally extending members telescopicable into and out of opposite sides of said tubular part substantially in the direction of their length, projections carried by said members and extending through said slot so as to overlie said base surface, resilient means active on said members to urge them outwardly, a linkage operatively connected between said members and efiective to require simultaneous movement of both members inwardly or outwardly with respect to said tubular part, and a securing element mounted on said base surface so as to be movable between operative and inoperative positions, said securing element when in operative position engaging said projections when said members are positioned inwardly with respect to the sides of said tubular part and retaining said members in that position.

15. The attachment of claim 14, said linkage comprising elements connected respectively to and movable with said members, and a linking means operatively between said elements and movable substantially only in a direction perpendicular to the length of said members, said elements and said means being operatively connected so that said means moves toward and away from said body part as said members move outwardly and inwardly with respect to said body part, whereby inward movement of said members is resisted upon the application of inward force to only one of said members.

16. The attachment of claim 14, in which said linkage comprises a pair of arms pivotally connected respectively to said members and oriented at an angle with respect to the length of said members, a pin pivotally connecting said arms to one another in overlapping relation, and means for preventing movement of said pin in the direction of the length of said members, whereby inward movement of said members is resisted upon the application of inward force to only one of said members.

17. The attachment of claim 16, in which said members have slots opening outwardly from the inner ends thereof, and in which said arms have trunnions receivable in said slots, said trunnions and slots defining the pivotal operative connection between said arms and said members, whereby said operative connections may be efiectuated by sliding said members inwardly through said tubular part until said slots receive said trunnions.

18. The attachment of claim 16, in which said members have slots opening outwardly from the inner end thereof, and in which said arms have trunnions receivable in said slots, said trunnions and slots defining the pivotal operative connection between said arms and said members, whereby said operative connection may be eflectuated by sliding said members inwardly through said tubular part until said slots receive said trunnions, said resilient means being active on said members via said linkage, whereby only a fraction of any inward force which may be exerted on said members is applied to said resilient means.

References Cited in the file of this patent UNITED STATES PATENTS 863,254 Bishop Aug. 13, 1907 1,128,719 Poppenhusen Feb. 16, 1915 1,172,482 Perkins Feb. 22, 1916 1,999,707 Spiegel Apr. 30, 1935 2,653,369 Rodriguez Sept. 29, 1953 FOREIGN PATENTS 102,023 7 Great Britain June 22, 1916 41,337 Sweden Sept. 13, 1916