US1962901A - Closure device for headers - Google Patents

Description

June 12, 1934. R. K. HOPKINS CLOSURE DEVICE FOR HEADERS Filed Aug. 19. 1932 N INVENTOR N Zafier/ Z fig 41 Patented June 12, 1934 UNITED STATES PATENT OFFICE 7 1,962,901 CLOSURE DEVICE ron HEADERS ware Application August 19, 1932, Serial No. 629,431 7 Claims.

This invention relates to headers or return bends, and relates more particularly to closure devices for headers or return bends.

The primary object of the present invention 5 is to provide a closure for a header or return bend so constructed as to be practically incapable of improper placement or fastening, whereby a tight closure may be readily obtained and the security of operation increased.

A further object of the invention resides in the provision of a self-centering securing means for such closure devices.

A still further object is to provide an improved form of deflector plug that cannot be incorrectly mounted in the header or return bend.

Other objects and advantages of my invention will be apparent from the following description, taken in conjunction with the accompanying drawing, which forms a part of this specification, and in which:

Figure 1 is a side elevation, partially in central vertical section, of a header or return bend embodying my invention;

Figure 2 is a front elevation partially in section, taken on the line 2-2 of Figure 1;

Figure 3 is a detail view of a part of the structure shown in Figures 1 and 2;

Figure 4 is an end elevation, partially in section, of a modified form of my invention;

Figure 5 is a front elevation of a still further modification; and

Figure 6 is a central vertical section taken on the line 66 of Figure 5.

Referring more particularly to the drawing, there is shown in Figures 1 and 2 a header or return bend 10 having a body portion 11 containing two tube bores 12 and 13, having tube seats 14 and 15, respectively, and a cross-over connection 16 between the tube bores. Opposed ears 17 and 18 are provided on the body portion 11 above each of the tube bores. With the exception of the dimensioning of the ears 1'7 and 18, to be referred to hereinafter, the construction of the parts so far described is more or less conventional. The body 11 of the header or return bend may be made by casting in the usual manner, or preferably by welding two individual forgings together at 19 as disclosed in my copending application Serial No. 655,719, filed Feb. 8th, 1933.

As shown more particularly in Figure 2, the ears 1'7 and 18 are so proportioned that the two slots 20 and 21 formed between the edges thereof are of unequal width, the slot 20 being shown as substantially wider than the slot 21. Plugs 22 are adapted to close the upper ends of the tube bores, fitting tightly against the machined seats 23 in the body 11 of the header. Each plug 22 is provided with two opposed ears 24 and 25, adapted to fit in the slots 20 and 21, respectively. As shown in Figure 2, the ear 24 is wider than the ear 25, so that the ear 24 will fit Within the slot 20, but cannot be inserted in the slot 21. Consequently, in inserting a plug, 22 in a plug seat 23, the plug can be inserted only in one position. The plugs 22 are shown as being of the well known deflector type. It is imperative that deflector plugs be inserted in the correct position, as otherwise the cross-over channel 16 would be very largely blocked by the curved surface of the plug. 01" course, when using ordinary plugs having their lower surface substantially flat, it is unimportant in which direction the plug may be inserted. For plugs of the latter type, therefore, the cars 24 and 25 and the slots 20 and 21 may be so proportioned that either ear may fit in either slot.

For the purpose of holding each'plug 22 firmly against its seat 23, there may be employed a yoke 30 having arms 31 and 32 fitting into holes 33 and 34 in the ears 1'? and 18;"respective1y. A screw 35 is threaded into the center of the yoke 30, and engages the center or" the plug 22. By tightening the screw 35, the yoke 30 is raised so that the arms 31 and 32 engage the upper ends of the holes 33 and 34, respectively, thereby causing the lower end of the screw 35 to press against the plug 22 and hold it firmly in place.

With yokes of this character as commonly employed heretofore, it has been possible for the lower end of the screw 35 to be seated at some point other than thecenter of the plug 22. This has occasionally resulted in slippage of the plug 22 when in use under high pressure, thereby causing leakage and danger of fire. In order to avoid this contingency, I provide means for insuring the centering of the screw 35 on the plug 22.

As shown more particularly in Figure 3, the lower end of the screw 35 is rounded to form a tip 36 having the contour of a segment of a sphere. A recess 37 is machined into the center of the top of the plug 22, the bottom or seat 38 ofthe recess being spherically shaped to conform to the tip 36 of the screw 35, and the upper portion or approach 39 of the recess being preferably in the form of a frustum of a cone having its lower end substantially equal in area to the area of the seat 38 and its upper end considerably larger than the seat 38. If the screw 35 no yoke 30, are vertical.

of the yoke.

'34 of corresponding widths.

be tightened when its spherical tip 36 is within the conical approach 39, the yoke will be raised as the tip 36 engages in the conical approach 39, and at the same time, the screw will move toward the center of the recess 3'7 until the tip 36 is seated firmly in the spherical seat38 This construction of thescrew 35 andthe; recess 37 insures accurate centering of the screw 35 on the plug 22. The accuracy of the centering depends upon the accuracy of the correspondence of the diameter of screw tip 36 and the diameter of the spherical seat 38, thus by takingc-thernece essary care in the making of screw tip 36 and spherical seat 38 an accuracy of centering well beyond anything heretofore attainable is possible. Because of the slope of conical approach 39 tip 36 will not grip and bind but will move down conical approach 39 to spherical seat 38,

thus centering itself as Well as the whole of screw 35 relative to plug 22. This centering of screw 35 is made possible by the fact thatarms 31 and 32 or" yoke 30 slide relative to cars 17 ande18 astip 36 moves down conical approach 39 and allows screw. 35 to move to the centering position. It will be understood. that the approach .39, instead of being conical, might be made as a continuation of the, spherical surface of the seat 38, or in some other form. The im portant thing, is that the approach 39. should constitute an inclined surface adapted to guide theflscrew 35. toward the seat 38. Similarly, the tip 36. need not be spherical in shape, but may have anyv contour adapted to slide along the approach 39, the seat 38 having preferably. the same. contour as the tip 36.

In order that the screw 35 may atall times be presented to the plug 22 withinthe conical approach 39, I providea stop 40 on the yoke arm 32. This stop 40 is adapted to engagev the innerwall of the car 18, and thusroughly centersthe screw 35. above the conical approach 39. It will be understood that headers of. this. character are usually mounted on a still in the position shown in Figure 2, in such manner that the arms ofv the Obviously, the stop. 40 cannotserve to center theyoke 30 unlessthe stop 40. isin engagement with the inside wall of. the ear coacting therewith, This engagement will be provided automatically by gravity due, to the weight of the yoke 30, which is quite considerable,

if, the yoke be inserted in such manner ,that the arm carryingthe yoke stop 40 is the lower arm According to my inventiornl preferably correlate the dimensions of the yoke arms and their cooperating holes in the ears 1'7 and 18,

sothat the yoke 30 can only be inserted with the stop 40 in the desired position. I

In the modification of my invention shown in Figures 1 and 2, I accomplish this latter result by making one of thearms of the yoke narrower than the other arm,an d making the slots 33and As shown in Figure 2, the arm 31 and its cooperating slot 33 are made narrowerthan the arm 32 and the slot 34. It will be obvious, however, that either arm couldbe thewider one, provided the slots 33.and 34 were correspondingly arranged so that the yoke stop 40 would always be on the lower arm.

In Figure 4, I disclose a modification in which the same result is accomplished in a somewhat different fashion. In this figure, the yoke 30 is constructed similarly to the yoke 30 shown in Figure 2, except that the two arms 31 and. 32' are symmetrical, aside from the location of the stop 40' on the arm 32*. The yoke holes 33' and 34' are located in the ears 17 and 18 respectively, and are adapted to cooperate with the arms 31' and 32, respectively. The yoke holes 33' and 34' may be of the same width, but as shown in Figure 4, the yoke hole 33 has a height greater than that ofthe .yokehole 34. In insertingthe yoke, itisnecessary to slide one of the. arms through its yoke hole considerably past the center position, and then tilt the yoke and move it backward so that the other yoke arm enters its aperture. With the dimensioning of the yoke arms 31 and 32 andthe holes 33' and 34 shown in Figure 4, it will be apparent that the yoke 30' can only be inserted by introducing the arm 31' into the aperture 33'.- If it were attempted to reverse the yoke, the rounded bottom portion of the yoke would strike against the bottom of the aperture 34' before the insertion of the yoke could be completed.

It will be obvious that the yoke constructions shown in Figures 2 and 4 are therefore irreversible in character, so that the yoke can only be, inserted in such position that the force of gravity insures proper engagement of the yoke stop with the cooperating ear. I have thus obviated the possibility of a careless workman, in replacinga yoke after cleaning, failing to center the. yoke so that the screw 35- will enter the self-centering conical approach 39.

In Figures 5 and 6.1 have shown the self-centering feature of my invention as applied to a modified form of header closure. The. closuredevice shown in these figures is of the wellknown set collar type. The header 50.;is provided witha plug seat 51 which is closed by a plug 52. A counter bore 53 is formedin the upper portion of the header and is cut away as shown at54tto permit the entrance of a set collar 55 and the plug 52. The plug 52 may be provided with a lug 56 to facilitate its insertion and removal. A screw57 is'threaded into the center of thecollai' 55 and isadapted to engage the plug 52. 'The collar 55 is provided with .a shoulder 58.. which engages the upper side ofthe counter bore 53 and provides the necessary fulcrum to permit tightening of the screw 5'? against the plug .52.

According to my invention, I provide the screw 57 with a rounded tip. 60 and the plug 52 with a self-centering recess 61, exactlysimilar to the. tip 36 and recess 37 shown in Figure 3 and described above in connection with other embodiments .of

.my invention. In order to insure the entry of the screw 57 within the conical approach .62 of the recess 61, I make the collar 55 and the counter bore 53 of such dimensions that the collar 55 can move within the. counter'bore only to an extent which will not permit the screw .57 to get outside of the range of the conical approach 62. It will thus be apparent that the correlation of the collar 55 and the counter bore 53 performs the same function as the yoke stop 40shown in Figure 2.

It will be obvious to those skilled in the ar't that many modifications and changes may be made in .my invention without departing from the spirit thereof, and I desire to bellimited, therefore, only by theprior art and the scope of the appended claims. I claim:

1. A closure device for a header comprising a plugadapted to fit tightly in a seat in the-header, a recess formed in the outer face of saidplug,said recess having 'a screw seat and an approach thereto so inclined that when a screw tip is urged thereagainst said screw tip will movedown said approach to said screw seat, a positionable yoke adapted to bear against a portion of the header, a screw threaded in said yoke, said screw having a tip of substantially the same diameter as said seat, means on said yoke adapted to cooperate with said header to position said yoke with said screw tip in approximate alignment with said screw seat within said inclined approach, said yoke being slidable relative to said header whereby when said screw tip is urged against said approach said yoke will move relative to the header to permit the lateral movement of the tip required to seat said tip in said screw seat.

2. A closure device for a header comprising a plug adapted to fit tightly in a seat in the header, a recess in the outer face of said plug, said recess having a screw seat and an approach thereto so inclined that when a screw tip is urged thereagainst said screw tip will move down said approach to said screw seat, a yoke having arms adapted to fit in apertures in the sides of the header, a screw threaded in said yoke having a tip of substantially the same diameter as said screw seat, a stop on one of the arms of said yoke adapted to cooperate with the header to position said yoke with said screw tip in approximate alignment with said screw seat and within said inclined approach, said arms of said yoke being slidable in said apertures whereby said yoke moves relative to said header to accurately align said screw with said screw seat said screw tip is urged down said inclined approach.

3. A closure device for a header comprising a plug adapted to fit in a seat in the header, a recess in the outer face of said plug, said recess having a screw seat and an approach thereto so inclined that when a screw tip is urged thereagainst said screw tip will move down said approach to said screw seat, a yoke having arms adapted to fit in apertures in the sides of the header, a screw threaded in said yoke adapted to seat in said screw seat, a stop on said yoke adapted to engage the header to position said screw in approximate alignment with said screw seat and within said approach, said yoke being so proportioned with respect to said header apertures as to be capable of insertion in the header in only one direction.

4. A closure device for a header comprising a plug adapted to fit tightly in a seat in the header, a recess formed in the outer face of said plug, said recess having a screw seat and an approach thereto so inclined that when a screw tip is urged thereagainst said screw tip will move down said approach to said screw seat, a yoke having arms of unequal width adapted to fit in apertures in the header walls, a screw threaded in said yoke having a tip of substantially the same diameter as said screw seat, and a stop on one of said arms adapted to engage the header walls to position said yoke with said screw tip in approximate alignment with said screw seat and within said inclined approach, whereby when said screw is screwed towards said plug and said screw tip moves down said inclined approach to said screw seat said yoke will move relative to the header walls as required to accurately align said screw and screw tip with said screw seat. A

5. A closure device for a header comprising a plug adapted to fit in a seat in the header, a recess formed in the outer face of said plug, said recess having a seat for a screw and an inclined approach thereto, a yoke having arms adapted to fit in apertures in the sides of the header and a screw threaded in said yoke with its end adapted to seat in said screw seat, said yoke being so proportioned with respect to the header as to be capable of insertion in the header in only one direction and said inclined approach being disposed at such an angle as to assurevupon urging of said screw against said inclined approach the alignment of said screw with said screw seat by reason of the movement of said screw down said inclined approach and the movement of said yoke and screw towards the center of said screw seat, whereby said screw will be caused to engage the plug at the screw seat when the screw is turned into tight engagement with the same.

ROBERT K. HOPKINS.

Images