US1086737A - Flexible stay-bolt. - Google Patents

Flexible stay-bolt. Download PDF

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Publication number
US1086737A
US1086737A US70995512A US1912709955A US1086737A US 1086737 A US1086737 A US 1086737A US 70995512 A US70995512 A US 70995512A US 1912709955 A US1912709955 A US 1912709955A US 1086737 A US1086737 A US 1086737A
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bolt
sleeve
threaded
stay
sheet
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US70995512A
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Ralph G Taylor
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16BDEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
    • F16B37/00Nuts or like thread-engaging members
    • F16B37/14Cap nuts; Nut caps or bolt caps

Definitions

  • My invention relates to improvements in stay-bolts, and more particularly to flexible stay-bolts commonly employed for staying the walls of locomotive fire-boxes.
  • lt has for its object the maintaining of a steam tight connection between the ends of the bolt and the boiler sheet regardless of the relative shift of the she-ets set up by unequal expansion resulting from the differ-V ence in temperature to which they are subjected.
  • Another object is to so shape the juncture ot' the spherical head and shaft ot the bolt as to prevent ⁇ or at least greatly reduce, the formation of incrustation which oft-en interferes with and at times actually destroys fiexibility of the device.
  • Another object is to provide sectional retaining means capable of separation without damage to, destruction of or displacement of adjacent parts, that will permit of ready acess to the bolt t'or inspection or renewal.
  • a still further object is to reduce to the minimum the size ot the opening in the outer sheet to receive the retaining device and to permit successive renewals of the bolt without the necessity of increasing the dimensions of this opening.
  • Figure l is a side elevation of a flexible stay-bolt, partly in longitudinal section, ap-
  • Fig. 2 is an end view of the headed end of the stay-holt.
  • Fig. 3 is a side view, partly in vertical section, of the cap.
  • Fig. 4 is a top View of the same.
  • Fig. 5 is a side elevation, partly in section, of the removable socket and
  • Fig. 6 is a top view thereof.
  • Fig. 7 is a top view of the supporting sleeve.
  • Fig. 8 is a side elevation, partly in vertical section, of the supporting sleeve.
  • the stay-bolt 5 is a stay-bolt provided at outer end with a spherical head 6 and at its inner end with the threaded portion 7 engaging the threaded opening 4.
  • the juncture of the stay-bolt 5 and its spherical head 6 is so shaped that a well defined edge or shoulder is formed. This shoulder however does not present a flat surface extending at a right angle to the longitudinal axis of the bolt, but is of circular contour struck on an exceedingly short radius.
  • the outer end of the spherical head is provided with the cross grooves or channels 8.
  • Screw threaded into the opening 3 in the outer sheet is the supporting sleeve 9 provided with an internally threaded enlarged portion l0 at its outer end which is expo-sed outside of the boiler shell, the enlargement forming a seat or shoulder l1.
  • the outer periphery of this enlarged and exposed portion is hexagonal as shown at l2 for the application of a wrench.
  • the removable socket 13 Resting firmly on the seat ll, when in proper position, and engaging the threaded portion 10 is the removable socket 13, which is provided on its inner surface, near its inner end, with the circular seat 14C of the same contour as that portion of the spherical head of the stay-bolt with which it engages.
  • socket member 13 At about its center of length socket member 13 is provided with the integral collar 16, the inner face of which, when in proper' position, firmly contacts the outer end of the supporting ⁇ sleeve f) as shown at 17.
  • the outer end of the socket member is externally threaded and is engaged by cap 18, which when screwed to place firmly contacts the outer face of collar 16.
  • the outer periphery of collar 1G is hexagonal for the application of a wrench as shown at 19, as also is the outer periphery of cap 18 as shown at 20.
  • the supporting sleeve 9 is first firmly screwed to place in the outer sheet by applying a wrench to the hexagonal squares 12.
  • Leaky stay-bolts can often be traced to their improper application to the boiler sheet due to the absence of provision, such as means whereby a wrench can be readily applied by which they can be securely and solidly screwed into the sheet. 1n attempting to screw a sleeve into the sheet that is not provided with flat surfaces for the application of a wrench, but is externally threaded over its entire length, as are those most commonly used, they are often crushed or injured to such an extent that if a leak l does not manifest itself at the first test it will develop a.
  • the removable socket 13 is then firmly secured to the end of the supporting sleeve 9 with the machined faces 11 and 17 in solid contact.
  • this member is also provided with flat surfaces for the application of a wrench, this union can be effected in a most substantial manner without injury to the parts.
  • rlhe stay-bolt 5 is then passed through the socket member 13 and supporting sleeve 9 and screwed into the threaded opening in the inner sheet by the application of a suitable tool to the slots or channels 8 in the head ofthe bolt.
  • cap 18 is removed from the removable socket 13 by applying a wrench to the squares 20, holding the socket member from turning by grasping its squared surfaces 19 with another wrench ⁇
  • a suitable tool is then applied to the channel 8 in the head of the bolt and if same is readily moved or turned about it would indicate that it was broken in the shaft portion.
  • a fracture can often be detected by the sound produced on tapping the bolt. If it is found necessary to remove the bolt, the head 21 is cut away from the inside of the iii-e box, the bolt unserewed and replaced by a new one.
  • the inside diameter of the externally threaded portion of sleeve 9 is much larger than the body of the bolt thus permitting the threaded end of the bolt being slightly increased in diameter many times before reaching a size impassible through the sleeve.
  • the only member of the retaining device that would eventually be affected by this continual increase in the size of the bolt is the seat or that portion embracing the head of the bolt. For this reason I have separated this member from the sleeve and detachably secured itl thereto.
  • this removable socket 13 at its inner end is greater than that of the shaft of the bolt and Will thus permit of a limited increase in diameter of its threaded end
  • this seat can be replaced by one of larger internal diameter When necessary and thus entirely remove the necessity of ever removing the sleeve 9 from the outer sheet.
  • the removable socket can be detached Without even disturbing the sleeve in its connection with the sheet.
  • the Walls are thickened, greatly increasing the strength and resistance against spreading and breaking when the strain of the expanding sheets is brought on the bolt. Causing the removable socket 13 to contact the outer end of the sleeve 9 and also the shoulder ll formed by the enlargement of the sleeve, all strains are removed from the thread connection between the socket member and the sleeve when the bolt is in tension.
  • sleeves With integral seats for the bolt head and others with removable seats secured to the inner end of the sleeve, also sleeves With a wrench engaging means outside of the sheet, and sleeves provided With caps or plugs secured to their outer end, but
  • a stay-bolt having a rounded head of a sectional retaining device consisting of a sleeve externally threaded at one end and internally threaded at the other, a threaded closure or cap, an externally threaded member of tubular form, the threaded surface of which is interrupted latitudinally by an integral collar of greater circumference than said threadeda surface, one face of said collar engaging the inner end of said sleeve and the other face engaging said cap, said coupling member having an integral annular seat for en-,n5 gagement with said stay-bolt head.
  • Gope of thin patent may he obtained for five cents each, by addressing the Commsioner of Patente, Washington, D. C.

Description

R. G. TAYLOR.
FLEXIBLE STAY BGLT.
APPLIcATIoN FILED JULY 17, 1912.
1,086,737. e Patented Feb.1o,1914.
COLUMBIA PLANOGRAPH CO..\VASH1NOTDN. D. c.
"@NTE RALPH G. TAYLOR, OF DAVENPORT, IOWA.
FLEXIBLE STAY-BOLT.
Specification of Letters Patent.
Patented Feb. l0, 19ML.
Application filed. July 17', 1912. Serial N0. 709,955.
To ZZ ich om it may concern Be it known that I, RALPH G. TAYLOR, a citizen ot the United States of America, and resident of Davenport, Scott county, Iowa, have invented a certain new and useful Improvement in Flexible Stay-Bolts, of which the following is a specification.
My invention relates to improvements in stay-bolts, and more particularly to flexible stay-bolts commonly employed for staying the walls of locomotive fire-boxes.
It consists essentially7 in a boiler stay-bolt threaded and upset at its inner end in the fire sheet ot' the fire box in the usual manner, and provided at its outer' end with a spherical head properly secured in a flexible manner by my improved means, in the outer sheet of the boiler.
lt has for its object the maintaining of a steam tight connection between the ends of the bolt and the boiler sheet regardless of the relative shift of the she-ets set up by unequal expansion resulting from the differ-V ence in temperature to which they are subjected.
Another object is to so shape the juncture ot' the spherical head and shaft ot the bolt as to prevent` or at least greatly reduce, the formation of incrustation which oft-en interferes with and at times actually destroys fiexibility of the device.
Another object is to provide sectional retaining means capable of separation without damage to, destruction of or displacement of adjacent parts, that will permit of ready acess to the bolt t'or inspection or renewal.
A still further object is to reduce to the minimum the size ot the opening in the outer sheet to receive the retaining device and to permit successive renewals of the bolt without the necessity of increasing the dimensions of this opening.
Further objects are to provide a flexible stay-bolt, simple in construction, durable, efficient in its use, accessible in all its parts, readily set up in operative relation with respect to the sheets of the boiler and inexpensive to manufacture.
These and other objects which will hereinafter more fully appear, I accomplish by mechanism shown in the accompanying drawings in which,
Figure l is a side elevation of a flexible stay-bolt, partly in longitudinal section, ap-
plied to the inner and outer sheets ot the boiler embodying my improvements. Fig. 2 is an end view of the headed end of the stay-holt. Fig. 3 is a side view, partly in vertical section, of the cap. Fig. 4 is a top View of the same. Fig. 5 is a side elevation, partly in section, of the removable socket and Fig. 6 is a top view thereof. Fig. 7 is a top view of the supporting sleeve. Fig. 8 is a side elevation, partly in vertical section, of the supporting sleeve.
ln the drawings, where like reference characters denote corresponding parts throughout the several views, l indicates the outer or boiler shell sheet and 2, the inner or fire sheet. These sheets are provided with the oppositely arranged threaded openings 3 and 4.v
5 is a stay-bolt provided at outer end with a spherical head 6 and at its inner end with the threaded portion 7 engaging the threaded opening 4. For purposes that will hereinafter appear, the juncture of the stay-bolt 5 and its spherical head 6 is so shaped that a well defined edge or shoulder is formed. This shoulder however does not present a flat surface extending at a right angle to the longitudinal axis of the bolt, but is of circular contour struck on an exceedingly short radius. The outer end of the spherical head is provided with the cross grooves or channels 8.
Screw threaded into the opening 3 in the outer sheet is the supporting sleeve 9 provided with an internally threaded enlarged portion l0 at its outer end which is expo-sed outside of the boiler shell, the enlargement forming a seat or shoulder l1. The outer periphery of this enlarged and exposed portion is hexagonal as shown at l2 for the application of a wrench. Resting firmly on the seat ll, when in proper position, and engaging the threaded portion 10 is the removable socket 13, which is provided on its inner surface, near its inner end, with the circular seat 14C of the same contour as that portion of the spherical head of the stay-bolt with which it engages. The walls of the opening in the extreme inner end of the socket member beyond the circular seat are of greater diameter than the bolt and extend parallel thereto as shown at l5. At about its center of length socket member 13 is provided with the integral collar 16, the inner face of which, when in proper' position, firmly contacts the outer end of the supporting` sleeve f) as shown at 17. The outer end of the socket member is externally threaded and is engaged by cap 18, which when screwed to place firmly contacts the outer face of collar 16. The outer periphery of collar 1G is hexagonal for the application of a wrench as shown at 19, as also is the outer periphery of cap 18 as shown at 20.
ln applying my improved stay-bolt to a boiler, the supporting sleeve 9 is first firmly screwed to place in the outer sheet by applying a wrench to the hexagonal squares 12. Leaky stay-bolts can often be traced to their improper application to the boiler sheet due to the absence of provision, such as means whereby a wrench can be readily applied by which they can be securely and solidly screwed into the sheet. 1n attempting to screw a sleeve into the sheet that is not provided with flat surfaces for the application of a wrench, but is externally threaded over its entire length, as are those most commonly used, they are often crushed or injured to such an extent that if a leak l does not manifest itself at the first test it will develop a. defect in a very short time, necessitating its renewal. As is well understood by those familiar with the subject, it becomes necessary to ream out and retap the hole in the sheet whenever a sleeve is renewed, thus continually enlarging the threaded hole, which is very objectionable. @ne of the important features of my improvement is the reducing of the threaded hole to the smallest diameter possible, initially, and to dispense with the necessity of continual enlargement by designing a sleeveY capable of firm, substantial union with the sheet without the slightest injury to itself, and so associated with other parts, as will hereinafter appear, as to permit several renewals of the bolt without the necessity of removing the sleeve. The removable socket 13 is then firmly secured to the end of the supporting sleeve 9 with the machined faces 11 and 17 in solid contact. As this member is also provided with flat surfaces for the application of a wrench, this union can be effected in a most substantial manner without injury to the parts. rlhe stay-bolt 5 is then passed through the socket member 13 and supporting sleeve 9 and screwed into the threaded opening in the inner sheet by the application of a suitable tool to the slots or channels 8 in the head ofthe bolt. lWhen the underside of the staybolt head has closely approached the reiovable socket member or seat 13, the end of the bolt projects through the inner sheet where it is thoroughly riveted or piend over, thus enabling the bolt head to move on the bearing when under pressure as the exigenoies of expansion and contraction demand. The cap 18 is then firmly screwed to the outer threaded portion of the socket member 13 by a wrench applied to the hexagonal squares thereof. The machined face of the inner edge of the cap is set up tightly against the outer machined face of the collar 1G. The parts of the retaining device are thus solidly united, insuring a steam tight joint between the cap and socket meniber and between the socket member and the supporting sleeve.
The merging of the stay-bolt head into the shaft. portion is characterized by a sharply defined rounded shoulder, differing in this respect from others in common use, which usually presenta curved line of the same contour as the head of the bolt but reversely thereof. In the latter case no portion of the seat is vacated or exposed during the movement of the head thereon, while in my device a portion ofthe seat is vacated or exposed as the bolt swings from one side to the other under the influence of the expanding sheets7 with the result that any incrustation forming is cut away or broken up, on the bolt resuming normal position. The formation of incrustation to an ext-ent of rendering the parts practically rigid and immovable is thus automatically guarded against.
iis frequent inspection of stay-bolts and immediate replacement in case of fracture is a mattei' of legislative enactment in many localities, means for easy access and ready renewal are essential. To inspect or test my improved stay-bolt, cap 18 is removed from the removable socket 13 by applying a wrench to the squares 20, holding the socket member from turning by grasping its squared surfaces 19 with another wrench` A suitable tool is then applied to the channel 8 in the head of the bolt and if same is readily moved or turned about it would indicate that it was broken in the shaft portion. A fracture can often be detected by the sound produced on tapping the bolt. If it is found necessary to remove the bolt, the head 21 is cut away from the inside of the iii-e box, the bolt unserewed and replaced by a new one. In order to effect a perfectly tight joint, where the bolt screws int-o the inner sheet, on removing the bolt, it is the usual practice to upset the end, making the threaded portion of slightly larger diameter, and ream out and retap the hole in the sheet, on account of a slight variation in the size of taps.
In most devices it is impossible to renew the bolts wit-h any enlarged threaded portion without also renewing the bushing or sleeve threaded in the outer sheet, by one of larger outside diameter, to enable increasing the inside diameter to accommodate the enlarged threaded end of the bolt. 1n my device several renewals of the bolt can be made Without removing the supporting sleeve and substituting one of larger diameter.
The inside diameter of the externally threaded portion of sleeve 9 is much larger than the body of the bolt thus permitting the threaded end of the bolt being slightly increased in diameter many times before reaching a size impassible through the sleeve. The only member of the retaining device that Would eventually be affected by this continual increase in the size of the bolt is the seat or that portion embracing the head of the bolt. For this reason I have separated this member from the sleeve and detachably secured itl thereto. While the internal diameter of this removable socket 13 at its inner end is greater than that of the shaft of the bolt and Will thus permit of a limited increase in diameter of its threaded end, this seat can be replaced by one of larger internal diameter When necessary and thus entirely remove the necessity of ever removing the sleeve 9 from the outer sheet. As means are provided for grasping the sleeve outside of the sheet by a Wrench, the removable socket can be detached Without even disturbing the sleeve in its connection with the sheet.
ln forming the enlargement to that portion of sleeve 9 exposed outside of the sheet,
the Walls are thickened, greatly increasing the strength and resistance against spreading and breaking when the strain of the expanding sheets is brought on the bolt. Causing the removable socket 13 to contact the outer end of the sleeve 9 and also the shoulder ll formed by the enlargement of the sleeve, all strains are removed from the thread connection between the socket member and the sleeve when the bolt is in tension.
I am aware that prior to my invention sleeves have been made With integral seats for the bolt head and others with removable seats secured to the inner end of the sleeve, also sleeves With a wrench engaging means outside of the sheet, and sleeves provided With caps or plugs secured to their outer end, but
lVhat l claim as new is:
l. The combination With a stay-bolt having a rounded head, of a supporting sleeve having an externally threaded inner end and an enlarged outer end forming a shoulder, of a socket member detachably secured to said sleeve and bearing against its outer end and said shoulder and having an annular seat adapted to engage the rounded head of said bolt, and a cap detachably secured to said socket member.
2. The combination with a stay-bolt having a rounded head, of a sleeve externally threaded at its inner end and provided with Wrench engaging means at its outer end, of a removable socket member engaging the rounded head of said bolt, detachably secured to said sleeve and having an externally exposed portion provided With Wrench engaging surfaces, a closure provided With Wrench engaging means detachably secured to said socket. member. 0
3. The combination with a stay-bolt, of a sectional retaining device consisting of a sleeve externally threaded at one end and internally threaded at the other, an internally threaded cap, a coupling member externally threaded at one end for engagement With the sleeve, and at the other end for engagement With the cap, and having an externally exposed portion provided with Wrench engaging surfaces. 89
4t. The combination With a stay-bolt, of a sectional retaining device consisting of a sleeve externally threaded at one end and internally threaded at t-he other, an internally threaded cap, a coupling member externally threaded at both ends for engagement With the sleeve at one end and the cap at the other, and having an externally exposed portion provided with Wrench engaging means and an internal annular seat for engage- 90 ment With the said stay-bolt.
5. The combination with a stay-bolt, of a sectional retaining device consisting of a sleeve externally threaded at one end and internally threaded at the other, a threaded closure or cap, an externally threaded coupling member of tubular form, the threaded surface of which is interrupted latitudinally by a co-llar of greater diameter than said threaded surface, one face of said collar eno gaging the end of said sleeve, and the other face engaging said cap.
6. The combination with a stay-bolt having a rounded head of a sectional retaining device consisting of a sleeve externally threaded at one end and internally threaded at the other, a threaded closure or cap, an externally threaded member of tubular form, the threaded surface of which is interrupted latitudinally by an integral collar of greater circumference than said threadeda surface, one face of said collar engaging the inner end of said sleeve and the other face engaging said cap, said coupling member having an integral annular seat for en-,n5 gagement with said stay-bolt head.
7. The combination with the inner and outer sheets of a boiler, of an exteriorly threaded supporting sleeve mounted in a threaded opening of the outer sheet and pro- 1w vided with a removably attached socket member located outside of the outer sheet, of a stay-bolt having a rounded head or ball at one end engaging said socket member and threaded at the other end for engagement with said inner sheet.
8. The combination with the inner and outer sheets of a boiler, of a supporting sleeve, mounted in the outer sheet and rovided with a removably attached socket member having Wrench engaging means losurfaces and removable through the outer l0 cated outside of the outer sheet, of e sfayend of said supporting sleeve. bolt engaging the socket member et one end Signed by me at Davenport Iowa this and the inner sheet at the other. 18th day of July 1912.
9. A device of the Class described oom- RALPH G TYLOR prising a boiler sheet, having a supporting sleeve, a staybolt, and e detachable socket VVtnesseS:
member for the Staybolt Within the support- F. W. MILLER, ing sleeve provided with Wrench engaging FRED H. HISE.
Gope of thin patent may he obtained for five cents each, by addressing the Commsioner of Patente, Washington, D. C.
US70995512A 1912-07-17 1912-07-17 Flexible stay-bolt. Expired - Lifetime US1086737A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5253967A (en) * 1991-11-08 1993-10-19 Biach Industries Adapter assembly for tensioning threaded fasteners and method of tensioning threaded fasteners
US20150345533A1 (en) * 2012-06-15 2015-12-03 Oz-Post International, LLC Mounting hardware
US10151337B2 (en) 2013-06-14 2018-12-11 Oz-Post International, LLC Through bolted connection hardware

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5253967A (en) * 1991-11-08 1993-10-19 Biach Industries Adapter assembly for tensioning threaded fasteners and method of tensioning threaded fasteners
US20150345533A1 (en) * 2012-06-15 2015-12-03 Oz-Post International, LLC Mounting hardware
US9771966B2 (en) * 2012-06-15 2017-09-26 Oz-Post International, LLC Mounting hardware
USD798701S1 (en) 2012-06-15 2017-10-03 Oz-Post International, LLC Simulated bolted hardware
US9957998B2 (en) 2012-06-15 2018-05-01 Oz-Post International, LLC Mounting hardware
USD870545S1 (en) 2012-06-15 2019-12-24 Oz-Post International, LLC Threaded connector
US10520007B2 (en) 2012-06-15 2019-12-31 Oz-Post International, LLC Mounting hardware
USD898559S1 (en) 2012-06-15 2020-10-13 Oz-Post International, LLC Decorative structural connector
US11493076B2 (en) 2012-06-15 2022-11-08 The Hillman Group, Inc. Mounting hardware
US10151337B2 (en) 2013-06-14 2018-12-11 Oz-Post International, LLC Through bolted connection hardware
US10907680B2 (en) 2013-06-14 2021-02-02 Oz-Post International, LLC Through bolted connection hardware

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