GB1561228A

GB1561228A - Blind nut with a resilient split tapere cage

Info

Publication number: GB1561228A
Application number: GB682877A
Authority: GB
Original assignee: CEM CO Inc
Current assignee: CEM CO Inc
Priority date: 1976-06-01
Filing date: 1977-02-18
Publication date: 1980-02-13
Also published as: FR2353745B1; DE2657222B2; ES224954Y; DE2657222C3; IT1077515B; DE2657222A1; CA1100796A; ES224954U; FR2353745A1

Description

(54) A BLIND NUT WITH A RESILIENT SPLIT TAPERED CAGE ERRATUM SPECIFICATION NO 1561228 Page 3, line 2, after drawings. Start New Pamgraph insert Reference has been directed in pursuance of section 9 subsection (1) of the Patents Act 1949 to patent No. 1073472 THE PATENT OFFICE 25March 1980 Bas 75632/9 ------------- It is one aim of the present invention to provide a simplified and efficient form of blind nut of the kind referred to.

It is another aim of the present invention to provide a blind nut having a resiliently tapered cage the periphery of which has provided therein four slots to permit a more concentric radial expansion which is achieved upon moving the nut member along the screw threaded member to distort the resiliently tapered cage.

It is still another aim of the present invention to provide a blind nut with resiliently split tapered cage wherein the latter has an inwardly extending flange or shoulder at the upper end of the cage, in order to prevent the threaded nut from being pulled through the tapered cage, which removes an essential drawback found in known designs of such blind nuts.

It is yet another aim of the present invention to provide a blind nut with resiliently split tapered cage and having in particular four slots which offer a more concentric radial expansion and the inwardly extending flange or shoulder at the upper end of the cage, which prevents the threaded nut from being pulled through. periphery of said cage member extending from the upper end part way to the lower end thereof, an inwardly extending shoulder formed at the upper end of the axial cylindrical bore of said cage member, a tapered portion the maximum diametrical extent of which is greater than the diameter of said hole formed on the outer periphery of said cage member under said outwardly extending flange to frictionally hold said cage member in position in said circular hole in said parent member at which time said tapered portion is reduced in diametrical extent with the closing up of said slots to reduce the diameter of said bore of said cage member adjacent the upper end thereof in position in said parent member, and a screw threaded nut frictionally held in position in said bore of the cage member said screw threaded nut in use, being advanced along a fastening screw when threaded through said threaded nut, causing said cage member to be distorted by engagement of the nut with said reduced portion of the bore and to form a ridge around the underside of the said hole in said parent member in which it is positioned so as to prevent its withdrawal therefrom.

(54) A BLIND NUT WITH A RESILIENT SPLIT TAPERED CAGE (71) We, C. E. M. COMPANY, INC. a corporation organized and existing under the laws of the State of Connecticut, United States of America, of 24 School Street, Danielson, State of Connecticut, United States of America, (assignee of GUENTER WEXLER) do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and bv the following statement: The present invention relates to blind nuts of the kind wherein a cage member has located therein a nut member which is adapted to be axially moved along a screw threaded member to distort the cage member to secure it in a parent member.

It is one aim of the present invention to provide a simplified and efficient form of blind nut of the kind referred to.

It is yet another aim of the present invention to provide a blind nut with resiliently split tapered cage and having in particular four slots which offer a more concentric radial expansion and the inwardly extending flange or shoulder at the upper end of the cage, which prevents the threaded nut from being pulled through.

It is still a further aim of the present invention to provide a blind nut with resiliently split tapered cage wherein the range of torques required to seat the threaded nut and to distort the cage for securely holding the threaded nut in position is 30 to 55 in.

Ibs. instead of 13 to 15 in. Ibs. in known designs.

According to the present invention there is provided a blind nut, embodying cyclindrical resilient cage member having an axial cvclindrical bore and an outwardly extend ing flange at the upper end thereof for preventing the passage of said cage member through a circular hole in a parent member, in which it is adapted to be in use inserted, at least four V-shaped slots formed in the periphery of said cage member extending from the upper end part way to the lower end thereof, an inwardly extending shoulder formed at the upper end of the axial cylindrical bore of said cage member, a tapered portion the maximum diametrical extent of which is greater than the diameter of said hole formed on the outer periphery of said cage member under said outwardly extending flange to frictionally hold said cage member in position in said circular hole in said parent member at which time said tapered portion is reduced in diametrical extent with the closing up of said slots to reduce the diameter of said bore of said cage member adjacent the upper end thereof in position in said parent member, and a screw threaded nut frictionally held in position in said bore of the cage member said screw threaded nut in use, being advanced along a fastening screw when threaded through said threaded nut, causing said cage member to be distorted by engagement of the nut with said reduced portion of the bore and to form a ridge around the underside of the said hole in said parent member in which it is positioned so as to prevent its withdrawal therefrom.

The present invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1. is a vertical axial section of a blind nut according to the present invention: Figure 2. is a top plan view of the blind nut shown in the state of Figure 1: Figure 3. is a vertical axial section similar to that shown in Figure 1, with the blind nut in a parent member in which it is to be located; Figure 4. is a top plan view of the blind nut shown in the state of Figure 3; and Figure 5. is a vertical axial section similar to those shown in Figures 1 and 3 with a second parent member in position and the blind nut secured to. the two parent members.

Referring now to be drawings and in particular to the embodiment of the blind nut shown in the accompanying drawings, the nut is provided with a cage 1. one end of which is provided with an outwardly extending flange 2 and a cylindrical axial bore 3.

The wall of the cage member is provided with four axially disposed V-shaped slots 4.

Mounted in the bore 3 of the cage 1 is a cylindrical nut 5, the periphery of which may be knurled, in known manner, to increase the friction between the bore 3 of the cage 1 and the nut 5, which is held by friction in the bore 3.

The upper edge of the nut 5 has preferably a chamfer 6, to facilitate its movement along the bore 3 as more particularly explained below.

The cvlindrical axial bore 3 extends to the lower end of the cage, so that the nut 5 can be inserted into the bore 3 from the lower end of the cage 1.

The outer wall of the cage 1 is formed with a taper 7 extending from under the flange 2 to approximately the level of the uppermost surface of the cylindrical nut 5, when the latter is located in the lower end of the bore 3 of the cage 1. An inwardlv extended shoulder or stop 8 formed at the upper end of the bore 3 prevents the nut 5 passing inadvertently out of the cage 1 in an upwards direction.

In use one parent member 9 has formed therein a hole 10 which is equivalent to a size to take the lower end of the cage 1, in which a cylindrical nut 5 is secured by friction. The cage 1 is then pressed home into the hole 10 which causes the taper 7 of the cage 1 to close in and reduce the bore 3 of the cage 1, which is possible owing to the four V-shaped slots formed therein. The cage 1 and the nut 5 are thus securely held in position, ready for assembly.

The second parent member 11 is then placed in position and a fastening screw or a threaded bolt 12 is screwed into the nut 5.

When the head of the threaded bolt 12 abuts the second parent member 11, rotation of the bolt causes the nut 5 to travel along the threaded bolt 12 and to thus distort the cage 1. The shoulder or stop 8 prevents the nut 5 from being pulled through the cage 1. A ridge 13 is formed around the underside of the hole 10 of the first parent member 9 preventing the withdrawal of the cage 1. At the same time. the second parent member 11 is secured in position.

Claims

WHAT WE CLAIM IS: 1. A blind nut, embodying a cylindrical resilient cage member having an axial cylindrical bore and an outwardlv extending flange at the upper end thereof for preventing the passage of said cage member through a circular hole in a parent member, in which it is adapted to be in use inserted. at least four V-shaped slots formed in the periphery of said cage member extending from the upper end part way to the lower end thereof, an inwardly extending shoulder formed at the upper end of the axial cylindrical bore of said cage member, a tapered portion the maximum diametral extent of which is greater than the diameter of said hole, formed on the outer periphery of said cage member under said outwardly extending flange to frictionally hold said cage member in position in said circular hole in said parent member at which time said tapered portion is reduced in diametral extent with the closing up of said slots to reduce the diameter of said bore of said cage member adjacent the upper end thereof and a screw threaded nut frictionally held in position in said bore of the cage member said screw threaded nut, in use, being advanced along a fastening screw when threaded through said threaded nut, causing said cage member to be distorted by engagement of the nut with said reduced portion of the bore and to form a ridge around the underside of the said hole in said parent member in which it is positioned so as to prevent its withdrawal therefrom.
2. A blind nut as claimed in claim 1 in which the screw threaded nut is cylindrical.
3. A blind nut as claimed in claim 1 or claim 2. in which the periphery of the screw threaded nut is knurled.
4. A blind nut as claimed in claim 1, 2 or 3 in which the upper end of the screw threaded nut has a chamfered edge.
5. A blind nut as claimed in anv one of the preceding claims, in which the axial bore extends right through the cage.
6. A blind nut constructed and arranged substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 4 of the accompanying drawings.
7. A blind nut and screw combination constructed and arranged substantially as hereinbefore described with reference to and as illustrated in Figure 5 of the accompanying drawings.