US3359607A - Releasable catch - Google Patents

Description

J. R. METZ Dec. 26, 1967 RELEASABLE CATCH Filed March 24, 1966 Jose h R Meiz AGENT United States Patent 3,359,607 RELEASABLE CATCH Joseph R. Metz, Ridgeiield, Conn., assignor to N orco, Inc., Ridgefield, Conn, a corporation of Connecticut Filed Mar. 24, 1966, Ser. No. 537,052 11 Claims. (Cl. 24-239 ABSTRACT OF THE DISCLOSURE A heavy duty catch of the snap hook type having a slidable latch releasable by a hammer blow on a longitudinally slidable release member. The latch and release members being interconnected by pin and cam means which provide a mechanical advantage to enable a light blow to release the catch.

This invention relates to releasable clasps or catches, and more particularly to devices of this type which are adapted to accommodate substantially heavy loads or working forces.

Objects of the invention are to provide an improved releasable catch which is relatively easy to release even with heavy loads, and wherein the load force aids in the release after the initial releasing action has taken place; to provide a catch as above, which is especially resistant to vibratory forces in combatting undesirable release; to provide a catch of the type indicated, which is sturdy and failure-resistant while at the same time being of relatively small size and compactly arranged; to provide an improved hook-type catch in accordance with the foregoing, which can be released in response to a relatively light hammer blow on a release member, and also wherein such hammer blow may be directed longitudinally of the mounting shank of the catch body, and at either of opposite sides of the hook formation of the catch; a catch as above, wherein an advantageous mechanical advantage is effected in the release mechanism, enabling release of heavy loads to be accomplished with appreciably lighter applied forces; a catch as indicated, wherein release is opposed by a spring-loaded cam lock, as well as by an additional spring, giving assurance against accidental release dueto shock, vibration and the like; and a catch which is relatively simple, having few, functionally simple components in a mechanically sound or valid assemblage, and which is of relatively low cost.

Other features and advantages will hereinafter appear.

In the drawings:

FIG. 1 is a longitudinal sectional view of a heavy-duty vibration-proof catch as provided by the invention, a portion of the jaw or hook formation being shown in elevation.

FIG. 2 is a top plan view of the catch of FIG. 1.

FIG. 3 is a fragmentary side elevational view of the catch, showing exterior details not seen in FIG. 1.

FIG. 4 is a side elevational view of a locking bar as provided in the catch.

FIG. 5 is a top plan view of the locking bar of FIG. 4.

FIG. 6 is an end elevational view of the locking bar of FIGS. 4 and 5.

FIG. 7 is a side elevational view of a release bar as provided in the catch of FIG. 1.

FIG. 8 is a top plan view of the release bar of FIG. '7.

FIG. 9 is an end elevational View of the release bar of FIGS. 7 and 8.

FIG. 10 is a front elevational view of an impact member of the catch of FIG. 1. I

FIG. 11 is a side elevational view of the impact member of FIG. 10.

Considering first FIGS. 1-3, the catch comprises a body member 29 provided with a hook formation 22 which'has Patented Dec. 26, 1967 at its lower portion a gap 24 adapted to receive a cooperable member in the form of a heavy clevis pin 26. The body 20, including the hook formation 22, is of flat shape as seen in FIG. 2, having opposite sides 28, and further including a shank 32 having a large-diameter portion 34 and a small-diameter portion 36.

In the body 20 there is provided a first guide channel 38 which opens into the gap 24 of the hook formation and extends upwardly and to the right therefrom as viewed in FIG. 1 so as to be angularly disposed with respect to the axis AA of the shank. The axis of the first guide channel 38 makes an angle, indicated at X in FIG. 1, which is roughly on the order of 35 with respect to the axis A--A of the shank.

Carried in the first guide channel 38 is a locking bar 40 shown in detail in FIGS. 4, 5 and 6. The locking bar 40 has a nose portion 42 provided with a rounded bottom surface 44, a rounded tip 45 and a concave upper surface 46 which latter is arranged to generally nest the cooperable member or pin 26 as seen in FIG. 1.

A helical compression spring 48 is disposed in the upper portion of the first guide channel 38 and engages the upper end of the locking bar 40 and also a closure plug 50 which latter is affixed in the guide channel by a cross pin 51. Thus, the locking bar 40 is continually biased to its advanced, downward position as illustrated in FIG. l, where in it retains and locks in place the cooperable member 26, holding the latter securely in the gap 24 of the hook formation 22.

In accordance with the present invention, the improved catch is especially resistant to release accidentally in response to shocks, vibration and the like, yet may be easily released with relatively little force in spite of heavy reactive forces being experienced by the locking bar 40 due to heavy loads on the cooperable member 26. The member 26 may be part of a structural formation (not shown) to which the hook 20 is to be releasably secured, and in turn to which any other structure attached to the shank 36 of the catch is to be releasably secured.

In accomplishing a quick and easy release of the member 26 in spite of heavy loads suffered thereby while at the same time resisting accidental release of the member, there is provided by the invention a novel release mecha nism which is cooperable with the locking bar 40 through a cam connection, said release mechanism including a second biasing or spring means, which acts on the cam connection.

Referring to FIG. 1, the body 20 of the catch is provided with a second guide channel 52 which is shown as extending through the shank portions 34 and 36 of the body. In the second guide channel 52 there is a release bar 54 (see also FIGS. 7, 8 and 9) having a cam slot 56, a front cam portion 58, and a back cam portion 60. The release bar 54 has a cylindrical body portion 62, whereas the cam portions 58, 60 comprise a relatively thin front extension designated generally by the numeral 64.

To accommodate the cam extension 64 of the release bar, the locking bar 40 has a longitudinal slot 66 arranged to slidably receive said extension, In the slot 66 there is a fixed cross pin 68 which is adapted to be received in the cam slot 56 of the release bar 54, and to be acted on by the cam portions 58, 60' of said bar.

The release bar 54 is continually urged or biased forwardly or to the left by a helical compression spring 70 disposed in the second guide channel 52 and engaging the back end of the release bar as well as an abutment 72 carried by the shank portion 36.

For the purpose of actuating the release bar or cam lock 54, an operator is provided, comprising an irnpace member 74 in the form of an annulus which is longitudinally slidable on the shank portion 34 of the body 20'. The said shank portion is provided with diametric slots 76, in which there is disposed a cross pin 78 passing through the release bar 40 and also the annulus 74 and constituting a connecting means between said bar and annulus. The impact member or annulus 74 has impactresistant formations or lugs 80 adapted to receive a hammer blow, by which a forcible retraction or left-to-right movement of the release bar 54 may be effected.

The operation of the catch is as follows: Referring to FIG. 1, the parts are shown in the locking position, with the cooperable member 26 forcibly retained in the hook formation 22 of the catch body 20. It will be noted that the cam portion 60 of the release bar is in engagement with the follower pin 68 of the locking bar 40, and is held in such engagement under continual force as exerted by the helical compression spring 70. The locking bar 40 is thus securely retained in its advanced, locking position, being held therein not only by such cam engagement but also by the locking-bar spring 48, and by frictional forces.

By virtue of the two springs 48, 70 both tending to retain the locking bar 40 in the advanced position, and by virtue of the cam engagement between the cam portion 60 of the release bar and the follower pin 68 of the locking bar there is virtually no possibility for the catch to be accidentally released, even though considerable forces are experienced and considerable loads are carried by the cooperable member 26 and hook formation 22.

When it is desired to release the member 26 from the hook formation, it is only necessary to strike the impact member 74, as by a hammer blow, on either of the lugs 80 thereof. This will effect a retraction of the release bar 54 against the action of the spring 70, and the cam portion 58 now comes into play, engaging the follower pin 68 and forcibly retracting the locking bar 40 against the action of the spring 48. By virtue of the rounded configuration of the cooperable member or pin 26, the initial retracting movement of the locking bar 40 will be supplemented by an additional retracting force due to the camming effect of said rounded surface of the pin 26 against the rounded nose portion 42 of the locking bar.

The releasing movement of the cooperable member or pin 26 will be downward, along an axis or direction indicated at BB, such axis making an angle of roughly 90 with the axis AA of the shank 32 of the catch. In aiding the retraction of the locking bar 40, the pin 26 will shift along a guiding edge 84 of the hook formation, as seen in FIG. 1.

I have found that with the above construction a numberof advantages are had, in a heavy-duty catch. For in stance, the arrangement of the guide channels and the locking and release bars enables a relatively shallow mouth to be provided on the hook formation 22. Once the initial releasing movement of the locking bar 40 is efiected, the load forces experienced by the pin 26 and the rounded shape of such pin will tend to insure a complete release of the pin by a cam action which effects a full retraction of the locking bar. However, prior to any initial releasing movement, the locking bar 40 will be securely held in its advanced position due to its spring 48 and also the cam connection with the release bar 54 which is under the action of the advancing spring 70. Upon the impact member 74 suffering a hammer blow, the release bar 54 can effect a retraction of the locking bar with relatively small force, due to the camming action provided by the cam portion 58, which represents .a mechanical advantage. Such mechanical advantage results since the release bar 54 has much greater movement than the locking bar 40. The same mechanical advantage also exists when the releasebar 54 is maintaining the locking bar 40' in the advanced position, due to the cam portion 60 as will be understood. v

Thecatch as above described is sturdy and failure-resistant, while at the same time being of relatively small size and compactly arranged. The direction of the ham mer blow islongitudinally of the mounting shank 32 of the catch body and may be applied at either of opposite sides of the hook formation of the body. The catch is relatively simple and has few, functionally simple components in a mechanically sound or valid assemblage, and is of relatively low cost. Accidental release of the catch is positively prevented by the multiple springs and the cam lock connection comprising the release bar 54 acting on the locking bar 40.

Variations and modifications may be made within the scope of the claims, and portions of the improvement may be used without others.

I claim:

1. A heavy duty releasable catch comprising, in combination:

(a) a body having a hook formation including a downwardly open gap, a first guide channel which opens into a gap of the hook, and a second guide channel communicating with said first guide channel,

(b) a locking bar movable longitudinally in said first guide channel between an advanced position enabling one end thereof to protrude into said hook gap to lock a cooperable member received therein and a retracted position wherein the end is withdrawn from the gap for freeing said member,

(c) yieldable means urging said locking bar to advanced position,

(d) a release bar slidable in said second guide channel between extended and retracted positions,

(e) an operable member slidably carried by said hook body on the exterior thereof, said operable member having means engageable with a force-applying instrumentality to effect its movement,

(f) means connecting said operable member and said locking bar for simultaneous movement,

(g) cooperable means connected with said bars, effecting a retraction of the locking bar in response to retracting movement of the release bar in a direction away from said first guide channel, and

(11) means biasing said release bar to extended position.

2. A heavy duty releasable catch as in claim 1, wherein:

a) the gap of the hook formation has an inner guiding edge at one side, which engages, and determines the direction of removal of, the cooperable member,

(b) said first guide channel extending angularly upward from the gap of the hook and having an axis making an angle between and 180 with the guided direction of removal of the said cooperable member.

3. A heavy duty releasable catch as in claim 2,

wherein:

(a) the angle between the axis of the first channel and the direction of removal of the cooperable member is roughly 4. A heavy duty releasable catch as in claim 2, wherein:

(a) the axis of the said second guide channel is substantially at right angles to the direction of removal of the said cooperable member.

5. A heavy duty releasable catch as in claim 2, wherein:

(a) the locking bar has a nose portion provided with a rounded edge for engagement with a rounded surface of said cooperable member.

' 6. A heavy duty releasable catch as in claim 5, where- 1n:

(:1) the nose portion of the locking bar is of tapered cross section,

(b) said nose portion having an upper concave surface adapted generally to nest the cooperable member and having a rounded bottom surface engageable by the cooperable member when entering said gap, to momentarily cam the locking bar to retracted position.

7. A heavy duty releasable catch as in claim 1, where- (a) the said operable member has impact-resistant portions adapted to be struck by a hammer.

s. A heavy duty releasable catch as in claim 7, where- (a) the operable member comprises an annulus slidable on the said shank,

(b) said impact-resistant portions comprising a pair of lugs disposed on opposite sides of, and projecting from, said annulus.

9. A heavy duty releasable catch as in claim 1, where- (a) cooperable means are provided on said bars, maintaining the locking bar in extended, locking position when the release bar is maintained extended.

10. A heavy duty releasable catch as in claim 9, where (a) the two said cooperable means on the locking and release bars comprise cam and cam follower devices respectively on said bars, providing a mechanical ad- 6 vantage wherein the release bar has a greater movement than the locking bar.

11. A heavy duty releasable catch as in claim 1, where- (a) the cooperable means on the locking and release bars comprise a cam and cam follower respectively on said bars, providing a mechanical advantage wherein the release bar has the greater movement.

References Cited UNITED STATES PATENTS 761,859 6/ 1904 Sweet. 1,051,428 1/1913 MoLeran 24-239 XR 1,062,653 5/ 191-3 Koons. 1,198,139 9/1916 Lyon. 1,228,513 6/ 1917 Anderson.

DONALD A. GRIFFIN, Primary Examiner.

Claims (1)

1. A HEAVY DUTY RELEASABLE CATCH COMPRISING, IN COMBINATION: (A) A BODY HAVING A HOOK FORMATION INCLUDING A DOWNWARDLY OPEN GAP, A FIRST GUIDE CHANNEL WHICH OPENS INTO A GAP OF THE HOOK, AND A SECOND GUIDE CHANNEL COMMUNICATING WITH SAID FIRST GUIDE CHANNEL, (B) A LOCKING BAR MOVABLE LONGITUDINALLY IN SAID FIRST GUIDE CHANNEL BETWEEN AN ADVANCED POSITION ENABLING ONE END THEREOF TO PROTRUDE INTO SAID HOOK GAP TO LOCK A COOPERABLE MEMBER RECEIVED THEREIN AND A RETRACTED POSITION WHEREIN THE END IS WITHDRAWN FROM THE GAP FOR FREEING SAID MEMBER, (C) YIELDABLE MEANS URGING SAID LOCKING BAR TO ADVANCED POSITION, (D) A RELEASE BAR SLIDABLE IN SAID SECOND GUIDE CHANNEL BETWEEN EXTENDED AND RETRACTED POSITION,

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