Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3600760 A
Publication typeGrant
Publication dateAug 24, 1971
Filing dateDec 11, 1969
Priority dateDec 11, 1969
Publication numberUS 3600760 A, US 3600760A, US-A-3600760, US3600760 A, US3600760A
InventorsEshleman Ralph G
Original AssigneeHamilton Watch Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Release mechanism
US 3600760 A
Images(3)
Previous page
Next page
Description  (OCR text may contain errors)

0 United States Patent [111 00,7

[72] Inventor Ralph G. Eshleman 2,845,676 8/1958 Huber 24/201 D Lancaster, Pa. 3,425,739 2/1969 Frost et a1 24/201 D X 969 Primary Examiner-Donald A. Griffin Attorney-Le Blanc and Shur [45 Patented Aug. 24, 1971 [73 l Assignee Hamilton Watch Company Lancaster, Pa.

ABSTRACT: This invention relates to a time-delay release 5 RELEASE MECHANISM mechanism for restraining and releasing large loads. For excm 6 Drawing Fm ample, as In the case of a steel banding strap used to hold a large package together. The invention, in one embodunent, um [52] US. Cl. 24/68 R, eludes adjacent rotatably mounted release levers which 24/201 58/59 distally engage the ends of the strap at the mounting thereof. [5] I III!- Cl. ..A43C 11/14, The release levers are connected by a rotatably mounted G041 33/00 locking lever. ln a second embodiment, a single release lever, {50! Fit 0 Search 58/59, 80; adapted to engage one end of a fixed strap is ili l av 24/68 CD68 SR'68 tached to a rotatable mounting by a locking lever. A timer selectively allows rotational movement of the locking lever to 1 References CM free, in one embodiment both release levers, and in the other, UNITED STATES PATENTS the release lever and the mounting, which in turn release the 2,497,467 2/1950 Peters 24/68 CT .oad.

Patented Aug. 24, 1971 0 s Sheets-Sheet 1 INVENTOR RALPH G. ESHLEMAN ATTORNEYS Patented 1971 3 Sheets-Sheet 2 FIG. 4

INVENTOR RALPH G. ESHLEMAN ATTORNEYS Patented Aug. 24, 1971 3 Sheets-Sheet 5 INVENTOR G ESHLEMAN ATTORNEYS RELEASE MECHANISM This invention specifically pertains to time-delay release mechanisms, whereby a load is contained until a preset time elapses, and then, is released.

The prior art contains a variety of mechanisms including timers which unlock release levers. Of note is US. Pat. No. 2,534,836 to R.I. I-Iakomaki. In the I-Iakomaki device, a cam on the timer displaces a catch which in turn releases a hook which rotates to disengage the load carried by the hook. The hook is used to release a high-altitude balloon, and is not adapted to the particular problem of releasing package banding straps.

Prior art release mechanisms, including the Hakomaki device, have the distinct disadvantage of requiring a timer output large enough to overcome a load acting through the release lever, on the locking mechanism. For example, Hakomaki attempts to minimize the output required from the timer by using overlapping rather than hooking-type locking levers. However, a positive displacement of the locking member by the timer to release the load is still required.

The release mechanism of this invention is designed to hold the two ends of a packaging strap. The ends of the strap engage abutting release levers which are held until a preset time elapses. The mechanism of this invention uses the incident load to release a locking lever, as compared to the conventional means of using a timer output to drive the said lever thereby releasing the load.

In the alternate situation wherein one end of the strap is fixed, one of the release levers is replaced with a rotatable latch which is locked in an abutting relationship to the free end of a single release lever.

Accordingly, it is an object of this invention to provide a timed release mechanism for holding the ends of the banding strap.

g It is another object to provide a simple and accurate release mechanism having a timer for simultaneously releasing the ends of a packaging band.

It is a further object .to provide an elongated, pivotally mounted release lever adapted to transfer a negligible torque to the locking lever, thereby eliminating the possibility of stalling the timer under the load necessary to release the locking lever.

It is a further object to provide a release mechanism wherein the load to be released normally urges the locking lever into the unlocked position.

It is yet another object to provide a locking lever for a timedelay release mechanism wherein the load to be released normally urges a tab on the said lever into a slot on the rotating output shaft of the timer to displace the lever, and release the load.

It is still another object to provide a release lever pivotally mounted at an end thereof and adapted to engage a load at the pivotal mounting thereby transferring a nearly negligible torque from the load to the lever.

These and other objects will become apparent with relation to the following drawings and description:

FIG. 1 is a front elevation in partial section of the first embodiment of this invention in a locked position;

FIG. 2 is a front elevation also partially in section of the embodiment of FIG. 1 showing the release position in phantom;

FIG. 3 is a front elevation partially in section of the second embodiment of this invention;

FIG. 4 is an elevational view in partial section of the timing mechanism;

FIG. 5 is a perspective view of the embodiment of FIG. 1 and the timer with the output shaft withdrawn from the timing mechanism; and I FIG. 6 is a perspective view of the timer gear train.

With attention to'FlG. l, the first embodiment of this invention features right and left release levers 23 and 13, respectively. These levers are substantially Is-shaped, and, the particular advantages of this invention stem, in part, from their design.

Left release lever 13 is rotatably mounted on a base (not shown) at pin 15. Pin 15 engages the upper portion of a vertical leg 17 on a nearly horizontal line with the load-engaging hook 19, on leg 17. Thus, the main force of the load from the strap 21 is carried by pin 15 while lever 13 carries a nearly negligible counterclockwise moment imparted by the load.

Right release lever 23 is rotatably mounted at the base at pin 25. The vertical leg 27 of lever 23 similarly engages a load at hook 29. The load from strap 31 is imparted to lever 23 on nearly a horizontal line with pin 25.

The horizontal legs 33 and 35 of levers 13 and 23, respectively, are adapted to nest as shown in FIG. 1 touching only at pivot point 37. In order to minimize the torque from lever 13 transmitted to lever 23 the rounded end 39 of leg 33 is designed so that a line normal to end 39 at the pivot point 37 will extend through the pin 25 of lever 23.

Locking lever 41 rotatably mounted on the base at pin 43 exerts a hooking action on locking pin 45 of lever 23. When hooking portion 47 of lever 41 is engaging lever 23 as shown in FIG. 1, pin 45 is designed to be in vertical alignment with the mounting pin 43.

It should be noted that the horizontal load applied in FIG. 1 to lever 23 exerts a torque in a clockwise direction on lever 23 which is transmitted through locking 45 to locking lever 41. The load from the lever 13 is dissipated at pin 25, and therefore, the force exerted on locking lever 41, the clockwise torque, tends to urge rotation of the locking lever 41 in a clockwise direction about its mounting.

With attention to FIGS. 1 and 2, timer output shaft 51, having slot 53, acts as a stop for the clockwise rotation of locking lever 41. Key 55 normally rides on the shaft 51 as it rotates until slot 53 registers on the key, at which point, key 55 is urged into the slot by the clockwise torque from release lever 23.

As shown in FIG. 2, movement of the key 55 into the slot 53 unlocks lever 41 and frees lever 23 for rotation about pin 25 and lever 13 for rotation about pin 15, thereby releasing straps 21 and 31.

A primary purpose of this invention has been to develop a timed release mechanism wherein the unlocking load requirement will not stall the timer. As shown in the above description the design of the release levers dissipates nearly all of the load exerted on the levers at their respective mountings. This particular design allows the release of extremely large loads with a very small timing mechanism.

In testing the mechanism of FIG. 1, a load of 1,125 pounds was applied at strap 21 and a zero load at strap 31. The locking lever was then removed so that the left release lever 13 was restrained only by the right lever 23. The result was that the left lever exerted insufficient torque on the right lever to force the right lever into rotation, allowing the left lever to release the load. This would indicate that the load on the left release lever is limited primarily by the integrity of the support and not by the timer output device.

Moreover, when both release levers are loaded, a constant force is exerted on the timer output shaft urging key 55 into slot 53. The timer output is not subject to a surge requirement to release the load. In eliminating a surge requirement the possibility of a stall at release is also eliminated. If stalling is to occur, the timer will stall when it is started, due to the force exerted by key 55 on timer output shaft 51. However, as pointed out, the device of this invention minimizes the load carried by the timer output shaft and maximizes the load carried by the release lever mounting pins and support.

FIG. 3 illustrates a second embodiment wherein the right release lever is replaced by a nonload-carrying latch member. Load straps 61 and 63 engage, respectivelythe left release lever 65 and a support post 67. The left release lever is rotatably mounted by pin 69 to support (not shown).

The right release latch 71 is similar in design to the lever of the first embodiment. However, even though the members 71 and 65 touch at a pivot point 73 and the force line which is normal to the rounded end 75 of the left lever 65 passes through mounting pin 77 for lever 71, spring 79 is necessary to rotate right member 71 clockwise, permitting counterclockwise rotation of left lever 65.

The locking lever, including its key, hook, and the rotatable mounting therefor, together with the timer-output shaft and hook-engaging pin are identical with those disclosed for the first embodiment. Accordingly, these members are identified by the same reference numbers used in FIGS. 1 and 2.

A minimal load is transmitted from the left lever 65 to mounting pin 77. The spring 79 is disposed to normally urge locking lever 41 in a clockwise direction, and key 55 into slot 53 as the timer output shaft 51 rotates.

The timer used in the release mechanism of this invention may be of any conventional design incorporating a rotatable output shaft. The preferred embodiment shown in FIGS. and 6 is a conventional artillery fuse clock timer having an additional actuating plunger 81 and a transportation locking pin 83 which locks the plunger 81 by passing through groove 85 to engage hole 87.

- Timing mechanism 89 includes a conventional escapement spring 92 and lever 93 which carry pallets 91 which engages the escape wheel 95 as shown generally in FIGS. 4 and 6. The start-stop lever 97 is pivotally mounted in mechanism 89 and biased by return spring 99. Lever 97 carries a spring 101 with a hook formed on the end which engages escape lever 93 and causes a pallet 91 to engage the teeth of escape wheel 95, causing the timer gear train 96 to stop.

The timer of FIGS. 5 and 6 is driven by mainspring 103 which is wound by rotation of knob 105. Knob 105, mainspring 103, and gear 107 are rigidly attached to timer output shaft 51. Gear 107 meshes with the gear train 96 of timing mechanism 89 as shown in FIG. 6.

To stop the timer of FIGS. 4 and 5, plunger 81 is depressed against spring 111 rotating lever 97 against return spring 99 and thereby locking lever 93 and pallet 91 in escape wheel 95. Key 83 is then inserted through hole 87 to lock the timer.

To use the timer knob 105 is rotated clockwise as shown in FIG. 6'until the desired time, as indicated on the dial 110 carried by knob 105 lies beyond arrow 113. The timer is allowed to run until the desired time delay is aligned with arrow 113. Rotation of the knob 105 to set the timer also winds mainspring 103. v

Setting. clutch 114 allows gear train 96 to rachet during setting through elongated pivot hole 1 16 in back plate 1 18 and restraining spring 120 mounted on plate 122. The action of the spring 120 against shaft 124 as shown in FIG. 6 permits setting of the timer without driving the gear train 96 backward.

Plunger 81 is then depressed and key 83 is inserted to lock the timer. Removal of key 83 will then start the timer which will rotate output shaft 51 under control of the escapement until slot 53 registers on key 55 at which point the release levers 13 and 23 will release the load as shown in FIG. 2.

In summary, this invention provides an accurate and dependable time delay release mechanism adapted to release large loads without stalling. Two embodiments are disclosed, the first utilizing two release levers each engaging a load, and in a second, a single, loaded release lever.

A mechanical timer has also been described which is adapted to drive a slotted output shaft. Many well-known timers, both mechanical and electrical, can be adapted to drive the said shaft in the manner disclosed provided they have a start-stop capability. The release mechanism of this invention will function even though the timer used has a very weak output because there is no surge requirement for releasing the load at the expiration of the preset time. Accordingly, this invention is not limited to the particular timer disclosed, but comprehends any conventional timer which may be adapted to this invention utilizing principals well known in the art.

It is further disclosed that the invention is used to release large loads held by steel banding straps. However, the release mechanism of this invention is not intended to be limited to releasing straps. This invention is intended to be used with any type of load which can be applied to the release lever or levers in the manner herein described.

It will be obvious to those skilled in the art that a variety of design modifications are possible within the scope of this invention. The release mechanisms herein disclosed are preferred embodiments of this invention and the description thereof not intended to exclude obvious design modifications.

What is desired to be secured by US. Letters Patent is claimed as follows:

1. A settable time-delay release mechanism for restraining and releasing extremely large loads comprising:

a. A first release lever rotatably connected to a support at an end thereof, said first lever including a load-engaging portion at an end adjacent the mounting and a pivot at an end opposite the connection;

. A second release lever disposed adjacent said first lever, and rotatably connected to a support at an end thereof, said second lever having a load-engaging portion at an end thereof adjacent said connection, a pivot portion for engaging the pivot portion of said first lever, and a lockengaging portion;

. Time-delay locking means for engaging the locking portion of said second lever when the pivot portion of said second lever engages the pivot portion of said first lever, and for subsequently releasing said lever; so that when said first lever engages a load and said second lever engages a load said locking means holds said levers in adjacent disposition at the pivot portions thereof for a preset time, and then releases said levers for rotation, releasing the said loads.

2. The release mechanism of claim 1 wherein said first lever includes a load-engaging hook disposed at the rotatable support connection and an elongated lever arm having, distally thereto, a rounded pivot portion; so that when said lever engages a load, said load normally urges rotation of said lever to release said load; and when the pivot portion of said first lever engages the pivot portion of said second lever, said second lever prevents rotation of said first lever.

3. The release mechanism of claim 2, wherein said second release lever includes a load-engaging hook disposed at the rotatable support connection; a pivot portion disposed adjacent the rotatable support connection for engaging the pivot portion of said first lever; and an elongated lever arm terminating in a lock-engaging portion, so that when said hook engages a load, said load normally urges said lever into rotation about the support connection to release said load, and when said locking means engages the locking portion of said lever arrn said locking means prevents rotation of said release lever.

4. The release mechanism of claim 3 wherein said timedelay locking means comprises:

a. A locking member rotatably connected to a support at an end thereof and carrying a lever-engaging hook at an end opposite the rotatable support connection; so that when said second release lever engages a load, and said member engages said release lever, said lever normally urges said member into rotation about said support connection to disengage the hook and said release lever;

. Timer means disposed adjacent said locking member for preventing rotation of said locking member for a preset time and for allowing rotation of said locking member to release said second lever so that when said timer allows rotation of said locking member the hook releases said second lever for rotation and said second lever releases said first lever for rotation, said levers releasing the loads.

5. Time-delay locking means of claim 4 wherein the timer means includes a rotatable output shaft having a slot therein, and the locking means carries a key, said key adapted to normally ride on said shaft as said shaft rotates until said key registers on the slot, said second release lever normally urging said key into said slot for rotational movement of said locking member to release said second lever.

6. In a time-delay release mechanism including means for engaging a load, a settable timing means, and locking means for releasably locking a load in said load-engaging means, and for unlocking said load-engaging means releasing the load responsive to the expiration of a preset time, the improvement comprising:

a. A rotatable output shaft driven by said timing means, said shaft having a key receiving slot;

b. A key carried by said locking means and disposed to ride on said shaft, said load engaging means normally urging said key against said shaft when said locking means is looking a load in said engaging mans; said key adapted to enter said slot and unlock said locking means when said key registers on said slot.

7. The release mechanism of claim 6 wherein'the load engaging means comprises:

a. An elongated lever rotatably connected to a support, a tan end thereof, said lever having a load-engaging hook adjacent said rotational connection and a pivot portion at the end opposite said connection;

bl A biased latch disposed adjacent said lever and rotatably connected at an end thereof to a support, said latch having a pivot-engaging portion adjacent said rotational connection and a locking portion at the end opposite said connection; said latch adapted to engage said pivotal portion of said lever and releasably engage said locking means at the locking portion thereof so that when said lever hook engages a load said latch connects said lever and said locking means until said locking means releases said latch.

8. The release mechanism of claim 6 wherein the settable timing means comprises:

a. A main spring attached to said output shaft, said mainspring rotatably driving said shaft;

b. An escape wheel drivingly connected to said output shaft,

distally to the key receiving slot;

0. Pallet means for selectively engaging said escape wheel and for regulating the advance of said wheel responsive to the drive of said mainspring;

d. Timer locking means for selectively engaging said pallet means to stop the advancement of said wheel and the rotation of said output shaft.

9. The timing means of claim 8 wherein the timer-locking means comprises:

a. A biased lever disposed adjacent said pallet means;

b. Resilient arresting means operably connected to said lever at an end thereof for selectively engaging said pallet means to arrest the advancement of said escape wheel responsive to the displacement of the end of said lever.

10. The locking means of claim 9 wherein said lever is a bellcrank with an end thereof operably engaging said arresting means, and said locking means further comprises a biased plunger pivotally connected to said crank at an end thereof opposite said arresting means whereby depression of said plunger displaces the end of said crank engaging said arresting means and said pallet and release of said plunger releases said pallet.

11. The release mechanism of claim 6 further comprising a settable, graduated indicator means disposed adjacent the key receiving slot on said output shaft for indicating the length of time necessary for said shaft to rotate until said key enters said slot releasing said load.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2497467 *Mar 3, 1947Feb 14, 1950Lockheed Aircraft CorpQuick disconnect coupling for cables
US2845676 *Apr 15, 1954Aug 5, 1958Eastern Rotorcraft CorpRelease mechanism with manual and power actuation
US3425739 *Nov 25, 1966Feb 4, 1969Us ArmyReleasable coupling
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4604772 *Oct 9, 1984Aug 12, 1986Itw-Ateco GmbhDevice for tensioning belts or the like
US5195223 *Jun 19, 1991Mar 23, 1993Tylaska Timothy TQuick release apparatus
Classifications
U.S. Classification24/68.00R, 368/97, 24/602
International ClassificationE05B43/00
Cooperative ClassificationE05B43/00
European ClassificationE05B43/00