US2717714A

US2717714A - Grommet setting tools

Info

Publication number: US2717714A
Application number: US390385A
Authority: US
Inventors: Robert G Haley
Original assignee: Boeing Co
Current assignee: Boeing Co
Priority date: 1953-11-05
Filing date: 1953-11-05
Publication date: 1955-09-13
Anticipated expiration: 1972-09-13

Description

R. G. HALEY 2,717,714 GROMMET SETTING TooLs sept. 13, 1955 Filed Nov. 5, 1953 nited States Patent Olice 2,711,714 Patented Sept. 13, 1955 nl. it

enum/rar snTTiNG roots Robert G. Haley, Seattle, Wash., assigner to Boeing Airplane Company, Seattle, Washington, a corporation of Delaware Application November 5, 1%3, Serial No. 390,335

5 Claims. (Cl. 218-42) Many airplane cabin interiors and the like are inished by fabric panels. These panels are frequently supported by engaging grommet-reinforced holes in the fabric with iixed studs on the structure. At times, due to last-minute changes or special installations, the outline of a panel must be varied, and grommets must be inserted to enable mounting of the revised edge shape. Not infrequently the attachment of such grommets must be accomplished within rather cramped quarters, where the use of a power or impact tool is impracticable, and where there is little room for extensive movement of a hand lever to operate a grommet-setting tool, and yet the work must of necessity be accomplished by a hand-operated tool.

The present invention is designed to accomplish these ends neatly, expeditiously and effectively, and by a handoperated tool which is simple in construction and easy to operate, both for the setting or crimping of the grommet and for the disengagement of the tool after the setting is completed.

In distinction to other grommet-setting tools of which I am aware, the tool of the present invention involves a high mechanical advantage, and yet requires but limited movement of hand-operated parts, such as will not, for example, interfere with the fabric to which the grommet is being applied. However, the device operates by a simple squeezing action repeated a number of times, and incorporates a ratchet type device, wherefore it is the more specific object of the present invention to provide a ratchet-operated grommet-setting tool having the capabilities and advantages outlined above, and yet of simple construction and simple in operation.

The invention is shown in the accompanying drawings in a presently preferred form of embodiment, and the details thereof and the principles which it embodies will ybe more fully brought forth in the following specification and claims.

Figure 1 is in general a side elevational view, but with various parts broken away in section to illustrate the interior construction and cooperation of the parts, at the beginning of a grommet-setting operation.

Figure 2 is a view similar to Figure l, but showing parts now in the set or completed position.

Figure 3 is a view similar to Figures 1 and 2 but with the parts now in the relative positions they would occupy during disengagement, after completion of the grommetsetting operation.

Figure 4 is a transverse sectional view taken substantially on the line 4-4 of Figure 3.

The tool incorporates what may be termed an abutment or anvil, generally indicated at 10, which supports a die 1 properly formed for the crimping operation upon the grommet half G1 at one side of the grommet. Rigidly secured to the anvil and directed laterally therefrom is a handle 11. The anvil is provided with a bore 12, usually round in cross section, which is coaxial with the die 1. Likewise it is recessed, the recess in this particular instance being in the form of a slot 13 which extends inwardly from the side opposite the die and from the side opposite the handle to intersect the bore 12.

A lever 2 is pivotally mounted at 21 upon the anvil 10, and extends across to the side opposite the bore 12 and generally alongside of or beneath the handle 11. Intermediate the pivot at 21 and the location of the bore at 12 the lever is provided with a transverse pin 22 by means of which the force is to be applied, and so the lever becomes a lever of the second class. As may be seen in Figure 4, the lever is forked at its pivoted end and the anvil may be slotted, as indicated at 14, for passage of and to enable swinging of the pin 22 as the lever 2 is squeezed and drawn toward the handle 11, or is permitted to swing away from the handle.

`A punch 3 cooperates with the die 1 to crimp the opposite half G2 of the grommet, and this punch isl formed with a stern 31, preferably round in cross section and coaxial with the punch, which enters the bore 12. This stem is provided with numerous ratchet teeth 30, all having their shouders facing downwardly or toward the punch 3. Supported within the recess or slot 13 is a ratcheting feed dog 4 formed with teeth 40 which are complemental to the teeth 30 of the stem, that is, which have their shoulders facing upwardly. This feed dog 4 is sufficiently loosely supported within the recess that it may move toward the stem and away from it, and upwardly and downwardly with respect to the axial extent of the stem. It is urged downwardly by spring means such as that indicated at 41, and its downward movement is stopped by its seating eventually upon the bottom ledge 15 of the slot 13. Preferably the lower portion of the feed dog 4, that which is nearer the punch 3, is sloped as indicated at 42 (see Figure 3), the slope being located immediately above the pin Mk2/hereby when that pin engages the slope 42 as the pin rises, the reaction between them will urge the loosely mounted feed dog 4 towards or more firmly into engagement with the teeth 30 of the stem, in addition to the upward component, and so upward movement of the pin 22, caused by swinging of the lever 2 toward the handle 11, will produce a strong upwardly acting force on the stem and on the punch 3, tending to draw the punch toward the die 1.

The leverage is such that only a small amount of angular movement of the lever 2 is required to effect approach of the punch toward the die by a distance equivalent to the spacing between two or more of the complemental teeth on the dog 4 and stem 31. The tooth spacing is not large. A holding dog 5' is mounted in the anvil, in position also to engage the teeth 30, and is spring-urged by the spring 50 into engagement with these teeth. This holding dog 5 will prevent retrograde movement of the punch, that is, will prevent its movement axially away from the die, following approach and during the reverse swinging of the lever 2 and downward movement of the feed dog 4. In consequence, it only requires a few brief squeezes, at high mechanical advantage and of small amplitude, between the handle 11 and the lever 2 to eifect suiiicient operative approach of the punch toward the die to accomplish crimping of the grommet G1, G2 which is interposed between them. The beginning of this operation is illustrated in Figure 1 and the completion thereof in Figure 2.

The operation having been completed, it becomes necessary to disengage the punch and die from the grommet. This is very simply effected by rotating the stem 31 until its teeth 30 are disengaged by this rotational movement from the teeth 46 of the feed dog 4 and from the holding dog 5. Such disengagement pushes the two dogs to the right, as seen in Figure 3, so that they bear now against the cylindrical, nontoothed portion of the stem 31, whereupon the stem may be withdrawn very readily from the bore 12. Rotation of the stem to eifect such disengagement may be accomplished by providing the punch with a knurled exterior, as indicated at 33.

It is believed the manner of use of the tool will be self-apparent. The stem 31, separated from the anvil, is pushed through the hole in the fabric F from the back Side, having first received a grommet half G2 in contact with the punch. Next a complemental grommet half G1 is applied on the stern above the fabric, and the stem is inserted within the bore 12 until its teeth 30 engage one or more of the teeth 4E) of the feed dog 4. Thereupon the lever 2 is pumped back and forth, alternately squeezing it toward the handle 11 and releasing it for retractive movement, and each such approach of the lever toward the handle advances the stem, with the dog 4, upwardly where it is held in its position of approach as between the punch and the die by the holding dog 5. Eventually the punch and die react upon the respective grommet halves to force these into operative engagement through and at opposite sides of the fabric,

as is seen in Figure 2, whereafter, by simple rotation of the stern and punch the stems teeth are disengaged from the teeth of the dogs, and the punch may be withdrawn in the manner suggested in the dash-line showing of Figure 3. Because of the small extent of the swinging movement of the lever 2, it is never necessary for the latter to swing so far as to contact and be interfered with by the fabric, and the leverage is great enough to effect proper hand squeezing and forming of the grommet, yet the operation can be performed in a very short space of time.

I claim as my invention:

1. A grommet setting tool comprising an anvil formed with a die and with a bore axially aligned with a bore in the die, the anvil having a recess alongside its bore, formed with parallel opposite walls, a handle extending laterally from said anvil and generally in parallelism with said walls, a lever pivotally mounted upon the anvil, close alongside said bore, and extending alongside said handle for approach towards and recession from the latter, a punch formed for cooperation with said die but separable therefrom for application to and disengagement from the work, a stern carried by and coaxial with said punch and slidable, during setting, within the anvils bore, said stern being formed with ratchet teeth spaced along its length, a feed dog loosely mounted and freely slidably received and guided within the anvils recess for bodily movement in directions both axially and radially with respect to the anvils bore, and formed along its edge which is adjacent the bore with teeth complemental to the stems teeth, said feed dog being spring-urged to engage its teeth with the stems teeth, means operatively interengageable between said lever and said feed dog, including cam means operable to urge the dog within the recess bodily towards the stern, and also axially of the stem, to shift the stem engaged by the dogs teeth axially in the sense to effect limited approach of the punch to the die, upon swinging of said lever in a given sense with relation to the handle, and a holding dog supported in said anvil, and springurged into engagement with the stems teeth, to retain the stem in each shifted position during swinging of all) Gil

the lever away from the handle preparatory to a further approach of the punch towards the die.

2. A grommet setting tool as in claim 1, characterized in that the feed dog is formed with an inclined surface, and a pin carried by the lever and engaged with such inclined surface, which together constitute the cani means to shift the feed dog, the slope of the inclined surface being so directed, relative to the path of the pin and the relative positions of the levers pivot and of the stem, as to urge the dogs teeth during each feed movement towards the stems teeth.

3. A grommet setting tool as in claim 1, characterized in that the stem is substantially circular in cross section, and rotatable within the anvils bore, but the ratchet teeth are formed on one side only of the stern, both the ratchet dog and the holding dog being located to engage such teeth during setting, whereby upon rotation of the stem from dog-engaged position its teeth may be disengaged from the two dogs, and the stern may be withdrawn endwise from the bore.

4. P grommet setting tool comprising an anvil formed on one end with a die and with a bore axially aligned with a bore in said die, a handle rigid with and extending laterally from said anvil, said anvil being slotted in a face opposite the die and the handle, a lever of the second class pivotally mounted upon said anvil and extending radially past said bore and generally alongside said handle, for swinging approach towards and recession from the latter, a punch formed for cooperation with said die to crimp an interposed grommet, a stern carried by and coaxial with said punch and slidably received, during setting, within the anvils bore, ratchet teeth formed along one side only of said stem, a feed dog received within the anvils slot, and located intermediate the bore and the levers pivot, teeth formed on said feed deg and engageable with the stems teeth, spring means urging the feed dogs teeth into engagement with the sterns teeth, a pin received in said lever and positioned for engagement beneath said feed dog to lift the latter, and so to effect limited approach of the punch towards the die, and a holding dog received in the anvil and spring-urged into engagement with the stems teeth, to retain the punch in a shifted position during swinging of the lever away from the handle preparatory to a further limited approach of the punch towards the die.

5. A grommet setting tool as in claim 4, including a knurled head on the punch, at the side opposite the stern, said stem being substantially round in cross-section, and rotatable within the anvils bore, and its teeth being located at one side only of the stem, whereby upon its rotation by said knurled head, said teeth are disengageable from the two dogs, for axial withdrawal of the stem.

References Cited in the ile of this patent UNITED STATES PATENTS 2,115,251 Buck Apr. 26, 1938 2,170,323 Gorshkoif Aug. 22, 1939 2,399,776 Wiesmann May 7, 1946 2,582,417 Croessant Ian. 15, 1952