US2447236A

US2447236A - Work holding fixture

Info

Publication number: US2447236A
Application number: US599077A
Authority: US
Inventors: Aldege L Dery
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-06-12
Filing date: 1945-06-12
Publication date: 1948-08-17
Anticipated expiration: 1965-08-17

Description

' Aug. 17, 1948. L, DE Y 2,447,236

WORK HOLDING FIXTURE Filed June 12, 1945 5 Sheets-Sheet 1 I veutor By 2mm min E/amzg Aug. 17, 1948. I 1 E 2,447,236

wonx nowme FIXTURE Filed June 12, 1945 :5 Sheets-Sheet 2 x ////l /////////1 v //l I: /////7 Inventor /w ije of circular milling fixture;

Patented Aug. 17 1948 U NI TED STATES PATENT O FFICE Y WORK' HOLDINGFIXTURE Aldege L. Dory, FineMeadow, Conn.

Application June 12, 1945, Serial No. 5995077 4 Claims. (01. 90-60) This invention relates to improvements in work holding fixtures and more particularly to the type of fixture used in connection with milling-operations. Such devices are commonly employed on milling machines to hold Work pieces to be milled though they may be employed for other operations such as grinding.

The object of the invention is rigidly to support one or more work pieces in position for a machine operation and to prevent its displacement as a result of the forces applied thereto.

Another object is a gang fixture in which a plurality of pieces may be held and firmly clamped during a machine operation.

Among its features, my invention embodies a plurality of jaw members supported by a fixed jaw, each of which is provided with a, pair of angular faces at one end, and a movable jaw adapted to be advanced toward the fixed jaw and the jaw members to clamp work pieces between the angular faces of adjacent jaw members and the fixed jaw whereby a three pointsupportis provided for each work piece.

Other features embody-relieving the jaw memhens in such a manner that'the work pieces are engaged by a slightly yielding pressureso' as to compensate for slight irregularities occurring in the sides of the work pieces which are engaged by the faces of the jaw members-and the movable Jaw.

Still other features embody the use of resilient jaw members or resilient clamping members which cooperate with the jaw members so as-to produce a cushioned holding effect on the work.

In the drawings:

Figure 1 is a top plan View of a milling fixture designed for straight line work and embodying my invention; v

Figure 2 is a transverse sectional view taken on the line2-2 of Figure'l; g

Figure 3 is a perspective view-ore. jaw member possessing the cushioning characteristics;

Figure 4 is a top plan view of a fixture adapted for use on a rotary milling machine andembodying my invention;

Figure 5 is a transverse sectional view taken on the line 5-5 of Figure 4;

Figure, 6 is a detail perspective-view of aresil- .ient'jaw memberwhich maybe used in conjunction with the fixture illustrated in Figure 4;

Figure '7 is a view similar toFigure 6 ofa'modified form of clamp jaw for use in conjunction with the type of fixture illustrated in Figure-4;

Figure 8 is a top plan view of a'modifiediorm Figure 9 is a transverse sectional View taken on theline 99 of Figure 8; and

Figure 10 is a perspective view of a modified form of jaw for use in connection with the fixture illustrated in Figure 8.

Referring to the drawings in detail, a milling fixture for use in straight line milling is designated generally l5 and comprises a fixed jaw it which is constituted of a U-shaped frame having at opposite ends legs 11. The ends oft-hese legs are drilled and tapped to receive retaining bolts M3 by means of which a movable jaw i9 is supported'in operative relation to the fixed jaw 15. Extending transversely through the legs I! of the fixed jaw are aligned openings for the reception of a retaining bar 2!, the purpose of which will be more fully hereinafter described. Extending through the bight portion [6 of the stationary jaw at spaced intervals are openings 22 "for the reception of bolts 23, the inner ends of which enter screw threaded openings 24' in the rod 21 previously referred to.

Mounted'between the arms I! of the U-shaped frame of thefixed jaw l5 are jaw members designated generally 25'. Each such jaw' member comprises a body 26 opening through the upper edge of which is .a slot 21 and opening through the lower edge of which is another slot 28. The rear wall of the slot 21 is formed with a recess 29 against the wall of which the rod 2| previously described is adapted to rest, When the jaw members 25 are in position within the'fixed jaw I5 the rod 21 is thrust through the opening 20 and the slots 29 and the screws 23 are tightened to securely hold the rear or inner ends of the jaw members against the bight portion l6 of the fixed jaw 15 as illustrated in Figures 1 and 2. As shownin Figure 1, the forward. ends of the jaw members 25 project beyond the ends of the arms l1 ofthe jaw member [5, and these forward ends are 'formed with inclined face .3!) which areadapted'to cooperate with the movable jaw-I 9 in clamping the-work pieces W inposition in the 'fixture. Each jaw member is relieved along one'side as at 3| from a point intermediate their ends so as to allow a slight resilience to compensate for irregularity in the work pieces W.

The

slots

21 and 28 cooperate to allow the jaw members25 to yield along its longitudinal axis so that the'work pieces W are clamped firmly. in position under a slightyielding pressure longitudinally of the jaw members.

3 having an upstanding flange 34 and an annular groove 35 at the junction of the body 33 with the flange 34. In this form of fixture the jaw members designated generally 36 are arranged radially so that the work pieces are held in a closed annular row.

Each jaw member 36 comprises a body 38 carrying at its lower rear end a tongue 39 which is adapted to seat in the annular groove 35 in order to lock the jaw member in place. A ring shaped cover plate 45 is attached to the upstanding flange 34 by suitable attaching means, such as screws 4| and overlies the upper faces of the jaw members 38 in order to hold them against accidental displacement. The end of each jaw member opposite the end carrying the tongue 39 is provided with a pair of inclined faces 42 which cooperate with the movable jaws to be more fully hereinafter described in clamping the work pieces W in the fixture. Like the previously described jaw members, each of the jaw members 36 is relieved along one side as at 43 to allow slight sideways motion in order to accommodate slight irregularities in the work pieces. As previously described, the body 33 is substantially ring-shaped in form and extending upwardly in concentric spaced relation with the flange 34 is a wall 44 which is provided with radial slots 45 in which movable jaw members 46 are adapted to slide. The slots 45 are so arranged that they align axiallywith the apices of the V-shaped grooves formed between adjacent jaw members 36, as will be clearly seen upon reference to Figure 4. As illustrated in Figure 5, each jaw member 46 is provided in its upper edge with a notch 41 for the reception of a compression coil spring 48, one end of which bears against the rear end of the recess 41, while the opposite end bears against a pin 49 carried by a cover plate 58, which is held in position on the annular wall 44 by means of fastening devices such as screws As shown, the rear or innermost ends of the movable jaw members 45 are inclined as at 52 for engagement with a frusto conical block 53, which is mounted to move axially through the ring-shaped body 33. Closing the lower open end of the passage through the ring-shaped block 33 is a cover plate 54 having an internal screw threaded opening formed axially therein for the reception of a screw threaded shaft 55, the inner end of which is swivelly connected as at 56 to the frusto-conical member 53, while the outer end carries a suitable cross bar (not shown) by means of which the shaft 55 may be rotated within the opening in the plate 54 so as to advance or retract the frusto-conica1 block 53 axially through the body 33. It will thus be seen that as the block 53 advances the movable jaw members 46 will be projected toward the stationary jaw member 35 through the contact of the inclined walls 52 of the jaw members 46 with the surface of the conical member 53. In this way the work piece W will be clamped between the outer ends of the movable jaw members 46 and the inclined faces 42 of the stationary jaw members 36.

In Figures 6 and '7, I have disclosed certain modifications which may be incorporated in the device just described. The stationary jaw members for instance, as illustrated in Figure 6 and designated generally 51, may be formed with slots 58 and 59 in order to provide a certain amount of longitudinal resilience in the jaw members 5'! which, it is to be understood, may be substituted for the jaw members 36. The functions of the slots 58 and 59 is essentially the same as that of the

slots

21 and 28 of Figure 3.

Alternately instead of providing the stationary jaw members with such slots, I may find it desirable to employ a jaw member such as that designated generally 60 with slots BI and 62 in order to provide the desired resilience when its work clamping end 63 is moved positively outward into work engaging position. When such a movable jaw member is used, it is obvious that the conventional jaw member 36 will be employed in the fixture illustrated in Figures 4 and 5.

In Figures 8 and 9 I have disclosed a further modification of my invention corresponding in many respects to the structure illustrated in Figures 4 and 5, but provided with a different form of movable jaw advancing means. In this type of device a body 64 of substantially circular form is provided at its peripheral edge with an upstanding flange 65 and at the junction of the flange 65 with the body 64 is formed with an annular groove 66. Formed concentrically with the body but spaced inwardly from the flange 65 is an annular channel 61 adjacent the outer peripheral edge of which is a similar channel or groove 68 of somewhat lesser depth and about one-half of the width of the channel 61. Extending inwardly from the side wall-of the body 64 and communicating with the

channels

61 and 68 is a bore 68, the purpose of which will be more fully hereinafter described.

Attached as by screws 18 to the body 64 concentric with the ring 65 is a disk H which is of a thickness substantially equal to the heighth of the wall or flange 65, which disk is provided with a plurality of radial grooves 12 in which movable jaws 13 are slidably mounted. Each of these jaws is provided with a depending lug '14 for a purpose to be more fully hereinafter described. Like the

jaws

25 and 51, the jaws 13 may also be provided with

vertical slots

15 and 16 so, if desired, a jaw 11 (Figure 10) having a depending lug l8 and in which the

slots

15 and 16 are omitted may be substituted.

Mounted for rotation in the groove 61 is a ring 19 carrying on its underside a series of gear teeth which ride in the groove or channel 68 previously mentioned. Extending into the bore 69 is a shaft 8| carrying at its inner end a pinion 82, which is adapted to mesh with the teeth 80 so that when the shaft is rotated, the ring 19 will revolve in the groove. A suitable cross bar 83 is fixed in the outer end of the shaft for the purpose'of facilitating manual operation of the shaft. Formed in the upper surface of the ring 19 is a spiral groove 84 into which therdepending lugs '14 of the movable jaw members 13 are received. Inasmuch as the groove 84 is of spiral formation it will be obvious that as the ring 19 revolves in its groove under the influence of the pinion 82 and shaft 8|, the movable jaw members 73 will be advanced or retracted according to the direction of the motion of the ring.

Seated against the flange 65 are stationary jaw members 85, each of which is provided with a depending lug 86 for entrance into the gro0ve'66 and the inner ends of these jaw members 85 are provided with inclined faces 81 which cooperate with the movable jaw members 13 in clamping a work piece in the fixture. It is obvious that the solid jaw members illustrated in Figure 10 may be substituted for the resilient jaw members 13 in which event I may find it desirable to employ the jaw mmbers'51 illustrated in Figure 6 in place of the jaw members 85 against the flange 65. It is also obvious that jaw members of the type illustrated in Figure 6 may be used in conjunction with the jaw members 73, without in any way departing from the spirit and scope of this invention.

In operation, it is obvious that work pieces W introduced into the spaces between the movable jaw members or member, as the case may be, and the stationary jaw members of any one of the forms of the invention herein shown will be clamped firmly against dislodgment when the movable jaw member is advanced. toward the stationary jaw members and each work piece will be suspended at three points. By reason of the release of the stationary jaw members, their free ends may move slightly from one side to the other in order to accommodate work pieces W having slight irregularities and that by the use of the resilient jaws or jaw members the work will be yieldingly yet firmly held in place when the movable jaw members are advanced into clamping position.

While in the foregoing there has been shown and described the preferred embodiment of this invention it is to be understood that minor changes in the details of construction, combination, and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as claimed.

I claim:

1. A work holdin fixture comprising a fixed jaw, a plurality of individual jaw members carried by the fixed jaw, a movable jaw, each jaw member comprising a substantially S-shaped body and having oppositely inclined work engaging faces at one end each of which cooperates with the movable jaw and a work engaging face of an adjacent jaw member in yieldingly clamping a work piece and means to advance the movable jaw toward the fixed jaw.

2. A work holding device comprising a fixed jaw, a plurality of individual jaw members carried by the fixed jaw, a movable jaw, each jaw member comprising a substantially S-shaped 6 body havin oppositely inclined work engaging faces at one end each of which cooperates with the movable jaw and a work engaging face of an adjacent jaw member in clamping a work piece.

3. A work holding fixture comprising a fixed jaw, a movable jaw, a plurality of individual jaw members carried by the fixed jaw, each individual jaw member comprising an S-shaped body with 'its longitudinal axis disposed toward the movable jaw, the end of each individual jaw member facing the movable jaw being provided with at least two inclined work engaging faces whereby when the movable jaw is advanced toward the fixed jaw work introduced into the fixture will be yieldingly clamped between the inclined faces of two adjacent jaw members and the movable jaw.

l. A work holding fixture comprising a fixed jaw, a movable jaw, a plurality of individual resilient S-shaped jaw members carried by the fixed jaw, each such jaw member having inclined work engaging faces each of which cooperates with the movable jaw and work engaging face of the next adjacent jaw member in yieldingly clamping a work piece.

ALDEGE L. DERY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,256,217 Fieldhouse Feb. 12, 1918 1,397,409 Duwelius Nov. 15, 1921 2,339,800 Oben-cy Jan. 25, 1944 2,346,053 Smith Apr. 4, 1944 FOREIGN PATENTS Number Country Date 25,666 Great Britain A. D. 1398 29,226 Great Britain Dec. 10, 1914 533,646 Germany Sept. 18, 1931