US1956588A - Scissors - Google Patents

Description

May 1, 1934.

M. PARKER ET AL SCISSORS Filed March 4, 1932 2 Sheets-Sheet l fiTOR M MO WI ATTORN EYS May 1, 1934. M. PARKER El AL SCISSORS Filed March 4, 1932 2 Sheets-Sheet 2 ATTORNEY-.5

Patented May 1, 1934 UNITED STATES PATENT OFFECE'.

SCIS SOR-S Application March 4, 1932, Serial No. 596,744

14 Claims. (01. 30-43) This invention relates to improvements in scissors, particularly detachable blade scissors such as described in Patent No. 1,814,959 issued to one of the present applicants.

The blades illustrated in that patent are so fine and wire-like that it is difficult to insert the thumb nail between the side of the blade at its inner end and the supporting shank or frame to free it from the latch and permit withdrawal. In accordance with the present invention we facilitate withdrawal of the blade by terminating the blade-supporting bead short of the inner or butt end of the blade so as to leave the butt exposed and accessible and laterally unsupported fora short distance so that it may be flexed sidewise. A notch in the blade cooperates With a latch on the frame to prevent accidental Withdrawal, while to remove the blade intentionally it is necessary only to open the scissors to their wide open position-thereby exposing the inner or butt end of each blade-and push outward and to the side against the exposed inner end of the blade with a coin or other convenient tool.

With the butt ends of the blades exposed and terminating short of the intersection of the operative edges when the scissors are in wide open position, it might happen that, in closing, the two opposing butt ends would interfere and so prevent the closing of the scissors. In order to avoid this we have constructed our scissors so that the cutting edges cannot touch until after the frames have closed slightly beyond the butt ends of the blades. We do this by providing a pair of interacting cam surfaces, one cam on the inner face of each frame between the pivot screw and the cutting edge, so positioned as to ride upon each other as the exposed butt ends of the blades pass, thus tilting the frames to separate the blades. In closing, when the ends-of the blades have passed, the cams move apart and the cutting edges come into shearing contact. As a further improvement we facilitate the mounting of the blade on the bead by cutting away, at its inner end, the lower flange which enters the undercut portion of the bead. Thus it is necessary only to place the inner end of the blade over the tip of the bead and shove inward. By this means the flange is easily and automatically aligned with the undercut groove which defines the'bead.

In the accompanying drawings we have illus trated a preferred embodiment of our invention.

.In these drawings Figure 1 is an elevation of a pair of scissors constructed in accordance with the present invention; Figure 2 is an enlarged detail of one frame showing the inner end of a blade mounted thereon; Figure 3 is a view similar to Figure 2 with the blade removed; Figure 4 is a still'further enlarged vertical section taken along line 44 of Figure 2; Figure 5 is an enlarged horizontal section through the inner end of the blade and its supporting bead showing the latch construction and taken along line 5-5 of Figure 4; Figure 6 is a perspective view of the inner end of the blade; Figure 7 is an enlarged section taken along line 7--7 of Figure 2; Figure 8 is an enlarged view showing the scissors in wide open position with the butt ends of the blades exposed for removal, and Figure 9 is a similar view showing the position of the parts just after the butt ends of the blades have passed each other in closing. 7

The scissors shown in Figure 1 comprise frames 1 pivoted together by means of the ordinary pivot screw 2. Extending along the operative edgeof each frame from the tip to a point somewhat in advance of the pivot screw is a bead or rail 3 defined by a shoulder 4.extending along 'the back of the shank and by a groove 5 in its shear face. On this bead is mounted a detachable flexible blade 6, of the type illustrated in Patent No. 1,814,959, provided with a flange '7 seated upon the shoulder 4 and a flange 8 seated within the groove 5. As illustrated most clearly in Figure 4 the rail or bead 3 is inclined slightly toward the plane of the shear face so that the blade 6, when mounted, is canted, say 5 or 10, with reference to the shear face, the sharpened edge 9 of the blade lying above the plane of the inner face of the frame.

As illustrated most clearly in Figures 3 and 7, the inner end of the bead 3 is cut away at 10 so that the flange 4 has no lateral support beyond that point, and the inner end of the blade can, therefore, be flexed inwardly away from the inner face of the frame. The cut-away portion of the bead extends well beyond the butt end of the blade leaving that end open and exposed as shown in Figure 2. y

Inorder to prevent the blade from slipping outward along the bead when in use, we prov1de a latch 11 near the inner end of the groove 5 which cooperates with a cut-out portion 12 in the flange 8 and adjacent web of the blade. As the blade is slid inward along the bead, that section of the blade beyond the cut-out rides up the inclined outer face of the latch 11 and snaps into position behind it, as shown in Figure 5. Although there is little possibility of further inward movement of the blade after its inner end has passed the cams 16' and 15'.

latch 11, we nevertheless make this impossible by providing the wall 14 beyond the' notch 11 against which the inner end of the flange 8 may abut, thus forming a lock against movement in either direction.

In order to facilitate mounting the blade upon the bead, which is done by a longitudinal sliding movement toward the. pivot, we cut away the flange 8 and a portion of the web of the blade at its inner end as illustrated at 13 in Figure 6. With a blade so constructed it is necessary only to place the end of the blade over the tip of the bead and. then slide it inward, the alignment of the flange 8 with the groove 5 being thus automatically effected.

In order to remove the blade when dulled the frames are swung to their wide open position, as illustrated in Figures 1 and 8, a coin or other convenient tool applied to the butt end of the blade and pressure exerted to swing the laterally un-- supported inner end free of the latch 11 and at the same time to slide the blade outward along the bead.

With the butt ends of the blades exposed, as illustrated in Figures 1 and 8, these inner ends would be very likely to interfere with each other and prevent closing of the scissors. To prevent this we haveprovided the inner faces of the frames with cams 15 and 15', one on the inner face of each frame between the pivot screw and the inner end of the blade, so positioned that, as the inner ends of the blades approach each other, these cams ride upon each other and tilt the frames just sufficiently to separate the blades. After the ends of the blades have passed, during closing, the cams ride down and the cutting edges are again brought into contact. These cams 15 and 15, therefore, make it impossible for the butt ends of the blades to interfere.

In Figures 8 and 9 we have also illustrated two additional cams 16 and 16' on the inner faces of the frames beyond the pivot screw. These cooperate to urge the cutting edges into contact throughout the shearing stroke. These cams are so placed that they cannot come into operation until the cams 15 and 15 have separated. Likewise, the cams 15 and 15' cannot come into operation while the cams 16 and 16 are in contact. In Figure 9 we have illustrated the frames with the cams l6 and 16 moving into cooperative relationship and cams 15 and 15' moving out of such relationship. The angular distance between the forward end of cam 16 and the rear end of cam 15 is not less than 180. The same is also true for The cams l6 and 16 are described and claimed more particularly in our co pending application, Serial No. 596,742 filed concurrently herewith.

We claim:

1. Scissors comprising a frame, a'flexible blade slidably mounted on the operative edge thereof, means for supporting the blade against lateral flexure except for a short distance adjacent its inner end, and a latch engaging the inner end of the blade beyond the lateral support for holding the blade against longitudinal displacement.

2. Scissors comprising a frame, a bead extending alow the operative edge thereof, a flexible blade slidably mounted upon the bead and extending beyond the inner end of the bead, and a latch engaging the blade beyond the inner end of the head for holding the blade against longitudinal displacement, the frame being cut away beyond the inner termination of the blade to expose its butt end. I

3. Scissors comprising a frame, a bead extending along the operative edge of the frame, a longitudinally slidable blade mounted upon the bead, a latch engaging the blade adjacent its inner end for preventing longitudinal displacement, and a cut-out section at the inner end of the bead extending from a point within the blade to a point beyond whereby the butt end of the blade is exposed and whereby the butt end of the blade may be flexed to disengage the latch.

4. Scissors comprising a pair of pivoted frames, a bead extending along the operative edge of each frame, flexible blades slidably mounted upon the beads, ;a latch engaging each blade adjacent its inner end for preventing longitudinal dis placement, a cut-out section at the inner end of each bead extending from a point within each blade to a point beyond, whereby the butt end of each blade is exposed and whereby the butt end of each blade may be flexed to disengage the latch, and means for keeping the butt ends of the blades out of contact as they pass.

5. Scissors comprising a pair of pivoted frames, the cutting edge of one frame terminating in an exposed butt end short of the intersection of the frames when the scissors are in wide open position, and means for keeping said exposed butt end out of contact with the other cutting edge as they pass each other.

6. Scissors comprising a pair of pivoted frames having cutting edges terminating in exposed butt ends short of the intersection of the frames when the scissors are in wide open position, and cams on the frames for separating the frames as the exposed butt ends of the cutting edges pass each other.

7. Scissors comprising a pair of pivoted frames having cutting edges terminating in exposed butt ends short of the intersection of the frames when the scissors are in wide open position, cams on the frames for separating the frames as the exposed butt ends pass each other while the scissors are being opened, and other cams for urging the blades into contact after their butt ends have passed each other while the scissors are being closed.

8. Scissors comprising a pair of pivoted frames, longitudinally slidable blades mounted on the operative edges thereof and terminating short of the intersection of the operative edges when the scissors are in wide open position, and means for keeping the blades out of contact as their inner ends pass each other.

9. Scissors comprising a pair of pivoted frames, blades removably mounted thereon terminating in exposed butt ends short of the intersection of the operative edges when the scissors are in wide open position, and means for keeping the butt ends of the blades out of contact as they pass each other.

10. Scissors comprising a pair of pivoted frames, a bead extending along the operative edge of each frame, a blade longitudinally slidable upon each bead and terminating in an exposed butt end short of the intersection of the operative edges when the scissors are in wide open position, and cams on the inner faces of the frames for separating the blades as their exposed butt ends pass.

11. Scissors comprising a pair of pivoted frames, longitudinally slidable blades mounted on the operative edges thereof and terminating short of the intersection of the operative edges when the scissors are in wide open position, means for keeping the blades out of contact as their inner ends pass each other, and other means for urging the blades into contact after their inner ends have passed each other while the scissors are being closed.

12. Scissors comprising a pair of pivoted frames, a flexible blade slidably mounted on the operative edge of each frame, means for supporting each blade against lateral flexure except for a short distance adjacent its inner end, a latch engaging the inner end of each blade beyond the lateral support for holding the blade against longitudinal displacement, a cut-out section in each frame beyond the inner termination of the blades to expose their butt ends, and cams on the inner faces of the frames for separating the blades as their exposed butt ends pass.

13. Scissors comprising a pair of pivoted frames, a bead extending along the operative edge of each frame, a blade longitudinally slidable upon each bead and terminating at a point beyond the inner end of the bead but short of the intersection of the operative edges when the scissors are in wide open position, cooperating cams on the inner faces of the frames adjacent the pivot for separating the blades as their butt ends pass each other while the scissors are being opened, and other cams for urging the blades into contact after their butt ends have passed each other while the scissors are being closed.

14. A detachable blade for scissors having a longitudinal recess shaped to embrace an undercut bead on the scissors shank, a flange to hold the blade against lateral displacement, and a cutout in the inner end of the flange whereby the lead end of the blade can be placed laterally over the tip of the bead to align the blade and bead for a longitudinal sliding interfit.

MORGAN PARKER. JOHN W. B. LADD.

Ill?

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