US 3496807 A
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Feb. 24, 1970 P. D. JONES ETAL TWEEZERS 2 Sheets-Sheet 1 Filed Dec. 27, 1967 W R A o M T a N Feb. 24, 1970 P. D. JONES ETAL 3,496,807
EWEEZERS 1 I Filed Dec. 27, 1967 v 2 Sheets-Sheet 2 INVENTOR6. PE/CE Q JONES Mg/V67 14 fi4066K64M/V/1/ AWWMMK 3,496,807 TWEEZERS Price D. Jones and Sidney W. Ploeckelmann, Manhattan Beach, Calif., assignors to Swiss American Precision Imports, Inc., El Segundo, Calif., a corporation of California Filed Dec. 27, 1967, Ser. No. 694,011
Int. Cl. B25b 9/02 US. Cl. 81-43 4 Claims ABSTRACT OF THE DISCLOSURE The device is a tweezers or tool particularly constructed and adapted for picking up and handling thin, fragile objects such as silicon wafers. The leg portions of the tweezers may be of generally conventional construction, the noses or jaws of the tweezer parts or leg being particularly configurated for the purpose intended. In a preferred form, the jaws include one jaw which is offset from its leg and having an extended tapering nose tapering to a knife edge, the taper being on the inside of the jaw and the other side of the jaw being flat adapting it to engage a flat horizontal surface. The other jaw comprises a jaw in an angular position with respect to its leg located so that when the jaws are brought together this jaw is in a position adjacent to the-offset of the other jaw, whereby the object can be grasped between the jaws at a position adjacent to the offset and at the edge of the object.
Summary of the invention The device of the invention is an improved tweezers or tool particularly adapted and configurated for the handling of thin, fragile objects such as, for example, silicon wafers that may have electrical circuitry etched thereon. The tweezers or tool is particularly adapted for picking up such objects or items from a fiat horizontal surface without scratching the etched circuitry beyond A3 inch from the outer edge of the object or wafer.
In a preferred form of the invention the legs of the tweezers or tool may be of generally conventional construction, either having intermediate crossing portions or not having intermediate crossing portions. In the form of the invention wherein the tool legs have intermediate crossing portions, when the handle portions of the legs are pressed together the jaws open and the jaws close when these portions are released.
The improvement of the invention resides particularly in the form and configuration of the jaws, at the ends of the legs of the tool or tweezers. In a preferred form of the invention these jaws comprise a first jaw on one leg which is offset from the leg and which has an extending jaw portion which is tapered to a knife edge, the taper being on the inside of the jaw and the other side of the jaw being flat for engaging a flat horizontal surface. The other jaw is positioned at an angle to its leg and located so that when the jaws close this jaw comes into a position generally parallel to the offset of the other jaw and in a position to grasp the edge of the object between the jaws. This type of configuration of the jaws greatly facilitates picking up, or scooping thin delicate object such as silicon wafers from a fiat horizontal surface on which they may be lying. The primary object of the invention is to facilitate this particular purpose in picking up and handling objects of this type. The offset in the lower jaw, that is, the portion which offsets the jaw itself from the leg, provides a shoulder or stop which prevents scratching of the upper surface of the wafer beyond A; inch from the edge during its handling. The realization of this end is one of the objects of the invention.
Preferably, the jaws are relatively wide, providing relanited States Patent tively wide positive contacting area to thereby prevent damage and cracking of the delicate or fragile wafer or object, and whereby the object may be held firmly in any position at any time. The realization of this end constitutes a further object of the invention.
The offset points or jaws of the tool make the handling of objects easy and comfortable for the operator by keeping the hand holding the tool away from the table or other flat surface. The realization of this end constitutes a further object of the invention.
Further objects and additional advantages of the invention will become apparent from the following detailed description and annexed drawings wherein:
FIGURE 1 is a perspective view of a preferred form of the invention.
FIGURE 2 is a side view of the jaws of the tweezer or tool of FIGURE 1.
FIGURE 3 is a view like FIGURE 2 illustrating the picking up or scooping of a thin fragile wafter.
FIGURE 4 is a sectional view through the jaws of the tweezer or tool of FIGURES 1 to 3, illustrating the offset of the jaws.
FIGURE 5 is a perspective view of a slightly modified form of tool, wherein the legs are of slightly different configuration.
FIGURE 6 is a sectional view through the offset jaws of the tool or tweezers of FIGURE 5.
FIGURE 7 is a perspective view of a modified form of tool or tweezers wherein the legs have intermediate crossed portions so that the jaws open upon applying pressure to the legs.
FIGURE 8 is a side view of the tool of FIGURE 7 illustrating the grasping of a thin wafer.
FIGURE 9 is a view like that of FIGURE 8 showing the jaws closed on the wafer.
FIGURE 10 is a sectional view through one leg of the tool or tweezers of FIGURE 9.
Referring now more in detail to FIGURES 1 to 6 of the drawings, numeral 10 designates a preferred form of the tool or tweezers having legs 12 and 14 which are similar and generally symmetrical and having different forms of jaws at their ends. Preferably the legs may be made from a non-magnetic, stainless, acid-resistant steel. The legs are joined at the end opposite the jaws, preferably by spot welding at the area designated by the numeral 16.
FIGURES 2, 3 and 4 illustrate the configuration of the jaws of the tool. The legs 12 and 14 at the jaw ends are tapered as shown at 18 and 20, the sides of the tapered parts being generally arcuate. At the end of the tapered part 18 is the jaw 24 which has a portion having the same width as the end portion of the tapered part 18 and positioned at an angle, substantially a right angle, relative to the leg 12.
At the end of the tapered part 20 of the leg 14 is the jaw 26. This jaw is at the end of an offset portion 28 which is at an angle of substantially degrees to the tapered end toward 20 of the leg 14. At the end of the offset or offset portion 28 is the jaw 26 which has a width the same as the width of the end part of the tapered portion 20. The upper side of this jaw is tapered as shown at 32 to a knife edge 34 at its end. The lower surface of this jaw as designated at 36 is flat adapting it to be placed flat against a horizontal surface or table as shown.
When the legs 12 and 14 which are resilient or flexible, are squeezed together, the jaws come into juxtaposition as shown in FIGURES 2 and 3. The jaw of 24 is approximately parallel to the offset or offset portion 28 and spaced therefrom as shown. The offset 28 provides a stop or shoulder preventing the jaws from engaging the flat, delicate object or wafer such as shown at 40 more than approximately inch inwardly from the edge thereof.
3 The edge part of the object is grasped between the jaw 24 and the jaw 26 as shown, with the edge of the object against the shoulder formed by the offset 28. Thus, it may readily be seen all the objects of the invention as set forth in the foregoing are realized.
Delicate, fragile items or objects can readily be scooped or picked up and grasped in the manner illustrated without damage to them or to the etching on them.
FIGURE shows a slightly modified form of the invention, wherein the jaws of the tool are like those of FIGURES 1 to 4. The legs in this form of the invention are slightly different, however. The upper leg 42 has a configuration as shown in FIGURE 5, having an intermediate outwardly bowed and ribbed or knurled part 44. The lower leg 46 is generally symmetrical except for the jaw part having a similar intermediate outwardly bowed and ribbed or knurled part 48. The operation of the tool or tweezers of FIGURE 5 is similar, the jaws coming together for grasping a thin, fragile object when pressure is applied to the legs, that is, when the legs are squeezed together. FIGURE 5 shows the tool scooping or picking up a postage stamp 50.
FIGURES 7 to show a modified form of the invention adapted to a tool or tweezers of the type having intermediate crossed portions whereby when the legs are squeezed together the jaws open, the jaws coming together when the legs are released. The jaws in the tool of FIGURES 7 to 10 are like those of the previous embodiment. In FIGURES 7 to 10 the tool has a leg 60 and another leg 62. The leg 60 has an intermediate angular narrowed offset part 64 joined to tapered end part 66, at the end of which is the jaw 26. The offset part 64 has a cut out portion 70 positioned at the intermediate area where the legs cross each other. The leg 62 has a similar angular offset 64 connected to tapered end portion 72 at the end of which is the jaw 24. The angular offset part 64 has in it a cut out 70', the two cut outs being adjacent to each other at the intermediate part of the legs where they cross.
The operation of the tool of FIGURES 7 to 10 is similar to that of the previous embodiments. However, in this form of the invention, as illustrated in FIGURES 8 and 9, when the legs 60 and 62 are squeezed together the jaws separate as illustrated in FIGURE 8, by reason of the legs having the offsets therein and their crossing each other at an intermediate point. When pressure is released on the legs, the jaws come together as shown in FIGURE 9 for grasping of fragile objects. The form of the invention as shown in FIGURES 7 to 10 accomplishes the same objects and has advantages similar to those of the previous embodiment.
From the foregoing those skilled in the art will readily observe and understand the nature and construction of the invention, and the manner in which it realizes and achieves all of the objects and advantages as set forth in the foregoing, as well as many additional advantages that are apparent from the detailed description.
The foregoing disclosure is representative of preferred forms of the invention and it is to be interpreted in an illustrative rather than a limiting sense.
What is claimed is:
1. A tweezer tool comprising:
a pair of resilient legs fixed together at one end, their free ends being movable toward and from each other;
one of said legs having an offset portion adjacent its free end, extending generally laterally thereof away from the other leg and defining a shoulder facing said free end;
a first jaw at the outer end of said offset portion, said jaw being of substantial width and extending generally perpendicular thereto and having upper and lower opposed flat faces tapering toward each other to define a knife edge at the outer end thereof; and
the other leg having a second jaw portion at its free end extending laterally thereof toward said one leg outwardly of and generally parallel to said shoulder and having a broad end surface, said second jaw portion being of such length that its end surface may engage the upper of said faces when said free ends are moved together.
2. A tweezer as defined in claim 1 wherein said end surface is substantially flat and of substantially the same width as said upper face.
3. A tweezer as defined in claim 1 wherein said legs are resiliently biased, at their said one end, to urge said jaws apart.
4. A tweezer as defined in claim 1 wherein said legs are resiliently biased, at their said one end, to urge the adjacent portions of said legs apart; intermediate portions of said legs being arranged in crossed relation whereby said jaws are urged toward each other by said bias.
References Cited UNITED STATES PATENTS 450,266 4/ 1891 Truax. 745,071 11/1903 McKibben 81-43 784,803 3/ 1905 Moylan.
3,218,696 11/1965 Dritz 8l43 X ROBERT C. RIORDON, Primary Examiner ROSCOE V. PARKER, 1a., Assistant Examiner