US 2689400 A
Description (OCR text may contain errors)
Sept. 21, 1954 M. A. MIRANDO 2,689,400
KNIFE HANDLE AND TO METHOD AND APPARATUS FOR MAKING THE SAME a Filed Aug. 21, 1951 4 Sheets-Sheet 1 TIT:
INVENTOR. MICHAEL A. MIRANDO ATTORNEY P 21, 1954 M A. MIRANDO 2,689,400
KNIFE HANbLE AND TO METHOD AND APPARATUS FOR MAKING THE SAME Filed Aug. 21, 1951 4 Sheets-Sheet 2 J00 A Goya 10254 J 6 58 3/ 56 \"S w r Q \////vi p W 5// t U W.
89 J 98 68 60 J12 5g IN V EN TOR.
MICHAEL A. MIRANDO BY ATTORNEY Sept. 21, 1954 M A MlRANDO 2,689,400
KNIFE HAN'DLE' AND TO METHOD AND APPARATUS FOR MAKING THE SAME Filed Aug. 21 1951 4 Sheets-Sheet 4 T LL .15.
INVENTORA MICHAEL A. MIRANDO ATTORNEY Patented Sept. 21, 1954 D KNIFE HANDLE AND TO METHOD AND APPARATUS FOR MAKING THE SAME Michael A. Mirando, Providence, R. I., assignor to Imperial Knife Company,lnc., Providence, R. L, a corporation of Rhode Island Application August 21, 1951, Serial No. 242,874
7 Claims. (Cl. 30164) This invention relates to knife handles and to methods and apparatuses for making the same.
More particularly, the invention pertains to a knife handle having ornamental scale covering members.
The present invention is an improvement over the invention shown, described and claimed in United States Letters Patent No. 2,170,537. issued August 22, 1939, for Knife Handle and Component Parts Thereof, and United States Letters Patent No. 2,284,833, issued June 2, 1942, for Method and Apparatus for Making Knife Handles and Component Parts Thereof.
A knife handle of the type to which the present invention relates usually consists of a sheet metal scale having bolsters on the ends thereof, the scale being overlain by a thin ornamental cover between the bolsters whereby the handle appears to constitute a solid ornamental side piece.
In a knife handle of the character described the ornamental cover is made from a sheet of synthetic plastic material having edge portions side piece.
It is the primary object of the present invention to provide an improved knife handle of the character described and a method and apparatus for making the same which will overcome the foregoing drawbacks.
It is another object of the present invention to provide an improved knifehandle of the character described and a method and apparatus for making the same which are such that the cover will remain sharply curved where it is folded around the lateral edges ofthe knife.
It is another object of the present invention to provide an improved knife handle of the character described and a method and apparatus for making the same which are such as toenhance the grip of the cover on the scale whereby even after a long period of time the cover will remain in intimate contact with the scale and thereby retain its resemblance to a solid ornamental side piece.
It is another object of the present invention to provide an improved knife handle of the character described which may include an irregular outer surface instead of the smooth outer surface presently characteristic of such handles.
Other objects of the invention will in part be obvious and in part will be pointed out hereinafter.
The invention accordingly consists in the features of construction, combinations of elements, arrangements of parts and series of steps which will be exemplified in the handle units, apparatuses and methods hereinafter described and of which the scope of application will be indicated inthe appended claims.
In the accompanying drawings in which are shown several of the various possible embodiments of the invention,
Fig. l is a rear perspective view of a scale;
Fig. 2 is a perspective view of a cover;
Fig. 3 is a rear perspective View of a handle unit consisting of a scale and cover combined in accordance with the present invention;
Fig. 4 is an enlarged sectional view taken substantially along the line 44 of Fig. 3;:
Fig. 5 is an enlarged longitudinal central sectional view taken substantially along the line 5-5 of Fig. 4;
Fig. 6 is a front elevational view of an apparatus embodying the instant invention for mounting the cover on the scale, said apparatus being shown in its idle, i. e. starting, position;
Fig. '7 is a sectional view taken substantially along the line 1-1 of Fig. 6;
Fig. 8 is an enlarged sectional view taken substantially along the line 88 of Fig. 7;
Figs. 9, 10, 11 and 12 are views similar to Fig. 8 but showing the apparatus at progressively later stages of its operation;
Fig. 13 is a sectional view taken substantially along the line l3l3 of Fig. 8;
Fig. 14 is a rear perspective view of a scale embodying a modified form of the invention;
Fig. 15 is a perspective view of a cover adapted to be mounted on the scale of Fig. 14;
Fig. 16 is a rear perspective view of a handle unit consisting of the scale of Fig. 14 and cover of Fig. 15 combined in accordance with a modified form of the invention;
Fig. 1'! is a front view of the handle unit shown in Fig. 16;
Fig. 18 is an enlarged sectional view taken substantially along the line lB-lB of Fig. 16;
Fig. 19 is a view similar to Fig. 7 of an apparatus for mounting a cover on a scale to make a handle unit such as shown in Fig. 16;
Fig. 20 is an enlarged fragmentary sectional view taken substantially along the line 20-40 of Fig. 19; and l Fig. 21 is a sectional view taken substantially along the line 2l--2l of Fig. 20. 7
Referring now in detail to the drawings, and more particularly to Figs. 1-13, the reference numeral 30 denotes a knife handle unit constructed in accordance with the present invention, the unit including a scale 32 (Fig. 1) and a cover 34 (Fig. 2).
The scale is conventional, the same being fully shown and. described in said Letters Patent Nos.
2,170,537 and 2,284,833. By way of example the scale is stamped or pressed from sheet metal to an elongated shallow cup shape including a pair of raised arched end portions 36, 38 which form the bolsters of the handle unit and a depressed, i. e. inset, central arched portion 40 intermediate the bolsters. The lateral edges ofthe depressed central portion are inset from the peripheral edges of the bolsters to provide shoulders 42. The depth of the shoulders and the extent to which the central portion is depressed are substantially the same, being about equal to-the thickness of the cover 34.
Although, as shown, the lateral edges of the cover may be symmetrical with respect to its longitudinal axis, it is within the scope of this invention to employ asymmetrically arranged edges of the kind customarily used in certain types of knives.
Suitable means ma be provided, as for example, rearwardly extending tabs 4d 'at the tips of the scale, to aid in securing the handle unit-to a knife frame.
The cover '34 preferably is fabricated from heat-plasticizable self-form-maintaining sheet material, for example, a synthetic thermoplastic resin such as cellulose nitrate, cellulose acetate, cellulose acetate butyrate, an acrylic resin, a polyamide resin, a polyester resin, or a vinyl polymer or copolymer. It also is within the scope of the invention to employ a thermosetting resin, for example, a phenol or urea formaldehyde condensation product, although in such case in lieu of the heating means hereinafter described for plasticization, an equivalent means such as a" be fitted between the bolsters and the marginal edge portions of the cover can'be folded around the lateral edges of the scaleand'tucked in back of the same.
The cover is placed onthe external surface of the arched central portion and'the marginal edge portions of the cover are folded around "thelateral edges of the scale'and broughtbe'neaththe same. The'folds are locally'plasticized, as by the application of heat and pressure, so as to permanently set the'folds and so that upon deplasticization a controlled slight transverse shrinkage of the cover willtake place whereby'to render the cover drumtight.
To make certain that there is no relaxation from this tensed condition and that the folds in the cover closely follow the thin lateral edges of the scale, pursuant 'to the invention the infolded marginal edge portions of the cover'between the folds and the lateral edges of the cover are also plasticized and are pressed during plasticization into intimate contact with the marginal edge portions of the undersurface of the scale, without, however,plasticizing the portion of the cover on the front of the scale. Additionally'to insure that such intimate contact will be maintained for a long period of time, in further pursuance of the invention the infolded marginal edge portions of the cover are provided during plasticization with a large number of closely spaced grooves 46, i. e. indentations, on their undersurfaces. These are believed to have the eifect of stretching the exposed undersurfaces of said edge portions during plasticization to an to the inch. The depth of the grooves is .025 to .030 of an inch.
Although the methodjust outlined is particularly advantageous for maintaining a plastic sheet in drumtight condition over the inset central portion) only of a scale, it alsocan be employed "for covering the entire surface of such a-scale not provided with bolsters.
The cover preferably is placed on the inset central portion when the cover is in a semi-plastic condition. The lateral edges of the cover then can be readily folded over the inset edges 40a of the central portion, and suitable .plasticizing heat and pressure applied to the folds and,subsequently, against the undersurface of the inturne'd marginal edge-portions,the latterheat and pressure being applied for-plasticization by a shaped die which forms grooves in said-edge portions while pressing the edge portions firmly against the back-of the-scale.
The scale and cover are formed in a manner well known to the art, such for instance as is described in'detail in'Patent No. 2,284,833.
The cover is rendered semi-plastic in any suit-- able manner, a satisfactory method being "illus- 'tratedand described in said Letters-Patent No.
2,284,833. After the cover has been rendered semi-plastic and the scale optionallypreheated as mentioned in the said Letters Patent, the cover and scale are placed in an assembly machine where the marginal-edge portions of the cover are folded over the'lateral edges of the scale and thereafter the grooves are impressed-during plasticization in the exposed surfaces of said marginal edge portions.
An apparatus 50 constructed in accordance with the present invention for carrying out the aforesaid 'method is shown in Figs. 6, 7 and 8.
Said apparatus includes a support 52 on which 'ablock 54 is rigidly secured. The block has a substantially oblong vertical hole 56 extending centrally therethrough, the length'and -width of the hole being slightly inexcess of the length and width of'the elongated central inset'portion 40 of the scale. The upper surface'5B of the block slopes "downwardly from both ends toward the hole 56. Said sloping surfaces are flat and support folding plates 66 which are captivelysecured for movement toward and away from the hole by guide plates 62 that permit the inner edges 64 of the folding plates to be moved from an outermost position, shown in Fig. 8, to an innermost position, shown in Fig. 10.
A forming die 66 is yieldably'resiliently mounted on the support "52 for vertical reciprocation withinthe oblong hole 56. More particularly'the the folding plates.
scale. Accordingly the operative, surface of said die constitutes a transversely concave elongated groove.
In the idle position of the machine (see Fig. 8) the forming die is in its uppermost position, defined by abutment of the pistons 10 against the upper endsof the cylinders 12. In said position the operative surface of the forming die is slight- 1y below the upper corners of the inner edges 64 of Inasmuch as in said idle position of the machine the. folding plates project over the hole 56, the upper corners of the forming die are cut away as at 16 to prevent interference between the forming die and said plates.
To retain a scale in a predetermined position at the beginning of and throughout the assembly operation, the apparatus 50 includes a pair of stanchions 18 on opposite sides of the block 54 adjacent the ends of the hole 56. Vertical guide slots 80 formed in the stanchionsin registry with the ends of the hole 56 match the contours of the peripheries of the bolsters for a scale which isto be assembled with a .cover. The stanchions and slots extend above the hole 56.
To retain a cover in a certain predetermined position with respect to a scale at the beginning of an assembly operation, the inner edges of the guide plates 62 are formed with broad shallow notches 82 that mutually define an opening for receiving the cover. It will be observed that this permits the edges of the cover to rest on the folding plates 60, as shown in Fig. 8. Thereafter the scale is placed on top of the cover.
The apparatus further includes means to force the scale and cover against the forming die. Said means constitutes a ram 84 mounted for vertical. reciprocation in guides 86 and actuated by a lever 88. The ram carries a pair of vertical cylinders 89 in each of which a piston 90 is biased slidably downwardly by a spring 92. The pistons support rods 93 whose lower ends have secured thereto a forming punch 94 thebottom surface of which is shaped to match the configuration of the back of a handle unit. A plurality of pins 99 project from said bottom surface, said pins being biased downwardly by springs 98. The springs 98 are stronger than the springs 92 and the springs 92 are stronger than the springs 14.
The apparatus 50 also includes suitable means to actuate the folding plates, said means including, for example, a pair of cam rods I00 carried by the ram and engaging cam slots I02 adjacent the outer edges of the folding plates.
Means such as electrically energizable heaters I04 is provided to maintain the folding plates 69 at a temperature sufficiently high to plasticize the material of the cover when pressure is applied. In addition other heating means such as another electric heater I06 is provided to maintain the forming punch 94 at about the same temperature.
In practising the method of the present invention the scale may be preheated to about the plasticizing temperature for the material of the cover 34, e. g. 200 to 300 Fahrenheit where the cover is cellulose acetate. Also the cover may be preheated to a temperature below its plasticizing temperature, e. g. a temperature of from about 100 to 120 Fahrenheit for the same material. The cover then is laid in the opening definedby the notches 82 and the scale placed on the cover with the bolsters riding in the guide slots 80. [Next the apparatus is set into operation by depressing the lever 88.
The ram 84 descends and first causes the pins -vide the stags 96 to engage the center of the back surface of the inset arched portion 40 of the scale. Initially this forces the scale down against the cover to bow the latter and then jointly presses the cover and scale down between the inner edges of the folding plate 60 until the cover is seated on the forming die 66. Thereafter the cover, scale and forming die move downwardly as a unit until the forming die abuts a plate I08 extending across the bottom of the hole 56 as shown in Fig. 9. This position is reached just before cam portions H0 of the rods ms engage rollers H2 in the slots I02.
Upon further downward movement of the ram, the cam portions engage said rollers M2 to force the heated forced plates inwardly over the forming die as shown in Fig. 10. The action of said heated plates in folding over the marginal edge portions of the cover and plasticizing the folds is described in detail in Letters Patent No. 2,- 284,833. Subsequent downward movement of the run causes the cam portions III] to move the folding plates outwardly and expose the back surface of the handle unit in which the marginal edge portions of the cover now are tucked over the back of the scale (Fig. 11)
It will be observed that as the folding plates move in and out the ram moves downward but the position of the pins 96 does not change, the difference in movement being taken up by compression of the springs 92.
Near the end of the downstroke of the ram the bottoms of the cylinders 89 abut the top of the forming punch 94 and force the same downwardly against the action of the spring 98 (Fig. 12) so that the bottom surface of the heated forming punch presses against the back of the assembled handle unit to plasticize the same without, however, plasticizing the portion of the cover overlying the front of the scale. Said bottom surface of the forming punch includes a series of ribs or projections 114 (Fig. 13) which are in vertical registry with and engage the tucked in marginal edge portions of the cover to form grooves 48 therein during plasticization.
On the return stroke of the ram first the forming punch will back oif to the position of Fig.11, then the forming plates will move in and out and subsequently the forming punch will be lifted to its raised position (Fig. 8) ready for the start of a new cycle.
A modified form of the invention is illustrated in Figs. 14-21. The handle unit 30 and apparatus 50' of this modification is substantially similar to the unit 30 and apparatus 50 first described herein and, hence, similar parts will be denoted by the same reference numerals primed. The basic difference between the two handle units is that the scale 32' of the handle unit 30 has an inset central portion 40 whose external (convex) surface includes a large number of longitudinally elongated grooves H6 known as stags. The cover 34 has a matching configuration when assembled on the scale (see Figs. 17 and 18). To obtain its illustrated shape, the scale 32' at or subsequent to the blanking thereof is pressed or stamped to pro- V H6. It will be observed that these stags which constitute elongated grooves on the outer surface of the inset central portion 40' form corresponding projections H8 on the back of the scale. 7
The forming die 66" of the apparatus 50' is heated, as by a resistance cartridge H9, and has its operative surface provided with stag pro- 7 iectibns [20 matching the stag rooves H6 whereby when the cover and scale are forced against the forming die the cover will" be plasticized and shaped to match the outer surface of the inset central portion of said scale, thereby forming the stag grooves I22 in the external surface of the cover. These grooves have been found to improve the maintenance of intimate contact between the cover and scale and also to inhibit longitudinal shrinkage of the cover, despite the fact that the cover must be heated to the point of plastici'zation in order to make its contour conform to that of the stagged scale.
Theforming punch, instead of being provided with transverse ribs lid, is fashioned with stag grooves I24 which match the stag projections I I8 on the back off the scale adjacent the lateral edges thereof. Thus when the heatedforming punch descends it will cause the folded over marginal edge portions of the cover to conform during plasticization to the configuration of the back of the inset central portionof the scale (see Fig. 16), thereby fashioning grooves on the back surface of the tucked in marginal portions which cause said inturned cover portions to maintain intimate contact with the back of the scale.
It thus will be seen that there are provided handle units and methods and apparatuses for making the same which achieve all the objects of the invention and are well adapted to meet the conditions of practicaluse.
As various possible embodiments might be made of the above invention,- and as various changes might be made in the embodiments above set forth, it is to be understood that all matter herein described, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.
Having thus described the invention, there is claimed as new and desired to be secured by Letters Patent:
1. A knife handle unit comprising a thin selff'orm-maintaining sheet metal scale and a thin pastic cover, said cover having a front portion overlying the front of the scale and marginal edge portions lying against the back of the scale, said front portion and said marginal edge portions being joined by folds lying against the edges of the scale, said edge' portions having grooves on the external back surfaces thereof whereby said edge portions'are kept in intimate contact with the back of the scale and the folds in intimatecontact with the edges of the scale.
2. A knife handle unit comprising an outwardly convex thin self-form-maintain-ing sheet metal scale and a thin plastic cover, said cover having afront portion overlying the front of the scale and marginal edge portions lying against the back of the scale, said front portion and said marginal edge portions being joined by folds lying against the edges of the scale, said scale having stag indentations on its convex surface and stag pro-' jections on its concave surface, the contour of said cover, including the marginal edge portions, matching thecontour of the underlying surface of the scale. 7
3. A knife handle unit as set forth in claim 1 wherein the grooves extend transversely of the scale and are closely spaced.
4. A knife handle unit as set forth in claim 1 wherein the grooves are closely spaced-and elongated and the longitudinalaxes thereof have a substantial transverse component.
. In" an apparatus of the character described 8 ror'manufacturing a; knife handl'e' unit including'a plastic cover which 'iss'elf-h'eld'toa scale: a form'* ing die for supporting a cover with a scale thereon, resilientmeans to support the die for movement' between an idle and an operative position, a pair'of heated folding'plat'es, means to mount said plates for movement over the edges of the scale when the die'is' in operative position so as to fold the marginal edge portions of the cover around the edge of the scale and plasticize said cover at the folds, a forming punch, means to mount said punch for movement toward and away from the die, said punch having an operative surface, a spring-loaded pin extending away from said 013- erative surface, s'aidpin being disposed to engage the scale and to press the die through the cover so as to move the die fromits idle to its operative position upon movement of the punch toward the die, a reciprocable member, resilient means interconnecting said member" and the punch, cam meansinterconnecting said member and the folding' plates for moving the folding plates from idle to operative position and back to idle position while the pin extends from the operative surface of the punch and isholding the die in operative position, said memb'er being arranged to move the operative surface of the punch into contact with the back surfaces of thefol'dedmarginal edge por'-' tions after the folding means has been restored to idle position, and: means to heat said punch, the operative surface of saidpunchhaving projections for forming grooves in the back surfaces of the folded marginal edge portions of the cover.
6. In a method. for manufacturing a knife handle unit including a plastic cover which is self -held' to a scale andin'which method the marginal edge portions of the cover are folded around the edges of thesealeand plasticized at the folds:
that improvement including the steps of heating and pressing the back surfaces of th'e'foldedmarginal edge portions againstthe back surface of the scale after the same" has been folded so as to plastici ze; said portions and force the same into intimate contact with the back of the scale, and forming grooves in saidback surfaces-during plasticization of said portions.
'7. In a method for manufacturing a knife handle unitincludinga plastic cover which is self-held to a scale and in which method the marginal edge portions of the cover are folded around the'edgesof the" scale and plasticized at the folds: that improvement including the steps of heating and ressing; the back surfaces of the folded marginal edge portions against the back surface ofthe scale after the same has been folded so as to pla'stici'zesaidportions andfoi-cethe same into intimate contact with-the back of the scale, and simultaneously forming grooves in said back surfaces as said portions are thus plasticiz'ed.
References Cited in the file of this" patent UNITED STATES PATENTS.
ml er Name t 892,702 yman' July'7, 1908 1,186,693 Siggins June 13, 1916 1,524,449 Myers Jan. 27, 1925 1,903,? Maier' May 16; 1933 2,170,537 Mirandoet a1 Aug. 22', 1939 2,210,509 Strauch Aug. 6, 1940 2,268,058 Paonntomo Dec. 30, 1941 2,234,333 Mirandc- June 2, 1942* 2,285,635 Vossler' June 9, 1942 2,302,379 Reec'eet a1 Nov. 17', 1-942 2,3235862' Zimmeret al-f July 6; 1943