US2457644A - Needle grinder - Google Patents

Description

Dec. 28, 1948. F. CROSSMAN ET AL 2,457,644

NEEDLE GRINDER Filed Jan. 29, 1945 2, Sheets-$heet 2 4/ INVENTORS FRED (t ss 1AM me; A ourlmm'v 6:025: J3 Fun "wan, guy/m Patented Dec. 28 1948 NEEDLE GRINDER Fred Crossman and Earl A. Southam, Cleveland,

and George J. Ruhl, Shaker Heights, Ohio, assignorsto The Lindsay Wire Weaving Company, ClevelamhOhio, a corporation of Ohio Application January 29, 1945, Serial No. 5750471 5 Claims.

This invention relates to: apparatus for grinding the points on needles used in: diamond die drilling machines. The needles are. intended to drill holes varying from four ten-thousandths of an inch to five thousandths of an inch in. diam eter;

One of the difiiculties encountered in. drillin fine holes in diamonds has been the necessity for maintaininga sharp point on the needles. and at the same time maintaining the desired angle of taper at the Work engaging end thereof. It is important, however, to maintain the desired angle of taper in order to assure the desired shape of bore in the diamond die. Heretofore the practice has been to remove the needle frequently ing operation, but was objectionable in that there was danger in bending the point by frequent remcval and replacement of the needle. The points of such needles are so fine that if one be struck against any part of the machine the point may thus be bent and thereby rendered useless with-' out another grinding operation.

An object of the present invention is to construct. a grinding or dressing apparatus, which will enable the point of a needleto be dressed while it remains in the machine. In addition, the invention contemplates a construction wherein the angle of taper to be ground on the point of the needle may be accurately controlled by the operator, and wherein the pressure appliedon the rinding member against the needle may likewise be under control of the operator.

We have shown our invention in connection with a diamond die drilling machine wherein I shows the front view of the machine; Fig. 2 is a top plan view thereof; Fig. 3 is an end view of the machine; Fig. 4 is a section taken on the line 4f'-4 of Fig. 3; Fig. 5 is a section taken on the line 5 5 in Fig. 2; Fig. 6 is a section taken on the line 6-5 in Fig. 4; and Fig. 7 is a view showing the work table having a diamond die mounted in its holder and supported on the table.

1 ,The diamond die drilling machines which we have illustrated in our drawings has a frame which includes spaced horizontal plates "II and I2. A work table. 13 is disposed above the mounted upon aspindlel8 which is journalledin the plates Hand I2 and which is. adapted to be rotated from a source of power (not shown) by a belt l9 which extends around a pulley 20 on the spindle l8.

The needle which is adapted to drill a hole in the diamond i5 is indicated at 25 as being-car'- ried by and depending from a holder 26 which is in the formof a spindle and extends above and below a driving mechanism indicated in general at H. The drive mechanism may be rotated by means of a belt 28 which is connected to any suitable source of power, such as an electric motor, not shown.

During the die drilling operation the needle is adapted to be intermittently raised and lowered and for such purpose the spindle is shown as having a collar 29 which provides a shoulder against which. the forked end of the lever 30'may engage, the lifting being accomplished by the tilting oithe lever about the pivot 3|. The tilting action may be effected by means of spaced cams 32 on a wheel 33 which is journalled on a shaft 34 and is adapted'to be rotated by a belt 35 from any suitable source; of power. The shaft 34 may be journalled in brackets 36 which are attached to a plate 3 The last named plate is rigid with the housing for the drive mechanism 21 which in turn maybe ailixed by a plate 38 to the frame The needle dressing mechanism embodying the present invention. includes an abrasive member 49 shown in the form of a disc or wheel which is aiiixed to a shaft M that is journalled in bearings 42 and 43. The shaft and abrasive member are so. supported that the member may be adjusted vertically with respect to the needle, and may also be adjusted angularly with respect to the needle, and may be moved toward and away from the needle under pr ssure exerted by the operator. The angular adjustment of the. grinding member controlstho, taper to .beimparted to the end. of

- plate H3.

idly fastened thereto a pair of depending arms- 48 which are slotted at 49 to receive pins 55 that The grinding member is then adjusted vertically project laterally from the bearing 43 and operate to support the bearing for vertical movement with reference to the arms 48. The vertical movement may be controlled by means of a thumb screw which'is in threaded engagement with the bar i'l and which is adapted to engage the upper surface of the bearing 63. A spring 52 bears against the under-surface of the bearing and also against a tie plate 53 which connects the lower ends of the arms 48. Thus, by adjusting the screw 5| ,the shaft 4| iscaused to swing r about the pivot Q5 and thereby to varytheangle of the abrasive member ll) with relation to the needle.

It is desirable to so mount theabrasive member ll that it may be moved toward and from the needle while the grinding face thereof is main-- tained parallel to its original position. This we accomplished by pivotally supporting the cross bar iluponparallel links- 55 and55 by studs 5? and'58.. The other ends of the links are pivotally connected at 59 andellto a cross bar (ii that is adapted to be adjusted vertically with respect to the frame plate ID". The means for obtaining the'vertical adjustment of the cross 'bar' 6!, and thereby obtaining vertical adjustment of the shaft ll and its associated grinding by proper manipulation of the thumb screw 65 and is adjusted angularly by manipulation of the set screw 5|. Thereupon the grinding member 40 is rotated under the influence of the driving belt 16 which extends around the pulley '11 that is afiixed to the shaft 4| and the grinding member together with its associated supporting mechanism is moved as a unit towards the needle until the forward movement thereof is arrested by the stop mechanism 10 and 12. By carefully adjusting the set screws 65, 5| and 10, the pressure exerted against the needle can be accurately controlled, and the angle of grind can likewise be adequately varied to suit the particular requirement of the work required to beperformed by the needle. The forward and back ward movement of the dressing member may be accomplished by light finger pressure against any part, of the shaft supporting mechanism;

We have found that our invention not only has obviated thenecessity for frequent removal of the needlefrom' the drilling machine for dressmember 40, preferably comprises an adjusting-1t screw 65 which is adapted to extend through: a

threaded opening in a cross bar 66 and to engage at its lower end the upper surface of the cross bar 6!. The bar 66 is rigidly held with respect to the members 59 and 50 by nuts 61 and the bars,

65 is held in engagement with the lower end of the thumb screw 65 by springs 68 which surround the members 55 and .60 respectively and are disposed between the links 55 and 55 and the To limit the movement of toward and from the needle, we have shown a stop device in the form of a thumb screw 10 which'is in threaded engagement with a passageing purposes, but that the time required for the grinding operation has been greatly reduced, and that the shape of the needle can be accurately controlled to an extremely fine degree.

We claim: i

"1. A device'of the character described, .com-

prising a grinding member, a shaft therefor,

means for pivotally mounting the shaft-while,

- for supporting the first-mentioned means to effect a movement of the grinding member'toward and from the work, and second-named means including a device for shifting the first-mentioned means and the grinding member as 'a' unit with reference to the work. I Y

2. In a, device of the character described, the

combination of a frame, a bar mounted for movethe grinding member I way in a block 1! and which may be afiixed to' thearm do as shown in Figs. 1 and 6. The leading endof the thumb screw is adapted to engage a part of the frame which in Fig. 1 is illustrated as an angle plate '52 and is fastened to the underside of the plate 38. Thus, by adjusting the axial position of the screw with reference to the block l l, the movement of the grinding member toward the needle may be accurately limited so as to control effectively the extent to which the needle will be ground. E l 1 In using the grinding device embodied in the present invention, we prefer to adjust the position of the lever 30 by turning the thumb screw F5 which controls the vertical position of the pivotal so as to have a clearance between the" forked end of the lever'fifl and the collar 29. At

such time the needle is supported by the driving mechanism which is operated to effect rotation of the needle but without imparting an interment toward and from the frame, a pair of links pivotally connected to the bar adjacent one'end of the links, a second bar pivotally connected to the links adjacent the other'end'thereof, a'grinding member, a driving shaft therefor, and means carried by the second bar for journaling the shaft and for supporting it for pivotal movement with respect to the second bar. A f 1 v 3. In a device for grinding a drill in a drill spindle in operative position relative toa Work table, the combination of a support adapted to be adjustably positioned at the side o f'the space between the drill spindle and table, a pair of links pivotally connected at one end; to said adjustable support, a member pivoted to the other 'endsbf :saidllinks, a bearing pivotally carried by said member, a shaft journaled in said bearingigrinding wheel operated by said shaft and adapted to engage a drill in the spindle, and means for tipping said shaft and holding it in selected posi- ,tion to present the grinding wheel atthedesired angle to the drill, I V

4. The combination with a diamond meanning machine having means for supporting andromittent or reciprocating motion thereto. Itis' to be understood that the needle is first lifted andthat the'diamond die is removed from the work table I3 and that the n'eedleis. then allowed to'drop to its normal position as shown in Figxl.

tating the needle and a table aligned-therewith of a grinding device comprising a grinding member mounted for rotation and disposed at one side of the needle between the shank of the needle and the table, means for supporting the grinding axis of the needle, said supporting means includ- 5 ing a device for adjusting the grinding member axially of the needle and angularly with respect to the needle, and means for limiting movement of the member toward the needle.

5. A device of the character described comprising in combination, a frame, a grinding member, a carrier therefor, an adjusting member resiliently supported on the frame, means for supporting the carrier on said adjusting member and adapted to permit movement of the grinding 10 other means for varying the angle of the grinding member with respect to the work.

FRED CROSSMAN. EARL A. SOUTHAM. GEORGE J. RUI-IL REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 398,741 Morrison et a1 Feb. 26, 1889 1,394,704 Barnhart Oct. 25, 1921 1,548,105 Soderberg Aug. 4, 1925 2,398,251 Robbins Apr. 9, 1946

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