US2000239A - Slitting fixture for piston rings - Google Patents

Description

May 7, 1935. J. c. LINN SLITTING FIXTURE F OR PISTON RINGS 2 sheets-sheet 1 Filed Oct. 11, 1929 0W7? Pb C. Lira, 8% KW 4 52 Ma /MM May 7, 1935.

J. C. LINN SLITTING FIXTURE FOR PISTON RINGS Filed Oct. 11. 1929 2 Sheets-Sheet 2 NN rE MN MN I EU/QWT fisz v/z 0'. L ijuz W,W, aw wmwa Patented May 7, 1935 Q 1 I I 2.000.239 SIJTTING FOR PISTON RINGS I Joseph C. Hnn, Hagerstown, Ind.,' assignor to y The Perfect Circle Company, Hagerstown, Ind, a corporation of Indiana Application October 11, 1929, Serial No. 398,835

Claims. (CI. 9059) I.

My invention relates to a slitting fixture for Fig. 3 .is a plan view of the fixtureas viewed piston rings and more particularly to a device in Fig. 1; of this kind for holding a previously slit ring Fig. 4 is a sectional view similar to that shown during a succeeding slitting operation.- in Fig- 2, but showing several parts of the fix- 5 The principal object of my invention is to ture in retracted positions and in readiness for 5 devise a fixture of the foregoing character the receipt of a piston'ring; which is constructed and arranged to compress Fi 5 i a perspective view of a slitted piston a ring sufiiciently to close the preliminary slit r S c s m y be a ed y my fixture. by applying a constraining pressure to the major The numeral It represents a bedplate which portion of the length of the outer, circumferensupports an angle bracket ll whose base I! is 10: tial surface of the ring, while positively holding ur d to e dplate It by bolts IS. The the ring in the region of the slit and in direc-' upstanding portion of the bracket ll constitutes tions transverse to and in the plane of the ring a face plate I, having a working face If: formed against the pressure exerted by the cutting saw. on the front, or left edge of the bracket as A further object is to devise a fixture of viewed in Fig. 2. The bracket H is slotted as 5 the character described in which the pressure at It downwardly from the upper edge thereof in the region of the slit can be quickly apalong a central, vertical line, the separated plied and released, and in which the pressure is portions thus formed being strengthened by so directed as to substantially wedge the indiea a dly e end g ribs l1 disposed on oppoouted portions of the ring against the fixture to site sides of the slot l6 and extending down- 20 positively seat and hold the same. wardly along t e a Side O the P te N o My invention is directed t d providing the base l2 thereof. Extending forwardly from fixture for holding a single and previously slitthe face 5, 01 toward the left as viewed in Fi ted piston ring for presentation to a cutting a shoulder is having a gth Substantially aw for effecting either a finished slit, or genequal to the width of the plate II. Guide plates 25 erally, a succeeding slit of some kind. It comare secured to the Opp n of e Plate prehends a fixture in which a ring is manually y cap ews and said guide plates extend placed in position, although it could be mounted from e owe ed e o th ac p te It upwa dby any desired mechanical arrangement without 1y t t as of th s t 6 sai ui p at s esaflecting the central thought involved, and; in tablishing with the shoulder l8 and the face I 5 30 which the tendency of the ring to move in the a recess for a purpose presently explained. comparatively, flexible region, adjacent the slit, A wedge block 2| is slidably mounted on the is completely prevented by applying a suitable shoulder l8 and is provided with an inclined, pressure in those localities, so disposed as to Upper edge 21 d a o ated S ot 23 which immobinze t indicated portions of t e ring is parallel to the lower edge of the block. This 35 in all directions. The clamping member which block S eta n d against lateral movement by effects the foregoing pressure is actuated means of a cap screw 2! which extends through through a very limited range of movement, from the Slot 23 threaded g ment With the retracted t gripping position, which serves t face plate I and endwlse ad ustment of said decrease the time required for positioning the block, for a purpose e ina e explamed is ring effected by means of adlustlng screws 25 which These and further objects of my invention will are thIeaFIed through the gulde Plates and be set forth in the following specification, refer- 33 3522 1 3 g i g gg if i g zza ence bemg had to the accolppamimg qmwmgs desired adjustment of the block 2! toward the and the novel means by which sald ob ects are left while the left Screw as viewed in said ill be definitely pointed out in the effictuated w figure, will effect the desired ad ustnlent 1n the e opposite direction, after which both of said In the drawi screws may be locked in the indicated positions Figure 1 is a front elevation of my lmproved by means f lock nuts It 50 slitting fixture, showing a piston ring'positioned An adjustable Presser block 21 is disposed erein a d a cuttin saw in operativ i n above the wedge block 2| and is shaped along thereto; its lower edge with an inclined surface 2! for Fig. 2 is a section along the line 2-4 in Fig. 1 engagement with the inclined surface 22 on the as looking in the direction of the arrows; block 2|. The block 21 is provided with a pair UNITED [STATES PATENT. OFFICE of spaced, vertically elongated slots 29 through which extend the threaded shanks of cap screws 30 for engagement with the face plate |4. During the vertical adjustment of the block 21, the same is guided by the plate l9, as shown clearly in Fig. 1. The block 21 is bored to form a parti-circular recess 3| whichfaces upwardly, as viewed in Fig. l, and which is defined by a parti-annular base 32 and a peripheral shoulder 33, normally disposed with reference to eachv other, the remaining portion of the recess 3| within the annular base 32 being further bored to a greater depth for purposes of clearance. A pin 35 is fixed in the block 21 midway of the ends thereof and within the margin of the recess 3| for a purpose hereinafter explained.

A block 36 is fixedly secured to the upper portion of the plate I4 by means of cap screws 31 and extends downwardly toward the base of the slot l6. A slot 38 is cut upwardly from the lower edge of the block 36 and so disposed as to be in alignment with the slot "5 when the block 36 is secured in position. The block 36 is further slotted at 39 downwardly from the upper edge thereof in a direction which is inclined to the front face of said block, as shown clearly in Fig. 3, such slot being generally aligned within the limitations of its disposition with the slot H5. The purpose of the slot 39 is to permit the application of a cutting saw 40 to the piston ring 3# as hereinafter described. The block 36 is likewise bored to provide a parti-circular recess 4| which faces downwardly toward and is intended as a complementary recess to the recess 3!. The recess 4| is defined by a parti-annular base 42 and a peripheral shoulder 43 normally disposed with reference to each other, the remaining portion of the recess 4| within the annular base 42 being further bored to a greater depth for purpose of clearance. A pin, or cam member 44 is fixed in the block 36 above and in alignment-with the vertical, median line of the slot 38. The lower side of the block 36 is cut inwardly from the opposite ends thereof, as is also the face plate l4 immediately above the guide plate H, to form a pair of slots 63 with each other and with the upper edge of the block 21. These slots extend inward sufficiently to expose portions of the ring 34 in order to permit its easy withdrawal by means. of the fingers or a special tool.

The face plate I4 is drilled as at 45 across the slot I6 for the reception of a pin 46 which pivotally supports a lever 41. One end of said lever extends to the rear of the plate l4 and is pivotally connected by means of a pin 46 to one end of a link 49, the other end of said link extending downwardly through suitable holes in the base l2 and bedplate III for connection to and actuation by mechanism of .a suitable nature, such as a lever, pedal, and the like. The opposite end of the lever 41 extends forwardly of the front face of the block 36 and is provided with a curved nose 50 which extends generally in an upward direction and the rear side of said nose is further defined by a reentrant curve 5|.

The nose 50 projects loosely through an elongated slot 52 which is formed within the marginal. edges of a clamping member 53 having a generally rectangular shape. The upper end of the slot 52 is inclined as at 54 upwardly and toward the left from the inner face of the member 53 and said inclined surface is normally in contact with the nose 50, both in gripping and retracted positions. The upper end of the member 53 is bifurcated to provide a pair of arms 55 which are notched inwardly from the inner face of said member to provide a pair of normally disposed faces 56 and 51 intended for contact with separated portions of a flat face of the ring and also the inner, curved face thereof. A portion of the inner face of the member 53, immediately below the aforesaid notches, is offset as at 58 and said offset portion is connected to the remaining area of the inner face of said member by means of an inclined, or cam, surface 59. The lower end of the member 53 is provided with an offset shoulder 6| whose face contacts with the inner portion of the recess 3|, operating as a spacing element.

In using the slitting fixture, the block 21 will be adjusted vertically to such a position, dependent upon the size of the ring to be slitted, that when the ring is in position in the fixture, the slit 62 thereof will be substantially closed by the constraining pressure exercised by the peripheral shoulders of the recesses 3| and 4|. The rings may be placed within the holder constituted by the blocks 21 and 36 either manually, or by any suitable type of mechanical contrivance. During this initial positioning of the ring, the lever 41 and the clamping member 53 will occupy the positions shown in Fig. 4 and the manner in which said member achieves the position shown will be presently described.

The ring 34 having been positioned in the aforesaid holder with the slit 62 thereof properly disposed with reference to the inclined slot 39, the link 49 will be actuated downwardly to cause an upward movement of the opposite end of the lever 41 with a consequent lifting of the member 53; by reason of thecontact between the nose 50 and inclined surface 54, to the position shown in Fig. 1. In this position, the arms 55 will be disposed on opposite sides of the slot 39 and the notched faces 56 and 57 of each arm will bear against certain portions of the outer, fiat face of the ring and the curved, inner surface, respectively. It will be observed that, by reason of the inclined disposition of the surface 54 and the direction in which the nose 5!! applies pressure to said surface, the notched faces 56 and 51 will be substantially wedged against the contacted portions of the ring to thereby adequately seat the latter within the holder and absolutely prevent any movement thereof adjacent the slit 62. The cutting saw 40 will then be moved toward the fixture, or vice versa as determined by operative conditions, and the slitting operation effected.

After the slit has been cut, the link 49 will be moved upwardly to cause a downward movement of the nose end of the lever 41 and consequently a release of pressure against the inclined surface 54. The clamping member 53' being loosely mounted on the nose end of the lever 41 will thereupon begin to move downwardly from the position shown in Fig. 2, but it is important to control this downward movement so that said member will finally reach the fully'retracted position, shown in Fig. 5. This control is effected by means of the head of the pin 44 which engages with the inclined, or cam surface 59 on the inner face of the member 53, during its downward movement, to thereupon positively throw the upper end of said member outwardly from the face plate, this result being facilitated by the slightly greater thickness which the member 53 has at its upper end,

thus creating a slight overhang in this portion of the member. The nose 50 continues to move downwardly and is closely followed by the upper end of the member 53 after actuation by the pin 44, until the lower end of said member engages with the stop pin 35, whereupon further downward movement of said member is arrested and it is retained in the position shown in Fig. with the inclined surface 54 resting on the curved nose 50 and the member as a whole inclining outwardly from the face of the holder.

The member 53. both in its gripping and in its retracted positions is retained wholly within the portion of the holder which is occupied by the piston ring. Accordingly, only short movements are necessary to place said member in either of the indicated positions, so that the movable part of the fixture may be actuated with ease and precision. Due to its looseengagement with the lever 41, the member 53 is at all times in a position for quick removal in the event of any breakage, while the style of clamping member illustrated affords a convenient means of adequately holding a previously slit piston ring in localities adjacent to the slit, which portions are the most flexible of the ring and consequently more subject to movement under the pressure exerted by the cutting saw.

While I have shown one set of elements and combinations thereof for effectuating my improved slitting fixture, it will be understood that the same is intended for purposes, of illustration only and in nowise to restrict my device to the exact forms and structures shown, for many changes may be made therein without departing from the spirit of my invention. v

I claim: 1

1. A slitting fixture for a piston ring comprising in combination, a holder for receiving the ring, a lever pivoted on said fixture, a clamping member having a cam surface adjacent the upper end thereof facing said holder and loosely straddling said lever for actuation thereby when moved in one direction to grip said ring on 0pposite sides of a cutter during the slitting operation, and a pin projecting from the upper face of said holder, said lever permitting the retraction of said member under the action of gravity when moved in the opposite direction, and said pin engaging said cam surface during the retracting movement of said member to throw the upper portion thereof away from the plane of the holder.

2. A slitting fixture for a piston ring comprising in combination, a holder for receiving the ring, a lever pivoted on said fixture, a clamping member having a cam surface adjacent the upper end thereof facing said holder and loosely straddling said lever for actuation thereby when moved in one direction to grip said ring on opposite sides of a cutter during the slitting operation, a pin projecting from the upper face of said holder, said lever permitting the retraction of said member under the action of gravity when moved in the opposite direction, and said pin engaging said cam surface during the retracting movement of said member to throw the upper portion thereof away from the plane of the holder, and a stop for limiting the downward movement of said member during its retraction.

3. A slitting fixture for a piston ring comprising in combination, a holder for receiving the ring, a lever pivoted on said fixture, a clamping member loosely carried by said lever, the actuation of said lever in one direction serving to grip said member against the ring on opposite sides of a cutter during the slitting operation, and the actuation of said lever in the opposite direction permitting the retraction of said member under the action of gravity, and means for throwing the ring engaging. end of said member away from the plane of the holder during the retracting movement of said member.

4. A slitting fixture for a piston ring comprising in combination, a holder for receiving the ring, a clamping member located within the periphery of the ring for gripping the'same on opposite sides of a cutter during the slitting operation, a lever pivoted on said fixture and having an arm extending through the plane of said ring within the periphery thereof for controlling the movements of said member to g ip and releasing positions, and means for throwing the ring-engaging portion of said member away from the plane of the holder during the releasing movement of saidmember.

5. A slitting fixture for a piston ring comprising in combination, a holder for receiving the ring, a lever pivoted on said fixture, and a clamping member loosely carried by said lever, said member being located within the periphery of the ring with one end being adapted to grip the ring on opposite sides of a cutter during the slitting operation and the other end adapted to bear against the face of the holder, the actuation of said lever in one direction moving said member intogripping position and in the opposite direction permitting the releasing movement of said member under the action of gravity.

JOSEPH c. LINN.

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