US1920986A - Method of making combined abrasives and holders - Google Patents

Description

Aug. 8, 1933. M. c. HUTTO 1,920,986

METHOD OF MAKING COMBINED ABRASIVES AND HOLDERS Original Filed Dec. 11, 1926 Patented Au 8, 1933 UNITED STATES PATENT OFFICE METHOD OF MAKING COMBINED ABRASIVES AND HOLDERS Marsden 0. Butte, Detroit, Mich, assignor" to Hutto Engineering tion of Michigan Company, Inc., a Corporaher 4, 1932 This invention relates to a method of making combined abrasives and holders for grinders of internal and external cylindrical surfaces, and more particularly to a combined abrasive and holder of channel form. i

This application is a division of an application filed December 11, 1926, Serial No. 154,280, patented November 20, 1928, No. 1,692,661.

The object of the invention is to provide a combined holder and abrasive'in which the abrasive member, usually in the form of a natural or artificial stone is-supported ina channeled member or other supporting base having associated therewith members engaged by the adjusting means of the tool of which it forms a part so that the grinding face of the abrasive is mounted in the tool in a precise relationship with the adjusting device. In the tool with which i the combined abrasive and holder is used, as m shown herein, several abrasive members are mounted in a head intended to be reciprocated and rotated in the cylindrical aperture to be ground, and a feature of this invention relates more particularly to the holder of channel-like form in which the stone is secured by a selfhardeningmaterial, that is, flowed to place in a more or less liquid form. This material may be solder, babbitt or lead or a varnish, shellac or the like and, while the stone and holder are held in the relative final positions, the material for securing the stone in place is supplied thereto.

' A further feature of the invention is in the provision of a holder, preferably of sheet metal form, with which the'portions thereof adapted as for engagement with the adjusting device of the tool are riveted in place and the stone mounted therein by a solder or suitable material-in which the stone is "floated" or flowed in its final relationship with the holder and thus fixed in pre- 10 determined correct, technical position, as the material hardens.

As is hereinafter more fully described it is preferable, though not absolutely necessary, to

utilize a pair of pins each adjacent an end of the holder which, when in the tool, fit against opposing coned members that are adjustable toward or from each other and -in order that all the holders and the faces of all the abrasives shall lie in the same circle, it is essential that these cone contacting portions, which may be the pins as shown, shall be of a certain length relative to the grinding face of the stone. Thus the method of manufacture of the abrasive and its holder as hereinafter described seeks primrilytoinsureaccuracyinthemountingof 4 Claims. (01. 51-278) the stone so that the face which lies longitudinally of the tool shall normally be strictly parallel with the axis thereof- Stones used in cylinder grinders or lapping devices are usually made of compacted granular material such as carborundum or like abrasive and subsequently fired. Such stones usually vary in thickness throughout their length and therefore require dressing after the stone has been mounted in its holder.

A feature of this invention is in providing a holder and a method of mounting the stone therein which insures parallelism of the grinding face of the stone with the axis of the tool in which it is to be used irrespective of variations in thickness of the stone. Thus, the surface of the stone is normally exactly parallel with the axis of rotation of the grinding head or body. d

An object of this invention therefore is to provide a holder and a stone in which the holder and the stone are held in the desired final relationship and a self-hardening material, flowed between the members whereby they automatically become fixed in the necessary relationship and the finishing of the stone subsequent to mounting is dispensed with inasmuch as the major inaccuracies are compensated for by the self-hardening material.

These objects and the several novel features of the inventionare hereinafter more fully described and claimed, and the preferred form of an abrasive and its carrier or holder embodying this invention are shown in the accompanying drawing in which- Figure 1 is a longitudinal section of a tool showing the improved abrasive and itsholder mounted therein in accordance with this method.

Figure 2 is a perspective view of the finished holder and stone. 95

Figure 3 is a cross section, taken on line 3-3 of Fig. 2.

Figure 4 is a cross section of the holder and the stone indicating the method of securing the stone in place therein. 10o

Figuresfi and 6 are vertical longitudinal sections, on a reduced scale, taken on the correspondingly numbered lines inFig. 4, the selfhardening material being shown between the supporting base and the stone. corresponding to 105 Fig. 3.

In the invention herein described the holder consists of a supporting base having preferably the form of a shell or channeled member 1 which, as here shown, is preferably made of sheet metal no formed in a die and may be provided with an Y the holder and at right the holder and the face channel member being 7 This shell or channeled member 1 preferably has a U shape in cross section, as shown more. particularly in Fig. 3, and adjacent each end thereof is provided parallel pins 3 and 4 of like form projecting transverselyfrom the bottom 1a of angles thereto. These pins extend through apertures provided therefor in the body 5 of the tool to engage the respective cone members 6 and 7, the ends of the pins being tapered as at 8 to provide line contact with the respective cone member 5. These cones maybe adjusted as to'distance apart through the central adjusting screw 9 which is provided with a head 10 slotted for use of a screw driver.

By turning the adjusting screw to draw the cones together the faces of the abrasive members are moved to a greater radial distance from the axis of thetool and by the reverse turning of the screw the cones are retracted which is preferably accomplished through use of the spring members 9a and 10a which engage the lips 2 of each of the holders tending to contract the same. The two cones are yieldingly held apart by a spring 9b surrounding he screw 9 and bearing against the inner ends of these cones, as shown in Fig. 1

Subsequent to the formation of the channel member by means of a die as stated, the shouldered pins 3 and 4 have the reduced portions 11 thereof inserted through apertures provided adjacent each end of the shell or member 1 and the ends thereof peened over to fixedly secure the pins in place. Upon completion of this step the holder consists of the assembled channeled member and pins which are maintained in fixed relation with the shell but it is to be understood that the channel member may be provided with means for contacting the cones other than what is here termed pins".

This shell or channeled member 1 further has an aperture in the bottom 1a thereof midway between the cone contacting devices indicated at 110. in Fig. 4 and, to secure the stone 12 in place in the holder, I place mold 13 with the longitudinal edges 15a of its side flanges- 1b engaging gage faces 15 thereof, as indicated diagrammatically in Figs. In the form or mold, has previously been positioned the stone 12 which also lies with its longitudinal outer or working face 12a on a gage'face 14 of the form or mold which gage face 14 is exactly parallel with the gage faces 15 of the form. Due to the two side edges 15a of the finished to a definite the bottom 1a, the

length from the outer side of parallel with said face'l2a of the stone 12 is bottom. In the position of the parts shown in Fig. 4 the stone and the holder are therefore in a relationship in which they are to be fixed and to fix these parts together I introduce a solder or other self-hardening material 13a through the aperture 11a. The inaccuracies in stone thickness shown at 12b in Fig. 5 are thus disposed within 12a of the stone lies par- 15a and bottom of the angle to the axes of the allel with the side edges holder at exactly a right pins 3 and 4.

The assembled abrasive and'holder is then removed from the form and the pins 3 and 4, or

the cone contacting member of whatever form,"

are finished off for contact with the adjusting cones at an exact length face of the stone. If pins be utilized for the cone the holder in a form or 4 and .6.

measuring from the is herein shown, and due channeled member being finished off parallel with the bottom of the said member against which the shoulder of the pins engages, the axes of the pins are therefore, by this method, exactly at a right angle to the face of the stone. This accuracy in relationship of the stone and holder is necessary in order to secure precision inoperation of the tool and to function with the adjusting means so that the faces of all the stones cut the same circle.

The object of the invention therefore is secured by this method and character of device, that is, by this form of holder and method of making thereof, precision is attained and a grinding tool is secured that is accurate in the finishing of a piece of work and accurate possible adjustments.

I am aware of other-devices of this general character in which abrasive members are utilized many of which have stones and holders that are spring projected to working contact with the wall of the aperture being ground. This tool operates differently in that the holders are positively held in the adjusted position, and while the cone members 6 and '7 may traverse or move as a unit longitudinally of the tool body and thus permit the abrasive at one end to move toward the axis of the tool and at the other end outwardly therefrom the bit between the pins 6 and 7 and the body 5 being sufficiently loose for this purpose, yet as the tool in its operation is relieved from pressure through the grinding away of the surface operated on, the adjusting unit including the said cones takes the neutral position shown in Fig. 1 in which the faces of the stones lie ex-. actly parallel with the axis of the tool. This position being assumed at the completion of the grinding operation as the tool grinds free, the

contacting members, as to the edges 15a of the aperture being ground through reciprocation and rotation of the tool therein is of a uniform diameter throughout its length and with a straight wall. This accuracy in operation is secured by the character of the holder herein disclosed and the absorption of possible inaccuracies by means of a fluid medium 131: such as solder, babbitt, lead, varnish, shellac and the like flowed or floated in the space between the holder and the stone.

The combined abrasive provide a unit which may when the'latter is first put out or to replace worn units of like character'and has been devised primarily to avoid inaccuracies resulting from the user of the" tool attempting to replace a worn stone in holders as heretofore utilized in this art. To secure precision in operation of the tool, the grinding units should be replaced by new grinding units of thesame accuracy and precision as the worn grinding units.

By gaging the longitudinal and holder therefor face of the stone throughout all of its beusedinthetool and the longitudinal edges of the base or holder in parallelism on the mold the stone and holder may be secured together by self-hardening flowing material in a technically correct position relative to each other and the guide pins and the cooperating parts on the body of the tool regardless of any irregularities as shown at 12b, in Figs. 5 and 6, onthe back of the stone.

It will be noted that this combined abrasive and: holder permits of ready replacement of simi lar articles used in a cylinder grinder in that the stone supporting base provides means -for determining andmaintaining a desired relation of the abrading surface carried thereby to the 1,920,986 axis of revolution and traverse of the cylinder grinder, and that the grinding stone or abrasive is secured to the base by a'substantially rigid nel form for use in -tudinal movement of adherent material which the stone with reference its abrading surface in tion, so that on assemblyin the tool the working face ofthe stone occupies a technically correct working position.

I claim as my invention:-

1. The hereindescribed method of uniting an abrasive bar and a holder having a body of, chana tool which is adapted to grind cylindrical surfaces by a rotary and longithe tool, and which is promeans for determining and permanently positions to the base and with vided with adjusting maintaining a desired relation of the abrading surface carried thereby to the axis of revolution and traverse of the grinding tool; said method consisting in making said abrasive bar and said holder positioning said abrasive bar in the channel of said body so that upon assembly in the tool the working face of the bar occupies a technically correct working position; and flowing a liquid adherent material between said holder and bar and permitting said material to harden and rigidly connect said holder and bar and maintain the same in said predetermined relationship.

2. The herein described method of uniting an abrasive bar and a holder therefor having a body of channel form and parallel guide pins projecting transversely from the outer side of the holder and at right angles to the length of the same for use in a tool which is adapted to grind cylindrical surfaces by a rotary and longitudinal movement of the tool and which .is provided with adjusting means for determining and maintaining a desired relation of the abrasive bar to the axis of revolution and traverse of the grinding tool; said method consisting in making said abrasive bar and holder and pins positioning said body, bar, and pins relatively to one another so that the bar is arranged in the channel of the body and a space is formed between said determined posisaid body and bar and said pins are arranged at right angles to the working face of the bar, whereby upon assembly in the tool the working face of the bar occupies a technically correct working position relative to the axis of the tool and said pins properly engage said adjusting means; and flowing a self-hardening liquid material in said space so as to rigidly connect said body and bar and maintain them permanently in said predetermined relationship.

3. The hereindescribed method of uniting an abrasive bar and a holder which consists in making said abrasive bar and holder placing said holder on a gage; placing said bar on a gage and supporting the same in a technically correct position relative to said holder with a space between the bar and holder; and flowing a fluid self-hardening adhesive material into the space between said abrasive bar and holder and permanently securing said abrasive bar to said holder in a position in which the face of the abrasive bar occupies tion relatively to other parts of the tool when assembled therewith.

4. The hereindescrlbed method of uniting an abrasive bar and a holder having a body of channeled form and parallel guide pins projecting from the back of the body, consisting in making said abrasive bar and holder, placing the abrasive bar in a mold and engaging the face of the abrasive bar with gage faces in the mold, finishing the front edges of the channel walls so that the same are at right angles to the axes of said pins, placing said holder in a mold over said abrasive bar and engaging the front edges of the same with gage faces thereon so that holder and abrasive bar occupy a correct technical posi-- tion relative to one flowing a fluid self-hardening adherent material between said abrasive bar and body and securing the same together upon hardening said material.

MARSDEN C. HU'I'IO.

another and said pins; and

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