US2098506A - Buffing machine - Google Patents

Description

Nov. 9, 1937. G. E. MCLAUGHLIN ET AL BUFFING MACHINE Original Filed June 5, 1936 Patented Nov. 9, 1937 UNITED STATES PATENT OFFICE BUFFING MACHINE George E. McLaughlin, Broughton, Peabody,

Salem, and Winn E.

Mass., assignors to The Turner Tanning Machinery Company, Portland, Maine, a corporation of Maine 8 Claims.

This invention relates to machines for operating upon hides, skins and leather. While the invention is illustrated with reference to a machine for buffing leather surfaces it will be understood that the invention and various important features thereof may have other applications and uses.

This application is a division of a co-pending application Serial No. 83,718, filed June 5, 1936, in the names of George E. McLaughlin and Winn E. Broughton.

It is an object of the invention to improve various features of buffing machines and particularly to facilitate presentation of pieces of work to the bufling roll. It is a further object of the invention to provide improved means for preventing work pieces from being drawn into suction means provided to remove dust produced by the buffing operation, and at the-same time to facilitate the removal of dust from the bufiing roll.

To these ends, and in accordance with an important feature of the invention, there is provided a work supporting roll movable toward and from 25 a buffing roll in an organization wherein the work supporting roll is driven by means controlled by a treadle mechanism so arranged that the driving means for the roll becomes operative to effect rotation of the latter just before the roll presents the work piece to the bufling roll. The purpose of this arrangement is to secure buffing of the surface of a work piece while the latter is moving at a predetermined rate to insure uniformity in the product. Conveniently, the work support- 35 ing roll is at the upper end of a member which is pivoted on a horizontal axis about midway of the length of said member, the roll being driven by a chain in engagement with a sprocket wheel connected to the shaft of the roll and also with 40 a sprocket wheel in such relation to the lower end of said member as to permit swinging of the member while the driving chain is in place and in operative relation to its driving means. As shown, the chain is driven by a sprocket on a 45 shaft which carries rotatably mounted thereon a driving pulley adapted to be clutched to the shaft through the operation of a treadle mechanism which also effects movement of the work supporting roll in directions toward and from the bumng 50 roll.

Preferably and as shown, there is provided a brush roll rotatable in contact with the surface of the buffing roll to remove dust from the abrasive covering of the latter and to prevent a work 55 piece from clinging to the bufiing roll and, from being drawn into a suction means provided to carry away the dust of the buffing operations. Conveniently, said brush roll has rows of bristles spaced apart in the direction of the circumference of the roll such distances that during rota- 5 tion of the brush roll an adjacent opening into a suction conduit will be practically unobstructed at regular intervals by said roll, thereby facilitating entrance of dust-laden air into the suction means by which such air is drawn away from 10 the buffing cylinder. If desired the brush roll may be located to brush the surface of a buffed piece of work, a member being provided to back the work piece against the thrust of the brush 1 roll. 5

These and other important features of the invention and novel combinations of parts will now be described in detail in the specification and then pointed out more particularly in the appended claims.

In the drawing,

Fig. 1 is a view in side elevation, and partly in section, of a bufflng machine;

Fig. 2 is a sectional view taken along the line II ]I of Fig. 1; and Fig. 3 is a detail view of a clutch mechanism arranged to be operated by the treadle shown in Fig. 1.

In the illustrated machine, which is specially designed for performing bufling operations upon tanned hides and skins, there are provided work supporting rolls 2 and 4 mounted for rotation in the upper end of a pair of swing arms, one of which is shown at 6 in Fig. 1, the said swing arms being mounted for oscillation upon a shaft 8 carried by the front standard of the machine frame It]. Means is provided under control of a treadle l2 for moving the work supporting rolls 2 and 4 between an open or work receiving position and a work presenting position with respect 40 to a buifing roll l4 and its abrasive sheetl covering l5. Enclosing the larger part of the buffing cylinder 14 is a hood member l6 and a larger hood member H which together form part of an air suction device represented in general by reference character IS, the purpose of said device being to draw off from the neighborhood of the buffing roll 14 all of the dust-laden air which results from the bumng operations. The suction device by removing the dust helps to keep the abrasive sheet freer from dust than it otherwise would be. Located below the buffing roll or cylinder I4 is a brush roll 28 positioned adjacent to the lower opening into the air suction device to prevent the work piece from being drawn around the builing roll 14 and into the air-suction device. This brush roll also cleans the abrasive sheet II and thus gives it a longer life. I

he buillng roll I4 is preferably of that type. wherein the abrasive sheet material I 5 is wrapped around the roll and secured thereto by having its ends passed through an inclined slot in the cylindrical wall of the roll and into engagement with clamping means constructed and arranged to maintain the abrasive sheet material properly tensioned upon the cylindrical surface of the roll I4, as fully described in the said copending application.

As stated above, the brush roll 20 operates to prevent wrapping of a piece of work about the bufflng cylinder I4, and at the same time insures that the work piece will not be drawn into the suction device I0. its bristles or brush portions arranged in parallel rows spaced substantial distances from each other so that air may at certain times pass freely into a lower entrance 92 of the air-suction device I0. It is to be understood that this free passage of dust-laden air takes place at intervals during the relatively slow rotation of the brush roll 20,

the passage to the entrance 02 being exposed each time that a space between two adjacent rows of bristles reaches a position slightly beyond the position of the roll shown in Fig. 1. Each of the parallel rows of bristles presents a straight bladelike edge surface inwiping down any advancing edge of the work piece which might otherwise hug the abrasive roll and enter the suction system, it being noted in this connection that the roll 20 rotates in a direction the same as that of the abrasive or bufllng roll I4, as indicated by the arrows in Fig. 1 of the drawing, whereby the upper surface of the brush roll 20 moves in a direction the reverse of the adjacent lowersurface of the bufnng roll I4. Upon inspection of Fig. 1, it will be observed that the brush roll 20 is of a diameter such as to preclude the possibility of a work piece passing around the lower periphery of the brush roll and into the open end 02 of the air suction device I 0. As shown, the diameter of the brush roll is about double the corresponding dimension of the opening 02.

If desired, the brush roll 20 may also be positioned to brush the surface of the work which is undergoing bumng operations. For this purpose the work support, including the swing arms 0, is provided with a plate 04 to back the depending portion of the workpiece while the brush roll 20 is operating thereon, it being understood that the brush roll is adjusted to the left in Fig. 1 to the desired position to perform a brushing operation on the work. With this function in mind, the

0 brush roll 20 is mounted upon a pair of arms one of which is shown at 00 mounted rotatably upon a stud 00 carried by a plate I 00, the rear of each arm 00 being provided with a slot I02 arcuate with respect to a center at the axis of the stud 00. A second stud I04 secured to plate I00 is located in said slot I02. Upon tightening a nut I00 upon the outer end of the stud I04 the arm 00 is secured in the adjusted position shown in Fig. 1. As

clearly indicated in Figs. 1 and 2, the plate I00 is adjustably secured to the frame ll of the machine by threaded bolts I00 in a slot H0 in the plate I00, proper manipulation of the nuts on said bolts I00 being all that is necessary to permit adjustment of the plate I00 in a horizontal direction toward the front of the machine so that the brush roll 20 may operate upon portions of the work piece while the latter is backed by the plate 04.

As shown, the brush roll 20 has When this adjustment of the plate I00 is made, it is also necessary to swing the arms 00 in an upward direction through proper manipulation of the nut I 00 on the bolt I04. It will be noticed that the brush roll 20 is rotated counterclockwise to direct the work piece downwardly in a direction away from the buffing roll I4. Since the-primary function of the brush roll 20 is to prevent improper displacement of the work piece, the said roll must be adjusted in an upward direction into properly spaced relation with respect to the surface of the bumng roll at the same time that it is made to co-operate with the backing plate 04. If desired, the brush roll 20 may be left in the position shown in Fig. 1 and a separate roll provided for brushing dust from the surface of the work piece in co-operation with the plate 04 As pointed outabove, the work supporting rolls 2 and 4 are movable between an open or work receiving position and a closed or work presenting position with respect to the buffing roll I 4. This movement of the work supporting rolls is secured through proper operation of the treadle I2 during which a toggle comprising links H4 and H0 is straightened to the position shown inFig. 1 to bring the roll 4 into work presenting position relative to the bumng roll I4. As shown, the link H4 is pivoted at IIO to a member I20 which is screw threaded into a part I22 common to the two swing arms 0. Through proper adjustment of the screw threaded member I20, it is possible to vary the distance between the roll 4 and the bufling roll I4 in accordance with variations in the thickness dimensions of different lots of work.

Preferably, and as shown, the work supporting rolls 2 and 4 are positively driven to feed a work piece into the machine for the bumng operation.

ries looselya-pulley I40 arranged to be driven con- 7 tinuously by means of a belt I41 from a power shaft I50. For clutching the shaft I45 to the pu1- ley I40 there is provided a clutch mechanism, shown generally at I40 in Fig. 3, which is arranged to be operated by yoke I40 on a bell crank lever IOI connected by a long link I 02 to an arm I54 extending up from and rigidly connected to the treadle l2, the said rod I52 passing loosely through an opening in the arm I04 and having on its free end a spring I50, the arrangement being such that, upon depressing a tread portion I50 of the treadle I2, the clutch I40 is thrown in to cause driving of the work supporting rolls 2 and 4 just before the roll 4 reaches work presenting position with respect to the bufling roll I4. Conveniently there are provided work supporting plates I00 and I02 in association with the rolls 2 and 4.

As illustrated, the suction device I0 comprises not only the hood members I0 and I1 but also a conduit I10 which leads to an enclosed-blower (not shown). To insure removal of all of the dust-laden air there is provided also a supplemcntaryv conduit I12 which leads to an opening at I14 in a sheet metal pocket I10 into which the depending portions of the work piece are rereadily lifted in an upward and rearward direction. The hood member I1 is hinged at I82 so that it also may be turned upwardly and rearwardly to expose the bufling roll I4. The purpose of the hood member I6 is to provide a conduit for drawing away dust-laden air from the front portion of the buffing roll II just above the field of operation on the work piece. In spite of the strong current of air which tends to remove all dust from the periphery of the buffing tends to be carried around and it is to remove this air that the forward end of the hood member I6 is carried into close relationship with the surface of the buffing roll I. An adjustable tongue I86 is provided at the forward end of the hood member It so lower edge of the tongue I86 and the bumng roll may be adjusted, as occasion may require, to secure the best results.

As indicated in a preceding portion of this specification, the slot in the roll I4 is in a plane at an angle to the axis of rotation of the buffing roll, the purpose being to eliminate as much as possible a bumping eifect that is commonly produced each time that a slot in the cylindrical surface of a buffing roll comes opposite to the roll ll, some of the air with the rotating roll,

work backing portion of a work supporting roll during treatment of a piece of work, it being a well-known fact that there is a noticeable bumping effect in the operation of those bumng rolls which are provided with a slot parallel with the axis of rotationpf the roll. To insure that uniformity in the treatment of the work which is so desirable, the buffing roll I4 is also constantly reciprocated in an axial direction during its rotation. For this purpose there is provided a forked member I90 (Fig. l) to engage an end member of the bufling roll I4 fixed to the buffing roll shaft 24. Said forked member I90 is pivotally mounted at I92 intermediate of its ends upon a bracket extending from the frame of the machine. As its other end it is provided with a cam roll I94 arranged to ride upon the surface of a cam I96 on a shaft I98 driven by means of a pulley 200 and a belt 202 from the power shaft I50. It will be readily understood that rotation of the face cam I96 will cause reciprocation of the forked member I50 and hence of the bumng roll I4. For a more complete description of a mechanism for axially reciprocating a buffing roll during rotation of the latter, reference may be had to United States Letters Patent No. 1,377,434, granted May 10, 1921, upon application of L. O. Ramsdell.

In. operating the machine shown in the drawing to buff pieces of leather, the operator will introduce a piece of leather upon the work supporting rolls 2 and l and will then depress the treadle I2 by stepping on the tread portion I58. Depression of the treadle causes movement of the work supporting rolls 2 and l to work presenting position with respect to the bumng roll II, the treadle, when thus depressed, also initiating drive of the rolls 2 and l by the chain I34 through power means controlled by the clutch I48 (Figs. 1 and 3), and the arrangement being such that driving movement of the rolls 2 and 4 starts just prior to the engagement of the work by the buffing roll 44. It will beobserved that the piece of leather undergoing buffing operations is fed into the machine progressively during bumng of successive portions of the leather. When approximately one-half of the leather has been buffed the operator releases the treadle that the space between the which is immediately followed by movement of the work supporting rolls 2 and 4 away from the buffing roll I4 to an open position where the leather may be readily reversed and reintroduced to obtain treatment of the untreated portion thereof. Then the operations mentioned above are repeated to complete the treatment of the work piece.

Having described our invention, what we claim as new and desire to secure by Letters Patent of the United States is: V

1. In a buffing machine, a driven cylindrical roll having an abrasive surface to effect buffing of a surface of a piece of leather, a suction device having an opening adjacent to the abrasive surface of the cylindrical roll to carry away dustladen air, and a brush roll located in front of the opening into said suction device and in position to brush lightly the surface of the abrasive roll, said brush roll having its bristles in rows alternating with relatively wide spaces between the rows whereby at regular intervals during rotation of the brush roll dust-laden air may enter by way of said spaces into the suction means.

2. In a buffing machine, a driven cylindrical roll having an abrasive surface to effect buffin of a surface of a piece of leather, a suction device having an opening adjacent to the abrasive surface of said roll to carry away dust-laden air, and a brush roll rotated in a direction the same as that of the abrasive roll, whereby adjacent surfacesof the two rolls move in opposite directions, the brush roll having its bristles in rows spaced substantially from each other, said brush roll being of a diameter substantially greater than the corresponding dimension of said opening into the suction device and being located in front of said opening and adjacent to the abrasive surface of the cylindrical roll, each moving row of bristles having an edge which moves in a direction to wipe the leather from the abrasive surface of the cylindrical roll and the spaces between the rows of bristles serving at regular intervals during rotation of the brush roll to permit free access of dust-laden air to the opening into said suction means.

3. In a bufiing machine, a cylindrical roll having an abrasive surface to effect bumng of a surface of a piece of leather, a suction device having an opening adjacent to the abrasive surface of the cylindrical roll to carry away dustladen air, and a driven brush roll having its bristles in straight rows parallel to the axis of the brush roll and spaced substantially from each other, said brush roll being of a diameter substantially double the corresponding dimension of said opening into the suction device and being located in front of said opening and adjacent to the abrasive surface of the cylindrical roll, each moving row of bristles having a straight edge which serves to wipe the leather from the abrasive surface of the cylindrical roll and the spaces between the rows of bristles serving at regular intervals to permit free access of dustladen air to the opening into said suction means;

4. In a buffing machine, a buffing roll, a work supporting roll, a member movable about a horizontal axis to carry the work supporting roll in directions toward and from the buffing roll, power means to drive the work supporting roll whereby it feeds the work while at the same time supporting it against the thrust of the bumng roll, said power means comprising a clutch, and a treadle mechanism connected to the lower end of said member and to said clutch and operable to cause said member to move the work supporting roll into operative relation to the bufllng roll and to control the clutch to initiateoperation oi the driving means for said work supporting roll.

5. In a bumng machine, a bufllng roll, a work supporting roll, a member movable about a horizontal axis to carry the work supporting roll in directions toward and from the builing roll, means to drive the work supporting roll, said means comprising a clutch, and a treadle mechanism connected to operate said member thereby to tions toward and from the bufllng roll, said axis.

being about midway of the length of said memher, an idler sprocket mounted adjacent to the lower end of said member, a chain engaging said sprocket and sprocket wheel. power means to drive the chain whereby the work supporting roll feeds a work piece while at the same time supporting it against the thrust of the bumng roll, said power means comprising a clutch, and a treadle mechanism connected to said member and to said clutch to cause said member to move the work supporting roll into operative relation to the builing roll and to operate the clutch to initiate rotation of the work supporting roll Just before the latter presents the work piece to the buillng roll.

'1. In a bufling machine, a bufling roll, a work supporting roll having a sprocket wheel secured thereto, a member movable about a horizontal axis tocarry the work supporting roll in directions toward and from the bumng roll, idler sprockets mounted on the machine frame adjacent the lower end of said member, a chain engaging said sprockets and sprocket wheel, power means to drive the chain whereby the work supporting roll feeds the work while at the same time supporting it against the thrust of the bufling roll, said power means comprising a clutch, and a treadle'mechanism connected to the lower end of said member and to said clutch and operable to cause said member to move the work supporting roll into operative relation to the bufllng roll and to operate the clutch to initiate operation of the driving means for the chain-driven work supporting roll.

8. In a bufllng machine, a bufllng roll, a pair of work supporting rolls one of which is movable to a position to back a work piece during treatment thereof by the buiilng roll, said work supporting rolls having sprocket wheels secured thereto, a member movable about a horizontal axis to carry the work supporting rolls in directions toward and from -the bumng roll, idler sprockets mounted on the machine frame adjacent to and on each side of the lower end of said member, a chain engaging said sprockets and sprocket wheel, power means to drive the chain whereby the work'supporting rolls feed the work while at the same time one of them supports it against the thrust of the bufilng roll. said power means comprising a clutch, and a treadle mechanism connected to the lower end of said member and to said clutch and operable to cause said member to move said one of the work supporting rolls into direct co-operative relation to the bufllng roll and to operate the clutch to initiate operation 01' the chain driving means for said work supporting rolls.

GEORGE E. MCLAUGHLIN. WINN E. BROUGHTQN.

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