US2527554A - Abrading contact wheel - Google Patents

Description

Patented Oct. 31, 1950 ABRADING' coarser wnenr.

Arthur E. Kimball, Chicago, Ill., asaignor to Minnesota Mining & Manufacturing Company, St. Paul; Minn., a corporation of Delaware I Application April 16, 1945, Serial No. 588,645 1 Claims. (Cl. 51-135) This invention relates to a contact wheel of the type used in abrading operatiom either as a wheel over which an abrasive coated belt is run or as a wheel upon which an abrasive coated band is fitted. In the use of wheels of this kind, whether the wheel is used with an abrasive belt or as a mounting for an abrasive band, or as a set-up wheel in which an adhesive and abrasive grain are applied directly to the face of the wheel, the work to be ground or finished is applied against the abrasive surface which is backed by the wheel.

The objects of this invention are to provide a wheel which. is sufficiently resilient to cushion the work without unduly weakening the abrasive surface of the wheel, belt or band; and to provide a wheel which, though resilient, is sumciently rigid and strong to remain concentric in use and to support the belt or band sufilciently firml to form a good abrading contact.

A further object of the invention is to provide a contactwheel of this type which, in spite of its resilience, does not have a great deal of internal friction to generate heat.

Another object of the invention in its modified forms is to provide cooling devices on a wheel of this type which will carry off heat that may be generated within the wheel or during the abrading operation within which the wheel is employed.

These and other features of the invention will be seen from the following detailed specification read in connection with the accompanying drawings forming part thereof and in which- Fig. 1 is a preferred form of this invention in the form of a contact wheel shown in use with an abrasive belt;

Fig. 2 is a section of the wheel shown in Fig. 1 on the line 22 thereof;

Fig. 3 is an elevation of a fragment of a wheel incorporating a modified form of the invention;

Fig. 4 is a middle section of the wheel shown in Fig. 3;

Fig. 5 is an elevation of a fragment of a wheel incorporating a second modification of this invention; and

Fig. 6 is a middle section of the wheel shown in Fig. 5.

Referring to the drawings (Fig. l), the wheel H is shown as one wheel upon which the abrasive coated belt I2 runs. The belt also runs over the pulley I3 and either the pulley l3 or the wheel ll may be driven to drive the belt ii.

The wh el is shown fitted upon the-arbor l4 2 and is held there by means of the clamping side plates and the nut l8. The wheel is composed of a textile or fabric material which may be stitched pads of cotton material or may be pads of felt, hair or other fibrous materials, or other materials forming ordinary bufi sections.

While the materials shown in the drawings are shown merely as cloth pads ll stitched together with the stitching it, these pads may be composed of materials impregnated with soft plastics, rubber, or other cements or coated on adjacent surfaces with similar materials, which will hold the pads together but'nevertheless leave them yielding, flexible, and resilient.

In the preferred embodiment shown in Figs. 1 and 2 the wheel is made up of a plurality of pads H which are circular in form and supported by intervening pads i9 and 2|, the former cut into small circular pads and the latter into annular pads which are in outer diameter equal to the size of the outer diameter of the pads ll.

The inner pads is must be sumciently small so that when'assembled, as indicated in Fig. 2, they leave the annular voids or chambers 20 which are of the thickness of the pads l9 and 2!.

The" size of the annular chambers 20 may be varied without affecting the principle of this .invention but it is necessary that they lie in substantial part beyond the circumference of the clamping side plates so as notto interfere with the clamping pressure of the side plates or to subject the wheel to deformation or collapse when the clamping plates are applied. The radial width of the annular pads 2i must be sufliciently great to give firm but yielding support to the abrasive coated band or belt which is borne by the wheel when the work is applied.

The various pads can be secured to each other by means of stitching or suitable soft cements which will permit them to yield and deform together, or can be held together b the clamping side plates or the wheel arbor.

In the modification shown in Figs. 3 and 4, the construction is substantially like that of the form shown in Figs. 1 and 2 with the addition of the spaced holes 30 cut into the'outer and middle pads l1 and entering upon the voids 20 so as to permit a flow of air through the chambers 20 both to increase the resiliency of the wheel and to improve the dissipation of heat generated by the wheel and by the grinding action of the band or belt being driven thereby.

While the holes or openings 30 are shown circular in form, they may necessarily be varied 3 in sise. shape. and number without aiiectin the cation, direction, and size.

lnl'igJthewheelisindicatedastravelingin a oounter-clockwise'direction with the radial passages Ill and its out at an inclination to the radius oi the wheel to give the most desirable flow of air through the channels. Ob-

viomly, these radial passages may be cut at 4111-" ierent angles with alteration only in the eiiects produced. I

Where the wheel is employed with liquid coolants or lubricants the passages shown in the forms illustrated in Figs. 3-6 inclusive may be employed to circulate coolant through the wheel although the general practice is to operate wheels of this type in the open air.

Method ofopemtion With the wheel assembled as shown in vFig. 2 the wheel can be sumciently deformed merely by pressure oi the hands to slip the belt I! over the pulley l3 and the face of the wheel ll, or conventional take-u devices can be used for that We. Iithe wheelisusedwithabandwhich merely fits over the periphery of the wheel, the wheel can be similarl 'deformedwhile the band is applied. Although the band may at rather loosely, as soon as the wheel is rotated at' the high speeds employed in grinding, the centrifugal action tends to expand the wheel to its normalsiseandtosnuglysripthehand onits inher surface.

As the wheel is rotated, whether used with a belt or band, when the work" is pressed against the abrasive coating the wheel, because of the voids or chambers 20, will yield slightly so that the belt or band bears evenly against surfaces whether iiat or irregular or curved in their contours. Because of the fabric construction the yielding of the wheel is accomplished without any substantial movement of its parts against each other and the internal friction and accompanying generation of heat within the wheel are kepttothe minimum. a

In the forms shown in Figs. 8 and 4 the deformation of the wheel, which alters the size and shape of the voids it, is accompanied by a pumping action by which the air within the chambers is constantly moved and a circulation oi air eiiected through the wheel.

. This pumping action, as well as the rotation of the wheel in the form shown in 1"iss. 5 and While I have shown this wheel in each case composed of five pads, the principle of the invention is not dependentupon either the number or size of pads used.

If the wheel is used as a set-up wheel, it would be assembled and then treatedwith the bonding agent and abrasive grits in the conventio manner.

Having thus shown and described several embodiments of the invention, it is to be understood that it is capable of many modifications.

Changes, therefore, in the construction and arrangement may be made without departingirom the spirit and scope oi the invention as disclosed in the appended claims, in which it is intended to claim all novelty inherent in the invention as broadly as permissible, in view of the prior art.

What I claim is: l. A contact abrading wheel comprising a plurality oi circular resilient pads, a plurality of smaller pads separating them, and a plurality oi annular pads having an inside diameter greater than the diameter of the smaller pads and each surrounding one-of the smaller pads to provide annular chambers in the wheel, the circular resilient pads having openings cut therethrough and entering upon the annular chambers in the wheel.

2. A contact abrading wheel for abrasive bands and belts comprising a plurality oi circular resilient pads, a plurality of smaller pads separating them, a-plurality' of annular pads having an inside diameter greater than the diameter of the smaller pads and each surrounding one of the smaller pads to provide annular chambers in the wheel, the circular resilient pads having openings cut therethrough and entering upon the annu-. lar chambers in the wheel and the annular pads having radially arranged passages extending therethrough from the chambers to the periphery of the wheel.

3. A contact abrading wheel for abrasive bands and belts comprising a plurality oi circular resilient pads, a plurality of smaller pads separating them, a plurality of annular pads having an inside diameter greater than the diameter of the smaller pads and each surrounding one oi the smaller pads to provide annular chambers in the wheel, the circular resilient pads having open- 6 eiiects a movement oi the air 'not only through the openin II but also throush the radial passages I22 and I". If the passages i2! and ill are cut as shown in Fig. 5 the movement oi the wheel in a counter-clockwise direction will result in a low pressure area in back of these passages and the. air will be thus drawn through til?a og'enings is, chambers 2| andpassages I22 ings cut therethrough and entering upon the annular chambers in the wheel and the annular pads having radially arranged passages extending therethrough irom the chambers to the periphery of the wheel and the circular resilient pads having radially arranged passages extending from 'the openings cut therethrough to the periphery oi the wheel. 7 I 4. A contact wheel for use in abrading operations comprising a plurality of coaxial circular sections of resilient material in sheet form oi substantial thickness and means for retaining saidcircular sections in cooperative relation with each other to form a body having a cylindrical surface, said circular sections being arranged to provide spaced and longitudinally aligned continuous annular chambers within the body of said wheel, certain oi said circular sections being provided with transverse apertures communicating with said continuous annular chambers. v 5. A contact wheel as set forth in claim 4 wherein certain of said circular sections are provided with substantially radially arranged passages extending irom the cylindrical surface of said wheel to the open space therein.

6. A contact wheel for use in abrading operations comprising a plurality oi coaxial circular sections of resilient material in sheet form of substantial thickness and means for retaining said circular sections in cooperative relation with each other to form a body having a cylindrical surface, said circular sections being arranged to provide one or more continuous annular chambers within the body of said wheel, certain of said circular sections being provided with transverse apertures communicating with said continuous annular chambers.

'7. A contact wheel as set forth in claim 6 wherein one or more of said circular sections are REFERENCES CITED The following references are of record in the flle of this patent:

provided with substantially radially arranged passages extending from the cylindrical surface of said wheel to an open space therein ARTHUR E. KIMIBALL UNITED STATES PATENTS Hague Aug. 8, 1939