US 729667 A
Description (OCR text may contain errors)
No.729,667. PATENTED JUNEZ,1903f" W. v. ROBINSONi GRINDING MACHINE.
APPLICATION FILED MAY 31, 1902. N0 MODEL. 2 SHEETS-SHEET 1 PATENTED JUNE 2. 1.903.
w. v. ROBINSON. GRINDING MACHINE. APPLICATION FILED MAY 31, 1902.
no MODEL. 2 sums-imam UNITED STATES Patented June 2, 1903.
WILLIAM V. ROBINSON, OF DETROIT, MICHIGAN.
SPECIFICATION forming part of Letters Patent No. 729,667, dated. June 2, 1903.
Application filed May 31, 1902.
tion, reference being had therein to the accompanying drawings.
The invention relates to grindin gmachiues, and is more particularly designed for use in the finishing of castingssuch, for example, as stove-plates.
It is the object of the invention to obtain a machine in which the Work of'finishing may be carried on automatically throughout the entire operation and one which will enable a single unskilled attendant to turn out in the same time the work usually requiring a number of skilled artisans.
The invention consists first in the means employed for guiding the grinder into operative relation to the work and in protecting the edges and other unfinished portions of the work from said grinder.
More specifically, the invention consists in the peculiar construction and arrangement of a marginal protecting-plate upon which the grinder bears before being fed onto the work and which prevents the edges of said work from being injured by the grinder.
' The invention furtherconsists in the peculiar construction of the holders for the work during the grinding operation with which the work is adapted to be engaged withoutclamping and, further, in the peculiar construction, arrangement, and combination of parts, as hereinafter described and claimed.
In the drawings, Figure 1 is a sectional perspective view of thegrinding-inachine. Fig. 2 is a longitudinal section throu'ghthe guideway for the grinder-frame, showing. means of adjusting said frame in relation thereto. Fig. 3 is a front elevation of the machine. Fig. 4 is across-section through one of the holders, and Figs. 5, 6, 7, and 8 illustrate modified forms of constructions of holders.
Generally described,the machine comprises an endless carrier A, adapted toffeed a series of work-holders B, which in their travel pass across the path of one or more reciprocating grinders 0, said grinders being movable toward or from the work and being pressed in contact with the face of the work with a1im= ited tension. To permit of the free movement of said grinder toward and from the work, it is preferably carried by a jointed frame having a horizontalsection D and a vertical section E, said sections being pivotally connected to each other and the latter pivoted to stationary bearings, such as the hangers F. Movement is imparted to the grinderthrough the medium ofa drive-shaft G, journaled in the hangers F, and the belt connections H and I, respectively, connecting the shaft G with a counter-shaft J at the pivotal point of the frames D and E and said counter-shaft with the arbor of the grinder C. The grinder-frame may be reciprocated by any suitable mechanism such as a pitman 'K, actuated by mechanism not shown.
The parts thus far described form no part of the present invention and may be varied as desired, the only essential being that the rotary grinder-wheel C be reciprocated across the path of the carrier and that it be free to move toward 'or from the Work during its reciprocation.
In order to limit the movement of the grinder-wheel toward the work, a guide is preferably arranged, such as L, with which a portion, such as the antifriction-roll L on the frame D, engages. This guide and roll will prevent the grinder-wheel from moving downward beyond a certain level, but do not interfere with its upward movement, so that it is free to ride over the raised'portions of the work. The grinder wheel is pressed downward with a limited pressure, which may be efiected by the gravity of the frame D, partially relieved by the counterweight M, said weight being connected to one end of the lever M, while the opposite end thereof is connected by a link or chain M with the frame D. By adjusting this counterweight any desired downward pressure maybe placed upon the grinder O. The roll 'L' is preferably adj ustably secured to the frame D, as by the adjusting-screw L so that the limit of downward movement of the grinder may be varied. The guides L are secured to any suitable stationary support, such as the bar L I The castings which are to be finished by the machine usually vary greatly in form and present both round and fiat surfaces, as well as unfinished projections which must be protected from the action of the grinder. In order that the work may be carried on expeditiously, it is desirable that these castings may be fed to the machine in any order. This precludes the possibility of guiding the grinder in relation to the face of the casting by any fixed cam, as each separate casting would need a different form, and even if the are injured by the grinder in passing on or oiffrom the casting. Moreover, with certain classes of work there would be danger of the wheel catching upon the edges or projecting portions of the casting, so as to do injury to either the casting orthe machine. 7 To overcome this difficulty, Ihave arranged protecting plates or strips. These are arranged upon the work-holders beyond the edges of the work and adjacent to any projecting portion of the work which must be protected. They are also preferably formed of material which is harder than the castings to be ground.such, for instance, as chilled castiron. Thus the grinder will have comparatively little abrasive action upon the protecting-strips in comparison with that produced on the casting to be finished. By arranging these protecting-strips around the margin of the work, as indicated at N, they will also constitute a holder for the work which secures it from lateral movement while operated upon by the grinder. \Vhere the work is of irregular form, the holder therefor is formed with a supporting-bedNof similarshapeandtheprotecting-strips N are arranged around the margin, as shown in Figs. 1 and 4. Where the work is open centrally,a protecting strip or plate,such as 0, Fig. 5, is placed therein, and where a number of castings maybe fitted together in the same holder they are provided with marginal protecting-plates, and, if necessary, intervening protecting-plates, such as P, Fig. 6.
. Again, where a projecting portion, such as a hinge-lug Q, Fig. 7, needs to be protected a plate or strip, such as R, is placed adjacent thereto, over which the grinder-Wheel will ride without injury to the lug Q.
In order that the finishing of the castings may be completed by once passing them through the machine, I preferably arrange a series of grinders C G, 850., each being provided with a jointed frame, the sections D of which are independently movable; but, if desired, the sections E may constitute a com mon frame and have a single reciprocating device. The grinders O O, &c. may be graded according to the nature of the work to be finished, so that the castings are rough-ground while passing the first grinders and are more highly finished by the later ones in the series. The employment of a series of grinders in this manner also permits of limiting the pressure of each grinder upon the work. Thus only a small amount of material is ground off by each, which permits the wheel to more perfectly conform to the shape of the casting. Moreover, where the pressure of the grinder is light it will have but little effect on the marginal protecting-strip, which greatly lengthens the life thereof.
The marginal protecting-strips N are preferably of a form which tapers downwardly toward the outer edge to the limit plane of downward movement of the grinders. Thus where the edges of the casting are some distance above this plane the grinding-wheel will mount up the incline of the marginal strip N, which will guide it onto the face of the casting. These marginal strips preferably conform to the shape of the edges of the casting; but this is not absolutely essential,as the edge of the casting might be of irregular form and that of the protecting-strip straight, as shown in Fig. 8. It is only necessary that the strip be near enough to the edge .of the casting'so that it will hold the wheel from injuring said edge.
The bed N of each holder preferably has a detachable engagement with the carrier and may be held in relation thereto by suitable guides, such as S, upon the frame or bed T of the carrier. This construction. permits the attendant to first place the castings in engagement with each holder and then successively engage them with the carrier, by which they are fed through the machine, after which they are removed and new castings substituted for the finished ones. This detachable feature is not, however, absolutely necessary, as the castings might be dropped into engagement with the holders at one end of the machine during the movement of the carrier and removed therefrom at the oppo site end.
What I claim as my invention is- 1. In a grinding-machine, the combination with a'grinder adapted to be reciprocated across the surface of the work and yieldingly pressed in contact therewith, of a marginal guard surrounding the work upon which said grinder is adapted to ride at the edge of the work to protect the latter from injury, said guard being fashioned in conformity with the longitudinal vertical contour of the edge of the work.
2. In a grinding-machine, the combination with a work-carrier adapted to feed a series of variable pieces of work, of a grinder having a reciprocating movement across the path of said carrier and yieldingly pressed toward the surface of the work thereon, and 2. marginal. guard for each piece of work on said carrier said guard surrounding the work and adapted to protect the edge thereof from in- ICC jury by said grinder, said guard being fashioned in conformity with the longitudinal vertical contour of the work.
3. In a grinding-machine, the combination of a work-carrier adapted to feed a series of separated pieces of work, of variable surface contour, a grinder having a reciprocatory movement across the path of said carrier and yieldingly pressed toward the surface of the work thereon, means for limiting the inward movement of said grinder toward said carrier, said limit being below the lowest point in the surfaces to be ground, and a marginal guard upon which said grinder is adapted to ride in entering upon each separate piece 01" the work, said guard being adapted to guide said grinder into contact with the surface of the work and to protect the edges thereof from injury.
4. In a grinding-machine, the combination with a grinder adapted to be reciprocated across the surface of the. work and yieldingly pressed in contact therewith, of a guard upon which said grinder is adapted to ride protecting a portion of the work from being ground, said guard constituting part of the holding means for the work.
5. In a grinding-machine, the combination with a grinder having a reciprocatory movement across the surface of the work and yieldingly pressed in contact therewith, of a holder recessed to receive the work, the marginal portions thereof forming guards upon which said grinder is adapted to ride on entering upon and leaving contact with said surface of the work, said marginal portion conforming to the vertical contour of the edge of the work and protecting the edges thereof from injury.
6. In a grinding-machine, the combination with a grinder adapted to be reciprocated across the surface ofthe work, of a guard upon which said grinder is adapted to ride, to protect a portion of the work from being ground, said guard constituting part of the holding means for the work.
7. In a grinding-machine, the combination with a grinder adapted to be reciprocated across the surface of the work, of a guard surrounding the work upon which said grinder is adapted to ride to protecta portion of the work from being ground, and means for yieldingly pressing said grinder into contact with the work.
8. In a grinding-machine, the combination with a grinder adapted to be reciprocated across the surface of the work, of a guard sun rounding the work upon which said grinder relieving the pressure of the grinder upon the work. 9. In a grinding-machine, the combination with a grinder adapted to be reciprocated across the surface of the work, of a guard surrounding the work upon which said grinder is adapted to ride to protect a portion of the Work from being ground, and means whereby the grinder may have a slight automatic vertical movement independent of its supporting-frame.
In testimony whereof I affix my signature in presence of two witnesses.
WVILLIAM V. ROBINSON.
HARRISON L. DAVIES, HARRY C. KENDALL.