US2238704A

US2238704A - Surface grinding machine

Info

Publication number: US2238704A
Application number: US302645A
Authority: US
Inventors: Paul V Miller
Original assignee: Taft Peirce Manufacturing Co
Current assignee: Taft Peirce Manufacturing Co
Priority date: 1939-11-03
Filing date: 1939-11-03
Publication date: 1941-04-15
Anticipated expiration: 1958-04-15

Description

April 1941- P. v.' MILLER 2,238,704

SURFACE GRINDING MACHINE 22 24 "mflllllj i 1 N 11! mm .19 V W I lllllllllllllllll INVENTOR Pal! J/z'ller JP LLLYAJ;

I m ATTORNEYS A9141 1941- P. v. MILLER 2,238,704

SURFACE GRINDING MACHINE Filed Nov. 3, 1939 4 Sheets-$heet 2 INVENTOR walk/21171 M ATTORNEYS April 15, 1941. P. v MILLER SURFACE GRINDING MACHINE Filed Nov. 3, 1939 4 Sheets-Sheet 5 mvslg-ron Paul Kflfzller M ATTORNEYS/5 Patented Apr. 15, 1941 SURFACE GRINDING MACHINE Paul V. Miller, Woonsocket, R. L, assignor to Taft-Peirce Manufacturing Company. Woonsocket, R. L, a corporation of Rhode Island Application November 3, 1939, Serial No. 302,645

4 Claims. I (01. 51-168) This invention relates to improvements in grinding machines and more particularly to improvements in machines of the type known as surface grinders employing rotary grinding elements.

An object of the present invention is to provide a surface grinder in which the grinding element is tiltable, within limits, without substantial elevation or lowering of such element relative to a work surface.

Another object of the invention is to provide a mounting for a rotary grinding element, the mounting being of such character as to be tlltable about an axis extending horizontally through the center of the grinding element.

Another object of the invention is to provide a surface grinder in which the spindle for the rotary grinding element is carried in a block supported for tilting movement about an axis remote from one end of the block.

An additional object of the invention is to provide in a surface grinder a spindle carrying block held in assembly with a yoke by means of segments which are releasable and which can be locked to locate the block any desired angular position relative to the yoke.

A further object of the invention is to provide a spindle carrying block of such construction as to receive in the side walls thereof segment strips formedon different radii whereby the'block can be tilted on such strips about a common axis remote from one end of the block.

A still further object of the invention is to provide a combined safety guard and lighting panel at one end of the table of a surface grinder, such panel having a source of illumination therein whereby alignment of material to be operated upon is facilitated.

Other features objects and advantages of the invention will be apparent by reference to the following detailed description read in the light of the accompanying drawings wherein Fig. 1 is a front perspective view of a machin embodying the invention:

Fig. 2'is a side view of the same machine;

Fig. 3 is a section taken substantially on the line 3-3 of Fig.

Fig. 4 is a section taken substantially on the line 44 of Fig. 3;

Fig. 5 is a section taken substantially on thegenerally the base of the machine constructed substantially in the manner shown in Fig. 1, such base having movably mounted on a part thereof a table II and movably mounted on the table II a saddle l2 to receive achuck I4. The chuck 14 can be of any desired type but preferably is of the magnetic type as shown in Fig. 1. Also secured to the base I0 at the rear thereof is a column I! mounted for vertical movement by any suitable mechanism. Movement of the table, the saddle and the column can be accomplished through manipulation of the handles H which serve to operate mechanisms connected to the respective parts. Inasmuch as the construction of these various mechanisms forms no part of the present invention, they are not illustrated or described in detail herein.

The column is made up in part of vertically extending wing portions and rearwardly extending wall members 2| considerably thinner than the wings 20. Near the top of the column, a yoke is provided, made up of parallel side walls 22 and a cap 24 secured across the top edges of the side walls. The walls of this yoke extend forward of the wings 20 as indicated at 25.

A spindle block indicated generally at 30 is mounted between the side walls 22 in a manner to be described later. This block, as shown clearly in Fig. 6, has the top part thereof hollowed out as at 3| and is provided with a through opening 32 in the lower part thereof. Opening 22 is designed to receive a quill 34 of a cartridge type spindle and motor assembly, which quill 34 has a spindle 35 mounted therein for rotation in suitable bearings all sealed within the quill. Also fastened to the rear end of the quill is a motor 36, the shaft of which is directly coupled to the spindle 35 or, if desired, the spindle 35 may be integral with the motor shaft, as is well known in this type of construction. The quill 34 is held in the opening 32 by means of set screws 31 passing through the bottom wall of the opening 32 into contact with the quill. The end of spindle 35 is provided with a suitable head 38 to which can be secured in any desired fashion, as by a nut, a headed screw, or otherwise, a rotating cutting element such as a cutting wheel 39.

The block 30 has a pair of dovetail shaped grooves 40 cut in the side walls thereof and extending from the top edge to the bottom edge of these side walls. As shown in Fig. 6 the grooves 40 are not straight but are of substantially arcuate shape being drawn each on a radius the center of which is a horizontal line passing through the center of the grinding wheel 39. or in other words a horizontal line passing through the point 4|. Also the'side walls of the block 30 are provided with a second pair of dovetailshaped grooves 42 near the rear end of the block'which grooves are also of substantially arcuate shape from the top edge of the wall to the bottom edge thereof with the curvature being formed on a radius also utilizing the same point 4| as a center.

Secured to the inner walls of the yoke are two pairs of

strip members

45 and 46 respectively. The members .45 are of trapezoidal shape in cross-section and are curved along a radius corresponding to the curvature of the grooves 40. llhe strips 45 are of such dimensions as to fit in the respective grooves 40 with a slight clearance. Each of the strips 45 is held in assembly with the side walls of the yoke by three screw members 41 passing through the extension part 25 of the yoke and threadedinto the strip 45. The strips 46 are of similar shape in crosssection and are curved along the same radius as the grooves 42. These strips are held in assembly with the yoke by sets of screws 48. One screw of each set passes through the top of each side wall 22 and the other two of which pass through the parts 2| of the column. These strips 46 fit in the grooves 42 with the same clearance as the strips 45 in grooves 40 so that when the screws 41 and' 48 are tightened, the

strips

45 and 46 are pulled firmly against the inner walls of the yoke and the bevelled surfaces of the strips are also brought into intimate contact with the bevelled surfaces of the grooves so that the block is thereby firmly locked against any movement. When the strips are so tightened in the dovetail slots, they have a wedge-like action which assures that the block cannot be moved while so locked. 1

As shown in Fig. 3, the block is capable of a tilting movement from a horizontal position shown in full lines to the dotted line position, which movement is through an angle of approximately 30. This movement being about the center 4| causes a tilting of the grinding wheel 39 but such tilting is accomplished without a material change in the elevation of the cutting edge or periphery of the grinding wheel relative to a work surface supported on the chuck l4. Furthermore, if desired, by changing the relative positions of the parts of the yoke, the angle of movement of the grinding element can be varied to other extents than that shown in the drawings. For example, upward movement of the block about the center 4| could be accomplished by raising the cap of the yoke and by extending the yoke walls upwardly, within limits. Thus, it will be seen that the mounting of the block and of the grinding element for rotation about a horizontal line extending through the center of the grinding block has the advantage of permitting angular variations in the position of the grinding element without requiring any material adjustment vertically of the column supporting the spindle block. In addition, the arrangement whereby the desired tilting is accomplished has the further advantage that the block is very efficiently locked in any adjustment position by the wedge-like action of the arcuate shaped strips when the

screws

41 and 48 are tightened.

As an auxiliary feature, the table II has a stand 60 at, one end thereof, which stand is hollowed out for the reception of an electric light bulb or the like. The open part of the stand is covered by a ground glass member 8| so that the rays of light from the bulb are diffused. This member serves admirably during setting up of work, in that an operator can efllciently line-up the work on a chuck or other support. Also a guard 65 hasa throat part fitting around the quill 34 and locked thereto by set screws 88, part of the guard 65 being shaped in the fashion of a hood as at 51.

From the foregoing it will be seen that the present invention provides a novel mounting for a spindle block in a surface grinding machine, which mounting has the advantages of per mitting angular adjustment of the grinding element without material variation in the elevation thereof and which mounting also has the advantage that the block can be more emciently locked in any adjusted position than is customary with arrangements utilizing a spindle or other single mounting element. It is to be understood that the invention is capable of modification over the illustrated arrangement; in view of which any limitations imposed'thereupon are to be only those set forth in the following claims.

What is claimed is:

1. In a grinding machine. a support for work to be processed, an elevator column having a yoke formation at the top thereof, a spindle carrying block, spaced pairs of arcuate shaped guide members, means for securing said guide members in said yoke for limited movement relative thereto, said guide members engaging said block on the opposite sides thereof for tilting movement of the block relative to the yoke, and a spindle carried by said block and extending beyond the same over said support, the guide members of each pair having a common center whereby the block is tiltable about an axis defined by a horizontal line extending through said spindle near the end thereof over said support, said means for securing the guide members in the yoke being adjustable to lock the guide members in the yoke and to so grip said block as to lock the block in any adjusted position against movement relative to the yoke.

2. In a grinding machine, a support for work to be processed, an elevator column having a yoke formation at the top thereof, a spindle block fitting closely within said yoke, and pairs of oppositely disposed guide members engaging the side walls of said block, releasable means holding said guide members captive in said yoke whereby said block can be tilted relative to said yoke, said pairs of guide members being curved on different radii having a common center which is forward of the end of said block and over said support, said releasable means being adjustable to lock both the guide members and the block against movement relative to the yoke.

3. In a grindingv machine, a support for work to be processed, an elevator column having a yoke formation at the top thereof, a spindle block fitting closely within said yoke, and pairs of oppositely disposed strips of trapezoidal shape in cross-section, adjustable securing means for holding said strips captive to the inner side walls of said yoke with a limited range of movement relative to the yoke, said block having pairs of dovetail-shaped grooves to receive said strips, said respective pairs of strips and grooves being curved on different radii having a common center which is forward of the end of said block and over said support, said securing means being adjustable to release the strips whereby the block can be tilted and to lock the strips and block against movement relative to the yoke.

4. In a grinding" machine, a support for work to be processed, an elevator column having a yoke formation at the top thereof, a spindle block fitting closely within said yoke, said block having pairs of oppositely disposed .grooves in the side walls thereof, pairs of oppositely disposed wedge members fitting in said grooves, and securing means for holding said wedge members captive to the side walls 01' said yoke. said pairs of grooves and wedge members being curved on 10 PAUL V. MILLER.