US3738349A - Cutting table for rock - Google Patents

Abstract

A device for slicing rock samples mounted on microscope slides including a sample table formed with a plurality of flat, radially disposed sample mounting surfaces extending at a slight angle with respect to the plane of the table, and mounting the table in a manner such that the sample mounting surfaces extend parallel to a circular disk-type saw blade at the leading edge point thereof and are moved gradually away from the plane of the saw blade as the cutting operation progresses.

Description

United States Pate Cooper et a1.

[11] 3,738,349 June 12, 1973 CUTTING TABLE FOR ROCK Inventors: Laurence C. Cooper, 365 S. 300 W.;

E. Blair Maxtield, 456 S. 300 W., both of Cedar City, Utah 84720 Fnem Aug. 3, 1971 Appl. No.: 168,661

U.S. Cl ..125/13 R, 51/134, 51/235,

Int. Cl 828d 1/04 Field of Search 125/13; 51/129, 134,

References Cited UNITED STATES PATENTS 6/1972 Parkhurst 125/13 R 5/1972 Beauchet....-...

12/1966 Cary Cary 125/13 R 2,414,574 1/1947 Williams 5l/235 X 2,454,777 11/1948 Cronan 1,263,057 4/1918 Griffin 51/134 Primary Examinerl-larold D. Whitehead Attorney-Lynn G. Foster [57] ABSTRACT A device for slicing rock samples mounted on microscope slides including a sample table formed with a plurality of flat, radially disposed sample mounting surfaces extending at a slight angle with respect to the plane of the table, and mounting the table in a manner such that the sample mounting surfaces extend parallel to a circular disk-type saw blade at the leading edge point thereof and are moved gradually away from the plane of the saw blade as the cutting operation progresses.

6 Claims, 6 Drawing Figures PAIENIH] JUN I 21925 SIEHIW INVENTORS. LAURENCE C. COOPER E. BLAIR MAXFIELD BY i ATTORNEY PAIEIIIEDJWZNR 3.738.349

SHEEI 2 BF 4 FIG. 2

INVENTORS.

LAURENCE C. COOPER E. BLAIR MAXFIELD ATTOR EY PATENIED J11! 1 3 INVENTORS. LAURENCE C. COOPER E. BLAIR MAXFIELD ATTORNEY PATENIED JUN I 2 SNiEI u 0? 4 INVENTORS. LAURENCE C. COOPER E. BLAIR MAXFIELD BY2 g ATTORNEY FIG. 6

BACKGROUND 1. Field of Invention This invention relates to rock cutting and is particularly directed to means for cutting thin slices of rock for use on microscopic slides.

2. Prior Art In many fields of science and commercial endeavor, such as geology, it is desirable to obtain thin slices or rock samples for use on microscopic slides to permit study of the grain structure, composition, and the like. Since most rocks are opaque, such slices must be extremely thin, on the order of a few thousandths of an inch, in order to allow sufficient light to pass through the grain structure to permit microscopic study of the rock structure. Moreover, the slices must be extremely smooth to prevent creation of light reflecting or light refracting surfaces. Unfortunately, rocks are also quite hard and, hence, do not lend themselves readily to such slicing.

Numerous methods and apparatus have been proposed, heretofore, for accomplishing such cutting. However, none of the prior art devices have been entirely satisfactory. Many of the prior art devices have been complex, bulky, and expensive. Others have been difficult to adjust or have been non-adjustable. Still others have not had sufficient precision.

BRIEF SUMMARY AND OBJECTS OF THE INVENTION These disadvantages of the prior art are overcome with the present invention and novel rock cutting means are provided which are simple, compact, and relatively inexpensive, yet are readily adjustable and provide accurate, precise slicing.

The advantages of the present invention are preferably attained by providing a sample table having a plurality of radially disposed sample mounting surfaces which extend at a slight angle with respect to the plane of the table and mounting said table for rotation about an adjustable axis which is angularly disposed in two directions with respect to the axis of an adjacent high speed saw.

Accordingly, it is an object of the present invention to provide an improved rock saw.

Another object of the present invention is to provide an improved rock saw for preparing slides for microscopic study of rocks.

An additional object of the present invention is to provide a rock saw which is simple, compact, and inexpensive.

A further object of the present invention is to provide a rock saw which is readily adjustable, yet provides accurate, precise slicing.

Another object of the present invention is to provide a rock saw having a sample table formed with a plurality of flat, radially disposed sample mounting surfaces which extend at a slight angle with respect to the plane of the table and mounting said table for rotation about an adjustable axis which is angularly disposed in two directions with respect to the axis of an adjacent high speed saw.

Another object is to produce a machine whose cutting operation is substantially automatic, eliminating the necessity of hand pressure which has been a weakness in previous machines.

These and other objects and features of the present invention will be apparent from the following detailed description taken with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a rock cutting device embodying the present invention;

FIG. 2 is a vertical section through the device of FIG. 1, taken on the line 22 thereof;

FIG. 3 is a fragmentary view, with parts broken away, showing the adjustment mechanism of the device of FIG. 1;

FIG. 4 is a fragmentary transverse section through a portion of the device of FIG. 1, taken on the line 4-4 thereof;

FIG. 5 is a vertical section through the vacuum fitting of the device of FIG. 1, taken on the line 5-5 thereof, and

FIG. 6 is a side elevation view of a portion of the apparatus illustrated in FIG. 3.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT In that form of the present invention chosen for purposes of illustration, FIGS. 1 and 2 show a rock cutting device having a generally rectangular, rigid frame, indicated generally at 2, formed by vertically extending corner posts 4, a horizontal upper plate 6, horizontal lower braces 8, and a vertical plate 10 extending between the horizontal braces 6 and 8 and serving to generally divide the interior of the frame 2 at approximately the center thereof. The frame members 4, 6, 8 and 10 are preferably formed of rigid material, such as steel, and are permanently joined by suitable means, such as welding. As seen in FIG. 2 the upper horizontal plate 6 is joined to the corner posts 4 slightly below the upper ends thereof and a tub member 12 is supported by the upper plate 6, and has vertically extending sides 14 formed with outwardly projecting flange portions 16 which rest on the upper ends of the corner posts 4.

A high-speed electric motor 18 is mounted on one side of vertical plate 10 and has a shaft 20 extending vertically therefrom. The shaft 20 projects through opening 22 in upper plate 6 and an opening 24 in tub 12 which is formed by an upwardly extending annular flange 26. The upper end of shaft 20 has an exteriorly threaded portion 28 on which is secured a blade support 30. A circular disk-type saw blade 32 which may be provided with diamond cutting surfaces or the like has a central aperture 34 which is fitted over the shaft 20 and is secured for rotation with shaft 20 by suitable means, such as flanged nut 36. In operation, the blade 32 lies in a horizontal plane and is rotated at a rate of several thousand revolutions per minute in the direction indicated by arrow 38 in FIG. 1.

The sample table 40 has a central aperture 42 which is press fit on the upper end of a shaft 44 and the table 40 is secured for rotation with shaft 44 by suitable means, such as flanged nut 46. The shaft 44 extends through a bearing 48 mounted in the upper end of a sleeve 50 which is fixedly secured to and extends upwardly from the upper arm 52 of a generally E-shaped plate 54 having a center arm 56 and a lower arm 58 projecting perpendicularly to the base 60 of plate 54. The sleeve 50 projects through an opening 62 in upper plate 6 and an opening 64 formed by upwardly extending annular flange 66 in tub 12. The openings 62 and 64 have diametral dimensions sufficiently greater than the exterior dimension of sleeve 50 to permit adjusted movement of sleeve 50 in any direction. As shown in FIG. 2, a second sleeve 68 is press-fit within sleeve 50 and has a threaded portion 70 provided at the lower end thereof which mates with an internally threaded hole 72 in middle arm 56 of the E-shaped plate 54. A spanner nut 74 surrounds sleeve 68 and bears against arm 56 to secure sleeve 68 in a desired position. The sleeve 68 has a central unthreaded portion 76 which may be externally gnurled to facilitate manual rotation of the sleeve 68. In addition, a bearing 78 is secured in the lower end of sleeve 68. The shaft 44 extends through bearing 78 and is connected to a flexible drive unit, such as universal 80, which is driven by a suitable speed reduction unit 82 by an electric motor 84. As shown, the speed reduction unit 82 and motor 84 are mounted on the lower arm 58 of E-shaped plate 54 and serve to rotate sample table 40 at a rate of about one revolution in each 48 minutes in the direction shown by arrow 86 in FIG. 1.

As seen in FIGS. 2, and 3, a rocker plate 100 extends parallel to E-shaped plate 54 and is provided adjacent its lower end with a pair of perpendicularly extending dogs 102 which embrace opposite edges of vertical plate and are pivotally secured to plate 10 by suitable means, such as screws 104. Adjacent the upper end of rocker plate 100, a first cap screw 106 extends in mating relation through an internally threaded hole 108 in plate 100 and bears against the surface of vertical plate 10 to adjust the spacing of the upper end of plate 100 with respect to plate 10. A second cap screw 110 passes through an unthreaded hole 112 in rocker plate 100 and is received in a threaded recess 114 in vertical plate 10 to secure rocker plate 100 inthe adjusted position. The E-shaped plate 54 is pivotally secured to rocker plate 100 by a cap screw 116 which passes through an unthreaded hole 118 in plate 54 and is received in a threaded recess 120 in rocker plate 100. Cap screw 122 passes through a washer 124 and an arcuate unthreaded opening 196 in the E-shaped plate 54 and is received in a threaded recess 128 in rocker plate 100 to secure the E-shaped plate 54 in the desired position.

The sample table 40 has its upper surface formed with a plurality of flat, generally-triangular areas 130 having their apeces located at the center of the sample table 40 and extending radially therefrom. At the periphery of sample table 40, the triangular areas 130 are separated by triangular raised stops 132 which are dimensioned so that the facing sides of adjacent stops are parallel, as seen at 134 in FIG. 1. Moreover, the flat surfaces of the triangular areas 130 are inclined downwardly at an angle of about one quarter of a degree with respect to the plane of the sample table 40, as indicated at 136 in FIG. 2. Three triangularly spaced studs 138 are provided on each of the flat areas 130 and co operate with the facing edges 134 of the adjacent stops 132 to position a microscope slide, as seen at 140, to which is suitably secured a rock sample 142 to be sliced.

The slides 140 are preferably secured to the flat surfaces 130 of sample table 40 by means of vacuum. As seen in FIGS. 1, 2, and 5, the under side 160 of the sample table 40 has an annular recess 162 formed therein having a plurality of ports 164 each communicating the recess 162 with a respective one of the flat surfaces 130. A vacuum cup 166 is slideably positioned within the recess 162 adjacent the leading edge point 154 of saw blade 32. The cup 166 is elongated in the direction of recess 162 and is formed with a recess 168 in the upper surface thereof extending substantially the full length of cup 166 and has a lower neck portion 170 formed with an axial bore 172 which communicates with the recess 168. The neck 170 is press fit within one end of an L-shaped bore 174 formed in a suitable support member'176, while the other end of bore 174 is connected by a hose 178 to a suitable vacuum source, not shown.

As indicated above, the cup 166 is slideably positioned within recess 162 adjacent the leading edge point 1540f saw blade 32 and, as best seen in FIG. 5, extends some distance on either side of the leading edge point 154. The cup 166 is fixedly positioned by support member 176 with the result that sample table 40 moves with respect to cup 166. Thus, as each of the flat surfaces 130 approaches the leading edge point 154, the port 164 thereof will be moved into communication with recess 168 of cup 166. When this occurs,

air from port 164 and the under side of microscope slide 140 will be withdrawn through cup 166, bore 174, and hose 178, causing air pressure above the slide 140 to press the slide 140 firmly into engagement with the flat surface 130. Due to the dimensions of cup 166, this condition maintains until the cutting operation is completed and sample table 40 is moving the slide 140 downward away from saw blade 32. As this movement continues, port 164 will move beyond the end of cup 166, whereupon air will pass under sample table 40 and through recess 162 and port 164 to neutralize the retaining force on slide 140. Finally, a nozzle 150 is connected to a suitable water supply, not shown, and is positioned to spray water on the upper and lower surfaces of saw blade 32 to provide a cooling film therefor and to wash off rock fragments resulting from the slicing operation. A drain 152 is provided to discharge the water from tub 12 and is preferably provided with a suitable strainer, not shown, to retain the rock fragments within the tub 12.

In use, it will be seen that sample table 40 is adjustable in six directions. It can be rocked forwardly or rearwardly by adjustment of cap screws 106 and which cause rocker plate 100 to pivot about screws 104 toward or away from vertical plate 10; it can be tilted to one side or the other by adjusting cap screw 122 and pivoting the E-shaped plate 54 about cap screw 116; and it can be adjusted upwardly or downwardly by loosening spanner nut 74 and rotating sleeve 68 to cause axial movement of shaft 44. Preferably, the sample table 40 is adjusted so that the flat areas are horizontal when they are presented to the leading edge of the saw blade 32 at 154 and move downwardly away from saw blade 32 as they progress toward the trailing edge of saw blade 32 at 156. Obviously, the spacing of the flat areas 130 below the saw blade 32 at the leading edge point 154 will depend upon the desired thickness of the rock slice to be cut. Normally, this spacing will be such that the top of the miscroscope slide is approximately five thousandths of an inch below the bottom of the saw blade 32. When adjusted as described, it will be seen that the sample table 40 will provide a flat horizontal support for the rock samples 142 mounted on the microscope slides 140 which is parallel to the saw blade 32 at the leading edge point 154 where the slicing operation begins. As the slicing operation progresses, the finished rock slice mounted on the slide 140 will be moved downwardly away from the saw blade 32, while the rock fragments above the saw blade 32 will be washed off of the saw blade 32 by the stream of water from nozzle 150 and will be deposited in the tub 12.

Where adjustments of extreme precision are required, the modified adjustment mechanism shown in FIG. 6 may be employed. As shown, a collar 180 is fixedly secured to the central unthreaded portion 76 of sleeve 68, as by Allen screw 182, and the collar 180 is provided with suitable indicia 184 which represent incremental positions about the sleeve 68. A suitable arm 186 is mounted on upper arm 52 of E-shaped bracket 54 and depends therefrom to a position adjacent collar 180. Arm 186 is pointed at its lower end 188 and cooperates with the indicia 184 on collar 180 to indicate the rotational position of sleeve 68 and, hence, indicates incremental vertical adjustment of table 40.

For tilting adjustments, a boss 190 is secured to one edge of rocker plate 100 and projects forwardly therefrom. The boss 190 is formed with an aperture 192 extending transversely therethrough and a threaded shank 194 is welded, or otherwise fixedly secured to one edge of lower arm 58 of the E-shaped bracket 54 and projects through aperture 192 of boss 190. An adjustment nut 196 is carried by threaded shank 194 and is interposed between boss 190 and bracket 54. Rotation of adjustment nut 196 causes nut 196 to bear against boss 190 and, through shank 194, serves to move lower arm 58 of E-shaped bracket 54 toward or away from boss 190 and causes the E-shaped bracket 54 to rotate about screw 116 to effect tilting of the table 40. A backing nut 198 is carried by shank 194 externally of boss 190 and cooperates with adjustment nut 196 to clamp against boss 190 to lock shank 194 and, hence, the E-shaped bracket 54, in a desired position.

Obviously, numerous variations and modifications may be made without departing from the present invention. Accordingly, it should be clearly understood that the form of the present invention described above and shown in the accompanying drawing is illustrative only and is not intended to limit the scope of the invention.

What is claimed is:

l. A rock slicing device comprising:

a circular disk-type saw blade, means for rotating said saw blade at a high rate of speed,

a sample table formed with a plurality of flat samplereceiving surfaces about the periphery thereof, each extending downward at a slight angle with respect to the plane of said table, and having a portion of said table positioned adjacent said saw blade in sample cutting relation,

drive means for slowly rotating said table in a direction opposite to the direction of rotation of said saw blade, and

positioning means adjustable to position said table with its axis of rotation at an angle to the axis of rotation of said saw blade thereby to position said surfaces parallel to said saw blade at the leading edge point thereof, and to cause said surfaces to be moved away from the plane of said saw blade as the cutting operation progresses.

2. The device of claim 1 wherein:

said surfaces are generally triangular and are arranged with the apeces thereof at the center of said table and said surfaces extend radially outwardly from said center.

3. The device of claim 2, further comprising:

a plurality of triangular stop members disposed about the periphery of said table between adjacent ones of said surfaces and dimensioned so that the facing edges of said stop members define parallel surfaces.

4. The device of claim 3 further comprising:

a plurality of stud members disposed about each of said surfaces and cooperating with said stop members to position microscope slides on said surfaces.

5. The device of claim 1 wherein said positioning means comprises:

a frame member,

a first plate extending generally parallel to said frame member and pivotally secured to said frame member,

first screw means extending through said first place and bearing against said frame member to pivotally adjust said first plate with respect to said frame member,

second plate means formed with an arcuate opening extending therethrough,

second screw means pivotally securing said second plate to said first plate,

third screw means extending through said arcuate slot and engaging said first plate to secure said second plate to said first plate in an adjusted pivotal position about said second screw means, and

telescoping shaft means carried by said second plate and interconnecting said drive means with said sample table.

6. The device of claim 1 wherein said slight angle is about one quarter of a degree.

Claims (6)

1. A rock slicing device comprising: a circular disk-type saw blade, means for rotating said saw blade at a high rate of speed, a sample table formed with a plurality of flat sample-receiving surfaces about the periphery thereof, each extending downward at a slight angle with respect to the plane of said table, and having a portion of said table positioned adjacent said saw blade in sample cutting relation, drive means for slowly rotating said table in a direction opposite to the direction of rotation of said saw blade, and positioning means adjustable to position said table with its axis of rotation at an angle to the axis of rotation of said saw blade thereby to position said surfaces parallel to said saw blade at the leading edge point thereof, and to cause said surfaces to be moved away from the plane of said saw blade as the cutting operation progresses.

2. The device of claim 1 wherein: said surfaces are generally triangular and are arranged with the apeces thereof at the center of said table and said surfaces extend radially outwardly from said center.

3. The device of claim 2, further comprising: a plurality of triangular stop members disposed about the periphery of said table between adjacent ones of said surfaces and dimensioned so that the facing edges of said stop members define parallel surfaces.

4. The device of claim 3 further comprising: a plurality of stud members disposed about each of said surfaces and cooperating with said stop members to position microscope slides on said surfaces.

5. The device of claim 1 wherein said positioning means comprises: a frame member, a first plate extending generally parallel to said frame member and pivotally secured to said frame member, first screw means extending through said first place and bearing against said frame member to pivotally adjust said first plate with respect to said frame member, second plate means formed with an arcuate opening extending therethrough, second screw means pivotally securing said second plate to said first plate, third screw means extending through said arcuate slot and engaging said first plate to secure said second plate to said first plate in an adjusted pivotal position about said second screw means, and telescoping shaft means carried by said second plate and interconnecting said drive means with said sample table.

6. The device of claim 1 wherein said slight angle is about one quarter of a degree.

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