US3606178A

US3606178A - Grinding mill

Info

Publication number: US3606178A
Application number: US14559A
Authority: US
Inventors: Edward M Klopp
Original assignee: Chemical Rubber Co
Current assignee: Chemical Rubber Co
Priority date: 1970-02-26
Filing date: 1970-02-26
Publication date: 1971-09-20
Anticipated expiration: 1988-09-20

Abstract

D R A W I N G
A GRINDING MILL APPARATUS PARTICULARLY SUITED FOR GRINDING SMALL LABORATORY SAMPLES AND THE LIKE. THE DISCLOSED EMBODIMENT INCLUDES A BASE SUPPORT AND MOTOR HOUSING WITH A GRINDING CHAMBER FORMING ASSEMBLY REMOVABLY MOUNTED THEREON. THE GRINDING CHAMBER ASSEMBLY IN COMPRISED OF TWO SEPARABLE SECTIONS EACH DEFINING APPROXIMATELY HALF OF THE CHAMBER. EACH SECTION HAS AN INTERNAL SPACE FOR PERMITTING A HEAT EXCHANGE FLUID TO BE CIRCULATED THERETHROUGH. ADDITIONALLY, A GRINDING BLAME ASSEMBLY IS REMOVABLY MOUNTED IN ONE OF THE SECTIONS.

Description

E. M. KLoPP GRINDING MILL Sept. 20, 1971 5 Sheets-Sheet 1 Filed Feb. 26, 1970 INVENTOR. EDWARD M. KLOPP ATTORNEYS Sept. 20, 1971 Filed Feb. 26. 1970 E. M. KLOPP GRINDING MILL 5 Sheets-Sheet 2 'INVENTOR. EDWARD M. KLOPP ATTORNEYS.

Sept. 20, 1971 KLQPP 3,606,178

GRINDING MILL Filed Feb. 26, 1970 3 Sheets-Sheet 5 INVENTOR. EDWARD M. KLOPP BY WWW ATTORNEYS.

United States Patent 3,606,178 GRINDING MILL Edward M. Klopp, Medina, Ohio, assignor to The Chemical Rubber Company, Cleveland, Ohio Filed Feb. 26, 1970, Ser. No. 14,559 Int. Cl. B02c 18/12, 23/00 US. Cl. 241-65 6 Claims ABSTRACT OF THE DISCLOSURE A grinding mill apparatus particularly suited for grinding small laboratory samples and the like. The disclosed embodiment includes a base support and motor housing with a grinding chamber forming assembly removably mounted thereon. The grinding chamber assembly is comprised of two separable sections each defining approximately half of the chamber. 'Each section has an internal space for permitting a heat exchange fluid to be circulated therethrough. Additionally, a grinding blade assembly is removably mounted in one of the sections.

The present invention is directed toward the grinding mill art and, more particularly, to an improved rotary blade type mill.

The invention is particularly suited for small mills for use in laboratories for grinding small quantities for samples and the like, and will be described with particular reference thereto; however, it will be appreciated that the invention is capable of broader application and could be used for mills of substantially any size and use.

Grinding mills suitable for laboratory use must be capable of rapidly and efficiently griding small samples of a wide range of materials having substantially different properties. Also, it is mandatory that at least the grinding chamber portion of the mills be arranged for quick disassembly for cleaning, sterilization, etc. In addition to these requirements, it is highly desirable that there be provision for selectively heating or cooling the chamber during a grinding operation.

The three above noted factors are somewhat mutually incompatible from a design standpoint. The present invention however, provides a grinding mill which meets the requirements simply and effectively.

In accordance with the invention there is provided an improved grinding mill including first and second grinding chamber forming sections each comprised of an outer housing member having a continuous side wall, a closed lower end and an open upper end. Generally cup shaped liner members are positioned within each housing member and in combination therewith define separate sealed annular chambers. Connecting means are provided for releasably connecting the two grinding chamber forming assemblies with their open ends in face-to-face engagement whereby their liners cooperate to form a closed grinding chamber. A readily releasable rotary grinding knife and bearing assembly extends through the closed end wall of one of the housings and into grinding chamber. Additionally, there is a base assembly having a motor with a vertically extending output shaft and means carried by the base assembly for positioning the grinding chamber assembly thereon with means for pro viding a releasable drive connection between the grinding knife and the motor shaft.

Accordingly, a primary object of the invention is the provision of a grinding mill which can be readily disassembled and which is capable of grinding a variety of diiferent materials.

Another object of the invention is the provision of a rotary grinding mill of the type described wherein a heat exchange fluid can be circulated about the grinding chamber.

A further object is the provision of a grinding mill particularly suited for use in laboratories and in which the grinding chamber is comprised of two substantially identical manually releasable sections that can be completely disassembled for cleaning etc.

Yet another object is the provision of a mill of the type described which is extremely rugged and relatively simple in construction.

These and other objects and advantages will become apparent from the following description when read in conjunction with the accompanying drawings wherein:

FIG. 1 is a pictorial elevation of a grinding mill formed in accordance with the preferred embodiment of the invention;

FIG. 2 is a vertical cross-sectional view taken through the mill of FIG. 1;

FIG. 3 is an enlarged cross-sectional view through the cutter assembly;

FIG. 4 is a cross-sectional view through the grinding chamber assembly showing in detail the connecting and sealing arrangement between the grinding chamber forming members; and,

FIG. 5 is a view taken on line 5-5 of FIG. 2.

Referring more particularly to FIGS. 1 and 2, the overall mill is shown as comprised of a motor and base assembly 10 and a grinding chamber forming assembly 12. Preferably the grinding chamber forming assembly is releasably mounted on the assembly 10.

The base and motor assembly 10 could have a variety of designs and configurations but, in the preferred embodiment, includes a housing 14 formed, for example, from cast aluminum. The housing 14 is open at its lower end 16 and is provided with a relatively heavy, inwardly extending motor mounting flange 18 at its upper end. The inner corners of the housing 14 are provided with heavier portions which serve to strengthen the housing and provide means for attaching the base plate.

As shown, the open lower end 16 of the housing 14 is closed by a base plate member 22 which is formed, for example, from sheet aluminum. To assure circulation of cooling air through the motor chamber 26, the base plate member 22 is provided with a series of openings 24. Similarly, the housing 14 is provided with openings 27. A circulation of air is due to the presence of a fan, built into the motor, which pulls air through the opening 27, through and around the motor, and discharges it through the holes in the base plate.

Resilient rubber pads or feet 28 are positioned at each lower corner of the housing and releasably connected thereto by machine screws 30 which are received in threaded openings formed in the portions 20. As can be seen from FIG. 2, the base plate is fastened to the housing by the same machine screws that hold the rubber feet.

Positioned within the motor chamber 26 is a conventional, high speed electric motor 32. The motor is supported from the flange 18 by four machine screws 34 which extend downwardly through openings in flange 18 and into threaded alignment bosses on the casing of the motor '32. The motor could be of many types but is preferably capable of approximately 20,000 rpm. As shown, the motor is mounted so that its output shaft 36 extends vertically upwardly through opening 38 and into releasable engagement with the cutter assembly which will subsequently be described.

Any of a variety of types of controls could be provided for the mill. In the embodiment under consideration, the controls include an adjustable electrically driven timer 39 which mounted on the inclined face 40 of the housing 14. The timer 39 is provided with a knob 42 used to 3 adjust the timing mechanism for any predetermined period of time. Also, the timer is preferably of the type which permits it to be set for continous untimed operation of the motor. In addition to the timer, the device is provided with a pilot light 44 and a breaker for overload protection.

The apparatus thus far described is relatively conventional and could vary substantially from that shown. Of special importance to the invention however, is the arrangement of the grinding chamber assembly 12. As will hereafter become apparent, the assembly 12 could have many different constructions but, in the preferred embodiment, includes a first chamber forming assembly 44 and a cooperating second chamber forming assembly 46 which together define a closed and sealed grinding chamber 48.

The assembly 44 includes an outer housing member 50 which has a continuous outer side wall 52 which is desirably shaped so as to form a continuation of the side wall of the base housing 14. The housing 50 is preferably formed from cast aluminum and is releasably mounted and positioned on the upper edge of the base 14 by pin members 54 which extend vertically upward from the housing 14. As shown, the pin members 54 are received in openings 56 formed in the lower edge of the wall 52. This properly positions the housing 50 relative to the housing 14 while permitting it to be readily removed for cleaning, emptying, etc.

An internal inwardly extending central flange or Wall 58 is integrally formed with the wall 52. Flange 58 carries the removable cutting assembly 60 in a manner subsequently to be described. Adjacent the upper end of the housing 50 there is a second inwardly extending flange portion 62 which extends about the entire periphery of the wall 52. The flange portion 62 terminates in a cylindrical opening 64.

The actual grinding chamber is defined by a generally cup shaped liner member 68 which is positioned within the opening 64. Preferably, the member 68 is formed from stainless steel or the like so that it has good corrosion resistance and can be used for grinding a variety of materials. As best shown in FIG. 4 the upper edge of the cup shaped liner member 68 is provided with a radially outwardly extending flange 70. The flange 70 rests on the upper surface of the housing flange 62. Preferably, sealing means are arranged to provide a fluid tight seal between the flange 70 and the housing flange angle 62. In the embodiment under consideration, the sealing means includes an O-ring 72 which is releasably positioned in a groove 74 that extends circumferentially about the opening 64.

Referring again to FIG. 2, it will be noted that with the member 68 in position, the wall 52 cooperates therewith to form a generally annular shaped closed chamber 76 about the member 68. This permits a heating or cooling fluid to be circulated about the member 68 so that grinding can be accomplished at any desired temperature. In the embodiment shown, heat exchange fluid inlets and outlets extend through the wall 52. The inlet and outlets are formed by a pair of connectors 78 which are threadably received in the wall 52. The connectors 78 are the conventional type used with flexible tubing. Note that a short section of tubing 80 is shown received on the outer end of the connector 78.

The upper portion of the grinding chamber is formed by assembly 46 which is releasably connected to assembly 44. The grinding chamber forming assembly 46 is broadly similar to assembly 44. As best shown in FIGS. 1 and 4, the assembly 46 comprises a first outer housing member 82 which is preferably an aluminum casting of generally rectangular cup shaped configuration. As can be seen, the housing member 82 has a downwardly extending wall 84 which is shaped so as to form a continuation of the wall 52 of housing member 50. Positioned within the open lower end of the housing member 82 is a generally cup shaped grinding chamber forming member 88. Member 88 is preferably drawn fIQm Stainless steel.

4 As shown in FIG. 4, the cup shaped liner member 88 has a radially outwardly extending flange 90 which serves to position it within the housing member 84. Additionally, the upper wall 92 of housing member 84' is provided with a central downwardly extending boss portion 94 which engages the center of the end wall member 88.

The member 88 is removably received in the housing 84 by an annular ring member 9'6 which is press fitted within the housing 82. As shown, member 96 is received in a recess or shouldered portion 98 formed about the inner periphery of wall 84. The liner .88 is, in turn, press fit within member 96. Positioned between the lip 90 and the member 96 is a resilient gasket 100 which provides a fluid tight chamber 102 about the liner 88. The chamber can be seen in FIG. 2 and, like chamber 76, is provided with means for supplying heating or cooling fluid to maintain a desired temperature in upper portion of the grinding chamber 48. The means used for supplying fluid to the chamber 102 comprise a pair of tube fittings 104 which are received in threaded openings formed through the walls of housing 82.

The grinding

chamber forming assemblies

44 and 46 are arranged so that they can be readily released to permit access to the interior of the grinding chamber 48. These releasable means can take many forms but, in the subject embodiment, comprise cooperating engageable lip portions carried on each of the assemblies. As best shown in FIG. 5, on the assembly 44 there is connected an annular lip forming member which is arranged to extend inwardly a short distance beyond the innermost edge of the top surface of wall 52. This member is cut out at diagonally opposite positions and the upper annular ring 96 is adapted to releasably engage under the member 110 and has a pair of diagonally opposite outwardly extending lip portions 112. The lip portions are positioned so that they can pass through the openings in member 110 and, since the lips include an inclined ram portion when rotated a short angular distance clockwise, engage under lip 110 to lock

assemblies

44 and 46 tightly together.

As can be appreciated, in the apparatus thus far described, the arrangement of the grinding

chamber assemblies

44 and 46 permits them to be removed as a unit from the motor assembly 10 and, additionally, permits each of the

individual assemblies

44, 46 to be disassembled for cleaning, autoclaving, etc.

In line with the ability of the

assemblies

44 and 46 to be disassembled, the cutter assembly 60 is likewise arranged so that it can be easily moved from the assembly 44. Referring in particular to FIG. 3, it will be noted that a locking bushing member is joined, such as by silver soldering, to the lower end surface of the cup shaped member 68. The bushing member 120 is adapted to be closely received in the central opening in the circumferential flange 58. An O-ring seal 122 is received in an annular groove 124 formed about the top surface of flange 58'. This provides a tight seal for the annular chamber 76. The locking bushing 12!) is removably connected to the flange 58 by a nut 126.

Removably seated within the locking bushing. 12!) is a bearing sleeve member 128 which has an outwardly extending flange 130 at its upper end. Flange 130 rests against the upper surface of the locking bushing 120. The bearing sleeve 128 is resiliently held in position by a nut 130 which bears against a resilient cup washer 132 which is positioned as shown, between the lower surface of flange 58 and the upper surface of nut 130. A sleeve hearing 134 is carried within the bearing sleeve 128 and includes a flange portion 136 which cooperates with a recess formed within the bearing sleeve.

The cutter drive shaft 138 extends vertically through the bearing 136 and has a threaded upper end portion 140 which receives the cutter blade 142. A thrust washer 144 is positioned between the lower surface of blade 142 and the upper surface of the bearing sleeve 128. An acorn nut 146 locks the blade in position. Although not shown, the opening through the blade is threaded so that it can be threaded onto the portion 140 of the drive shaft. The drive shaft is enlarged at its lower end 148 to provide a shoulder 150 which has a suitable Washer or washers 152 positioned thereon to engage the lower end of the bearing 134.

The drive shaft 138 is, of course, releasably connected to the vertically extending shaft 36' of motor 3-2. Many types of releasable connections could be used; however, in the subject embodiment the lower end 148 of the drive shaft 138 is provided with an octagonal recess (made by superimposing two squares 45 out of phase). The motor shaft 36 is, as best seen in FIG. 2, provided with a flexible coupling the upper end of which includes a square steel drive pin which slidably engages with the recessed portion of 148.

As can be appreciated from the aforegoing description, the invention permits the grinding chamber portion of the assembly to be readily removed from the base assembly 10. The construction of the cutter assembly and the individual

chamber forming assemblies

44 and 46 is such as that they can be readily disassembled for cleaning etc. Additionally, the arrangement is such that filling and emptying of the chamber is easily accomplished and heating and/or cooling can also be carried out with a minimum of efiort.

The invention has been described in great detail sufficient to enable one of ordinary skill in the grinding art to make and use the same. Obviously, modifications and alterations of the preferred embodiment will occur to others upon a reading and understanding of the specification and it is my intention to include all such modifications and alterations as part of my invention insofar as they come within the scope of the appended claims.

Having thus described my invention, I claim:

1. An improved grinding mill comprising:

a first grinding chamber forming assembly including a first outer housing member having a continuous side wall, a closed lower end and an open upper end; a first generally cup shaped liner member positioned within said first housing member and defining a first sealed annular chamber in combination therewith;

a second grinding chamber forming assembly comprising a second outer housing member having a continuous side wall, a closed upper end and an open 6 lower end; a second generally cup shaped liner member positioned within said second outer housing member and defining a second sealed annular chamber in combination therewith;

a rotary grinding knife and bearing assembly extending through the closed end wall of said first housing and into said first liner, means for releasably retaining said grinding knife and bearing assembly therein; and,

connecting means for releasably connecting said first and second grinding chamber forming assemblies with their open ends in face-to-face engagement whereby said liners cooperate to form a closed grinding chamber.

2. The invention as defined in claim 1 including means for supplying heat exchange fluid to said first and second annular chambers.

3. The invention as defined in claim 1 including a base assembly including a motor having a vertically extending shaft.

4. The invention as defined in claim 1 wherein said connecting means comprise rotatably engagea-ble portions carried on said first and second housing members.

5. The invention as defined in claim =1 including a base assembly having a motor with a vertically extending out put shaft, means carried by said base assembly for positioning said first grinding chamber assembly thereon; and, releasable means for drivingly connecting said output shaft to said rotary grinding knife.

6. The invention as defined in claim 1 wherein said first and second liner members are generally cylindrical and of the same diameter, and wherein said liner members each have lips which extend radially and engage when said first and second grinding chamber assemblies are connected.

References Cited UNITED STATES PATENTS 3,243,128 3/1966 Tight 241- THERON E. CONDON, Primary Examiner R. L. SPRUILL, Assistant Examiner US. Cl. X.R. 24l185