CRUSHER FOR TENACIOUS MATERIAL SUCH AS ASPHALT
United States Patent 3758035
A crusher for crushing tenacious material, particularly asphalt. A horizontally arranged cylindrical casing has a rotary shaft concentrically mounted therein and at least two radial crushing rods are fixed on the rotary shaft at axially spaced locations. The casing includes end walls, one of which has an inlet opening at its upper part and a cylindrical wall which has perforations at its lower part. The crushing rod located adjacent to the inlet opening has a square cross-sectional shape with its opposite side surfaces being parallel to the end wall of the casing, and the remaining crushing rod has a square cross-sectional shape with its side surfaces being at an angle to the end wall of the casing.
US Patent References:
Method of making cream style corn
Fitzpatrick - January 1951 - 2540028

Tiltable axis attrition mill with hammer and knife rotor
Records - September 1957 - 2807424


Inventors:
Ushiku, Yoshio (Tochigi-shi, JA)
Saitoh, Hirokazu (Ohmiya-shi, JA)
Application Number:
05/148813
Publication Date:
09/11/1973
Filing Date:
06/01/1971
View Patent Images:
Assignee:
Mitsuboshi-Sangyo Co., Ltd. (Tokyo, JA)
Primary Class:
Other Classes:
241/154, 241/188.100
International Classes:
B02C13/06; B02C13/28; B29B13/10; B02C13/00; B02C13/28; B02C13/10
Field of Search:
241/73,79.2,86,186R,188R,189R,191,195,154,185R,188A,189A
Primary Examiner:
Spruill, Robert L.
Claims:
We claim

1. A device for crushing tenacious material comprising a cylindrical casing having a pair of vertical end walls and a horizontal cylindrical wall joining said end walls, one of said end walls having an inlet opening at the upper part thereof for supplying the material to be crushed into said casing and said cylindrical wall having perforations in the lower part thereof for discharging the crushed material from within the casing, a rotary shaft rotatably mounted in said casing at the center thereof, means for driving said rotary shaft, a plurality of radially extending crushing rods attached on said rotary shaft at axially spaced locations along said shaft, one of said crushing rods being located adjacent said inlet opening and having a square cross section with a flat side surface being directed toward the rotating direction thereof, and the remaining of said plurality of crushing rod having a square cross section with a corner being directed toward the rotating direction thereof.

2. A device according to claim 1 wherein each of said crushing rods has a pointed end.

Description:
SUMMARY OF THE INVENTION

The present invention relates to a crusher for crushing tenacious material, particularly asphalt.

Crushing or pulverizing of tenacious material at normal temperatures is very difficult owing to its stickiness. Various types of crushers have been proposed for this purpose, but most of them depend on cutting or shearing of the material by blades having a special configuration, so that continuous operation of the crusher is often difficult.

Accordingly, it is an object of the present invention to provide a crusher which can be continuously operated for a long time without any trouble, using a simple crushing means which serves to crush the material by the combined effect of striking and crushing.

In accordance with the present invention, there is provided a crusher which comprises a horizontally arranged cylindrical casing including end walls, one of which has an inlet opening at its upper part and a cylindrical wall which has perforations at its lower part, a rotary shaft concentrically mounted in said casing, means for driving said rotary shaft, and at least two radial crushing rods fixed on said rotary shaft at axially spaced locations therealong, the crushing rod located adjacent to the inlet opening having a flat surface facing toward said inlet opening and the remaining crushing rod having a sharp edge facing toward the direction of rotation thereof.

The invention will be more fully understood from the following description with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation view, partly in section, of the crusher according to the present invention; and

FIG. 2 is a sectional view of the crusher taken along line II--II of FIG. 1 .

PREFERRED EMBODIMENT

The drawings illustrate a preferred embodiment of the present invention which includes a horizontally arranged cylindrical casing 20 including end walls 21 and 22, and a cylindrical wall 23. The end wall 21 has an inlet opening 21a at its upper part to supply the material to be crushed to the casing and the cylindrical wall 23 has perforations 13 at its lower part to discharge the crushed material from within the casing. A rotary shaft 12 is concentrically arranged in said casing 20 and rotatably supported by bearings 10 and 10'. A pulley 11 is fixedly mounted on one end of said rotary shaft, and said pulley can be driven by belts and a motor (not shown). A supply hopper 1 is mounted on the casing and is connected to the inlet opening 21a, and a discharge chute 14 is connected to the bottom of the casing 20. A drum 6 is concentrically mounted on said rotary shaft, and a plurality of radial crushing rods 7, 8, 9 and 9' are fixed on said rotary shaft at axially spaced locations therealong and project through said drum 6 into a treating zone 5 formed in said casing 20.

Referring to FIG. 1, the tenacious material to be crushed which is supplied into the hopper 1 passes through a bent supply path 4, which has a blade 3 therealong for preventing the material from flying back along said path from the treating zone 5. At the center of the treating zone, the material is first struck and crushed by the crushing rod 7, which is positioned at one end of the rotating drum 6, and then struck by the next crushing rod 8, which is arranged at the center of the rotating drum 6 diametrically opposite the crushing rod 7. Further, the material is vigorously struck and rotated between the inside walls of the treating zone and the crushing rods 9 and 9', which are on the opposite end of the rotating drum 6 and at right angles to the crushing rods 7 and 8. Thus, the material is crushed in a few seconds into granules.

The crushing rods 7, 8, 9 and 9' are fixed on the rotary shaft 12, which is supported by the bearings 10 and 10', and rotated through the pulley 11, and they project into the treating zone 5 through the drum 6. The crushed material is discharged through the perforations 13 at the bottom of the treating zone 5 to the outside through the discharge chute 14. It is desirable to keep the space between the end surfaces of the drum 6 and the inside surfaces of the treating zone 5 to a minimum. The opening 21a from the supply path 4 to the treating zone 5 is positioned adjacent the crushing rod 7 so that the material strikes against the flat surface of the curshing rod 7 at its lower part. Thus, the crushing rod 7 is so arranged that the flat surface thereof faces toward the inside surface of the treating zone 5. The crushing rods 8, 9 and 9' are so arranged that their corners face toward the inside surface of the treating zone 5.

As shown in FIG. 2, the crushing rods 7, 8, 9 and 9' are at right angles to each other. However, the angles may be any angle other than a right angle, if desired. It has been found that it is possible to provide three to eight crushing rods, but it is most preferably to provide four crushing rods for practical use.

As explained above, the crushing rod 7 is positioned immediately adjacent the opening 21a in the supply path 4, and it is necessary to so position said crushing rod 7 that its flat surface faces the material, and to so position the crushing rods 8, 9 and 9' that their corners face toward the material. The crushing rods are most preferably made so as to have a square cross-section and a pointed end. The crushing rods have a length such that there is a very small gap between the end thereof and the inside surface of the treating zone 5, in order to prevent the material from sticking to the crushing rods. The crushing rods may have other cross-sectional shapes, such as polygonal, according to the material to be treated, but the ends of the rods must be pointed.

The blade 3 in the supply path 4 serves to prevent the material from flying back from the treating zone 5 through the hopper 1 to the outside owing to the high speed of rotation of the crushing rods, and also serves to aid the crushing action, and therefore the blade is rather important for obtaining the crushing action of this crusher.

This crusher is normally operated at the speed of 750-900 rpm, but the rotating speed may be varied, depending on the tenacity of the material to be crushed. For example, thermoplastic material may be treated at a speed of 900 rpm, and thermosetting material or inorganic material may be treated at a speed of 1,200 rpm. The perforations provided at the bottom of the treating zone may have any suitable size, and a suitable diameter is selected, depending on the material to be treated. When treating a material having high tenacity, small perforations may cause clogging. In practical use, perforations having a diameter of 10 mm produce good results. It has been found that pulverizable material can be satisfactorily treated by relatively long crushing rods in a relatively small drum, while hard material having little tenacity can be satisfactorily treated by relatively short crushing rods in a relatively large drum.

In this device the material being treated is naturally air-cooled, but a positive cooling device may be provided, if desired, to cool material having a high tenacity.

Now the invention will be further explained with reference to some examples showing practical uses of the crusher according to the present invention.

EXAMPLE 1

Pulverizing blown asphalt having a high viscosity with a penetration degree of 20-30 was carried out. The supplied asphalt had been previously divided into particles of about 15cm 3 . A rotating speed of the drum of 900 rpm produced the best results, granules having 40-50 meshes being obtained in 2-3 seconds. This result was obtained with perforations in the casing of 10 mm diameter. With the perforations of 5 mm diameter, the continuous operation of the crusher produced clogging, which is not desirable, but intermittent operation produced fine granules of 100-120 mesh size.

The granular asphalt thus obtained is a new form of asphalt, which can be advantageously used as asphalt-roofing material, and which does not require conventional melting equipment, heating equipment, conveying tubing, or the like. It can also be used as waterproofing material for building or construction, paving material for roads or floor sealing material or the like. Thus, the granular asphalt can be employed in a simple way in a wide field, including ones where conventional asphalt has been used heretofore.

EXAMPLE 2

Pulverizing marble, which was chosen as an example of hard material, was carried out. The rotating speed of the drum was set at 1,200 rpm, and granules of about 80-100 mesh size were obtained in about three seconds. The diameter of the perforations in the casing was 10 mm. A good result was also obtained by intermittent operation with perforations of 5 mm in diameter, the apparatus producing fine particles. Thus it was ascertained that a material having relatively high hardness or low tenacity can be effectively treated in a simple way without producing a rise of the temperature of the material due to the continuous operation.

The product thus obtained can be used as material which is mixed with resinous material to form artificial stone or floor or wall material, which is superior in appearance and durability to similar prior art materials.

EXAMPLE 3

A test was carried out on toys or household articles made of plastic material such as hard polyvinyl chloride material. The rotating speed of the drum was set at 750 rpm and granules of 50-60 mesh size were obtained in about three seconds. The diameter of the perforations in the casing was 10 mm. This test was made to crush waste articles into granular form so that the uniformity or the shape of the granules obtained was not of interest.

This test was carried out only for the purpose of testing the processing of waste articles made of synthetic resinous material, the amount of which in dust form has recently increased and presented a difficult problem in the processing of the dust. It has been found that such waste material thus crushed can be discarded as it is, without the necessity of burning or pressing, since the crushed material has substantially the same size as sand particles. It may also be used as material which is mixed with asphalt or cement material to produce a colorful pavement, floor or the like.

It will be understood that the present invention provides a multi-purpose crushing device which has a very simple construction, and is durable in continuous operation, and which can effectively crush hard material as well as tenacious material, particularly asphalt.




<- Previous Patent (METHOD FOR PNEUMATIC...)   |   Next Patent (SPRAYING APPARATUS) ->