Patent Publication Number: US-3971277-A

Title: Intermittently operable rotary chopping apparatus for matted fibrous material

Description:
This invention relates generally to rotary choppers, and more particularly to a rotary chopper for relatively thick matted fibrous material. 
     An object of the invention is to provide a rotary chopper for matted fibrous material, the chopper being operable intermittently through one turn to chop off a selected length of the matted fibrous material. 
     Another object is to provide a rotary chopper for matted fibrous material including elevating and compressing means for the material adjacent a chopping blade, whereby mats with end surfaces substantially planar and perpendicular to top and bottom surfaces are produced. 
    
    
     Other objects and advantages will become apparent when the following specification is considered along with the accompanying drawings in which: 
     FIG. 1 is a side elevational view of a rotary chopper constructed in accordance with the invention, with portions omitted for clarity; 
     FIG. 2 is a top view of the rotary chopper of FIG. 1; 
     FIG. 3 is a sectional view taken generally along the line 3--3 of FIG. 2; 
     FIG. 4 is a fragmentary view taken from the lefthand side of FIG. 3; 
     FIG. 5 is an enlarged fragmentary sectional view taken generally along the line 5--5 of FIG. 2 and showing a chopping blade of the rotary chopper in its normal, at-rest position; and 
     FIGS. 6-8 are views similar to FIG. 5 but showing progressive movement of the chopping blade to the chopping position of FIG. 8. 
    
    
     With reference to the drawings, a rotary chopping apparatus 10 constructed in accordance with the invention is illustrated in FIGS. 1 and 2. The apparatus 10 includes a framework 12 to which a plurality of brackets (not shown) are secured for supporting a motor 14, a clutch and brake shaft 16, an intermediate drive shaft 18, a chopping blade shaft 20, and a back-up roll shaft 22. A shaft 24 is mounted in its own framework (not shown) and supports a front roller 25 of a feed conveyor having an endless belt 26. Similarly, a shaft 28 is mounted in a framework (not shown) receivable within the framework 12 and supports a rear roller 29 of a discharge conveyor having an endless belt 30. 
     The motor 14 continuously rotatably drives a gear 32 mounted on its output shaft. The gear 32 continuously drives a timing belt 33 and a flywheel gear 34 rotatably mounted on the shaft 16 adjacent one end thereof and operatively associated with a clutch mechanism 36. A brake mechanism 38 is operatively associated with the shaft 16 adjacent the other end thereof. Preferably the clutch mechanism 36 and the brake mechanism 38 are pneumatically operable under the control of solenoid operated valves (not shown). Two sprockets 40 are fixedly mounted respectively on extreme opposite end portions of the shaft 16 and are operatively connected respectively to two sprockets 42 fixedly mounted respectively adjacent opposite ends of the shaft 18 by a pair of roller chains 43. Two sprockets 44 are fixedly mounted respectively on extreme opposite end portions of the shaft 18 and are operatively connected respectively to two sprockets 46 fixedly mounted respectively on opposite end portions of the shaft 20 by a pair of roller chains 47. 
     As best shown in FIGS. 5-8, the portion of the shaft 20 within the framework 12 is reinforced by a concentric hollow shaft 50 secured at opposite ends to the shaft 20. A blade holding member 52 is welded to the outer surface of the hollow shaft 50. The member 52 is substantially collinear with the shaft 50 and extends radially therefrom. An outer end portion of the member 52 is recessed on one side and has a chopping blade 54 secured to that side by a clamping bar 56 held in position by a plurality of screws 57, only one of which is shown, threaded into a nut strip 58 on the opposite side. A plurality of braces 60, only one of which is shown, are welded to the shaft 50 in spaced relationship axially thereof and to the member 52 on the side thereof having the nut strip 58. A curved sheet metal cam 62 having a bent portion under the nut strip 58 has an opposite end portion secured to the shaft 50 by a plurality of screws 64, only one of which is shown. A hollow steel back-up roll 66 having a rubber sleeve 67 bonded thereto is secured at opposite end portions to the shaft 22. The shaft 22 is rotatably driven continuously by an appropriate motor, shafts, sprockets, and roller chains (not shown). 
     A sprocket 70 (FIGS. 1 and 2) on the shaft 20 is operatively connected to a sprocket 72 by a roller chain 73. The sprocket 72 is fixedly mounted on a shaft 74 (FIG. 3) rotatably mounted in a pair of bearing blocks 75 and 76 secured to the framework 12. A flat metallic flag 78 is secured to an end of the shaft 74 opposite the sprocket 72 and against a collar 79 on the shaft 74 by a screw 80. A proximity switch 82 is secured to a bracket 83 depending from the framework 12 and is operatively associated with the flag 78. 
     OPERATION 
     Matted fibrous material 84 is formed by a continuous process upstream of the rotary chopping apparatus 10 and fed thereto by the endless belt 26 of the feed conveyor. A pulse generator (not shown) may be operatively connected to a shaft of the feed conveyor system and to a counter (not shown) which effects the disengagement of the brake mechanism 38 and engagement of clutch mechanism 36 at a preselected pulse count determinative of the length of the chopped-off mats. The motor 14 continuously drives the flywheel gear 34, and when the brake mechanism 38 is disengaged and the clutch mechanism 36 is engaged, the shaft 16 is rotated. The sprockets 40 then drive the sprockets 42, shaft 18, sprockets 44, sprockets 46, and shaft 20 to chop off a mat of the selected length from the matted fibrous material 84, the mat being carried away by the endless belt 30 of the discharge conveyor. The shaft 20 also drives the sprocket 70, sprocket 72, shaft 74, and flag 78. As the flag 78 passes by the proximity switch 82, the activation of the switch 82 effects the disengagement of the clutch mechanism 36 and the engagement of the brake mechanism 38, a time delay being provided to enable the flag 78 to clear the switch 82 so as not to prevent subsequent engagement of the clutch mechanism 36 and disengagement of the brake mechanism 38 under the control of the counter (not shown). The disengagement of the clutch mechanism 36 and engagement of the brake mechanism 38 stops the rotation of the shaft 16, the shaft 20 being stopped with the chopping blade 54 in the position shown in FIG. 5. 
     As shown in FIG. 1, the upper portion of the back-up roll 66 with the rubber sleeve 67 is above plane of support afforded by the upper portions of the endless belts 26 and 30, and the matted fibrous material 84 is thus raised up as it passes over the back-up roll 66. As the chopping blade 54 moves from its rest position of FIG. 5 to its chopping position of FIG. 8, the cam 62 compresses the material 84 a considerable amount before the chopping blade is operatively engaged with the rubber sleeve 67 on the back-up roll 66. After the chopping operation, the end portions of the chopped-off mats substantially resume their original thickness. Both the elevating of the material 84 by the back-up roll 66 and the compressing thereof by the cam 62 ahead of the chopping blade 54 result in substantially square ends on the chopped-off mats after the end portions resume their original thickness. The end surfaces on the chopped-off mats are thus substantially planar and substantially perpendicular to the top and bottom surfaces of the mats after the end portions resume their original thickness. 
     Various modifications may be made in the structure shown and described without departing from the spirit and scope of the invention as set forth in the following claims.