Low-speed mobile shredder with fraction size adjustment

Abstract

The low-speed mobile shredder with a frame set on a mobile base, as well as a conveyor belt (4), a working chamber (1) where working shafts (2) with blades (3) coupled with the transmission (15) are set, along with a limiter (6) and moveable grates (5) mounted rotationally with the help of gudgeon pins (14) and connected with bolts (7), is further defined in that the bolts (7) have a lug (10) with a nut (10A) which interacts with a screw (8) set in a groove (9) of the grate structure (5). In the side walls of the working chamber (1), there are pass-through holes (13) spaced out on an outline of a circle against the opening (16). Between the bolts (7), there is a spring (11) which is enclosed in a pipe (12), while the gudgeon pins (14) mounting the moveable grates (5) are set in the openings (16) in the side walls of the working chamber (1). The gudgeon pins (14) have a connecting board (14A) with pass-through threaded holes (14B).

Description

[0001] Low-speed mobile shredder with fraction size adjustment

[0002] The subject of the invention is a low-speed mobile shredder with fraction size adjustment, used to shred various types of materials, such as municipal and construction waste, pallets, debris, tree felling remains, roots, extra-large materials, etc.

[0003] Dual-shaft low-speed shredders are used to shred various types of materials, including waste materials, into fractions small enough to be recycled or disposed of using auxiliary processes. Thanks to the high quality of the material used to produce the blades, the low- speed shredder is suitable for shredding materials demonstrating different properties. There are shredding machines available which are dedicated to different parts of the waste material, and in which parallel shafts are equipped with interlaced cutting elements. The shafts are propelled in opposite directions while the interlaced elements are designed to shred the waste material by cutting. In some machines, the fraction size can be adjusted by opening or closing moveable grates which, together with a limiter, create a sieve through which only a fraction of a specific size may be sifted. The patent description US4385732 describes a waste shredding machine which includes a frame with shredding elements, as well as a feeding hopper for the processed material. With a transmission attached to the frame, both elements are supported on legs in such a way that the frame is raised above the conveyor belt. The transmission is equipped with a coupling device linked with a hydraulic engine and it is connected with a shaft equipped with cutting blades. Below the frame, there are articulated grates moved by actuators relative to their pivot point which constitutes the joint. The machine is equipped with two grates which, when closed, meet at the contact surfaces which are essentially located on the longitudinal centre line between the cutting shafts. Grates are arranged by the limiting elements. The shafts are suitably supported by outside bearing units located on the opposite end to the transmission location. Each grate includes numerous comb teeth spaced in such a way that the cutting blades embedded in the shaft interlace with the comb teeth of the grate. Moreover, the comb teeth are of such thickness that allows for a slot between each comb tooth and the neighbouring pair of cutting blades of the shaft, and the comb teeth extend radially in the direction of the shafts, when the grates are in their closed position, which allows the comb teeth to approach the spacers, preventing fibre waste from tangling with the cutting blades. Each cutting blade is formed with a pair of radially extending comb teeth with symmetrical and oppositely directed cutting edges responsible for shredding while the shafts are rotating. When the grates are closed, the blades continue shredding the waste until it its pieces are small enough to pass through the cage holes onto a conveyor belt in order to be transported to a suitable storage site. The working chamber with cutting blades and comb teeth inside can be opened from the bottom completely by enabling actuator cylinders in order to set the grates to an opened position, facilitating the waste material passage. When the grates are either in the withdrawn or completely opened position, the comb teeth are essentially withdrawn from the cutting blade path. The partially opened position of the grates is supported by manual insertion of rods through the opposite walls of the frame before the grates are moved from the completely withdrawn position. The rods rest on the surface of the grates and in such way set the comb teeth in the working position relative to the shafts as well as the cutting blades embedded in them. The essence of this invention is based on selective arrangement of the grates and the comb teeth in such a way so as to enable the machine to produce a fine product, the size of which is measured through the size of the holes in the grates, as well as a coarse product when the grates are in their partially opened position, achieved with the help of rods.

[0004] The patent description EP1304169 describes a shredder which is used especially for commercial waste and materials similar to household waste. Below the feeding hopper, there is a low-speed shredding shaft with cutting tools (blades) installed on the frame. Below the shredding shaft, there is a shredded waste collection space, e.g. in the form of a conveyor belt used to transport the shredded material. The shredding shaft interacts with the counter-cutting unit which consists of the counter-cutting tool carrier and counter-cutting elements located on it, interlacing with other counter-cutting tools. In order to adjust the spacing between the counter-cutting and shredding tools, the entire counter-cutting unit is mounted rotationally around a gudgeon pin. The cutting slot between the shredding shaft and the counter-blade unit is adjusted with the help of two wedges mounted from the side which can be moved inwards and outwards by two synchronised hydraulic actuators. The movement occurs coaxially with the shredding shaft, whereby opposite surfaces of the wedges are attached to the frame. In order to adjust the cutting slot size through rotating the entire counter-comb, the wedges are pressed constantly onto the interacting surfaces attached to the frame. In order for the wedges to be supported on the entire surface, they can be inserted cylindrically in runners and they can be rotated freely until they align with the flat support surface.

[0005] The patent application US2014103152 contains information about a bulk material shredder. The shredder includes a frame equipped with a hole, a rotating shaft which is located on the frame and is equipped with blades, as well as counter-blades which are connected with the frame and which interact with blades in order to shred the material. After shredding, the shredded material is sifted through a sieve. Depending on the sieve size, the shredded material is then discharged or transported via a drum back to the shredding space in order to be shredded once again. The access door equipped with a tilting mechanism make the inside of the shredder, especially the sieve, easily accessible. The door is located on the shredder side and it essentially seals the shredding space with the shaft inside when in the closed position. In a preferred embodiment according to the following invention, the tilting mechanism is equipped with a support used to lift and co-move the door from the bottom, as described in the closed position of the door. The placement of the counter-blades on the door allows for stable mounting of the counter-blades against the rotating blades. Additionally, such placement facilitates relatively easy access to the counter-blades by opening the door. Preferably, the door is equipped with an adjusting mechanism, the aim of which is to adjust the distance between the blade and the counter-blade. A precise setting of the distance between the blades and the counterblades facilitates shredding or cutting which can be additionally adjusted according to the necessary fraction size. The adjusting mechanism includes locking elements which mount the door against the frame when it is being operated. The mounting of the door also results in mounting the counter-blades connected to it, in relation to the drum. On the upper side, the door is equipped with a slotted hole which includes a blocking latch retaining the door in the closed position.

[0006] Grate operation with the help of actuators is a solution which increases the comfort of the machine use, but it entails the necessity of upgrading the hydraulic and electric installation of the shredder, increasing the production cost. In the majority of cases, the manual system, which is used in simple machines, bears the risk consisting in the fact that the grate system can be difficult to operate. Locking and opening requires quite a lot of force, given the size of the mechanisms and the working environment, as the grates are subjected to considerable loads. In some cases, it causes grate structure element deformations, including the locking elements. In turn, such geometry changes result in an even bigger difficulty in using the grates. Additionally, manual opening of the set of grates is hindered due to clogging up of the holes through which the shredded material is discharged, as well as due to residue present in the working chamber.

[0007] The aim of the invention is an efficient and easy-to-use manual mechanism for locking the grates which adjust the input material fraction size. The mechanism requires minimum force and basic, widely available tools from the operator.

[0008] The essence of the invention is a low-speed mobile shredder with fraction size adjustment, along with a frame secured on a mobile base, as well as a conveyor belt. The shredder includes a working chamber with working shafts to which blades coupled with a transmission are attached, as well as a limiter and moveable grates mounted rotationally with the help of gudgeon pins, connected with bolts. It is characterised in that the bolts are connected with the moveable grates in a way facilitating movement along the axis and that they have a lug with a secured nut which interacts with a screw secured in a groove of the grate structure. The screw adheres to both sides of the groove of the grate structure with flanges.

[0009] In the side walls of the working chamber, there are holes which are spaced out on an outline of a circle against the opening, and the radius of the circle is equal to the distance between the axes of the gudgeon pin and bolt.

[0010] Preferably, the holes are pass-through.

[0011] In a preferred embodiment, there is a spring enclosed in a pipe between the bolts.

[0012] In the mobile shredder, the gudgeon pins mounting moveable grates are secured in the holes in the side walls of the working chamber. Preferably, they have a connection board with pass-through threaded holes.

[0013] The placement of the screw adhering to the groove in the grate structure with flanges, interacting with the nut of the lug bolt, enables the blocking bolt to be moved with minimum force applied, utilising the screw mechanism. The placement of the spring in an enclosed pipe, between bolts of the same grate, ensures additional force extending the bolts and facilitating their movement by rotating the locking screw. The rotation axis of the grate supported on gudgeon pins which are perpendicular to threaded holes facilitates dismantling of gudgeon pins mounting the grate in case they need to be replaced due to deformation caused by overload. Pass-through holes included in the machine structure for the locking bolts facilitate loosening of the bolts with the help of a hammer in the case of their jamming.

[0014] The subject of the invention is reproduced in an embodiment in the drawing, where fig. 1 presents a perspective view of the low- speed mobile shredder, fig. 2 presents a top view of the low-speed mobile shredder, fig. 3 presents a front view of the low-speed mobile shredder, fig. 4 presents a side view of the low-speed mobile shredder, fig. 5 presents an exploded view of the mobile grate mechanism, fig. 6 presents an A-A cross-section of fig. 2, fig. 7 presents a D-D cross-section of fig. 3, fig. 8 presents a top and side view of the grate gudgeon pin, fig. 9 presents the element B showcasing the bolts with lugs and a nut interacting with the screw, fig. 10 presents a side view of the screw used to extend the bolts, fig. 11 shows an F-F cross-section of fig. 4, and fig. 12 shows an E-E crosssection of fig. 4.

[0015] In the embodiment, the low-speed mobile shredder contains a frame set on the base with the crawler drive system. The working chamber 1 and conveyor belt 4 are mounted to the frame. The working chamber 1 includes two shafts 2 with embedded blades 3. The propulsion system with the transmission 15 propels shafts 2 with blades 3. The shafts 2 with blades 3 create cutting edges along with a limiter 6 and moveable grates 5 which are mounted rotationally on gudgeon pins 14. The placement of the moveable grates 5 against the shafts 2 with blades 3 makes it possible to adjust the input material fraction size. The grate 5 is locked in the set position with bolts 7 with lugs 10 and a nut 10A interacting with the screw 8. The screw 8 is located in the groove 9 of the grate structure 5 and includes two flanges 8A which are supported on both sides of the groove of the grate structure 5. Rotation of the screw 8 causes extension of the bolt 7, and the direction of the extension depends on the direction of rotation of the screw 8. Additionally, between the bolts 7 of the same grate 5, there is a spring 11 enclosed in a pipe 12 which ensures additional force extending the bolts 7 outwards. The bolts 7 extend through walls of the working chamber 1, through holes 13. The placement of the grate 5 against the shaft 2 with blades 3, which translates into the shredded material fraction size, depends on through which holes 13 bolts 7 are extended. In case the moveable grates 5 are locked with bolts 7 using the first pair of holes 13A and 13D, the fraction size is smaller due to a greater distance from the shaft 2 with blades 3. In case the bolts 7 are extended using the second pair of holes 13B and 13C, the fraction size is larger. When operating the machine, there may occur obstacles to extending the bolts 7 and changing the placement of the moveable grates 5 (e.g. clogging up of holes through which the shredded material leaves the working chamber or deformation of grates due to overload). In such cases, it is possible to loosen the jammed bolts 7 by hitting the extending part of the pass-through holes 13 with a hammer. In the case of one of the holes 13, there is no outside access to the bolt 7 since it is hindered by the transmission 15. In such a case, one of the screws 17 of the transmission 15 should be unscrewed and a longer one should be screwed in, thanks to which the jammed bolt 7 is pushed out, pressing on the frontal area 7A. The moveable grates 5 are friction elements subjected to considerable overload. In some cases, it generates overload which causes deformation of grate structure 5 elements. They are also consumables and their replacement, given the reasons above, may be hindered. For an easier replacement of the grates 5, they are secured on gudgeon pins 14 which have threaded holes 14B on the connecting board 14A. The holes allow screwing the screw in and taking the gudgeon pin 14 out of the hole 16 in the side wall of the working chamber 1.

Claims

Claims1. The low-speed mobile shredder with a frame set on a mobile base, as well as a conveyor belt (4), a working chamber (1) where working shafts (2) with embedded blades (3) coupled with transmission (15) are set, along with a limiter (6) and moveable grates (5) mounted rotationally with the help of gudgeon pins (14) and connected with bolts (7) is characterised in that the bolts (7) are connected with the moveable grates (5) in a way that allows for their movement along the axis and they have a lug (10) with a fixed nut (10A) which interacts with a screw (8) set in a groove (9) of the grate's construction (5), the screw (8) adhering to both sides of the groove (9) of the grate's construction (5) with flanges (8A).

2. The low-speed mobile shredder, according to claim 1, is characterised in that there are holes (13) in the side walls of the working chamber (1).

3. The low-speed mobile shredder, according to claim 2, is characterised in that the holes (13) in one of the walls are spaced out on an outline of a circle against the opening (16), and the radius of the circle is equal to the distance between the axes of the gudgeon pin (14) and the bolt (7).

4. The low-speed mobile shredder, according to claim 2, is characterised in that the holes (13) are pass-through.

5. The low-speed mobile shredder, according to claim 1, is characterised in that there is a spring (11) enclosed in a pipe (12) between the bolts (7).

6. The low-speed mobile shredder, according to claim 1, is characterised in that the gudgeon pins (14) mounting the moveable grates (5) are set in openings (16) in the side walls of the working chamber (1).

7. The low-speed mobile shredder, according to claim 6, is characterised in that gudgeon pins (14) have a connecting board (14A) with pass-through threaded holes (14B).

Images