Apparatus for producing propagation pots

Abstract

The apparatus produces paper propagation pots. The apparatus is particularly suitable where the growth medium comprises relatively harder and / or tougher materials than sphagnum moss, such as coir, perlite, vermiculite, rice hulls, wood fibers, sand, composted bark, and biochar.

Description

[0001] Apparatus for producing propagation pots

[0002] Technical field of the invention

[0003] The present invention relates to the production of propagation pots.

[0004] Background of the invention

[0005] Numerous greenhouses and nurseries have traditionally relied on plastic pots for plant cultivation. This practice contributes significantly to the global increase in plastic waste. Moreover, during the harvesting of herbs, the plastic pots often remain attached to the roots and growth medium, leading to inadequate recycling of these components.

[0006] To mitigate the environmental impact of plastic use, an increasing number of greenhouses and nurseries are turning to propagation pots made of sphagnum encased in paper containers, which may feature one or two open ends. However, the growing scarcity and cost of sphagnum moss, exacerbated by overharvesting and habitat destruction, have prompted these facilities to innovate by incorporating various fillers with sphagnum moss to create sustainable growth mediums. These fillers are chosen for their water retention, aeration capabilities, and, in some cases, nutrient content. Among the commonly used fillers are coir (coconut fiber), perlite, vermiculite, rice hulls, wood fibers, sand, composted bark, and biochar.

[0007] Coir, derived from coconut shell fibrous husks, stands out as a sustainable peat moss alternative, offering superior water retention and aeration. Perlite, a type of volcanic glass, is expanded through heating to enhance medium drainage and aeration. Vermiculite, similar in function to perlite, expands upon heating and excels in water retention and nutrient release, contributing to a porous growth medium. Rice hulls, the protective covering of rice grains, ensure excellent drainage and aeration, adding bulk to the medium. Wood fibers, often used as a substitute for sphagnum moss, effectively retain moisture and structure the medium to support root growth. Composted bark, from pine or fir, and biochar, a charcoal produced from organic waste, are also integrated into the medium to improve its water and nutrient holding capacity, along with enhancing microbial life essential for plant growth. The production of these paper propagation pots involves creating continuous lengths of propagation tubes, encapsulating the growth medium in a continuous paper wrap, as e.g., outlined in patent application WO9203914. After production, these continuous lengths are cut into segments of appropriate size, matching the intended dimensions of a propagation pot. This cutting process employs specialized equipment, such as blade knives or rotary knives. However, the introduction of new filler materials presents challenges, complicating the cutting process, especially as the diameter of the propagation tubes increases. This issue underscores the need for continuous innovation in the design of cutting tools to accommodate the evolving composition of growth mediums.

[0008] GB719961 (A) discloses a method of manufacturing casts or blocks from soil, vegetable mould or like material that comprises feeding such material into an extruder comprising a casing with a worm conveyer wherein it is homogenized and from which it is driven out between the casing and a central core as a centrally perforated string which is subjected to periodical cutting parallel to the delivery end of the casing. The end of the casing is grazed by a cutting member, e.g., in the form of cutting wires radially stretched in a driven ring. By an accurate regulation of the speed of movement of the ring, pieces of the desired length will each time be cut off the cylindrical body of mould driven out of the casing.

[0009] Summary of the invention

[0010] It is an object of the present invention to provide a new solution to cut paper propagation pots from continuous lengths of propagation tubes.

[0011] The inventor of the present invention has developed an apparatus for producing paper propagation pots from continuous lengths of propagation tubes including a new cutting means in the form of a wire saw.

[0012] One aspect relates to an apparatus for producing propagation pots, the apparatus comprising:

[0013] - a separation unit adapted for separating an individual paper propagation pot from a paper propagation tube; wherein the separation unit comprises a wire saw comprising a cutting wire.

[0014] The use of a wire saw offers several advantages over existing cutting methods for cutting propagation pots from paper propagation tubes. It can cut through hard and tough materials with precision and minimal damage to the surrounding area. This makes it ideal for such a controlled cutting operation, where it is crucial to avoid damage to the paper envelope.

[0015] It is generally understood that a wire saw is continuously or reciprocally moved across a material to grind away at it until a cut is achieved.

[0016] The wire saw is preferably a continuous wire saw. The continuous wire saw is a type of wire saw characterized by its continuous loop of cutting wire, which is driven by a series of pulleys and / or wheels. This design allows for uninterrupted cutting action, making it highly efficient for the present application.

[0017] In one or more embodiments, the wire saw comprises a continuous loop of cutting wire driven by a series of pulleys and / or wheels.

[0018] The cutting wire may preferably be made of steel and coated with abrasive materials, such as diamond grit. The abrasiveness of the wire allows it to cut through hard and tough materials by abrasion. There are suitable alternatives to the preferred use of diamond as the abrasive material on the cutting wire. Silicon carbide is known for its thermal conductivity and resistance to wear, making it suitable for cutting softer stones and materials. Aluminium oxide offers good hardness and durability at a lower cost than diamond. Boron carbide stands out for being one of the hardest materials after diamond and cubic boron nitride, providing excellent wear resistance. Garnet, a natural mineral known for its hardness and sharp edges, offers a cost-effective balance of performance, and is favoured for softer materials or when a less aggressive cutting action is needed. Cubic Boron Nitride (CBN) is another suitable material that rivals diamond in hardness and surpasses it in thermal and chemical stability at high temperatures. Additionally, metals can be electroplated or sintered to hold abrasive particles in place on a wire, providing a durable bond that enhances the cutting efficiency and lifespan of the saw. The combination of metal and abrasive material can be customized to meet specific cutting requirements.

[0019] A series of wheels and / or pulleys guide the wire and provide the necessary tension to keep it taut while cutting. At least one of these wheels and / or pulleys may be motor driven to move the wire through the paper propagation tube. The motor driven wheels and / or pulleys start moving the cutting wire, which then begins to cut into the paper propagation tube. The speed and tension of the wire can be adjusted based on the growth medium’s hardness and / or toughness and the desired cut quality.

[0020] To prevent overheating and to remove cut material (slurry) from the cut line, a water or coolant system may be used. This system may e.g., spray the cutting wire and / or cutting area, keeping the temperature down and enhancing the cutting efficiency.

[0021] In the operation of a continuous wire saw, the cutting process is characterized by a division of roles within the cutting wire loop. The cutting wire may at any given time comprise a cutting segment, a return segment, a drive segment, and a guide segment. Hence, only one part of the cutting wire loop, i.e., the cutting segment, comes into direct contact with the paper propagation tube and actively engages in the cutting process. This active participation is a result of the saw's design and setup, which optimizes tension and movement to enhance cutting efficiency and precision on this specific side of the loop. The cutting segment of the wire is maintained under tension and driven against the paper propagation tube at an optimal speed. This active cutting zone is typically positioned on the downward or horizontal part of the loop, varying with the saw’s setup and the orientation of the paper propagation tube. Its primary task is to cut through the material, facilitated by the wire’s tension and the abrasive properties of its coating.

[0022] Contrastingly, the portion of the wire loop not engaged in cutting, often called the “return path” plays a supporting role. It may be divided into a return segment, a drive segment, and a guide segment. Its function is not to cut but to complete the wire’s circular motion, driven by the pulleys and / or wheels. After passing through the cutting zone, the cutting segment of the cutting wire moves back to the drive system, now changing its name to either a return segment, a drive segment, or a guide segment, depending on where on the loop it is present. Here, the wire segment may be cooled, cleaned, and / or re-tensioned before re-entering the cutting zone. This division into an active cutting zone and a return path is rooted in practical needs. It addresses the direction of force necessary for effective cutting, the removal of cut material or slurry to prevent clogging, and the maintenance of optimal temperature through cooling fluids. Concentrating the cutting action on a specific part of the wire loop allows for a more controlled and consistent cutting process, ensuring the wire saw operates efficiently and effectively.

[0023] The cutting segment may comprise a leading edge and a trailing edge. The leading edge is in the present context defined as the part of the cutting segment that first comes into contact with the paper propagation tube. Hence, this definition is independent on the cutting orientation. The trailing edge is in the present context defined as the part of the cutting segment that follows the leading edge in the cutting action, possibly playing a role in further abrading and removing material that the leading edge has already engaged.

[0024] The speed at which the wire is operated is a critical factor that influences both the efficiency of the cutting process and the longevity of the wire itself. In the present context, a speed of 35 m / s or more, such as 35-45 m / s, is considered an optimal operational speed, balancing cutting efficiency with wire wear.

[0025] In a preferred embodiment, a first produced paper propagation pot is cut from one side of the paper propagation tube, and wherein a subsequently produced paper propagation pot is cut from the opposite side of the paper propagation tube. Here, the edges of the cutting wire changes functions, i.e., one of the edges acts as the leading edge in the first operation and the other edge acts as the leading edge in the second operation. This configuration allows for a much faster cutting operation as the wire saw will not need to be moved back and forth for each operation. Furthermore, the coating of the cutting wire will be more equally worn, thereby prolonging the operational lifetime of the cutting wire.

[0026] In one or more embodiments, the wire saw is configured with reciprocal movement. An automatic wire saw with reciprocal movement is a specialized type of cutting machine that employs a wire coated with abrasive particles, as described above. Unlike the continuous loop wire saw, this saw features a mechanism that allows the wire to move back and forth across the material. This reciprocal movement helps distribute wear evenly along the wire, extend its life, and enable deeper cuts with reduced risk of wire breakage.

[0027] The core of the saw consists of a wire embedded with abrasive particles that grind away the material as the wire moves back and forth. The drive system, which includes motors and mechanical linkages, controls the speed, force, and pattern of the wire’s movement. This system may also be supported by guides and rollers that keep the wire properly aligned and tensioned, ensuring it follows a precise path during the cutting process.

[0028] An integral part of the wire saw is its computerized control system, which allows operators to set and adjust cutting parameters such as speed, and wire tension, and e.g., the stroke of the reciprocal movement. This system may also include sensors that monitor the cutting progress and automatically make adjustments to optimize performance. To prevent overheating and reduce wear on the wire, a cooling and lubrication system may also be employed, which sprays or bathes the wire in a coolant fluid, helping to remove debris from the cutting area.

[0029] In one or more embodiments, the wire saw (both types), or more general the separation unit, is configured to alternately cut the paper propagation tube from one side or the other.

[0030] In one or more embodiments, the separation unit further comprises a cutting land adapted for supporting a part of the paper propagation tube.

[0031] In the present context, the term “cutting land” refers to the designated area(s) or surface(s) of the separation unit where the cutting action is intended to take place. The suitability of such a cutting land depends on several factors, including the material of the paper propagation tube, the desired outcome of the cut (such as the shape and size of the paper propagation pot to be cut from the paper propagation tube), and the specific capabilities of the wire saw being used.

[0032] The cutting land should preferably be accessible and oriented in a way that the wire saw can be properly positioned and guided through the paper propagation tube. This might involve securing the paper propagation tube in a specific position or adjusting the saw setup. For straight cuts, the cutting land should be aligned with the desired direction of the cut, ensuring that the wire can move smoothly and straight through the material. For more complex or curved cuts, the cutting land might need to be marked or planned out in advance, considering the wire saw’s ability to follow a specified path without deviating.

[0033] In one or more embodiments, the cutting land comprises a slot adapted for receiving the cutting wire, thereby allowing the cutting wire to pass through the paper propagation tube. Preferably, the cutting land comprises a supporting zone on either side of the slot, said supporting zones adapted for supporting a part of the paper propagation tube. More preferably, at least one of the supporting zones comprises a tube or gutter adapted for receiving a part of the paper propagation tube. The tube or gutter is preferably adapted for supporting the bottom and sides of the paper propagation tube.

[0034] In some embodiments, debris may accumulate in the guide slots of the pulleys or wheels that guide and drive the wire. These guide slots are critical components as they help to align and maintain the tension of the wire during the cutting process. When these slots become clogged with debris, it can lead to misalignment, increased wear on the wire, and potential breakdowns of the machinery.

[0035] To effectively manage this problem, a scraping unit may be present, e.g., equipped with a scraper blade. This blade may be made from a hard, wear-resistant material, such as hardened steel, carbide, or specialized plastics. It is specifically designed to remove debris without damaging the pulley or wheel. The scraper blade is mounted close to the pulley or wheel, specifically at a position where the wire does not pass simultaneously. This positioning is crucial as it ensures that the cleaning action by the blade does not interfere with the operation of the wire. The scraper blade operates by pressing against the pulley or wheel with enough pressure to remove debris but not so much that it causes excessive wear. It is particularly focused on cleaning out the guide slots where debris is most likely to accumulate. A tensioning system, e.g., involving springs, may help maintain consistent contact between the blade and the pulley or wheel, allowing it to adapt to any surface irregularities and efficiently clean the slots without damaging the pulley or wheel.

[0036] As the wheel or pulley rotates, the scraper blade actively removes any material buildup from the guide slots. The debris typically falls into a collection tray or is ejected from the machine to prevent it from re-entering the cutting area. By keeping these guide slots clear, the scraping unit ensures that the wire is properly aligned and tensioned, which is crucial for precise and efficient cutting.

[0037] Brief description of the figures

[0038] Figure 1 shows a rear-view of a multi-line apparatus in accordance with various embodiments of the invention.

[0039] Figure 2 shows a front view of a multi-line apparatus in accordance with various embodiments of the invention.

[0040] Figure 3 shows a front-view of a part of a multi-line apparatus in accordance with various embodiments of the invention.

[0041] Figure 4 shows a rear-view of a part of a multi-line apparatus in accordance with various embodiments of the invention.

[0042] Figure 5 shows a rear-view of a part of a separation unit in accordance with various embodiments of the invention.

[0043] Figure 6 shows a perspective view of a part of a separation unit in accordance with various embodiments of the invention. Detailed description of the invention

[0044] Figure 1 shows a part of a multi-line (three lines are shown but in general multiple could encompass e.g., 2-100 lines) apparatus in accordance with various embodiments of the invention. Some of the components have been removed for a better view of the core components of the invention.

[0045] The apparatus 100 is shown comprising a separation unit 110 adapted for separating individual paper propagation pots 300 from paper propagation tubes 200. The separation unit 110 comprises a wire saw 120 operating with a cutting wire 122 driven by a motor unit 126 and two pulleys or wheels 124. As discussed above, the use of a wire saw offers several advantages over existing cutting methods for cutting propagation pots from paper propagation tubes as it can cut through the newly used relatively harder and / or tougher materials with precision and minimal damage to the paper envelope. The paper propagation tubes 200 are delivered (e.g., directly) / transported to the separation unit 110 on a conveyor. The paper propagation tubes 200 may be produced continuously onto the conveyor 160, or alternatively, individual paper propagation tubes 200 are positioned onto the conveyor 160, automatically, or manually. Equipment for the production of paper propagation tubes is well-known within the art and will not be discussed further.

[0046] The separation unit 110 is here mounted to a chassis 140 via a displacement unit 150 (see Figure 2). The function of the displacement unit is to move the wire saw 120 up and down relative to the paper propagation tubes 200. This configuration allows the wire saw 120 to alternately cut the paper propagation tube 200 from one side or the other, thereby increasing the production capacity. In general, the displacement unit 150 may have many different configurations but is here shown comprising a supporting frame 154 for the wire saw 120, and a mechanical mechanism for moving the supporting frame 154 up and down relative to the chassis 140. This mechanism is here shown comprising a pneumatic cylinder 152, and two guide rods 156 with corresponding linear bearing mounts 158 (see Figures 3 and 5).

[0047] Returning to the separation unit 110, it is here (see Figures 1 , 4, and 5) also shown with a specialized cutting land 130. A part of the cutting land 130 is adapted for supporting the part of the paper propagation tube 200 closest to the place where it is cut to form a paper propagation pot 300. Two supporting zones 134A, 134B are positioned on either side of a slot 132 adapted for receiving the cutting wire 122, thereby allowing the cutting wire 122 to pass through the paper propagation tube 200. Each of the two supporting zones 134A, 134B are adapted for supporting a part of the paper propagation tube 200 and are configured as tubes. This configuration secured that the paper propagation tube 200 will not deform when cut.

[0048] In Figure 6, a pulley scraping unit 128 is shown. A similar unit (a wheel scraping unit) may be arranged in connection with the wheel. The pulley or wheel scraping unit 128 may comprise a scraper blade mounted close to the pulley or wheel, specifically at a position where the wire does not pass simultaneously. This positioning is crucial as it ensures that the cleaning action by the blade does not interfere with the operation of the wire. The scraper blade operates by pressing against the pulley or wheel with enough pressure to remove debris but not so much that it causes excessive wear. It is particularly focused on cleaning out the guide slots where debris is most likely to accumulate.

[0049] References

[0050] 100 Apparatus

[0051] 110 Separation unit

[0052] 120 Wire saw

[0053] 122 Cutting wire

[0054] 124 Pulley or wheel

[0055] 126 Motor unit

[0056] 128 Pulley scraping unit

[0057] 130 Cutting land

[0058] 132 Slot

[0059] 134 Supporting zone

[0060] 140 Chassis

[0061] 150 Displacement unit

[0062] 152 Pneumatic / hydraulic cylinder

[0063] 154 Supporting frame

[0064] 156 Guide rod

[0065] 158 Linear bearing mount

[0066] 160 Conveyor

[0067] 200 Paper propagation rod

[0068] 300 Paper propagation pot

Claims

Claims1. An apparatus (100) for producing paper propagation pots (300), the apparatus (100) comprising:- a separation unit (110) adapted for separating an individual paper propagation pot (300) from a paper propagation tube (200); characterized in that said separation unit comprises a wire saw (120) comprising a cutting wire (122).

2. The apparatus (100) according to claim 1 , wherein the wire saw (120) comprises a continuous loop of cutting wire (122) driven by a series of pulleys and / or wheels (124).

3. The apparatus (100) according to claim 2, wherein the wire saw (120) is configured to alternately cut the paper propagation tube (200) from one side or the other.

4. The apparatus (100) according to any one of the claims 1-3, wherein the separation unit (110) further comprises a cutting land (130) adapted for supporting a part of the paper propagation tube (200).

5. The apparatus (100) according to claim 4, wherein the cutting land (130) comprises a slot (132) adapted for receiving the cutting wire (122), thereby allowing the cutting wire (122) to pass through the paper propagation tube (200).

6. The apparatus (100) according to claim 5, wherein the cutting land (130) comprises a supporting zone (134A, 134B) on either side of the slot (132), said supporting zones (134A, 134B) adapted for supporting a part of the paper propagation tube (200).

7. The apparatus (100) according to claim 6, wherein at least one of the supporting zones (134A, 134B) comprises a tube or gutter adapted for receiving a part of the paper propagation tube (200).

8. The apparatus (100) according to any one of the claims 1-7, further comprising a water or coolant system adapted for preventing overheating and to remove cut material (slurry) from the cut line.

9. The apparatus (100) according to claim 8, wherein the water or coolant system is adapted to spray the cutting wire and / or cutting area, thereby keeping the temperature down and enhancing the cutting efficiency.

10. The apparatus (100) according to any one of the claims 1-9, further comprising a displacement unit (150) adapted to move the wire saw (120) up and down relative to the paper propagation tube (200).

11. The apparatus (100) according to any one of the claims 1-10, further comprising a pulley scraping unit (128) and / or a wheel scraping unit.

12. A system comprising multiple lines of apparatuses (100) in accordance with any one of the claims 1-11.

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