Directional oil delivery for a chain saw bar

Abstract

Embodiments include a chain for a chain saw, the chain equipped with one or more oil channels elongated along the length of the chain. Each oil channel receives oil at a first end, the oil exiting the oil channel at an oil exit at a second end of the oil channel. The oil exit of one of the channels is positioned along a side of a chain link through which the saw chain is elongated, proximate to a cutting region of the chain to lubricate the saw chain just prior to the cutting region. A second channel can have an oil exit proximate to a nose of the chain to lubricate a sprocket in the nose of the chain.

Description

[0001] Cross-references to related applications This application claims priority to U.S. Application 17 / 524,543, filed November 11, 2021, entitled "Directional Oil Delivery for a Chainsaw Saw Bar," and U.S. Application 17 / 524,543 claims priority to U.S. Provisional Application 63 / 113,098, filed November 12, 2020, entitled "Directional Oil Delivery for a Chainsaw Saw Bar," the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] This disclosure relates to the field of power tools such as chainsaws, and more particularly to systems and methods for directional oil delivery to chainsaw shanks. Background Technology

[0003] A chainsaw typically consists of a power unit that drives a sprocket. The sprocket, in turn, drives a chain with multiple cutting teeth. The chain extends around the periphery of a slender but relatively flat bar, usually with a second sprocket located at its nose, away from the power unit. The bar and the chain form a cutting assembly, which is applied to a workpiece for cutting. The chain typically moves at high speed around the periphery of the bar and is subjected to significant pressure during cutting, which, in the absence of lubrication, can lead to significant friction and rapid damage to components. Therefore, most chainsaws are lubricated in the form of bar oil or another suitable lubricant, supplied by the power unit. As the bar oil is applied to the moving chain, which in turn is applied to the workpiece, the bar oil is continuously lost with the use of the chainsaw, thus requiring periodic replenishment. Attached Figure Description

[0004] The embodiments will be readily understood by reading the following detailed description in conjunction with the accompanying drawings. In the drawings, embodiments are shown by way of example rather than limitation.

[0005] Figure 1 The image shows a cross-section of an exemplary chainsaw bar according to various embodiments, illustrating the internal oil passages for directional oil delivery.

[0006] Figure 2 According to various embodiments Figure 1 A close-up cross-sectional view of an exemplary chainsaw bar, showing the internal bar structure and oil passages for delivering oil to the nose sprocket.

[0007] Figure 3 According to various embodiments Figure 1 and Figure 2 A cross-sectional view of an exemplary chainsaw bar, showing the laminated layers of the bar.

[0008] Figures 4A to 4E These are a series of perspective and sectional views of alternative arrangements of oil passages in solid rods according to various embodiments.

[0009] Figures 5A to 5G , Figures 5H-1 to 5H-2 These are a series of cross-sectional views of the oil outlet of a solid rod according to various embodiments, for example... Figures 4A to 4E One of the arrangements.

[0010] Figure 6A This is a cross-sectional view of a second exemplary chainsaw bar according to various embodiments, which shows another possible arrangement of the oil passage for directional oil delivery.

[0011] Figure 6B According to various embodiments Figure 6A A close-up illustration showing the details of the arrangement of oil channels for directional oil delivery.

[0012] Figure 7A This is a close-up perspective view of an exemplary elongated oil port that guides oil flow from the power head filler to a central channel in the chainsaw bar, according to various embodiments.

[0013] Figure 7B According to various embodiments Figure 7A A perspective view of an exemplary elongated oil port, showing the path of oil inflow from the port to the central channel.

[0014] Figure 8 This is an operation flowchart of a method for producing a chainsaw bar with directional oil delivery according to various embodiments. Detailed Implementation

[0015] In the following detailed description, reference is made to the accompanying drawings, which form part of the description and are illustrated in the drawings by way of exemplary embodiments that can be implemented. It should be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the invention. Therefore, the following detailed description should not be considered limiting, and the scope of the embodiments is defined by the appended claims and their equivalents.

[0016] Various operations may be described in a manner that helps to understand the embodiments as a series of discrete operations; however, the order of description should not be interpreted as implying that these operations are sequentially related.

[0017] The description may use perspective-based descriptions, such as top / bottom, back / front, and top / bottom. This description is for ease of discussion only and is not intended to limit the application of the disclosed embodiments.

[0018] The terms “coupling” and “connection”, as well as their derivatives, may be used. It should be understood that these terms are not intended to be synonyms. Specifically, in a particular embodiment, “connection” may be used to indicate that two or more elements are in direct physical contact with each other. “Coupling” may mean that two or more elements are in direct physical contact with each other. However, “coupling” may also mean that two or more elements are not in direct contact with each other, but still cooperate or interact with each other.

[0019] For descriptive purposes, phrases of the form "A / B" or "A and / or B" represent (A), (B), or (A and B). For descriptive purposes, phrases of the form "at least one of A, B, and C" represent (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C). For descriptive purposes, phrases of the form "(A)B" represent (B) or (AB), meaning that A is an optional element.

[0020] The description may use the term "embodiment" or "multiple embodiments," each term referring to one or more identical or different embodiments. Furthermore, the terms "comprising," "including," "having," etc., used with respect to embodiments are synonymous.

[0021] In a typical chainsaw, the bar is lubricated / oiled by the saw's power head, either by an oil tank on the power head or by an oil tank located away from the power head, and delivered via conduits. The lubricant is typically a relatively high-viscosity petroleum-based bar oil, or in some applications, grease. The lubrication mechanism typically pumps oil continuously into one or more oil holes at the rear of the chainsaw bar, where the bar is attached to the saw's power head, which fills grooves or channels around the bar's perimeter with oil. For safety and operability reasons, the chain on most chainsaws departs from the power head at the top of the bar, travels around the nose of the bar, is typically guided by a sprocket in the bar wall, and returns to the power head along the bottom of the bar. As the chain moves around the bar's perimeter, grooves are located directly beneath and covered by the chain, allowing the chain to pick up oil and carry it around the nose to the bottom of the bar, where the primary cutting area is located. Therefore, to ensure adequate lubrication of the entire bar and nose sprocket, one or more oil holes in existing chainsaw bars are in fluid communication with the beginning of a groove at the top of the bar, where the chain leaves the power head, so that theoretically the chain delivers oil throughout the bar. Lubrication of the bar perimeter helps keep the bar temperature at an acceptablely low level during operation, which also helps minimize bar wear. Generally, higher temperatures in a given section or assembly are associated with greater potential wear. High temperatures can be a sign of insufficient lubrication and a corresponding increase in friction, which in turn can lead to accelerated wear.

[0022] At the cutting zone at the bottom of the bar, both the bar and chain are subjected to high pressure and friction as the saw cuts, as the chain is pressed downwards into the bottom of the bar to cut the workpiece. Proper lubrication of this area is crucial for maximizing the lifespan of the chain and bar, as this area is furthest from the power head in terms of chain travel distance, and therefore furthest from the point where oil is supplied to the chain and bar. Without proper lubrication, the temperature in the cutting zone can rise to levels that cause rapid wear on the bar and saw chain. To ensure proper lubrication of all parts of the chain and bar, the sprocket at the bar nose, and especially the cutting zone, a relatively large amount of oil must be supplied to the oil holes, relying on the chain and its movement on the grooves to distribute the oil to all necessary parts. Depending on the type of saw (e.g., a handheld chainsaw or a commercial harvester with a remotely powered / operated saw head), this lubrication may be provided continuously during sawing operation, or at discontinuous or intermittent intervals, such as at the beginning of each cutting cycle. Other types of machines, including those other than saws, may provide the necessary lubrication continuously or intermittently, depending on the specific needs of the given machine.

[0023] While this method of filling the bar groove with oil is effective in maintaining chain and bar lubrication, it is potentially wasteful and environmentally harmful. Despite using relatively high-viscosity bar oil, as the chain moves around the bar, the centrifugal force generated by the chain and the rotation of the sprocket at the nose cause oil to be thrown out of the bar's nose before reaching the cutting area. This oil-throwing effect can be exacerbated by the need for a larger volume of oil to ensure sufficient oil remains at the bottom of the bar, which itself requires a larger volume of oil to compensate for the oil-throwing effect. Further oil loss occurs when the bottom of the chain and bar contacts the workpiece, and oil is transferred to the workpiece being cut. In some cases, the lubrication mechanism can be speed-adjusted proportionally to the saw speed to avoid over-lubrication at low speeds, thus reducing losses during chainsaw idling. However, when the chainsaw is operating at its working speed or during cutting, variable-speed lubrication mechanisms do not significantly reduce oil loss. For operators using chainsaws extensively, the known oil consumption of bar lubrication systems can become a significant expense and cause unnecessary environmental pollution.

[0024] To improve oil efficiency, the disclosed embodiments include a rod having a structure that allows the formation of closed oil channels within the rod body, communicating with different points on the rod. By supplying oil into the oil channels at points other than the start of chain travel, oil can be supplied directly to specific locations on the rod, and potentially to multiple points relatively simultaneously, such as the nose sprocket, the cutting area, areas identified as typically having the highest temperatures during chainsaw operation, and / or any other areas identified as experiencing increased temperature and / or pressure. Because the oil channels allow oil to be supplied directly to the nose sprocket and the cutting area, the amount of oil introduced at the start of chain travel can be significantly reduced, as there is no need to rely on the chain to deliver sufficient oil around the entire rod perimeter. Therefore, a smaller amount of oil can be more evenly distributed throughout the chain's travel path around the rod, or delivered closer to areas with high potential wear, such as the nose sprocket and / or the cutting area. Thus, damage to the rod nose due to excessive oil can be reduced or potentially avoided.

[0025] The embodiments described herein provide an overall oil consumption reduction of 20% to 60%, for example, 30% to 50%, for chainsaw systems. In a particular example, a chainsaw having a bar configured for directional oil delivery, such as one of the bars in the embodiments disclosed herein, achieves a reduction in lubricant usage of approximately 30% to 35%, while maintaining a wear amount comparable to that of conventionally oiled bars (e.g., at a single point at the start of the saw chain's travel around the bar). In addition to providing a reduction in overall oil consumption, the embodiments described herein provide a reduction in bar wear of up to 75% to 85% and a reduction in saw chain stretch (a form of wear, such as that caused by frictional wear between saw chain links) of up to 15% to 25%. These reductions are achieved at a flow rate of approximately 25% of that used for conventionally oiled bars. Therefore, the disclosed embodiments allow for reduced flow rates, for example, by 20% to 60%, while still achieving a wear amount comparable to that seen in conventionally oiled bars, thereby maintaining the normal expected lifespan of the bar and saw chain while achieving significant oil consumption savings. Alternatively, the disclosed embodiments can be used with a lubrication system that delivers oil at a conventional lever rate to achieve significantly lower wear, thereby potentially extending the life of the lever and saw chain. Furthermore, in some embodiments, a trade-off can be achieved between a moderate reduction in oil consumption and a moderate increase in lever and saw chain life. These parameters can be adjusted as needed to maximize cost savings, balancing the costs of lever oil, lever replacement, and saw chain.

[0026] Furthermore, in some embodiments, the oil passages may be fitted with one or more temperature-sensitive valves. As the bar heats up during use, the oil demand on the bar increases. Temperature-sensitive valves within the bar allow for a lower oil delivery when the bar is cold, but can open to gradually increase the oil flow as the bar heats up. Using temperature-sensitive valves on multiple channels allows for selective increases in oil flow, as different parts of the bar heat up at a greater rate than others. The use of valves also helps conserve oil when the chainsaw is not in use, as the valves can close in response to a drop in bar temperature, thus retaining oil within the passages and preventing oil from draining through the bar due to gravity or potential pressure when the chainsaw is not in use. Additionally, depending on the valve construction, some passages through the bar can be selectively opened or closed, allowing the bar to be removed and flipped (e.g., the top rail becomes the bottom rail with the cutting zone) to help even out wear. Regardless of the bar's orientation, these valves control the delivery of oil to the desired locations. For example, using gravity-repositioned spool valves, the oil passages can open or close to ensure that lubricant flows primarily to the cutting zone and the top of the nose sprocket, regardless of which side of the bar is positioned as the cutting zone.

[0027] Although embodiments are described in the context of lubrication, particularly for conveying bar oil or chain oil, it should be understood that the disclosed embodiments can be used to convey a wide variety of different types of fluids, including fluids other than oil. Examples of other types of fluids may include coolants and cooling fluids, abrasives or fluids carrying abrasives, fuels, water, synthetic fluids, synthetic or mixed lubricants, solvents, cleaning fluids, or any other fluid that can be used to convey along a structure similar to a chainsaw bar. The reader should understand that when oil is discussed herein, any of the aforementioned fluids may be used in place of oil.

[0028] Figure 1 The internal structure of a chainsaw bar 100 according to one possible embodiment is shown. The bar 100 includes a first oil (or fluid) port 102 and a second oil (or fluid) port 104. The first oil port 102 is in fluid communication with a first oil (or fluid) passage 106, and the second oil port 104 is in fluid communication with a second oil (or fluid) passage 108. A sprocket may be mounted in the nose 110 of the bar 100. A bar groove 116 extends around the periphery of the bar 100, through which a portion of the saw chain may pass. Two parallel tracks may be formed at the top of the bar groove 116, on which the saw chain slides. In a typical embodiment, the bar 100 is mounted on a saw power head (not shown) that includes a mechanism for supplying oil or another suitable fluid to the first oil port 102 and / or the second oil port 104. This mechanism may be a pump and / or reservoir, or another suitable mechanism for fluid delivery known in the art and suitable for a given embodiment.

[0029] As described above, the nose 110 typically includes a sprocket (not shown) mounted or fixed to a radial bearing. This sprocket engages with the saw chain and helps reduce friction and the resulting wear on the chain and bar as the saw chain passes through the U-shaped portion of the nose 110. Due to the sprocket's position on the bar and its proximity to the cutting area 118, the sprocket is susceptible to dust and debris, thus requiring lubrication to prevent overheating, jamming, and / or excessive wear due to dust and debris. In the depicted embodiment, each of the first oil passage 106 and the second oil passage 108 extends along the length of the bar 100 to deliver oil directly to or near the nose 110 and the sprocket. Oil (or some other suitable fluid) flowing through the first oil passage 106 exits the passage at the first oil (or fluid) outlet 112, and oil flowing through the second oil passage 108 exits the passage at the second oil (or fluid) outlet 114. In this configuration, lubricating oil or another suitable fluid is delivered to the nose 110 and any sprockets attached to the nose 110, as well as the cutting area 118 of the rod and rod groove, regardless of the orientation of the rod in use or if it is flipped by the operator, to help distribute wear more evenly around the rod.

[0030] In some embodiments, where the first oil passage 106 and the second oil passage 108 are not interconnected, the power head can be configured to deliver two different fluids: one fluid is delivered to the first oil (or fluid) orifice 102 for delivery through the first oil (or fluid) passage 106, and a second different fluid is delivered to the second oil (or fluid) orifice 104 for delivery through the second oil (or fluid) passage 108. For example, oil can be delivered to the first oil passage 106, which can be discharged through the first oil outlet 112. Figure 1 As shown, the first oil outlet 112 can be positioned such that the saw chain delivers fluid from the first oil outlet 112 to the nose 110 to lubricate the connected sprocket (not shown). A second fluid, such as an abrasive cutting fluid or a coolant, can be delivered to the second fluid passage 108, which can be discharged through the second fluid outlet 114. Figure 1 As shown, the second fluid outlet 114 can be positioned such that the saw chain delivers fluid from outlet 114 to the cutting zone 118, where the fluid can enhance cutting and / or cool the cutting zone 118 to extend the life of the bar and chain. In some embodiments, the oil from the first oil outlet 112 can be compatible with the fluid from the second fluid outlet 114, such that the cutting zone 118 is both lubricated and cooled. In other embodiments, different fluids can both be lubricants, where one type of lubricant is designed to minimize wear and maximize the function of the rotating sprocket, while another type of lubricant is designed to cool and minimize wear on the cutting zone 118.

[0031] Although in the illustrated embodiment, the first oil passage or fluid channel 106 and the second oil passage or fluid channel 108 are primarily straight and extend the length of the bar generally or substantially parallel to its longitudinal axis, this should not be considered a limitation. Other embodiments may have more or fewer (e.g., one) channels. In some embodiments, each channel may have multiple oil or fluid outlets along the length of the bar 100, for example, reaching one or more points in the bar groove 116 to provide lubrication to the saw chain. For example, the second oil passage 108 may include one or more additional oil outlets along the length of the bottom of the bar 100 to provide additional lubrication near the cutting area 118. In other instances, both the first oil passage 106 and the second oil passage 108 may include additional oil outlets along the length of the bar 100 to accommodate an operator fixing either long side of the bar downwards, thereby providing the cutting area 118 on the top or bottom edge. In this embodiment, the oil outlets may include gravity-based valve mechanisms such that only the bottom-oriented edge with the cutting area 118 is supplied with additional oil.

[0032] The oil outlet or fluid outlet can be positioned to deliver oil near the sliding interface, such as at the top of the groove 116 where the saw chain contacts the guide rail. Delivering oil to the bottom of the groove 116, rather than the sidewalls, and closer to the sliding interface, further helps avoid potential blockages caused by debris that could get stuck and / or accumulate at the bottom of the groove. While the saw chain is more likely to clean the sidewalls of the groove 116 as it travels around the bar perimeter, it may not extend to cleaning the bottom of the groove 116. Therefore, positioning the oil outlet near the sidewalls of the groove 116 helps ensure consistent oil delivery without being obstructed by debris. Furthermore, delivering oil near the sliding interface at the edge of the bar 100 helps ensure that most of the delivered oil reaches the sliding interface and the rivet engagement on the saw chain, whereas delivering oil to the bottom of the groove might require increased lubrication delivery because the groove 116 needs to be filled before the oil reaches the sliding interface and the saw chain.

[0033] Figure 2 This is a close-up of the nose 110 of an exemplary rod 100, showing the construction of the rod 100. In the illustrated embodiment, the rod 100 is manufactured as a laminate having at least three layers. Two outer layers 202 defining a first side 202a and a second side 202b are welded, bonded, riveted, fastened, or otherwise suitablely attached to either side of an inner core 204. In an embodiment, the sides of the inner core 204 define a peripheral edge 208 that forms the bottom of a rod groove 116. Due to Figure 2This is a cross-sectional view, therefore only one outer layer 202 is shown; a second outer layer 202 will cover the inner core 204 to form a sandwich structure. In the depicted embodiment, first and second channels 106 and 108 are formed in the inner core 204, which is sealed by the attachment of the outer layer 202. Furthermore, a saw chain 206 is shown, a portion of which extends into the bar groove 116. The portion of the saw chain 206 extending into the bar groove 116 can be configured to pick up any lubricant present in the bar groove 116 and carry it along the groove to help distribute the lubricant evenly. In an embodiment where an oil outlet is provided along the sidewall of the bar groove 116, the interaction of the portion of the saw chain 206 located within the bar groove 116 can pick up oil from the oil outlet and deliver it toward a guide rail at the top of the bar groove 116.

[0034] Depending on the direction of the oil outlets 112 and 114, oil can be picked up by the rotating sprocket in the nose 110 and distributed on the rotating sprocket by its rotation. In some embodiments, the sprocket itself may include features or channels to help guide the oil flow leaving the oil outlets 112 / 114 to high-friction areas in the nose 110, including the rod rail and any sprocket support surfaces. As indicated by the arrow, the saw chain 206 extends beyond the top of the rod away from the power head ( Figure 2 (not shown on the left side), around the nose 110, and toward the cutting area 118 ( Figure 1 (As shown) Return. Similarly, a set of smaller arrows starting from the first channel 106 illustrates the flow of lubricating oil along the first channel 106 and out through the first outlet 112. In this configuration, the first outlet 112 exits just before the nose 110. The saw chain 206 picks up this oil and helps distribute it around the sprocket mounted in the nose 110. The second outlet 114 exits just before the cutting zone 118, helping to provide sufficient lubrication along the cutting zone 118 to the bar groove 116, particularly to the guide rail at the top of the bar groove 116 that contacts the saw chain 206. It should be understood that the oil flow from the second channel 108 to the second outlet 114 is substantially the same as the oil flow from the first channel 106. In some embodiments, particularly when the size of the assembly is relatively large (e.g., a commercial harvester) and the oil volume may be considerable, the outlets may be configured such that the oil is delivered approximately along the center of gravity of the bar to help maintain the balance of the saw / cutting assembly.

[0035] In the cutting area 118 ( Figure 1As those skilled in the art will understand, when the saw is cutting, the track and saw chain 206 are subjected to relatively high pressure because the saw chain 206 is pressed between the workpiece and the track of the bar groove 116. This increased friction typically increases the temperature of the bar 100 in the cutting zone 118, making adequate lubrication in the cutting zone 118 crucial. Specifically, as the temperature of the bar 100 in the cutting zone 118 rises, increased lubrication is required to prevent increased wear on the bar 100 and / or the saw chain 206. In some embodiments, one or more oil outlets (including oil outlets 112 and 114) may be equipped with valve mechanisms to control the flow of oil from the outlets. In other embodiments, the valve mechanisms may be located away from or away from the respective oil outlets 112 and 114 along the first oil passage 106 and / or the second oil passage, for example, closer to the oil inlet 102 / 104. In some embodiments, the valve may include an optional functional valve or a distribution valve, wherein the oil flow to various points can be selectively closed, opened, or regulated.

[0036] The valve mechanism can be temperature-sensitive to open proportionally to the local bar temperature. In some embodiments, the temperature-sensitive region is located near the oil outlets 112 / 114. In other embodiments, the temperature-sensitive region can be located at the distal end of the oil outlets 112, 114, for example, where it is calculated that oil will be transported and deposited due to the action of the saw chain 206. In this embodiment, positioning the valve mechanism away from the oil outlets 112, 114 along the oil passages 106, 108 allows the valve to respond more accurately to temperature changes. Therefore, as the regions closer to each oil outlet or valve location increase, the valve in each region will open more, allowing more oil to flow to the region where the temperature rises. For example, as the saw is used, the temperature of the cutting area 118 rises. When the oil outlet orifice 114 is close to the cutting area 118, it will experience the temperature rise along the bar 100 at the cutting area 118. Therefore, when the cutting area 118 becomes hot, the valve located at the oil outlet 114 will allow an increased oil flow. Furthermore, it should be recognized that rod 100 can be inverted, and the arrangement of oil outlet holes 112 and 114 still functions correctly in either direction, especially when equipped with a thermal valve.

[0037] Alternatively, the thermal valve can operate in the opposite manner to the aforementioned method, for example, by reducing the viscosity of the rod oil as the rod temperature increases. In this embodiment, when the rod is cold, the thermal valve can be fully or almost fully open to ensure that a sufficient amount of viscous oil is delivered to the rod. When the rod heats up, the oil is also heated as it passes through the rod, thus thinning, reducing its resistance and increasing its flow rate. The thermal valve then closes accordingly to reduce the flow rate of the diluted hot oil, thereby preventing excessive dilution of the hot oil from flowing out.

[0038] Furthermore, valves or valve mechanisms can provide combinations of functions, such as combining thermal sensitivity with gravity actuation (as described above). This functionality can be achieved in a single valve mechanism or through a combination of valves. Such valves or combinations of valves can restrict oil flow based on temperature and cut off the oil supply when the lever is in a position allowing oil (or other fluid) to drain from the lever. In other embodiments, the valve mechanism may include a drive mechanism that can be directly driven by a signal, such as a signal from the saw's power head.

[0039] When the chainsaw is not in use, equipping each oil outlet with a valve further prevents oil leakage from the rod 100, as each valve can be substantially or completely closed when the rod 100 cools and approaches ambient temperature. In some embodiments, the valves may be configured to have a nominal or basic flow rate to ensure that the saw chain 206 and rod 100 receive initial lubrication when cold, for example, in cases where insufficient residual lubrication is determined to prevent excessive wear during initial saw startup. The flow rate can then be increased as the saw chain 206 and rod 100 rise to operating temperature. In some embodiments, in addition to or as an alternative to valves, each oil outlet 112 and 114 may be fitted with a filter or similar plug, which allows oil to flow out but prevents debris from entering the passage and causing blockage or clogging. The positioning of the filter or plug allows debris to be pushed aside by the flowing oil before entering the corresponding oil passage, where debris could otherwise become blocked and interfere with the delivery of sufficient oil. Furthermore, in response to rising temperatures, the extent to which each valve can open and / or the speed at which each valve opens can allow for adjustment of the chainsaw's oil consumption, which may come at the cost of increased component wear. Therefore, it is possible to minimize oil consumption at the expense of potentially increased component wear (better for the environment), to minimize component wear at the expense of increased oil consumption (better for the lifespan of expensive components and potentially to minimize saw downtime for component replacement), or to optimize the cost of wasted oil relative to the cost of replacing components, thereby minimizing the total cost (oil cost + replacement component cost).

[0040] Figure 3 yes Figure 2The cross-section AA shows a laminated arrangement of the rod 100 according to a possible embodiment, wherein a first outer layer 202a and a second outer layer 202b sandwich an inner core 204. These three layers can be secured by any suitable technique that allows them to be adequately connected to handle any internal pressures applied by pumping oil into the first channel 106 and the second channel 108, as well as the rod's intended operating conditions. Some welding or bonding techniques (e.g., spot welding) may be more suitable for situations where oil is pumped into the rod at relatively low pressures. Spot welding may be unsuitable because the oil pressure, combined with elevated operating temperatures, could cause oil to escape from the channels 106 and 108 between the weld points and flow into the surrounding rod groove 116. Other techniques can be employed to produce laminated structures capable of withstanding greater pressures, such as laser welding, ion beam welding, continuous resistance welding, brazing, brazing, mechanical fasteners such as rivets or screws, adhesives, and / or combinations of any of the above techniques. Other techniques, such as bonding using epoxy resin adhesives, can also be utilized.

[0041] like Figures 1 to 3 As shown, oil channels 106 and 108 are formed in the inner core 204. Oil channels 106 and 108 may be machined into the inner core prior to lamination and may penetrate the inner core completely or partially. In some embodiments, such as where one or more oil channels completely penetrate the inner core 204, the inner core 204 may be implemented as multiple components, with one or more oil channels formed by spacing between the core components relative to each other. In other embodiments, some or all of one or more oil channels may be formed in one or both of the outer layers 202a, 202b. The placement of some or all of the oil channels on the outer layer 202 or the inner core 204 may be determined based on the thickness of the material and the needs of a given implementation. The lamination configuration method allows for relatively easy formation of channels because it allows for easy machining of open channels that are subsequently sealed during the lamination process. In other embodiments, the rod 100 may be implemented as a single solid piece, with channels formed through the rod using any suitable technique. For example, the channels may be milled onto the outer surface of the rod 100. Furthermore, deeper grooves may be machined from the channels and connected to them via tubes or caps. An example of such an embodiment using a solid workpiece rod will be described herein with reference to FIG4.

[0042] Figures 4A to 4ESeveral possible embodiments are shown, corresponding to embodiments A through E respectively of a solid rod 400 with a face channel and a solid rod 450 with a groove channel, with various ways of milling the oil channel 410 into the rod. It can be seen that embodiments A and B realize channels formed or milled in the surface of each rod 400, using channels milled out of the outside of the rod 400. In embodiment A, the tube 402 is placed in the groove, or in embodiment B, the top cap 404 is placed on the groove. The rod 400 has a channel milled into its outer surface, opposite the rod groove. In embodiment A, the tube 402, configured to be milled into the shape of the channel 410, is inserted into the channel 410. The tube 402 includes an oil inlet 412 through which oil passes through the tube 402 to deliver it along the rod 400 to a distal location. In embodiment A, the oil passes through the tube 402, rather than the entire channel 410. In embodiment B, channel 410 is milled to have steps to form a deeper, narrower channel portion and a shallower, wider channel portion. A top cap 404 is then inserted into the shallower, wider channel portion, thereby closing the narrower, deeper channel, allowing channel 410 to directly conduct oil. The top cap 404 includes an inlet 412 to allow oil to flow into the deeper channel 410.

[0043] Alternatively, channel 410 may be milled within a groove, as shown by rod 450 in embodiments C, D, and E. In embodiment C, tube 452 is placed at the bottom of channel 410, and inlet 412 connects tube 452 to the outside of rod 450, allowing oil to be delivered to tube 452. In embodiment D, step 455 is milled into the side of groove 410 to accommodate top cap 454. Top cap 454 closes the bottom of groove 410, and inlet 412 delivers oil into the groove, where the oil flows beneath the top cap until it reaches outlet. In embodiment E, block 456 is inserted into the bottom of groove 410, effectively forming two narrow channels. Oil from inlet 412 can flow into one channel, over the top of block 456, and into a channel on the opposite side of the block. Embodiment E may be useful, for example, when it is desirable for the saw chain to help deliver oil along the length of the groove.

[0044] Corresponding to Examples A to H (Example H has cross-sectional views depicted in 5H-1 and 5H-2) Figures 5A to 5H-2Cross-sections of various different outlet embodiments of a solid rod are shown. In embodiment A, an external channel with insert 502 uses a curved port to deliver oil flowing through the channel to the side of the rod groove. Embodiment B shows a similar configuration, but the channel is milled within the groove. Embodiment C shows an outlet where a top cap closes the bottom of the groove, and oil flows from the closed bottom groove through an inner side insert 504 to deposit oil on the sidewall of the rod groove. In embodiment D, a block 506 is mounted at the bottom of the groove, and a gasket 508 is inserted into the inner sidewall of the groove to deliver oil from the side and top of the block to the top of the groove sidewall. In embodiment E, a top cap is placed in the groove, and two outlets 510, 512 deliver oil from the top-capped groove to the top of the rod groove, i.e., the track on which the rod slides. In embodiment F, a rod with an outer groove includes a tube 514, and an outlet 516 slopes from the tube to near the inner top of the groove. In embodiment G, similar to embodiment F, the tube is installed into an external recess, but the outlet extends straight out, exiting the side of the recess approximately halfway between the top guide rail and the bottom of the recess. Finally, embodiment H is a recess with a cap, having semi-circular cutouts 518, 520 extending from the oil passage beneath the cap to the top guide rail, a portion of which is removed to form the cutouts. Thus, the cutouts deliver oil upwards to the sidewalls of the recess and the top guide rail. In a variation, the cap may be formed as a U-shaped channel to allow the semi-circular cutouts to deliver a larger volume of oil to the top guide rail.

[0045] Figure 6A and Figure 6B Another embodiment of a rod 600 configured for directional oil delivery is depicted. The rod 600 includes a first oil port 602 and a second oil port 604, which in turn supply oil channels 606 and 608, extending along the rod 600 and generally or substantially parallel to its longitudinal axis. These structures are similar to... Figure 1 The structure described above refers to rod 100; readers can refer to the above. Figure 1 See the corresponding description for further details. The difference between rod 600 and rod 100 lies in the ends of each oil passage 606 and 608, as... Figure 6B ( Figure 6A As shown in the illustration. Figure 6B As shown, the oil passage 606 is rotated approximately 90 degrees orthogonally from the longitudinal axis of the rod 600 to form a roughly vertical channel 610 that supplies oil to the rod and rod groove just before the front sprocket.

[0046] At the bend of the oil passage 606 into the channel 610, a plug 612 may be included, which can be removed for cleaning purposes in the event that the channel 610 and / or channel 606 is contaminated with debris. In embodiments, the plug 612 may be made of an elastic compound to allow for relatively easy removal and a small amount of buffering pressure on the oil pressed into the channel 606. It should be understood that the oil passage 608 may terminate at a similar vertical channel and is similarly equipped with an elastic plug to be configured substantially mirror-image of the channels 606 and 608 and the plug 612.

[0047] Figure 7A and Figure 7B Show Figure 1 Oil holes 102, 104 and Figure 6A Oil holes 602, 602 variant embodiments. In Figure 7A In this design, an elongated oil hole 702 is formed as a channel on the outer surface 710 of the rod, for example, by milling, machining, or otherwise forming an extension on or within the outer wall attached to the inner core or center core. In some embodiments, the elongated oil hole can be formed by forming a slot or channel through the outer wall to expose the inner core, with the side surface of the inner core thus forming the bottom of the elongated oil hole. The elongated oil hole serves as a channel to guide oil downwards to an oil hole or through-hole 704, which guides the oil into an oil channel 706 through which the oil flows through the center or inner core, similar to the above description. Figure 1 The oil channel under discussion. Oil flow through the elongated oil orifice 702... Figure 7B The image is shown by dashed line 708. Equipping the rod with an elongated oil orifice 702 provides flexibility when mounting the rod to different power heads, which may have oil outlets in slightly different locations that may not be precisely aligned with the circular oil orifice, such as oil orifices 102, 104, 602, or 604. Oil can be introduced at any point along the elongated oil orifice 702, provided that the length of the orifice 702 is covered or sealed, and when pressurized, the oil will be guided into the through-hole 704 and then into the oil passage 706.

[0048] Figure 8 Operations of an example method 800 for producing a chainsaw bar with directional oil (or other fluid) delivery, according to various embodiments, are depicted, such as bar 100 or bar 600. Depending on the details and requirements of a given implementation, the operations of method 800 may be performed in the order shown or out of order. Furthermore, operations may be omitted, added, or modified according to the requirements of a given implementation.

[0049] In operation 802, one or more oil passages, such as oil passages 106 and 108, are formed on the inner core, for example, inner core 204. The oil passages can be formed using any suitable technique, such as machining or milling using mechanical, electrical, laser, chemical, or other suitable methods, or can be formed as part of the manufacture of the inner core, for example, as part of a cast or forged inner core. In some embodiments, the core can be manufactured as two or more portions and spaced apart from each other when fixed to the outer wall to form the oil passage. In other embodiments, the passage can be formed at least partially in one or both outer walls. For a given oil passage, the portion can be entirely located within the inner core, one outer wall, or a combination of the wall and the inner core. Figure 1 as well as Figure 6A and Figure 6B As shown in the embodiments, the oil passage typically extends from one end of the chainsaw bar mounted on the power head to another location on the chainsaw bar away from the sprocket end, so that oil is transported from the power head substantially along the length of the chainsaw bar.

[0050] In operation 804, an oil outlet is formed at the end of each oil passage near the sprocket end. The oil outlet can be positioned as described in one of the various embodiments described above. In one embodiment, one oil outlet can be positioned near the sprocket nose of the chainsaw bar, positioned so that the saw chain can pick up oil just before traveling around the sprocket nose, thus ensuring adequate lubrication of the sprocket. In another embodiment, another outlet can be positioned immediately after the bar travels at the sprocket nose, thereby applying and carrying sufficient lubricant to the cutting area of ​​the bar, which typically experiences the greatest wear and friction when the saw is applied to a workpiece.

[0051] In operation 806, as described above, the outer walls are secured to the side of the inner core by a suitable mechanism. The outer walls are typically larger than the inner core, such that when attached to the inner core, they extend beyond the edge of the inner core to form saw chain grooves extending around the perimeter of the rod, and at least a portion of the saw chain typically extends into these grooves. In an embodiment, the inner core also stops at the nose before reaching the outer walls, forming a cavity in which the nose sprocket rotates. Depending on the configuration of the power head, saw chain, and rod, portions of the rod, such as the portion opposite the nose of the power head where the rod engages, may have an inner core flush with the outer walls, wherein the saw chain does not run in the chain groove, for example, the chain leaves the groove to engage with the drive mechanism within the power head. Various holes may also be machined into the outer walls to provide any necessary connection points for the rod to enter the power head. Furthermore, one or both outer walls may be formed with holes or openings communicating with oil passages, allowing oil from the power head to be delivered into the oil passages within the rod.

[0052] In operation 808, the holes or openings formed in the outer wall can be elongated to accommodate different configurations of the power heads, which can vary in their position of supplying oil to the rod. This is achieved by forming the oil holes as elongated slots or grooves, such as those described above. Figure 7A and Figure 7B As seen in the image, this allows a single model of rod to be compatible with many different power heads.

[0053] Finally, in operation 810, as described above, one or more oil outlets may be fitted with valves. As mentioned above, the valves may be gravity-sensitive to prevent oil from flowing out of the downward-facing outlet, and / or heat-sensitive to regulate the flow rate based on heat and / or the viscosity of the oil. In other embodiments, in addition to or instead of valves, resilient plugs may be installed in operation 810; these resilient plugs may be removed to allow debris to be cleared from the oil passages.

[0054] Although the disclosed embodiments focus on chainsaws (e.g., handheld saws and commercial-scale machines (e.g., harvesters)), it should be understood that the directional oil delivery techniques discussed herein can be equally applied to other machines that require the delivery of lubricant to operating / working components in addition to saws.

[0055] Although certain embodiments have been shown and described herein, those skilled in the art will understand that various alternative and / or equivalent embodiments or implementations aimed at achieving the same purpose may be used instead of the shown and described embodiments without departing from the scope of the invention. Those skilled in the art will readily understand that the embodiments can be implemented in a wide variety of ways.

[0056] This application is intended to cover any modifications or variations of the embodiments discussed herein. Therefore, it is apparent that the embodiments are limited only by the claims and their equivalents.

[0057] Example The following are non-limiting examples of possible embodiments: Example 1 is a bar for a chainsaw, the bar comprising: an inner core defining a longitudinal axis, the inner core including a first side, a second side, and a peripheral edge separating the first side and the second side; a first outer wall disposed on the first side; a second outer wall disposed on the second side of the inner core, the second side being opposite to the first side; and a fluid channel formed along the longitudinal axis, the channel being in fluid communication with a fluid orifice located at a first end of the channel and a fluid outlet formed at a second end of the channel remote from the first end, wherein the first outer wall and the second outer wall extend beyond the peripheral edge of the inner core to form a bar groove, and the fluid outlet is positioned close to a cutting area of ​​the bar groove.

[0058] Example 2 includes the subject of Example 1 or some other examples in this article, wherein the fluid outlet includes a thermal valve.

[0059] Example 3 includes the subject of Example 1 or 2 or some other examples in this document, wherein the first outer wall and the second outer wall are each fixed to the inner core by laser welding, spot welding, ion beam welding or continuous resistance welding.

[0060] Example 4 includes the subject of any one of Examples 1 to 3 or some other example herein, wherein the fluid channel is a first fluid channel, the fluid orifice is a first fluid orifice, and the fluid outlet is a first fluid outlet, and the rod further includes a second fluid channel formed along the longitudinal axis, the second fluid channel being in fluid communication with a second fluid orifice located at a first end of the second fluid channel and a second fluid outlet formed at a second end of the second fluid channel, and wherein the second fluid outlet is positioned near the nose of the rod, the nose of the rod being configured to receive a sprocket.

[0061] Example 5 includes the subject of Example 4 or some other examples in this document, wherein the first fluid outlet and the second fluid outlet include thermal valves.

[0062] Example 6 includes the subject of any of Examples 1 to 5 or some other examples herein, wherein the fluid pore is elongated and is at least partially formed in one of the first outer wall or the second outer wall.

[0063] Example 7 includes the subject of any of Examples 1 through 6 or some other examples in this document, wherein the fluid channel also includes a removable elastic plug.

[0064] Example 8 includes the subject of any of Examples 1 through 7 or some other examples in this document, wherein the fluid outlet is disposed on one of the first outer wall or the second outer wall.

[0065] Example 9 includes the subject of any of Examples 1 through 8 or some other examples herein, wherein the fluid outlet is located on the periphery of the inner core.

[0066] Example 10 includes the subject of any of Examples 1 through 9 or some other examples in this document, wherein the fluid channel is formed within the inner core.

[0067] Example 11 includes the subject of any one of Examples 1 to 10 or some other examples herein, wherein the fluid passage is at least partially formed within the rod groove between the peripheral edge and the top cover, the top cover being spaced apart from the peripheral edge and spanning the rod groove between the first outer wall and the second outer wall.

[0068] Example 12 includes the subject of any one of Examples 1 to 11 or some other examples herein, wherein the fluid passage is at least partially formed within the rod groove having a tube disposed at the periphery.

[0069] Example 13 is a chainsaw comprising: a power head including an oiling mechanism; a chainsaw shank connected to the power head at a first end such that the chainsaw shank receives oil from the oiling mechanism; and a saw chain disposed around a peripheral groove of the chainsaw shank and connected to the power head such that the saw chain receives rotational motion from the power head, wherein the chainsaw shank includes: a first outer wall and a second outer wall, each of the first and second outer walls being disposed on one side of an inner core and extending beyond the peripheral edge of the inner core. The perimeter groove is defined by the first outer wall and the second outer wall and the perimeter edge; a plurality of oil passages are disposed within the inner core, each of the plurality of oil passages having a first end and a second end, the first end being configured to receive oil from the oiling mechanism, the second end terminating at an oil outlet located remotely from the first end of the chainsaw bar; and a second end receiving a sprocket that engages with the saw chain, wherein at least one of the oil outlets of the plurality of oil passages is located at a second end of the chainsaw bar near the sprocket.

[0070] Example 14 includes the subject of Example 13 or some other examples in this document, wherein the chainsaw bar includes a section located between the first end and the second end, the section being a working section, and wherein a second oil outlet of one of the plurality of oil passages is located in the working section.

[0071] Example 15 includes the subject of Example 13 or 14 or some other examples in this document, wherein each of the oil outlets includes a valve mechanism.

[0072] Example 16 includes the subject of any of Examples 13 through 15 or some other examples in this document, wherein the valve mechanism is heat-sensitive.

[0073] Example 17 includes the subject of any of Examples 13 through 16 or some other examples in this document, wherein the valve mechanism is gravity actuated.

[0074] Example 18 is a method for manufacturing a chainsaw bar, the method comprising: forming a fluid channel in an inner core having a peripheral edge defined between a first side and a second side of the inner core, the fluid channel extending between a first end and a second end of the inner core, the first end being configured to receive fluid from a fluid supply source; forming a fluid outlet at the second end of the inner core; securing a first outer wall to the first side of the inner core; and securing a second outer wall to the second side of the inner core, wherein the first outer wall and the second outer wall extend beyond the peripheral edge to define a chainsaw groove, and the fluid outlet communicating with the chainsaw groove.

[0075] Example 19 includes the subject of Example 18 or some other examples herein, and further includes forming an elongated fluid hole at the first end of the inner core in one of the first outer wall or the second outer wall, the elongated fluid hole being in fluid communication with the fluid channel.

[0076] Example 20 includes the subject of Example 18 or 19 or some other examples in this document, and also includes a removable elastic plug disposed within the fluid channel.

Claims

1. A bar for a chainsaw, comprising: The inner core defines a longitudinal axis and includes a first side, a second side, and a peripheral edge that separates the first side from the second side. A first outer wall, the first outer wall being disposed on the first side; The second outer wall is disposed on the second side of the inner core, and the second side is opposite to the first side; A first fluid channel is formed along the longitudinal axis and is in fluid communication with a first fluid orifice located at a first end of the first fluid channel and a first fluid outlet formed at a second end of the first fluid channel away from the first end. as well as A second fluid channel is formed along the longitudinal axis and is in fluid communication with a second fluid orifice located at a first end of the second fluid channel and a second fluid outlet formed at a second end of the second fluid channel away from the first end. in: The first outer wall and the second outer wall extend beyond the peripheral edge of the inner core to form a rod groove. The first fluid outlet is positioned at the perimeter edge and near the cutting area of ​​the rod groove; The first fluid outlet includes a valve; and The second fluid outlet is positioned close to the nose of the rod.

2. The rod of claim 1, wherein the valve is thermally sensitive such that the valve is configured to open as the temperature of the valve increases and close as the temperature of the valve decreases.

3. The rod of claim 1, wherein the nose of the rod is configured to receive a sprocket.

4. The rod of claim 1, wherein the first fluid hole is elongated and is at least partially formed in one of the first outer wall or the second outer wall.

5. The rod of claim 1, wherein the first fluid channel further comprises a removable elastic plug located at a corner where the fluid channel changes direction.

6. The rod of claim 1, wherein the first fluid outlet is disposed on one of the first outer wall or the second outer wall.

7. The rod according to claim 1, wherein the first fluid channel is formed within the inner core.

8. The rod of claim 1, wherein the first fluid passage is at least partially formed in the rod groove between the peripheral edge and the top cover, the top cover being spaced apart from the peripheral edge and spanning the rod groove between the first outer wall and the second outer wall.

9. The rod of claim 1, wherein the first fluid channel is at least partially formed within the rod groove, the rod groove having a tube disposed on the peripheral edge.

10. A chainsaw, comprising: The power head includes an oil injection mechanism; A chainsaw bar, the chainsaw bar being connected at a first end to the power head, such that the chainsaw bar receives oil from the oiling mechanism; and A saw chain, the saw chain being arranged around the peripheral groove of the chainsaw bar and connected to the power head, such that the saw chain receives rotational motion from the power head. The chainsaw bar includes: A first outer wall and a second outer wall, each disposed on one side of the inner core and extending beyond the peripheral edge of the inner core, the peripheral groove being defined by the first outer wall and the second outer wall and the peripheral edge. Multiple oil channels are disposed within the inner core, each of the multiple oil channels having a first end and a second end, the first end being configured to receive oil from the oiling mechanism, and the second end terminating at an oil outlet located away from the first end of the chainsaw bar. The second end, the second end accommodates a sprocket that meshes with the saw chain, and At least one of the oil outlets of one of the plurality of oil passages is located at the second end of the chainsaw bar near the sprocket and includes a valve. The valve is thermally sensitive, allowing a greater oil flow at higher temperatures compared to lower temperatures.

11. The chainsaw of claim 10, wherein the chainsaw shank includes a section located between the first end and the second end, the section being a working section, and wherein a second oil outlet of one of the plurality of oil passages is located in the working section.

12. A method for manufacturing a chainsaw bar, comprising: A fluid channel is formed in an inner core having a peripheral edge defined between a first side and a second side of the inner core. The first fluid channel extends between a first fluid orifice at a first end of the inner core and a first fluid outlet at a second end of the inner core, the first end being configured to receive fluid from a fluid supply source. A second fluid channel is formed extending longitudinally along the chainsaw bar, the second fluid channel communicating with a second fluid hole at the first end of the inner core and a second fluid outlet at the second end of the inner core, such that the second fluid outlet is located near the nose of the chainsaw bar; The first fluid outlet is formed at the second end of the inner core; The first outer wall is fixed to the first side of the inner core; The second outer wall is fixed to the second side of the inner core, wherein the first outer wall and the second outer wall extend beyond the peripheral edge to define the saw chain groove, and the first fluid outlet and the second fluid outlet communicate with the saw chain groove; as well as A valve is provided at the first fluid outlet and / or the second fluid outlet, wherein the first fluid outlet is positioned at the perimeter edge and near the cutting area of ​​the saw chain groove, and the valve is configured to substantially prevent oil leakage from the saw chain when it is not in use, and to allow oil to flow out from the provided fluid outlet when the saw chain is in use.

13. The method of claim 12, further comprising forming an elongated fluid hole at the first end of the inner core in one of the first outer wall or the second outer wall, the elongated fluid hole being in fluid communication with the first fluid channel.

14. The method of claim 13, further comprising providing a removable elastic plug within the first fluid channel.

Images