Patent Publication Number: US-2022219350-A1

Title: Saw chain link with one or more oversized rivet holes

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to co-pending U.S. patent application Ser. No. 15/406,602, filed Jan. 13, 2017, which in turn claims priority of U.S. Provisional Patent Application No. 62/278,331, filed Jan. 13, 2016, both of which are entitled “Saw Chain Link with One or More Oversized Rivet Holes,” and both of which are incorporated herein by reference in their entirety for all purposes except for those sections, if any, that are inconsistent with this specification. 
    
    
     TECHNICAL FIELD 
     Embodiments herein relate to the field of saw chain, and, more specifically, to a saw chain link with one or more oversized rivet holes. 
     BACKGROUND 
     Saw chains for chainsaws typically include a plurality of links, such as cutter links, drive links, and tie straps, coupled to one another by rivets. The rivets are disposed in rivet holes of one or more of the links. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments will be readily understood by the following detailed description in conjunction with the accompanying drawings and the appended claims. Embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings. 
         FIG. 1A  illustrates a front view of a saw chain on a guide bar, the saw chain including a cutter drive link with an oversized rivet hole, and the cutter drive link positioned in a first orientation, in accordance with various embodiments; 
         FIG. 1B  illustrates a front view of the saw chain of  FIG. 1A , with the cutter drive link in a second orientation, in accordance with various embodiments; 
         FIG. 2A  illustrates a front view of a saw chain on a guide bar, with a cutter drive link of the saw chain including an oversized rivet hole and positioned in a first orientation, in accordance with various embodiments; 
         FIG. 2B  illustrates a front view of the saw chain of  FIG. 2A , with the cutter drive link in a second orientation, in accordance with various embodiments; 
         FIG. 3  illustrates a front view of a saw chain including a cutter drive link with an oversized rivet hole that has a cross-sectional shape corresponding to a slot, in accordance with various embodiments; 
         FIG. 4A  illustrates a front view of a saw chain including a cutter drive link with an oversized rivet hole that has a cross-sectional shape corresponding to a curved slot and showing the cutter drive link in a first orientation, in accordance with various embodiments; 
         FIG. 4B  illustrates a front view of the saw chain of  FIG. 4A  with the cutter drive link in a second orientation, in accordance with various embodiments; 
         FIG. 5A  illustrates a front view of a saw chain including a cutter drive link with an oversized rivet hole that has a cross-sectional shape corresponding to an arc-shaped slot and showing the cutter drive link in a first orientation, in accordance with various embodiments; 
         FIG. 5B  illustrates a front view of the saw chain of  FIG. 5A  with the cutter drive link in a second orientation, in accordance with various embodiments; 
         FIG. 6A  illustrates a front view of a saw chain on a guide bar, the saw chain including cutter drive links with an oversized rivet hole, in accordance with various embodiments; 
         FIG. 6B  illustrates a closer view of a portion of the saw chain of  FIG. 6A ; 
         FIG. 6C  illustrates a closer view of another portion of the saw chain of  FIG. 6A ; 
         FIG. 7  illustrates a front view of another saw chain on a guide bar, the saw chain including cutter drive links with an oversized rivet hole, in accordance with various embodiments; 
         FIG. 8  illustrates a front view of another saw chain on a guide bar, the saw chain including bumper drive links with an oversized rivet hole, in accordance with various embodiments; 
         FIG. 9  illustrates a front view of a tie rivet with an integrated cam rivet in accordance with various embodiments; 
         FIG. 10A  illustrates a front view of a saw chain including cutter drive links and tie rivets that include a cam rivet, in accordance with various embodiments; 
         FIG. 10B  illustrates a rear view of the saw chain of  FIG. 10A ; 
         FIG. 11A  illustrates a bi-directional saw chain traveling in a first direction while under an applied load (e.g., while cutting wood), in accordance with various embodiments; 
         FIG. 11B  illustrates the bi-directional saw chain of  FIG. 11A  traveling in a second direction while not under an applied load (e.g., while not cutting wood), in accordance with various embodiments; 
         FIG. 11C  illustrates a perspective view of the bi-directional saw chain of  FIG. 11A ; 
         FIG. 11D  illustrates a top view of the bi-directional saw chain of  FIG. 11A ; 
         FIG. 12A  illustrates a front view of a bi-directional cutter drive link in accordance with various embodiments; 
         FIG. 12B  illustrates a top view of the bi-directional cutter drive link of  FIG. 12A  in accordance with various embodiments; 
         FIG. 13  illustrates a front view of a bumper drive link with vertically offset oversized rivet holes, in accordance with various embodiments; 
         FIG. 14  illustrates a front view of a bumper drive link with oversized rivet holes, in accordance with various embodiments; 
         FIG. 15A  illustrates a saw chain in which the bumper drive link may move closer to the bar rails when a load is placed on the bumper portion and may move back to the original position when the load is removed, in accordance with various embodiments; 
         FIG. 15B  illustrates a saw chain in which the bumper drive link  1502  may tip or rotate in response to a load placed on the bumper portion and/or orienting forces from a sprocket, in accordance with various embodiments; 
         FIG. 16  illustrates a tie rivet with cam rivets in accordance with various embodiments; 
         FIG. 17  illustrates another tie rivet with cam rivets in accordance with various embodiments; 
         FIG. 18  illustrates another tie rivet with cam rivets in accordance with various embodiments; 
         FIG. 19A  illustrates a front view of a saw chain with a bumper drive link and tie rivets, in accordance with various embodiments; 
         FIG. 19B  illustrates a perspective view of the saw chain of  FIG. 19A ; 
         FIG. 20  illustrates a saw chain as it traverses a guide bar, the saw chain including cutter tie strap links, bumper drive links, and tie rivets, in accordance with various embodiments; 
         FIG. 21  illustrates a bumper drive link with vertically offset rivet holes, in accordance with various embodiments; 
         FIG. 22  illustrates another saw chain as it traverses a guide bar, the saw chain including cutter tie strap links, bumper drive links, and tie rivets, in accordance with various embodiments; 
         FIG. 23A  illustrates a front view of a cutter tie strap link with a pair of cam rivets, in accordance with various embodiments; 
         FIG. 23B  illustrates a perspective view of the cutter tie strap link of  FIG. 23A ; 
         FIG. 24A  illustrates a perspective view of a saw chain in accordance with various embodiments; 
         FIG. 24B  illustrates a front view of the saw chain of  FIG. 24A  under chain tension and no cutting load; 
         FIG. 24C  illustrates a front view of the saw chain of  FIG. 24A  under chain tension and with a cutting load applied; and 
         FIG. 25  illustrates a front view of a saw chain including cutter drive links and shows tension and cutting forces that are applied to the cutter drive links, in accordance with various embodiments. 
     
    
    
     DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTS 
     In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration embodiments that may be practiced. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of embodiments is defined by the appended claims and their equivalents. 
     Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding embodiments; however, the order of description should not be construed to imply that these operations are order dependent. 
     The description may use perspective-based descriptions such as up/down, back/front, and top/bottom. Such descriptions are merely used to facilitate the discussion and are not intended to restrict the application of disclosed embodiments. 
     The terms “coupled” and “connected,” along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other. Rather, in particular embodiments, “connected” may be used to indicate that two or more elements are in direct physical contact with each other. “Coupled” may mean that two or more elements are in direct physical contact. However, “coupled” may also mean that two or more elements are not in direct contact with each other, but yet still cooperate or interact with each other. 
     For the purposes of the description, a phrase in the form “A/B” or in the form “A and/or B” means (A), (B), or (A and B). For the purposes of the description, a phrase in the form “at least one of A, B, and C” means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C). For the purposes of the description, a phrase in the form “(A)B” means (B) or (AB) that is, A is an optional element. 
     The description may use the terms “embodiment” or “embodiments,” which may each refer to one or more of the same or different embodiments. Furthermore, the terms “comprising,” “including,” “having,” and the like, as used with respect to embodiments, are synonymous, and are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). 
     With respect to the use of any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity. 
     Embodiments herein provide an apparatus, system, and method for a saw chain link with one or more oversized rivet holes. Embodiments further provide a saw chain that includes a plurality of links coupled to one another by rivets. The links may include one or more links that include one or more oversized rivet holes with rivets disposed in the respective oversized rivet holes. For example, a link may include a body with two rivet holes (e.g., a first rivet hole and a second rivet hole) through the body. A rivet may be disposed in each rivet hole to couple the link to one or more adjacent and/or opposing links in the saw chain. One or more of the rivet holes may be oversized rivet holes. The term “oversized” means that the rivet hole and corresponding rivet may provide a clearance between the rivet and the edge of the rivet hole, wherein the rivet hole is thus larger than the standard size rivet hole. The clearance may allow for relative movement of the link with respect to the rivet. For example, the clearance in some embodiments may be about 0.010 inches or more, such as about 0.020 inches. For a saw chain with a pitch (e.g., distance between the centers of adjacent rivet holes) of 0.75 inches, the maximum clearance may be about 0.25 inches. Other embodiments may use another suitable clearance. 
     In various embodiments, the clearance between the rivet and the oversized rivet hole may allow the link to switch between different stable positions based on one or more conditions. A “stable position” is a position that the link maintains relative to the rivet and/or neighboring links so long as the one or more conditions are met. The oversized rivet may switch between the different stable positions while under tension in the saw chain, e.g., while the saw chain is connected to itself to form an endless loop on a guide bar. As further discussed below, the one or more conditions may include, for example, whether the link is under load (e.g., from a workpiece, such as wood, that is being cut by the saw chain), and/or whether the link is traversing an elongate portion of the guide bar or an end of the guide bar (e.g., a sprocket or a non-sprocket end). 
     In various embodiments, the saw chain may be configured to be driven on a guide bar of a chain saw or a mechanized tree harvester. The guide bar may extend from a body of the chain saw and may generally include a pair of elongate portions running from a proximal end of the guide bar (closer to the body) to a distal end of the guide bar (further from the body). In some embodiments, the elongate portion may include a pair of rails, with a groove disposed between the rails. The elongate portions may be substantially straight or may be curved. The elongate portions may be coupled together by curved portions at the proximal and distal ends of the guide bar to form an endless loop. The curved portions may have a sharper curvature than the elongate portions. 
     The guide bar may further include a sprocket at the proximal end and/or distal end to drive the saw chain around the ends (e.g., curved portions) of the guide bar. For example, the guide bar may include a drive sprocket at the proximal end of the guide bar and a nose sprocket at the distal end of the guide bar. The sprocket may include a spur with a plurality of pockets to engage respective links of the saw chain. In some embodiments, the sprocket may further include a pair of rims with outer edges that define rails. The spur may be sandwiched between the pair of rims. Other embodiments of the sprocket may not include rims. 
     In various embodiments, as discussed above, the saw chain may include a plurality of links coupled to one another in a chain. For example, the saw chain may include one or more cutter links, drive links, and/or tie straps. The cutter links may include a sharpened cutting edge for cutting a workpiece (e.g., wood). In some embodiments, the cutter links may further include a depth gauge to control a depth of cut of the cutter link. For example, the depth gauge may be disposed in front of the cutting element (e.g., in the direction of travel of the saw chain). 
     In various embodiments, the saw chain may include left side links, right side links, and center links. The left side links may ride on a first rail (e.g., left rail) of the guide bar, and the right side links may ride on a second rail (e.g., right rail) of the guide bar. The center links may ride in the groove of the guide bar between the rails. Additionally, the center links may be disposed in a pocket of the sprocket as the center links traverse the sprocket. 
     In various embodiments, the tie straps may be left side links or right side links, and the drive links may be center links. The drive links may include a tang that extends downward from a body of the drive link to ride in the groove of the guide bar and/or engage a pocket of the sprocket. 
     In some embodiments, the cutter links may be integrated into a tie strap. Such a link may be referred to as a cutter tie strap. The cutter tie strap may be a side link configured to ride on a left or right rail of the guide bar. 
     Additionally, or alternatively, some embodiments may provide a saw chain including cutter links integrated into a drive link. Such a link may be referred to as a cutter drive link. The cutter drive link may include a body with a tang extending downward from the body, and a cutting element and depth gauge extending upward from the body. Some embodiments may provide a saw chain including a plurality of cutter drive links coupled to one another by tie straps. For example, in some embodiments, the saw chain may include only cutter drive links, tie straps, and rivets. 
     In some embodiments, one or more of the drive links may be bumper drive links. The bumper drive links may include a bumper portion that extends upward from the body that is designed to extend radially as the bumper drive link traverses one or more of the sprockets. The radial extension of the bumper portion may prevent or reduce kickback of the saw chain during nose cuts (when the nose end of the chain saw is used to cut a workpiece). 
     In some embodiments, one or more of the tie straps may include one or more integrated rivets that extend from the body of the tie strap. Such a link may be referred to as a tie rivet. In some embodiments, the tie rivet may include two integrated rivets to engage with respective rivet holes in an opposing tie strap. In other embodiments, the tie rivet may include one integrated rivet and one rivet hole, and may engage with an opposing tie strap that also includes one integrated rivet and one rivet hole, such that the two tie straps are complementary. 
     Furthermore, in some embodiments, the saw chain may be a bi-directional saw chain that can be used in two orientations on the guide bar. For example, the saw chain may be used in a first orientation in which the first rivet hole of the drive links is in the forward direction (e.g., ahead of the second rivet hole in the direction of travel of the saw chain), and may also be used in a second orientation in which the second rivet hole of the drive links is in the forward direction (e.g., ahead of the first rivet hole in the direction of travel). The bi-directional saw chain may be used for a while in the first orientation, and then flipped around and used for a while in the second orientation. Thus, the bi-directional saw chain may provide an extended useful life compared with saw chains that are only usable in one direction. 
     In various embodiments, the bi-directional saw chain may include cutter links that have a first cutting element to perform cuts when the saw chain is in the first orientation and a second cutting element to perform cuts when the saw chain is in the second orientation. The second cutting element may not cut the workpiece when the saw chain is in the first orientation, and the first cutting element may not cut the workpiece with the saw chain is in the second orientation. Cutter links with first and second cutting elements as described above may be referred to as bi-directional cutter links. 
     In other embodiments, a bi-directional chain may include different cutter links (e.g., cutter drive links) that are oriented in opposite directions, to perform cuts when the chain travels in opposite directions. That is, one set of cutter links of the bi-directional chain may perform cuts when the bi-directional chain travels in a first direction, and another set of cutter links of the bi-directional chain may perform cuts when the bi-directional chain travels in a second direction opposite the first direction. One or more (e.g., all) of the cutter links may include one or more oversized rivet holes as described herein. 
     As discussed above, one or more of the links of the saw chain may include one or more oversized rivet holes. For example, one or more of the drive links may include one or more oversized rivet holes. The drive links with one or more oversized rivet holes may be, for example, cutter drive links and/or bumper drive links. Alternatively, one or more of the side links, such as one or more cutter tie straps, may include one or more undersized rivet flanges. 
     In some embodiments, the link may include a first rivet hole that is an oversized rivet hole and a second rivet hole that is a normal (standard) rivet hole. The oversized rivet hole may provide a first clearance between the edge of the oversized rivet hole and a first rivet disposed in the oversized rivet hole that is greater than a second clearance between the edge of the normal rivet hole and a second rivet disposed in the normal rivet hole. For example, the second clearance may be about 0.002 inches, and the first clearance may be about 0.010 inches or more, such as about 0.020 inches. 
     In some embodiments, a diameter of the oversized rivet hole may be larger than a diameter of the normal rivet hole. The first and second rivets may have respective flanges that may be disposed in the oversized rivet hole and normal rivet hole, respectively. In some embodiments, the first and second rivets may be the same size (e.g., may have flanges of the same diameter). Alternatively, the flange of the first rivet may have a diameter that is less than a diameter of the flange of the second rivet. The rivets with different diameter flanges may be used with rivet holes of the same diameter (with the rivet hole with the smaller diameter rivet corresponding to the oversized rivet hole) or with rivet holes of different diameters. 
     In some embodiments, a cutter drive link may include an oversized rivet hole below the cutting element, and a normal rivet hole below the depth gauge. The oversized rivet hole may, for example, be disposed behind the normal rivet hole with respect to the direction of travel of the link. The oversized rivet hole may cause the cutter drive link to rotate when a load is applied to the cutter drive link (e.g., by a workpiece that is being cut) so that a difference between a height of the cutter element (relative to the guide bar) and a height of the depth gauge is less when the load is applied than when the load is not applied. 
     For example,  FIGS. 1A and 1B  illustrate a portion of a saw chain  100  disposed on an elongate portion of a guide bar  102 . The saw chain  100  includes a cutter drive link  104 , a tie rivet  106 , and a tie rivet  108 .  FIG. 1A  shows the saw chain  100  when the cutter drive link  104  is not subject to a load, and  FIG. 1B  shows the saw chain  100  when a load is applied to the cutter drive link  104 . 
     The cutter drive link  104  includes a body  110  with an oversized rivet hole  112  and a normal rivet hole  114  disposed through the body  110 . The oversized rivet hole  112  is disposed behind the normal rivet hole  114  with respect to a direction of travel of the saw chain  100 . The cutter drive link  104  further includes a cutting element  116  that extends upward from the body  110  above the oversized rivet hole  112 . Additionally, the cutter drive link  104  includes a depth gauge  118  that extends upward from the body  110  above the normal rivet hole  114 . 
     In various embodiments, the tie rivet  106  includes a body  120 , and a first rivet  122  and a second rivet  124  that extend from the body  120 . For example, the first rivet  122  and second rivet  124  may extend approximately perpendicularly from an inner surface of the body  120 . The first rivet  122  (e.g., a flange of the first rivet  122 ) may be disposed in the oversized rivet hole  112 . A diameter of the first rivet  122  may be less than a diameter of the oversized rivet hole  112 , thereby providing a clearance between the first rivet  122  and the oversized rivet hole  112 . In one non-limiting example, the first rivet  122  may have a diameter of about 0.100 inches, and the oversized rivet hole  112  may have a diameter of about 0.121 inches. Accordingly, the clearance may be about 0.021 inches. In other embodiments, the first rivet  122  and oversized rivet hole  112  may have any suitable clearance, such as a clearance of 0.010 inch or more. 
     In various embodiments, the cutter drive link  104  may be in a first orientation, as shown in  FIG. 1A , when the cutter drive link  104  is in an unengaged state (e.g., when the cutter drive link  104  is not subject to a cutting load). When the cutter drive link  104  is subjected to a cutting load during a cutting operation, the cutter drive link  104  may move to a second orientation, as shown in  FIG. 1B . The cutter drive link  104  may stay in the second orientation during the cutting operation (e.g., when the cutting load is above a threshold). The position of the oversized rivet hole  122  and cutting element  116  may be lower with respect to the rail of the guide bar  102  and/or depth gauge  118  in the second orientation than in the first orientation. 
     For example, the cutter drive link  104  may have a depth gauge setting that corresponds to a difference in height between the cutting element  116  and the depth gauge  118  in a direction perpendicular to the direction of travel of the cutter drive link  104 . The depth gauge setting may be greater in the first orientation than in the second orientation. For example, as shown in  FIG. 1A , the depth gauge setting in the first orientation is about 0.011 inches, while, as shown in  FIG. 1B , the depth gauge setting in the second orientation is about 0.05 inches. 
     The movement of the cutter drive link  104  from the first orientation to the second orientation when the cutting load is applied may provide one or more benefits. For example, the movement of the cutting element  116  when the cutting load is applied may reduce the vibration from cutting, thereby promoting a smooth cutting response. Additionally, or alternatively, as discussed above, the cutter drive link  104  may have a greater depth gauge setting in the first orientation when the cut is started, and a lower depth gauge setting in the second orientation during the cutting process. The greater depth gauge setting at the start of the cut may facilitate the initiation of the cut. Additionally, the lower depth gauge setting in the second orientation that is used during the cut may prevent the depth of cut from becoming too large and thereby overpowering the chain saw. 
     Furthermore, a cutter drive link with two normal rivet holes may not have a way to release the tension of the saw chain during a cut, thereby forcing the saw chain to stay engaged in the cut. The resulting chips formed by the saw chain may have a thickness of almost the full depth gauge setting and/or may be longer than chips formed by saw chains with cutter tie strap links (e.g., the chips may be up to an inch long instead of ¼ inch). By allowing the cutter drive link to rock (e.g., rotate) back during the cut, as is provided by the cutter drive link  104 , the chips may be broken up sooner thereby producing smaller chips. The smaller chips may facilitate a clean cut and prevent or reduce clogging of the saw chain  100 . 
     In some embodiments, the cutter drive link  104  may be held in one orientation on the nose of the guide bar (e.g., by the pocket of the sprocket), when the cutter drive link  104  is in the engaged state and the unengaged state (e.g., when the cutter drive link  104  is subjected to a load and not subjected to a load, respectively). Accordingly, the cutter drive link  104  may maintain stability for nose cuts (e.g., boring cuts). 
       FIGS. 2A and 2B  illustrate a saw chain  200  that is similar to the saw chain  100 , but includes a cutter drive link  204  with a greater depth gauge setting than the cutter drive link  104 . The cutter drive link  204  includes a body  210  with an oversized rivet hole  212  and a normal rivet hole  214  disposed through the body  210 . The oversized rivet hole  212  is disposed behind the normal rivet hole  214  with respect to a direction of travel of the saw chain  200 . The cutter drive link  204  further includes a cutting element  216  that extends upward from the body  210  above the oversized rivet hole  212 . Additionally, the cutter drive link  204  includes a depth gauge  218  that extends upward from the body  210  above the normal rivet hole  214 . 
     The cutter drive link  204  may be in a first orientation, as shown in  FIG. 2A , when in an unengaged state (e.g., when no cutting load is applied). The cutter drive link  204  may be in a second orientation, as shown in  FIG. 2B , when a cutting load is applied. As shown in  FIG. 2A , the depth gauge setting of the cutter drive link  204  in the first orientation may be about 0.015 inches, and the depth gauge setting of the cutter drive link  204  in the second orientation may be about 0.010 inches. The depth gauge setting of the cutter drive link  204  in the first orientation may be greater than the depth gauge setting that would be used for a cutter drive link with two normal rivet holes. The oversized rivet hole  212  of the cutter drive link  204  allows the use of a greater depth gauge setting in the first orientation, since the depth gauge setting will be lower during the cutting operation. The greater depth gauge setting in the first orientation may facilitate initiation of the cut. 
     In some embodiments, the oversized rivet hole of the cutter drive link may have a non-circular cross-sectional shape. For example, the oversized rivet hole may have a cross-sectional shape that corresponds to a slanted oval, a kidney bean shape, a slot with substantially straight side walls and curved end walls, an arc-shaped slot, or another suitable shape. Additionally, in some embodiments, a movement axis of the oversized rivet hole may be disposed at an angle with respect to a direction of travel of the saw chain and/or a bar perpendicular line that is perpendicular to the bar contour below the oversized rivet hole. The movement axis may generally correspond to the path of travel of the rivet hole with respect to the rivet when the cutter drive link moves between the first orientation and the second orientation. The angled movement axis of the oversized rivet hole may cause the rivet to move horizontally between the first and second orientations. Accordingly, the distance between the adjacent links (e.g., tie straps) that are coupled to the cutter drive link by the rivets may change from the first orientation to the second orientation. 
       FIG. 3  illustrates a saw chain  300  in accordance with various embodiments. Saw chain  300  includes a cutter drive link  304  with an oversized rivet hole  312  that has a cross-sectional shape corresponding to a slot, with side walls that are substantially straight and end walls that are curved. In other embodiments, the side walls may also be curved (e.g., less severely than the end walls). A movement axis  331  of the oversized rivet hole  312  may be disposed at an angle  330  with respect to the direction of travel of the saw chain  300  and/or the bar perpendicular line. The movement axis  331  may generally correspond to the path of travel of the oversized rivet hole  312  with respect to the rivet  322 , enabled by the clearance between the oversized rive hole  312  and the rivet  322 . For example, the movement axis  331  may correspond to the long axis of the oversized rivet hole  312 .  FIG. 3  illustrates the saw chain  300  when the cutter drive link  304  is subjected to a cutting force (e.g., while cutting). 
     In various embodiments, the cutter drive link  304  may further include a cutting element  316  and a depth gauge  318 . A rivet  322  of a tie strap  306  may be disposed in the oversized rivet hole  312 . The cutter drive link  304  may move with respect to the rivet  322 , e.g., when a cutting load is applied. For example, in an unengaged state (e.g., when no cutting load is applied), the rivet  322  may be disposed in a lower portion of the oversized rivet hole  312 . In some embodiments, there may be a small gap between the lower boundary of the oversized rivet hole  312  and the rivet  322  during engagement as the cutting load and restoring force are balanced by the cutting element  316  moving downward to decrease the cutting load to match the chain tension induced restoring force. Tension in the chain causes a rivet  322  to come against the rear wall of angled oversized rivet hole  312  which is oriented at the angle  330 . The chain tension acting against the rear wall at angle  330  creates a vertical restoring force. The position of the rivet  322  and the oversized rivet hole  312  shown in  FIG. 3  may be one example of a stable cutting position in which the upper portion of the oversized rivet hole  312  is not driven to contact the rivet by the applied load. 
     When a cutting load is applied to the cutter drive link  304 , the cutting element  316  may move so that the rivet  322  is disposed in an upper portion of the oversized rivet hole  312 . The angled oversized rivet hole  312  may cause the rivet  322  to move in a horizontal direction between the first and second orientations. Accordingly, the distance between the tie strap  306  and an adjacent tie strap (e.g., tie strap  308 ) may be different in the first orientation than in the second orientation. 
     In various embodiments, the value of the angle of the rear wall of the oversized rivet hole  312  (e.g., the angle  330  of the movement axis  331 ) may determine the amount of restorative force that is provided by tension in the saw chain  300 . The restorative force may correspond to the amount of force that pushes the cutter drive link  304  toward the first orientation that the cutter drive link  304  has in the unengaged state (e.g., the force that must be overcome by the cutting load to push the move the cutter drive link  304  to the second orientation). A higher value of the angle  330  (e.g., the more the oversized rivet hole  312  is angled from vertical) may provide more pitch change (e.g., change in the distance between adjacent links) per degree of rotation of the cutter drive link  304 , and also thereby more tension change. 
       FIGS. 4A and 4B  illustrate a saw chain  400  that includes a cutter drive link  404  with an oversized rivet hole  412  that has a cross-sectional shape corresponding to a curved slot. A rivet  422  of a tie rivet  406  is disposed in the oversized rivet hole  412 .  FIG. 4A  shows the cutter drive link  404  in a first orientation (e.g., when no cutting load is applied to the cutter drive link  404 ).  FIG. 4B  shows the cutter drive link  404  in a second orientation (e.g., when a cutting load or possibly a potentially damaging load is applied). In  FIG. 4B  the cutting element of the cutting element of the cutter drive link  404  is so reduced in height that the depth gauge stands higher. This orientation allows the cutter to move out of the way of rocks or metal parts so as to reduce damage to the cutting element. 
     As shown, a distance between a center of a rear rivet  424  of the tie rivet  406  and a center of the rivet (not shown) disposed in the rivet hole  416  of the cutter drive link  404  may be greater in the first orientation than in the second orientation. In one non-limiting example, as shown in  FIGS. 4A and 4B , the distance may be about 0.508 inches in the first orientation and about 0.492 in the second orientation. The pitch change from the decreased distance in the second orientation may increase the restorative force to push the cutter drive link  404  to the first orientation when the cutting load is removed. 
     Alternatively, in some embodiments, the oversized rivet hole may have a cross-sectional shape that corresponds to an arc-shaped slot so that there is no pitch change between the first orientation and the second orientation. For example,  FIGS. 5A and 5B  illustrate a saw chain  500  that includes a cutter drive link  504  with an oversized rivet hole  512  that has a cross-sectional shape corresponding to an arc-shaped slot that is concentric with the rivet hole  516  of the cutter drive link  504 . A rivet  522  of a tie rivet  506  is disposed in the oversized rivet hole  512 .  FIG. 5A  shows the cutter drive link  504  in a first orientation (e.g., when no cutting load is applied to the cutter drive link  504 ).  FIG. 5B  shows the cutter drive link  504  in a second orientation (e.g., when a cutting load or possibly a potentially damaging load is applied). 
     As shown, a distance between a center of a rear rivet  524  of the tie rivet  506  and a center of the rivet (not shown) disposed in the rivet hole  516  of the drive link  504  may be the same in the first orientation and in the second orientation. Accordingly, the cutter drive link  504  may change between the first orientation and the second orientation without changing the pitch and/or tension of the saw chain  500 . 
     In other embodiments, the front rivet hole of the drive link may be the oversized rivet hole. For a cutter drive link with an oversized rivet hole as the front rivet hole, the depth gauge may move lower (e.g. away from the workpiece being cut) when a cutting load is applied to the cutter drive link. Such a cutter drive link may be used to prevent/reduce kickback (e.g., as the cutter drive link traverses the nose of a non-sprocket nose bar (a guide bar that does not include a sprocket on the nose)). Lowering the depth gauge of the cutter drive link may increase the heel interference of the cutter drive link, decrease the cutting edge relief angle (e.g., the angle of the top surface of the cutting element), and/or decrease the cutting edge engagement with the workpiece (e.g., wood). The heel of the cutter drive link may refer to the top rear portion of the cutting element. Heel interference may result from an orientation of the cutter drive link on the nose of the guide bar in which the heel of the cutting element extends further from the rail of the guide bar than the cutting edge. The wood may contact the heel first and the heel may prevent the cutting edge from cutting the wood. 
     For example,  FIG. 6A  illustrates a saw chain  600  that includes cutter drive links  604   a - f  with an oversized rivet hole  612  as the front rivet hole, in accordance with various embodiments. The saw chain  600  includes a plurality of cutter drive links  604   a - f , shown in  FIG. 6A  as they approach or traverse a nose of a guide bar  602 . In some embodiments, the guide bar  602  may not include a nose sprocket on the nose of the guide bar. In other embodiments, the guide bar  602  may include a nose sprocket. In various embodiments, the cutter drive links  604   b  and  604   e  are shown while under a cutting load, and cutter drive links  604   a  and  604   f  are shown while not under a cutting load. 
     The cutter drive links  604   a - f  each include an oversized rivet hole  612 , a normal rivet hole  614 , a cutting element  616 , and a depth gauge  618 . The oversized rivet hole  612  is disposed below the depth gauge  618 , and the normal rivet hole  614  is disposed below the cutting element  616 . The saw chain  600  further includes a plurality of tie rivets  606  with integrated rivets that extend through the respective oversized rivet holes  612  and normal rivet holes  614  of the cutter drive links  604   a - f . The opposing tie straps are not shown to allow the oversized rivet holes  612  and normal rivet holes  614  to be viewed. 
     In various embodiments, with the oversized rivet hole  612  disposed below the depth gauge  618 , the depth gauge  618  may lower with respect to the cutting element  616  when the cutter drive link  604   a - f  when subjected to a load (e.g., from cutting engagement). The lowering of the depth gauge  618 , when the chain is on the nose of the bar, may increase the heel interference of the cutter drive link  604   a - f , decrease the cutting edge relief angle, and decrease the amount of engagement between the cutting edge and the workpiece (e.g., wood). This arrangement may be used to prevent or reduce kickback of the saw chain  600  as it traverses the nose of the guide bar  600 . 
       FIG. 6B  illustrates a close-up view of cutter drive links  604   a  and  604   b  that traverse the elongate portion of the guide bar  602 . As shown, cutter drive link  604   b , which is under a cutting load may be rotated with respect to cutter drive link  604   a  so that the depth gauge setting of cutter drive link  604   b  is greater than the depth gauge setting of cutter drive link  604   a  (e.g., 0.030 inches compared with 0.015 inches). Accordingly, the cutting load on the cutter drive link  604   b  may increase the depth of cut of the cutter drive link  604   b.    
       FIG. 6C  illustrates a close-up view of cutter drive links  604   e  and  604   f  to illustrate the potential movement of the depth gauge while the cutter drive links  604   e  and  604   f  traverse the nose of a guide bar  602  that does not include a nose sprocket. As discussed above, cutter drive link  604   e  is shown under a cutting load and cutter drive link  604   f  is shown not under a cutting load. 
       FIG. 6C  also shows radial extension distances  634   a ,  634   b ,  634   c ,  634   d ,  634   e , and  634   f . The radial extension distance  634   a  is a distance from a center of rotation  636  of the chain around the bar nose to a rear portion (heel) of the cutting element  616  of the cutter drive link  604   e , radial extension distance  634   b  is a distance from the center of rotation  636  to a front portion of the cutting element  616  of the cutter drive link  604   e , and radial extension distance  634   c  is a distance from the center of rotation  636  to the depth gauge  618  of the cutter drive link  604   e  (e.g., to the most extended portion of the depth gauge  618  of cutter drive link  604   e ). Similarly, the radial extension distance  634   d  is a distance from the center of rotation  636  of the chain around the bar nose to a rear portion (heel) of the cutting element  616  of the cutter drive link  604   f , radial extension distance  634   e  is a distance from the center of rotation  636  to a front portion of the cutting element  616  of the cutter drive link  604   f , and radial extension distance  634   f  is a distance from the center of rotation  636  to the depth gauge  618  of the cutter drive link  604   f  (e.g., to the most extended portion of the depth gauge  618  of cutter drive link  604   f ). 
     As shown, for cutter drive link  604   e , the radial extension distance  634   a  is greater than the radial extension distance  634   b , and the radial extension distance  634   b  is greater than the radial extension distance  634   c . In contrast, for cutter drive link  604   f , the radial extension distance  634   d  is less than the radial extension distances  634   e  and  634   f , and the radial extension distance  634   e  is greater than the radial extension distance  634   f . Accordingly, the cutting load on the cutter drive link  604   e  results in increased heel interference for the cutter drive link  604   e  compared with the cutter drive link  604   f  (which is not under a cutting load). The heel of the cutter drive link  604   e  acts as a bumper so that the cutting edge of the cutting element  616  and the depth gauge  618  of the cutter drive link  604   e  do not contact the wood. 
     As discussed above, the change in the depth gauge setting and/or radial extension distances as the cutter drive links  604   a - f  may prevent or reduce kickback of the saw chain  600 . Additionally, or alternatively, a similar arrangement may be used to orient the cutter drive links  604   a - f  on a sprocket (e.g., on the drive sprocket or nose sprocket) to facilitate sharpening of the cutter drive links  604   a - f.    
       FIG. 7  illustrates a saw chain  700  that is traversing the end of a guide bar  702  that includes a sprocket  738 . The sprocket  738  may be a drive sprocket or a nose sprocket. The saw chain  700  may include a plurality of cutter drive links  704   a - f . The cutter drive links  704   a  and  704   b  are shown traversing the elongate portion of the guide bar approaching the sprocket  738 , while cutter drive links  704   c - f  are disposed in respective pockets  740  of the sprocket  738 . The cutter drive links  704   a - f  each include an oversized rivet hole  712 , a normal rivet hole  714 , a cutting element  716 , and a depth gauge  718 . The oversized rivet hole  712  is disposed below the depth gauge  718 , and the normal rivet hole  714  is disposed below the cutting element  716 . 
     As shown, cutter drive link  704   a , which is traversing the elongate portion of the guide bar  702 , has a depth gauge setting that is greater than the depth gauge setting of the cutter drive link  704   e , which is traversing the sprocket  738 . The cutter drive links may change their depth gauge setting in response to cutting forces while the drive links traverse the elongate portion of the guide bar  702  (e.g., cutter drive links  702   a  and  702   b  as shown in  FIG. 7 ). However, the sprocket  738  may orient the cutter drive links in a desired orientation and hold the cutter drive links in that orientation as they traverse the sprocket  738  (e.g., on the nose of the guide bar). The cutter drive links may not change their depth gauge setting in response to cutting forces while the cutter drive links traverse the sprocket  738 . 
       FIG. 8  illustrates a saw chain  800  that is traversing the end of a guide bar  802  that includes a sprocket  838 . The sprocket  838  may be a drive sprocket or a nose sprocket. The saw chain  800  includes a plurality of cutter drive links  804   a - d , and a plurality of bumper drive links  842   a - b.    
     The cutter drive links  804   a - d  each include two normal rivet holes  812  and  814 , a cutting element  816 , and a depth gauge  818 . The bumper drive links  842   a - b  each include an oversized rivet hole  844  and a normal rivet hole  845 . The bumper drive links  842   a - b  further include a bumper portion  846  that extends upward above the oversized rivet hole  844 . 
     On the elongate portion of the guide bar, as illustrated by cutter drive link  804   a  and bumper drive link  842   a , the bumper portion  846  of the bumper drive link  842   a  is disposed at a lower height (e.g., relative to the guide bar  802 ) than the depth gauge  818  and the cutting element  816  of the cutter drive link  804   a . The lower height of the bumper portion  846  on the elongate portion of the guide bar may prevent the bumper portion  846  from interfering with cuts made using the elongate portion of the guide bar. 
     When the links traverse the sprocket  838  of the guide bar  802 , as illustrated by cutter drive link  804   c  and bumper drive link  842   b , the bumper portion  846  is disposed at a greater height than the depth gauge  818  and the cutting element  816  of the cutter drive link  804   c . Additionally, the depth gauge setting of the cutter drive link  804   c  is reduced compared with the depth gauge setting of the cutter drive link  804   a . The greater height of the bumper portion  846  on the sprocket  838  may prevent or reduce kickback of the saw chain  800  on the nose sprocket  838 . 
     In other embodiments, the saw chain may include a bumper drive link that includes a bumper portion disposed above the forward rivet hole and that is disposed immediately behind a cutting element of an adjacent link in the saw chain. The bumper drive link may include an oversized rivet hole below the bumper portion. 
     In some embodiments, the saw chain may include a tie rivet that includes one or more cam rivets. The cam rivet may include a hub that is off-center from a flange of the cam rivet. The flange may be disposed in the rivet hole of the cutter drive link, while the hub may be disposed in the opposing tie strap. Accordingly, the cam rivet may allow vertical displacement of the cutter drive link with respect to the connecting tie straps. 
     For example,  FIG. 9  illustrates a front view of a tie rivet  950  with a cam rivet  952  and a coaxial rivet  954 . The coaxial rivet  954  includes a flange  956  and a hub  958  that have a same central axis. In contrast, the cam rivet  952  includes a flange  960  that has a different central axis from a hub  962  of the cam rivet  952 . In some embodiments, the flange  960  may have a cross-sectional shape that is substantially circular. In other embodiments, the flange  960  may have a non-circular cross-sectional shape (e.g., oval, ellipse, etc.). In some embodiments, the flange  960  of the cam rivet  952  may be vertically offset from the flange  956  of the coaxial rivet  954  (e.g., with respect to a longitudinal axis of the tie rivet  950 ). 
       FIG. 10A  illustrates a front view of a saw chain  1000  on a guide bar  1002  in accordance with various embodiments. The saw chain  1000  includes a cutter drive link  1004   a  and a cutter drive link  1004   b  that are coupled to one another by a tie rivet  1050   a  that includes a cam rivet  1052   a  and a coaxial rivet  1054   a . The tie rivet  1050   a  may be similar to the tie rivet  950  of  FIG. 9 . The cutter drive link  1004   a  includes a cutting element  1016   a  disposed above a rear rivet hole  1012   a , and a depth gauge  1018   a  disposed above a front rivet hole  1014   a . Similarly, the cutter drive link  1004   b  includes a cutting element  1016   b  disposed above a rear rivet hole  1012   b , and a depth gauge  1018   b  disposed above a front rivet hole  1014   b.    
     The cam rivet  1052   a  of the tie rivet  1050   a  is disposed in the rear rivet hole  1012   b  of the cutter drive link  1004   b , which is below the cutting element  1016   b . The coaxial rivet  1054   a  is disposed in the front rivet hole  1014   a  of the cutter drive link  1004   a , which is below the depth gauge  1018   a . A cam rivet  1052   b  of another tie rivet  1050   b  is disposed in the rear rivet hole  1012   a  of the cutter drive link  1004   a , and a coaxial rivet  1054   b  of another tie rivet  1050   c  is disposed in the front rivet hole  1014   b  of the cutter drive link  1004   b.    
     In various embodiments, the cam rivet  1052   b  may cause the depth gauge setting of the cutter drive link  1004   a  to change as the cutter drive link  1004   a  rotates with respect to the tie rivets  1050   a - b , for example, when the cutter drive link  1004   a  goes from the elongate portion of the guide bar to the end of the guide bar. The depth gauge setting may be changed in a similar relationship to that discussed herein with respect to the cutter drive links with oversized rivet holes. 
       FIG. 10B  illustrates a rear view of the saw chain  1000 , showing that the tie rivets  1050   a - c  are angled with respect to the guide bar  1002 . This is caused by the vertical offset of the flanges of the cam rivets  1052  compared with the flanges of the coaxial rivets  1054 . 
     As discussed above, the oversized rivet holes may also be used in a saw chain with bi-directional cutter drive links that are designed to be used in two different orientations on the guide bar. For example, the saw chain may be used in a first orientation in which the first rivet hole of the drive links is in the forward direction (e.g., ahead of the second rivet hole in the direction of travel of the saw chain), and may also be used in a second orientation in which the second rivet hole of the drive links is in the forward direction (e.g., ahead of the first rivet hole in the direction of travel). 
       FIGS. 11A and 11B  illustrate front views of a bi-directional saw chain  1100  in accordance with various embodiments. Additionally,  FIG. 11C  illustrates a perspective view of the bi-directional saw chain  1100 , and  FIG. 11D  illustrates a top view of the bi-directional saw chain  1100 . The saw chain  1100  includes a plurality of bi-directional cutter drive links  1104  coupled to one another by tie rivets  1106 . 
     The bi-directional cutter drive links  1104  include two oversized rivet holes  1112  and  1114 . The bi-directional cutter drive links  1104  further include a first cutting element  1116  and a second cutting element  1117  that extend up from the middle of the bi-directional cutter drive link  1104  and are oriented in opposite directions. The first cutting element  1116  may be used to cut when the bi-directional cutter drive link  1104  travels in a first direction with the rivet hole  1114  as the forward rivet hole, and the second cutting element  1117  may be used to cut when the bi-directional cutter drive link  1104  travels in a second direction with the rivet hole  1112  as the forward rivet hole (e.g., opposite the first direction). The bi-directional cutter drive link  1104  may further include a depth gauge  1118  and a depth gauge  1119  extending above the body of the bi-directional cutter drive link  1104  at opposing ends of the bi-directional cutter drive link  1104  (e.g., on opposite sides of the cutting elements  1116  and  1117 ). 
     The tie rivets  1106  of saw chain  1100  include a first rivet  1122  that is disposed in the rivet hole  1112  of one bi-directional cutter drive link  1104 , and a second rivet  1124  that is disposed in the rivet hole  1114  of an adjacent bi-directional cutter drive link  1104 . A diameter of the first rivet  1122  may be less than a diameter of the oversized rivet hole  1112 , thereby providing a clearance between the first rivet  1122  and the oversized rivet hole  1112 . Additionally, a diameter of the second rivet  1124  may be less than a diameter of the oversized rivet hole  1114 , thereby providing a clearance between the first rivet  1124  and the oversized rivet hole  1114 . In some embodiments, the clearance may be about 0.010 inches or more, such as about 0.020 inches. 
       FIGS. 11A and 11B  show the cutter drive links  1104  of saw chain  1100  in two different stable positions relative to the rivets  1122  and  1124  and/or guide bar  1102 . For example, a first stable position of the cutter drive links  1104  shown in  FIG. 11A  may occur when the cutter drive links  1104  are traveling in a first direction  1160  in which the rivet  1124  is the forward rivet and the cutting element  1116  is engaged in cutting (and subjected to a cutting force), and a second stable position of the cutter drive links  1104  shown in  FIG. 11B  may occur when the cutting element  1116  is not engaged in cutting and the cutter drive links  1104  are traveling in a second direction  1162  in which the rivet  1122  is the forward rivet. In the first stable position, the cutting element  1116  may extend higher because the oversized rivet holes  1112  and  1114  allow the cutter drive link  1104  to tip up from the cutting force on cutting element  1116 . Cutting element  116  extends higher than the cutting element  1117  to promote cutting by the cutting element  1116  and provide a relief angle for the cutting element  1116 . When the chain travels in the second direction  1162 , the cutting element  1117  may engage in cutting and extend higher than the cutting element  1116  to promote cutting by the cutting element  1117  and provide a relief angle for the cutting element  1117 .  FIG. 11B  shows the cutting elements  1116  and  1117  at the same height above the bar rails because neither is cutting and the restoring forces of the chain tension orient the cutting elements  1116  and  1117  to the same height. 
     In various embodiments, the cutter drive links  1104  of the saw chain  1100  may enter the first or second stable position responsive to respective tensile and cutting forces caused by the saw chain  1100  moving in the first direction  1160  or second direction  1162 . Additionally, or alternatively, the oversized rivet holes  1112  and  1114  of the cutter drive links  1104  may allow the position of the cutter drive links  1104  to change responsive to receiving a cutting load, as described herein. Furthermore, other components of the chain may be used to introduce one or more restorative forces to use the freedom of movement provided by the oversized rivet holes  1112  and  1114  to place the cutter drive links  1104  in a desired position. 
     As best seen in  FIGS. 11C and 11D , the cutting elements  1116  and  1117  of the cutter drive links  1104  may twist out of the plane of the link and extend over a side of the cutter drive link  1104 . In some embodiments, the cutting elements  1116  and  1117  of individual cutter drive links  1104  may extend over a same side of the cutter drive link  1104 . The saw chain  1100  may alternate between cutter drive links  1104  with cutting elements  1116  and  1117  that extend over a one side and cutter drive links  1104  with cutting elements  1116  and  1117  that extend over the opposite side. 
       FIGS. 12A and 12B  illustrate a front view and a top view, respectively, of an alternative cutter drive link  1204  in accordance with various embodiments. The cutter drive link  1204  includes oversized rivet holes  1212  and  1214 , cutting elements  1216  and  1217 , and depth gauges  1218  and  1219 . As best seen in  FIG. 12B , the cutting elements  1216  and  1217  extend over opposite sides of the cutter drive link  1204 . 
     In some embodiments, all cutter links of a saw chain may be cutter drive links  1204 . Alternatively, a saw chain may include a mix of cutter drive links  1204  and cutter drive links  1104 . 
     In some embodiments, a saw chain link may include a pair of oversized rivet holes that are vertically offset from one another (e.g., with respect to a pitch line of the saw chain). For example,  FIG. 13  illustrates a bumper drive link  1300  that includes oversized rivet holes  1302  and  1304 . A bumper portion  1306  of the bumper drive link  1300  is disposed above the oversized rivet hole  1302 . The oversized rivet holes  1302  and  1304  are vertically offset from one another with respect to a pitch line  1308 . As shown, oversized rivet hole  1304  is disposed above oversized rivet hole  1302  with respect to the pitch line  1308 . The offset can be used to control the orientation of the bumper drive link  1300  when subjected to different conditions (e.g., direction of travel, loading, or position on the guide bar (e.g., on the elongate portion or the end)). 
     In some embodiments, the oversized rivet holes may be non-circular. For example,  FIG. 14  illustrates a bumper drive link  1400  with oversized rivet holes  1402  and  1404 , and a bumper portion  1406 . The oversized rivet holes  1402  and  1404  have a cross-sectional shape that corresponds to a curved slot. 
     In various embodiments, the shape of the rivet hole and corresponding rivet may at least partially determine the type and magnitude of the restorative force caused by tension in the saw chain. In some embodiments, different stable positions of a saw chain link may be designed to have substantially the same or similar tensile forces in each position. Accordingly, the saw chain link may rotate to a stable position and stay in that position without a restorative force trying to move it back to another stable position. This may be useful, for example, to allow the position to be stable without a cutting load applied. 
     Alternatively, the saw chain link and/or rivets may be designed to apply a restorative force on the link when the components are in a specific position. The restorative force may encourage the link to move back to another position (e.g., when a cutting load is removed). 
     For example,  FIG. 15A  illustrates a saw chain  1500  in which the bumper drive link  1502  may move closer to the bar rails when a load is placed on the bumper portion and may move back to the original position when the load is removed.  FIG. 15B  illustrates a saw chain  1510  in which the bumper drive link  1502  can tip or rotate in response to a load placed on the bumper portion  1514  and/or orienting forces from a sprocket. 
     In some embodiments, cam rivets may be used with saw chain links that have a pair of oversized rivet holes. For example, one or both of the rivets disposed in the oversized rivet holes of a saw chain link may be a cam rivet.  FIGS. 16, 17, and 18  show example tie rivets  1600 ,  1700 , and  1800 , respectively, with cam rivets in accordance with various embodiments. Although not shown in  FIGS. 16, 17, and 18 , in some embodiments, the tie rivets  1600 ,  1700 , and  1800  may be cutter tie strap links that include a cutting element and/or depth gauge, and integrated cam rivets. 
       FIGS. 19A and 19B  illustrate a saw chain  1900  with a bumper drive link  1902  and tie rivets  1904 . The tie rivets  1904  each have a pair of cam rivets  1906 . 
       FIG. 20  illustrates a saw chain  2000  as it traverses a guide bar  2002 . The saw chain  2000  includes cutter tie strap links  2004   a - c , bumper drive links  2006   a - c , drive links  2008   a - b , and tie rivets  2010   a - b . The cutter tie strap links  2004   a - c  include integrated rivets  2012  and  2014 . In some embodiments, rivet  2014  may be a cam rivet, while rivet  2012  may be a normal co-axial rivet. The tie rivets  2010   a - b  may also include a pair of integrated rivets  2016  and  2018 . The bumper drive links  2006   a - c  may include a rear rivet hole  2020  and a forward rivet hole  2022 . The cam rivet  2014  of the adjacent cutter tie strap link  2004   a - c  may be disposed in the rear rivet hole  2020 , and may provide a clearance between the flange of the cam rivet  2014  and the side of the rear rivet hole  2020 . The rivet  2016  of the adjacent tie rivet  2010   a - b  may be disposed in the forward rivet hole  2022  of the bumper drive link  2006   a - c . The rivet  2016  may not have a significant clearance from the forward rivet hole  2022 . 
     The cutter tie strap links  2004   a - c  further include a cutting edge  2024   a - c  and a depth gauge  2026   a - c . The bumper drive links  2006   a - c  further include a bumper portion  2028   a - c.    
     Bumper drive link  2006   a  is shown in  FIG. 20  with a cutting load applied. Accordingly, the bumper portion  2028   a  is disposed below the depth gauge  2026   a  of the cutter tie strap link  2004   a , thus exposing the depth gauge  2026   a  to the workpiece being cut. Bumper drive link  2006   b  is shown in an interim position as it is starting to engage a nose sprocket of the guide bar  2002 . Bumper drive link  2006   c  is shown when it is engaged with a tooth of the nose sprocket. The bumper portion  2028   c  of the bumper drive link  2006   c  is disposed closer to the cutting edge  2024   c  of the cutter tie strap link  2004   c  than the depth gauge  2026   c , allowing a greater reduction of kickback than afforded by just the depth gauge  2026   c.    
     In some embodiments, the bumper drive links  2006   a - c  of saw chain  2000  may be replaced with bumper drive links with rivet holes that are vertically offset. For example,  FIG. 21  illustrates a bumper drive link  2100  with rivet holes  2102  and  2104  that are vertically offset from one another, and  FIG. 22  illustrates a saw chain  2200  that is similar to the saw chain  2000 , except with the bumper drive links  2100  in place of the bumper drive links  2006   a - c.    
       FIGS. 23A and 23B  illustrate a cutter tie strap link  2300  with a pair of cam rivets  2302  and  2304 , in accordance with various embodiments. The cam rivets  2302  and  2304  extend from a body  2306  of the cutter tie strap link  2300 . The cutter tie strap link  2300  further includes a cutting element  2308  disposed above the cam rivet  2302 , and a depth gauge  2310  disposed above the cam rivet  2304 . 
     In some embodiments, a saw chain may include one or more drive links that include one or more oversized rivet holes, and one or more drive links that do not include oversized rivet holes. The drive links that include one or more oversized rivet holes may change position responsive to a cutting load, while the drive links that do not include oversized rivet holes may not change position responsive to the cutting load. 
     For example,  FIGS. 24A-C  illustrate a saw chain  2400  in accordance with various embodiments. The saw chain  2400  includes a cutter tie strap link  2402 , a bumper drive link  2404 , a bumper drive link  2406 , and a tie rivet  2408 . The bumper drive link  2404  includes an oversized rivet hole  2410  and a normal rivet hole  2412 , with the oversized rivet hole  2410  disposed below a bumper portion  2414  of the bumper drive link  2404 . The bumper drive link  2406  includes two normal rivet holes  2416  and  2418 . 
     The cutter tie strap link  2402  includes integrated rivets  2420  and  2422 . Rivet  2422  is disposed in the oversized rivet hole  2410  of the bumper drive link  2404  and provides a clearance between the oversized rivet hole  2410  of the bumper drive link  2404 . In some embodiments, the rivet  2422  may be a cam rivet as shown in  FIGS. 24A-C . The tie rivet  2408  includes integrated rivets  2424  and  2426  that are disposed in the rivet hole  2412  of the bumper drive link  2404  and the rivet hole  2416  of the bumper drive link  2406 . The cutter tie strap link  2402  further includes a cutting element  2428  disposed above the integrated rivet  2420  and a depth gauge  2430  disposed above the integrated rivet  2422 . Additionally, the bumper drive link  2406  includes a bumper portion  2432 . 
       FIG. 24B  illustrates the saw chain  2400  under chain tension and no cutting load. As shown, the bumper portion  2414  of the bumper drive link  2404  is disposed above the depth gauge  2430  of the cutter tie strap link  2402 . 
       FIG. 24C  illustrates the saw chain  2400  under chain tension and with a cutting load applied. As shown, the bumper portion  2414  of the bumper drive link  2404  is disposed below the depth gauge  2430  to expose the depth gauge  2430  to the cut. The bumper portion  2432  of the bumper drive link  2406  is disposed at the same height with and without the cutting load applied. 
     In various embodiments, the saw chain features (e.g., tension-controlled cutting force compensation features) described herein may be used to provide the overall saw chain with power requirements that better fit the power output of the chain saw. For example, the saw chain features described herein may allow a single chain design to be used on a broader power range of chain saws. Additionally, or alternatively, the saw chain features described herein may lessen the required expertise of the chain saw user to apply the exact feed load needed to maximize the cutting speed without stalling the chain saw. 
       FIG. 25  shows a series of cutter drive links that may be coupled to one another in sequence (e.g., by tie straps (not shown)).  FIG. 25  illustrates how the forces acting on a following cutter drive link will affect a leading cutter drive link due to the increased chain tension created by the following cutter drive link and a chain-tension-compensating feature acting on the leading cutter drive link. Although illustrated with respect to cutter drive links,  FIG. 25  may broadly represent how the forces acting on a following component will affect a leading component due to the increased chain tension created by the following component and a chain-tension-compensating feature on the leading component. 
     In various embodiments, initial tension in the chain is applied by the chain saw user, after the chain is placed on the guide bar and drive sprocket, by an adjusting screw on the chainsaw that moves the guide bar away from the drive sprocket. Additional chain tension may be added between the drive sprocket and chain components in contact with the wood while the chain saw is operating. 
       FIG. 25  shows a saw chain  2500  with cutter drive links  2502   a - e  that include a respective cutting element  2504   a - e , depth gauge  2506   a - e , oversized rivet hole  2508   a - e  and normal rivet hole  2810   a - e . The oversized rivet hole  2508   a - e  may be an angled slot, as shown.  FIG. 25  further illustrates tensions T, T 2 , T 3 , and T 4  that act between adjacent cutter drive links  2502   a - e  as shown. Cutter drive links  2502   a  and  2502   e  are shown in  FIG. 25  while they are not engaged in cutting and cutter drive links  2502   b - d  are shown in  FIG. 25  while they are engaged in cutting (e.g., cutting wood).  FIG. 25  further illustrates the cutting forces CF 1 , CF 2 , and CF 3  that are applied to the cutter drive links  2502   b - d , respectively. 
     In various embodiments, cutter drive link  2502   a  has its cutting element  2504   a  at full height (e.g., relative to the depth gauge  2506   a  and/or the guide bar  2512 ) because of the lifting action of the chain tension and no downward force acting on the cutter drive link  2502   a . The cutting element  2504   b  of cutter drive link  2502   b  has moved to the lowest point (e.g., least cutting position) since the chain tension (T) is low acting on the angled slot of the oversized rivet hole  2508   b  and there is a downward force from the wood being cut. The cutting element  2504   c  of the cutter drive link  2502   c  is raised higher than the cutting element  2504   b  of the cutter drive link  2502   b  due to the increased chain tension (T 2 ) caused by the cutting force (CF 1 ) on the cutter drive link  2502   b  and shortened chain length from the cutting element  2504   b  being at its lowest point. Additionally, the cutting element  2504   d  of cutter drive link  2502   d  is higher than the cutting elements  2504   b  and  2504   c  because of the added cutting forces and shortened chain lengths associated with the cutter drive links  2502   b  and  2502   c  that act on the angled slot of the oversized rivet hole  2508   d  of the cutter drive link  2502   d  and lift the cutting element  2504   d  higher against the downward force of the contacting wood. 
     In general, a cutter drive link with a cutting element that is at a greater height will cut more wood and also have an increased associated cutting force than a cutter drive link with a cutting element that is at a lower height. 
     The tension in the saw chain associated with cutting wood may continue to increase between the components in contact with the wood and the drive sprocket until the operating chain saw motor cannot generate additional pulling force to support a higher load associated with cutting more wood. At this point, the forces required by the saw chain to cut wood are balanced by the motor. The height of the cutter elements will vary so that the cutting forces meet the pull of the chain saw motor. Unlike conventional cutters that cannot change their cutting forces, some of the cutter drive links with tension-controlled cutting-force-compensating features (e.g., the oversized rivet holes  2508   a - d  of the cutter drive links  2502   a - d ) will have their cutting elements lower than others, thereby reducing their required cutting forces so as to compensate for the available power from the chain saw. 
     Although certain embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent embodiments or implementations calculated to achieve the same purposes may be substituted for the embodiments shown and described without departing from the scope. Those with skill in the art will readily appreciate that embodiments may be implemented in a very wide variety of ways. This application is intended to cover any adaptations or variations of the embodiments discussed herein. Therefore, it is manifestly intended that embodiments be limited only by the claims and the equivalents thereof.