CHAIN BAR APPARTUS AND METHODS

Abstract

Chain bar apparatus and methods are disclosed that may be formed from plastic, metal or other materials. Laser cutting of a chain bar core can provide improved structural characteristics, for example when adhesive is used to assemble the chain bar. Flow diversion elements can be used to optimize flow throughout the chain bar.

Claims

1. A laminated element having a peripheral edge surface for supporting a tool component, the laminated element comprising a core element and an outer surface element at least partly coextensive with the core element, wherein the core element includes a perimeter extending around the core element and a closed-circuit wall defining at least one passageway in the core element.

2. The laminated element of claim 1 where in the closed-circuit wall is noncircular and extends from a first end to a second end and where in the passageway between the first and second ends is nonlinear.

3. The laminated element of any of the preceding claims wherein the passageway includes opposing wall space apart from each other substantially a constant distance.

4. The laminated element of any of the preceding claims wherein the passageway does not intersect the perimeter of the core element.

5. The laminated element of any of the preceding claims wherein the passageway is asymmetric.

6. The laminated element of any of the preceding claims wherein the passageway is serpentine.

7. The laminated element of any of the preceding claims wherein the passageway extends completely through the core element.

8. The laminated element of any of the preceding claims further including a plurality of walls defining a respective plurality of passageways in the core element.

9. The laminated element of any of the preceding claims further including a plurality of core elements and wherein at least two of the core elements include respective closed-circuit walls defining passageways in the core element.

10. The laminated element of any of the preceding claims further including adhesive extending into the at least one passageway.

11. The laminated element of claim 10 wherein the passageway extends completely through the core element and the adhesive extends completely through the core element.

12. The laminated element of any of the preceding claims wherein the closed-circuit wall is formed by laser cutting.

13. The laminated element of any of the preceding claims wherein the core element is a plastic core element.

14. The laminated element of claim 13 wherein the plastic core element includes a relatively flat surface where in the flat surface is other than uniformly smooth.

15. The laminated element of either of claims 13 and 14 wherein the plastic core element includes fiber reinforcement.

16. The laminated element of any of the preceding claims wherein the core element includes at least one inter-engagement element for inter-engaging the outer surface element.

17. The laminated element of claim 16 wherein the at least one inter-engagement element is a boss.

18. The laminated element of either of claims 16 and 17 wherein the at least one inter-engagement element has a profile that is at least one of circular, polygonal and asymmetric.

19. The laminated element of any of the preceding claims wherein the laminated element forms a chain bar for a chainsaw.

20. The laminated element of any of the preceding claims wherein a perimeter portion of the core element forms a first side of a flow channel and a perimeter portion of a second core element forms a second side of the flow channel and wherein the laminated element includes a connecting structure connecting between the first and second sides of the flow channel.

21. The laminated element of claim 20 wherein the connecting structure includes weakened for easing severance of the connecting structure from the core elements.

22. The laminated element of any of claims 20 and 21 wherein the connecting structure is positioned external to a perimeter of the laminated element.

23. The laminated element of any of claims 20 and 21 wherein the connecting structure is positioned internal to a perimeter of the laminated element.

24. The laminated element of any of claims 20-23 wherein the connecting structure includes a portion positioned internal to a perimeter of the laminated element and a portion external to a perimeter of the laminated element.

25. The laminated element of claim 24 wherein the portion of the connecting structure internal to a perimeter of the laminated element is internal to the passageway.

26. The laminated element of any of claims 20-25 wherein the flow channel is a water flow channel extending the full thickness of the core elements.

27. The laminated element of any of claims 20-26 further including a chain extending around a perimeter of the laminated element and a sprocket, and wherein the flow channel includes a plurality of flow channels, wherein a first flow channel extends to the chain and a second flow channel extends to the sprocket.

28. The laminated element of claim 27 wherein the second flow channel extends into a plane of the outer surface element.

29. The laminated element of claim 28 further including a cover element fixed to the outer surface element covering a portion of the second flow channel.

30. The laminated element of any of claims 20-29 wherein the flow channel includes a curved side wall.

31. The laminated element of claim 30 wherein the flow channel including a curved side wall forms an inlet flow channel

32. The laminated element of either of claims 30 and 31 further including a central flow channel extending along a length of the laminated element.

33. The laminated element of any of claims 20-32 further including at least one flow diversion device in a flow channel.

34. The laminated element of claim 33 wherein the at least one flow diversion device is spaced apart from opposite sides of walls of the flow channel.

35. The laminated element of any of claims 33-34 wherein the at least one flow diversion device is placed adjacent an inlet of the flow channel.

36. The laminated element of any of claims 33-35 wherein the flow channel includes a linear portion and the flow diversion device is positioned within the linear portion.

37. The laminated element of any of claims 33-36 wherein the flow diversion device includes an upstream portion and a downstream portion wider than the upstream portion.

38. The laminated element of any of claims 33-37 further including at least one flow control valve.

39. The laminated element of claim 38 wherein the at least one flow control valve is configured to prevent backflow.

40. The laminated element of either of claims 38 and 39 wherein the at least one flow control valve is positioned adjacent an inlet to the flow channel.

41. The laminated element of any of claims 38-40 wherein the at least one flow control valve is a passive flow control valve.

42. The laminated element of any of claims 38-41 wherein the at least one flow control valve is configured to be set by at least one of manually, hydraulically, and electronically.

43. A laminated element having a peripheral edge surface for supporting a tool component, the laminated element comprising a nonmetal core element and an outer surface element at least partly coextensive with the core element wherein the core element includes a perimeter extending around the core element and wherein the perimeter is formed by laser cutting.

44. The laminated element of claim 43 wherein the plastic core element includes a relatively flat surface where in the flat surface is other than uniformly smooth.

45. The laminated element of either of claims 43 and 44 wherein the plastic core element includes fiber reinforcement.

46. The laminated element of any of claims 43-45 wherein the core element includes at least one inter-engagement element for inter-engaging the outer surface element.

47. The laminated element of claim 46 wherein the at least one inter-engagement element is a boss.

48. The laminated element of either of claims 46 and 47 wherein the at least one inter-engagement element has a profile that is at least one of circular, polygonal and asymmetric.

49. The laminated element of any of the preceding claims 43-48 wherein the laminated element forms a chain bar for a chainsaw.

50. A laminated element having a peripheral edge surface for supporting a tool component, the laminated element comprising a nonmetal core element and an outer surface element at least partly coextensive with the core element wherein the core element includes a perimeter extending around the core element and wherein the perimeter is formed by laser cutting.

51. The laminated element of claim 50 wherein the plastic core element includes a relatively flat surface where in the flat surface is other than uniformly smooth.

52. The laminated element of either of claims 50 and 51 wherein the plastic core element includes fiber reinforcement.

53. The laminated element of any of claims 50-52 wherein the core element includes at least one inter-engagement element for inter-engaging the outer surface element.

54. The laminated element of claim 53 wherein the at least one inter-engagement element is a boss.

55. The laminated element of either of claims 53 and 54 wherein the at least one inter-engagement element has a profile that is at least one of circular, polygonal and asymmetric.

56. The laminated element of any of the preceding claims 50-55 wherein the laminated element forms a chain bar for a chainsaw.

57. A laminated chain bar comprising at least first and second discrete or spaced apart core elements and wherein a first wall of the first core element and a second wall of the second core element are positioned opposite each other and define a flow channel between them and further including at least one engagement element on the first core element for engaging with an adjacent structure.

58. The chain bar of claim 57 wherein the at least one engagement element engages with the outer surface element.

59. The chain bar of claim 58 wherein the at least one engagement element is a boss.

60. The chain bar of either of claims 58 and 59 wherein the at least one engagement element has a profile that is at least one of circular, polygonal and asymmetric.

61. The chain bar of any of the preceding claims 57-60 wherein the at least one engagement element is a connecting structure connecting between the first and second sides of the flow channel.

62. The chain bar of claim 61 wherein the connecting structure includes weakened for easing severance of the connecting structure from the core elements.

63. The chain bar of any of claims 61 and 62 wherein the connecting structure is positioned external to a perimeter of the laminated element.

64. The chain bar of any of claims 61 and 62 wherein the connecting structure is positioned internal to a perimeter of the laminated element.

65. The chain bar of any of claims 61-64 wherein the connecting structure includes a portion positioned internal to a perimeter of the chain bar and a portion external to a perimeter of the laminated element.

66. The chain bar of claim 65 wherein the portion of the connecting structure internal to a perimeter of the chain bar is internal to the passageway.

67. The chain bar of any of claims 61-66 wherein the flow channel is a water flow channel extending the full thickness of the core elements.

68. The chain bar of any of claims 61-67 further including a chain extending around a perimeter of the chain bar and a sprocket, and wherein the flow channel includes a plurality of flow channels, wherein a first flow channel extends to the chain and a second flow channel extends to the sprocket.

69. The chain bar of claim 68 wherein the second flow channel extends into a plane of the outer surface element.

70. The chain bar of claim 69 further including a cover element fixed to the outer surface element covering a portion of the second flow channel.

71. The chain bar of any of claims 61-70 wherein the flow channel includes a curved side wall.

72. The chain bar of claim 71 wherein the flow channel including a curved side wall forms an inlet flow channel

73. The chain bar of either of claims 71 and 72 further including a central flow channel extending along a length of the laminated element.

74. The chain bar of any of claims 61-73 further including at least one flow diversion device in a flow channel.

75. The chain bar of claim 74 wherein the at least one flow diversion device is spaced apart from opposite sides of walls of the flow channel.

76. The chain bar of any of claims 74-75 wherein the at least one flow diversion device is placed adjacent an inlet of the flow channel.

77. The chain bar of any of claims 74-76 wherein the flow channel includes a linear portion and the flow diversion device is positioned within the linear portion.

78. The chain bar of any of claims 74-77 wherein the flow diversion device includes an upstream portion and a downstream portion wider than the upstream portion.

79. The chain bar of any of claims 74-78 further including at least one flow control valve.

80. The chain bar of claim 79 wherein the at least one flow control valve is configured to prevent backflow.

81. The chain bar of either of claims 79 and 80 wherein the at least one flow control valve is positioned adjacent an inlet to the flow channel.

82. The chain bar of any of claims 79-81 wherein the at least one flow control valve is a passive flow control valve.

83. The chain bar of any of claims 79-82 wherein the at least one flow control valve is configured to be set by at least one of manually, hydraulically, and electronically.

84. A method of making a chain bar comprising: laser cutting an opening completely through a chain bar core element.

85. The method of claim 84 wherein laser cutting includes laser cutting the opening completely internal to a perimeter of the core element.

86. The method of any of the preceding claims 84-85 further including laser cutting the opening so that the opening has opposing side walls spaced apart from each other a substantially constant distance.

87. The method of any of the preceding claims 84-86 further including laser cutting a serpentine opening.

88. The method of any of the preceding claims 84-87 further including placing adhesive within the opening.

89. The method of any of the preceding claims 84-88 further including fixing the chain bar core element to a side plate.

90. The method of any of the preceding claims 84-89 further including laser cutting a fluid flow channel in the chain bar core element.

91. The method of any of the preceding claims 84-90 further including laser cutting first and second chain bar core elements connected by a removable element.

92. The method of claim 91 further including removing the removable element from the first and second chain bar core elements.

93. The method of claim 92 further including removing the removable element after fixing the first and second chain bar core elements to a side plate.

94. The method of claim 91 further including laser cutting the first and second chain bar core elements connected by a removable element at a perimeter portion of the first and second chain bar core elements.

95. The method of claim 91 further including laser cutting the first and second chain bar core elements connected by a removable element wherein the removable element is connected at positions interior to an outer perimeter of the first and second chain bar core elements.

96. The method of any of the preceding claims 84-95 further including forming at least one engagement element to be part of the chain bar core element for engaging a complementary element on chain bar side plate.

97. The method of claim 96 further including registering the chain bar core element with the chain bar side plate.

98. The method of claim 97 further including registering the chain bar core element with the chain bar side plate through registration pins.

99. The method of any of the preceding claims 84-98 further including forming a least one flow channel in the chain bar core element extending completely through the thickness of the chain bar core element.

100. The method of claim 99 wherein the at least one flow channel is formed to include first and second walls defining sides of the flow channel and where in both of the first and second walls are curved for adjusting flow in a direction of flow.

101. The method of claim 99 further including forming a flow diversion element adjacent an inlet.

102. The method of claim 101 further including forming the flow diversion element spaced from the side walls of the flow channel.

103. The method of any of the preceding claims 84-99 further including forming a flow channel and a side plate at a location adjacent a portion of the flow channel in a chain bar core element.

104. A method of forming a chain bar comprising fixing a chain bar core having laser cut openings therein to a first side plate on a first side of the chain bar core and fixing a second side plate to an opposite side of the chain bar core.

105. The method of claim 104 wherein the chain bar core includes first and second core elements connected to each other with a removable tab and further including removing the removable tab.

106. The method of claim 105 further including removing the removable tab from points on the first and second core elements within a flow channel.

107. The method of any of the preceding claims 104-106 further including positioning a sprocket adjacent an end of the chain bar core and adjacent a flow channel.

108. The method of claim 107 further including applying a cover at a side plate opening to form a flow channel to a portion of the sprocket.

109. The method of any of the preceding claims 104-108 further including inserting a flow valve in the core.

110. The method of any of the preceding claims 104-109 further including fixing the chain bar core to the first side plate using adhesive.

111. A chain bar assembly for a chainsaw, the chain bar assembly including at least one side plate and a core element wherein the at least one side plate and a core element helped to define a channel for receiving and guiding a chain, and a light source adjacent the at least one side plate and supported by at least one of the at least one side plate and the core element.

112. The chain bar assembly of claim 111 where the light source is an LED light source mounted in and supported through an opening in the at least one side plate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is an upper right isometric view of a chain bar assembly in accordance with one example described herein.

[0023] FIG. 2 is a top plan view of the chain bar assembly of FIG. 1.

[0024] FIG. 3 is a bottom plan view of the chain bar assembly of FIG. 1.

[0025] FIG. 3A is a partial detailed view of an LED light source on a side of the chain bar assembly of FIG. 3.

[0026] FIG. 4 is an exploded view of the chain bar assembly of FIG. 1.

[0027] FIG. 5 is a front elevation view of a core element of the chain bar assembly of FIG. 1.

[0028] FIG. 6 is a top plan view of the core element of FIG. 5.

[0029] FIG. 7 is a bottom plan view of the core element of FIG. 5.

[0030] FIG. 8 is a detailed view of a portion of the side of the chain bar core of FIG. 5 showing upper and lower bosses and a fluid flow channel.

[0031] FIG. 9 is a detailed view of a portion of the side of the chain bar core of FIG. 5 showing the nose end portion of the core.

[0032] FIG. 10 is a partial cross-sectional view of the core of FIG. 5 taken along line 10-10 of FIG. 6.

[0033] FIG. 11 is an isometric view of the core of FIG. 5.

[0034] FIG. 12 is a detailed view of a portion of the core of FIG. 11.

[0035] FIG. 13 is a right side view of the chain bar core of FIG. 5.

[0036] FIG. 14 is a detail of a top plan view of the chain bar core of FIG. 6.

[0037] FIG. 15 is a side elevation view of a flow valve in the chain bar shown in FIG. 4.

[0038] FIG. 16 is a top plan view of the valve of FIG. 15.

[0039] FIG. 17 is a cross-sectional view of a right end of a chain bar assembly omitting the nose sprocket.

[0040] FIG. 18 is a top plan view of a chain bar core according to another example described herein.

[0041] FIG. 19 is a detailed view of a portion of the core of FIG. 18.

DETAILED DESCRIPTION

[0042] This specification taken in conjunction with the drawings sets forth examples of apparatus and methods incorporating one or more aspects of the present inventions in such a manner that any person skilled in the art can make and use the inventions. The examples provide the best modes contemplated for carrying out the inventions, although it should be understood that various modifications can be accomplished within the parameters of the present inventions.

[0043] Examples of tool components and of methods of making and using the tool components are described. Depending on what feature or features are incorporated in a given structure or a given method, benefits can be achieved in the structure or the method. For example, tool components using fluid for cooling may achieve better cooling and longer lifetime. Cutting tool components may also benefit from lighter-weight components, lower-cost and reduced wear.

[0044] Tool components that use water for cooling and/or lubrication may benefit also from one or more features described, for example reducing the possibility of corrosion. Improved corrosion prevention characteristics help component life and promote tool integrity.

[0045] Tool components that use water for cooling and/or lubrication may benefit also from one or more features described, for example reducing the possibility of fluid pressure variations adversely affecting the integrity of the tool. Improved fluid pressure characteristics lead to more predicable operation and also promotes tool integrity.

[0046] In tool components similar to chain bar configurations, one or more aspects of the examples described may allow better cooling and heat transfer, and improved tool performance. By way of further example, the wear rate may be reduced.

[0047] These and other benefits will become more apparent with consideration of the description of the examples herein. However, it should be understood that not all of the benefits or features discussed with respect to a particular example must be incorporated into a tool, component or method in order to achieve one or more benefits contemplated by these examples. Additionally, it should be understood that features of the examples can be incorporated into a tool, component or method to achieve some measure of a given benefit even though the benefit may not be optimal compared to other possible configurations. For example, one or more benefits may not be optimized for a given configuration in order to achieve cost reductions, efficiencies or for other reasons known to the person settling on a particular product configuration or method.

[0048] Examples of several tool configurations and of methods of making and using the tool components are described herein, and some have particular benefits in being used together. However, even though these apparatus and methods are considered together at this point, there is no requirement that they be combined, used together, or that one component or method be used with any other component or method, or combination. Additionally, it will be understood that a given component or method could be combined with other structures or methods not expressly discussed herein while still achieving desirable results.

[0049] It should be understood that terminology used for orientation, such as front, rear, side, left and right, upper and lower, and the like, are used herein merely for ease of understanding and reference, for example with reference to views in the drawings, and are not used as exclusive terms for the structures being described and illustrated.

[0050] A tool component in the form of a chain bar 100 (FIGS. 1-4) is formed as a laminate of two or more components for supporting a cutting chain. The chain bar can be used as part of a chainsaw for cutting wood, concrete or other workpieces, as would be known to one skilled in the art. The assembly and use of a chainsaw with chain bars are well known to those skilled in the art and will not be considered in detail. However, it should be understood that the chain bars described herein can be used with a number of chainsaw configurations as would be appreciated by one skilled in the art.

[0051] The chain bar 100 includes a first or top (as viewed in FIGS. 1 and 4) side plate 102 and a second or bottom side plate 104 (as viewed in FIG. 4) forming with a core 106 a laminated chain bar. The chain bar 100 by a chainsaw motor at a mounting end 108 having a mounting and support slot 110, a drive sprocket area 112 for accommodating a drive sprocket and a pair of fluid inlet openings 114. The fluid inlet openings 114 receive fluid such as water for cooling the chain bar and cooling and lubricating the chain bar groove 116 that supports and guides the cutting chain (not shown), and for cooling and lubricating the nose sprocket 118. Additionally, any fluid exiting the chain bar in the area of the cutting chain also cools and lubricates the cutting chain. Because the chain bar 100 is reversible, two fluid inlet openings 114 are provided, only one of which is used at any given time for supplying fluid to the chain bar. The other of the fluid inlet openings receives a chain tightening mechanism to adjust the chain tension. The chain bar laminate assembly is formed so that the chain bar groove 116 has the conventional configuration.

[0052] In the example of the chain bar 100 shown in FIGS. 1-12, the chain bar includes a plurality of inter-engagement elements. The inter-engagement elements help to laminate the components of the chain bar to form the final chain bar assembly. The inter-engagement elements help to register adjacent planar components relative to each other. They also help to strengthen the structure, for example by improving the sheer strength of the laminate. In the present examples, the inter-engagement elements are formed from complementary elements in the outer plate 102 and 104 with components in the core 106. In the present example, the inter-engaging elements include a plurality of bosses 120 distributed substantially symmetrically about a central longitudinal axis bisecting the mounting and support slot 110. As shown in FIGS. 1-3, the bosses 120 extend into the side plates 102 and 104. The bosses are also shown in FIGS. 5-10. The bosses extend substantially outward from the core 106, and each of the bosses extend in one direction from the corresponding side of the core 106 opposite a similarly located and configured boss extending outward from the opposite surface, except for the pair of bosses at the nose end of the core 106. The bosses 120 at the nose end are positioned on the core 106 to extend only from the top surface, as viewed in FIG. 5.

[0053] The bosses 120 form part of inter-engagement elements to improve the assembly and the structural integrity of the chain bar. Each of the upper and lower side plates 102 and 104 include openings 122 complementary to the respective bosses on the core 106. The openings and the bosses provide registration for adjacent layers and also improved sheer strength for the chain bar. The inter-engagement elements can be shaped to be circular, polygon, asymmetric or other configurations complementary to each other. Other structures in the laminate may also be complementary to each other. While all of the bosses are shown as being located on the core 106 and all of the complementary openings on the first and second side plates 102 and 104, it should be understood that all of the bosses can be on the side plates, or some on the side plates and some on the core with respective complementary inter-engagement elements positioned as appropriate.

[0054] The nose sprocket 118 is a conventional sprocket for supporting the chain. The sprocket is supported for movement on bearings 124 (FIG. 4) about a hub 126 secured between the first and second plates 102 and 104 in the conventional manner. The bearings and the sprocket are cooled with fluid from the fluid inlet openings 114.

[0055] The first side plate 102 in the present example is substantially flat on both sides and includes the openings as indicated. The second side plate 104 is also substantially flat and substantially the same thickness as the first side plate 102, and includes the openings as indicated. In addition to the slot 110, water inlet openings 114, the complementary openings 122 and the openings for securing the nose sprocket, the second side plate 104 includes an opening 128 (FIGS. 3-4) for receiving and supporting a portion of the core 106, described more fully below. The opening 128 provides space for the portion of the core 106 to extend out of the plane of the core. The opening 128 is substantially oval in the present example. The first and second side plates in the present examples are metal, as in conventional side laminates.

[0056] The core 106 (FIGS. 4-12) has a substantially flat bottom surface 130 except for a projection in the form of an outlet manifold 132 (FIGS. 5-7 and 9-10). The outlet manifold 132 extends into the oval opening 128 in the second side plate 104, as described more fully below. The bosses 120 extend substantially normal to the respective surface of the core 106, and our substantially circular in the present examples. The core includes respective water inlet openings 134, corresponding to the water inlet openings 114. The sides of the core other than the distal portion corresponding to the outlet manifold 132 conform substantially to the site configurations of existing chain bar cores, for supporting a cutting chain. Additionally, except for the bosses 120, the outlet manifold 132 and the flow channels described more fully herein, the thickness of the chain bar core 106 is substantially similar to existing chain bar cores.

[0057] The core 106 may be formed from a number of materials, including metal, plastic, composite materials and the like. In the present example, the core is formed from a fiber reinforced plastic. In one configuration, the core has good strength characteristics in compression, and the bosses provide good sheer strength. The plastic core is easily formed through conventional molding techniques having the configurations described herein.

[0058] The core includes an inlet manifold area 136 (FIGS. 6 and 11) with an inlet channel 138 corresponding to each of the inlet openings 134. The inlet channel 138 has a relatively large cross-sectional area for flow and has a relatively gradual curvature to a flow junction 140. As in substantially all of the flow channels of the chain bar in the present example, the flow cross-sectional area is determined by the depth and width of the flow channel formed into plastic core. The remaining side of the flow channel is closed by the adjacent first plate 102 and the adhesive (not shown) between the two. The flow junction 140 extends from an apex point 142 to an exit area 144, at which point fluid flow continues down a substantially central channel 146, as described more fully below. The gradual curvature of the flow inlet to the junction 140 has a substantially constant radius of curvature to the junction, and minimizes abrupt bends or sharp corners. The cross-sectional flow area of each inlet channel 138 is substantially constant from the respective inlet opening 134 to the apex 142.

[0059] The apex point 142 includes an opening 148 for receiving and supporting a flow valve 150 (FIGS. 4 and 15-16). The flow valve 150 pivots freely in the junction area 140 is a function of the direction from which fluid flow is coming. The flow valve 150 serves as a backflow valve reducing the amount of fluid flowing from the inlet channel 138 into the opposite inlet channel 138 (not presently in use for fluid flow). The flow valve also promotes better flow in the remainder of the channel, for example by reducing flow eddies or cavitation.

[0060] The central channel 146 extends substantially along a medial or longitudinal axis of the chain bar core. The flow cross-sectional area gradually decreases in the distal direction to the distal end and the outlet manifold 132. The cross-sectional flow area decreases in width but not substantially in depth out to the distal end portion of the core.

[0061] Considering the various flow paths in further detail, each side of the core from the media line includes to flow branches 152 and 153, each of which branch again before reaching the lateral edge 154 of the core forming the outer perimeter of the core. Each of the respective branches have respective flow cross-sectional areas less than the upstream flow area from which it came, to maintain flow pressure and velocity for example. As shown in FIG. 14, a first branch 152 from the central channel 146 extends substantially straight at an angle from the central channel to a second smaller branch 156 and to a still smaller branch 158 terminating at an outlet port 160. The second smaller branch 156 terminates in a further outlet port 162 (FIGS. 5-6 and 8) further along the perimeter of the core from the outlet port 160. A similar flow channel arrangement is on the opposite side of the central channel, including with comparable cross-sectional flow areas. The flow branches 153 downstream from the first pair of flow branches 152 have a similar layout but smaller flow cross-sectional areas.

[0062] As the central channel 146 approaches the distal end of the core, the cross-sectional flow area continues to decrease to a third flow diversion 164, in the present example. Respective side flow branches 166 having a smaller cross-sectional flow area than the flow branches 152 and 153, respectively, terminate at respective flow outlets 168 (FIGS. 6 and 9). The side flow branches 166 extend away from a flow diversion element 170 (FIGS. 6, 10, 11-13 and 17). The flow diversion element 170 may be an island, flow channel projection or block or some other element for diverting fluid flow. The flow diversion element 170 helps to promote laminar flow, helps to do for fluid flow to the side perimeter 154 of the chain bar core, and in the present example through surface tension and pressure promotes fluid flow to the nose sprocket assembly. The flow diversion element 170 includes a pair of substantially concave upstream flow surfaces 172 and a pair of downstream slightly convex surfaces 174, forming a somewhat elongated diamond-shaped island. The distal flow diversion element helps to maintain flow pressure at the distal end portion of the core.

[0063] Upstream flow islands or flow diversion elements may also be included. For example, flow diversion elements 176 (FIG. 6) are positioned substantially across the openings of the flow branches 152. These flow diversion elements 176 are narrower than the flow diversion element 117 downstream. The diversion elements 176 promote laminar flow and direct flow. The flow diversion element 176 on the opposite side of the flow Inlet channel 138 from which fluid flows helps to direct flow from that side, as does the flow valve 150. For example, the flow diversion element 176 redirects fluid flow from the Inlet channel 138 along the central channel so that the newly incoming fluid flow from the opposite side inlet channel does not flow predominantly out the opposite flow branch 152. Additionally, the opposite flow diversion element 176 may help to encourage flow into the respective flow branch. Other flow diversion elements may be placed as desired to encourage or promote a desired flow pattern. Additionally, further flow outlet ports may be included in the core to improve fluid flow to the cutting chain.

[0064] The outlet manifold 132 at the distal end portion of the core 106 includes planar panel portions 180 and 182 distal of the flow channels 166. The panel portions 180 and 182 extend substantially in the plane of the core. Bosses 120 extend upward from the respective panel portions (FIG. 12). The panel portions 180 and 182 extend distally to respective end surfaces 184 adjacent the nose sprocket.

[0065] The main flow channel leaves the diamond-shaped diversion element 170 and continues toward the nose sprocket and becomes deeper below the upper surface of the planar portions 180 and 182. The distal flow channel 186 (FIG. 12) has a depth that increases to be greater than the thickness of the planar portion of the core and into the outlet manifold 132, including that portion of the outlet manifold that extends into the plane of the second side plate 104 through the oval opening 128 (FIG. 4). The distal flow channel 186 permits fluid flow from the main flow channel underneath the nose sprocket to the bearings 124 and to the side of the nose sprocket 118. The outlet manifold includes a protruding plate 188 that extends into the oval opening. The distal flow channel 186 is formed in part in the protruding plate 188 while still being formed as part of the core 106. The distal flow channel 186 continues within the protruding plate 188 with a substantially flat bottom surface 192 and upwardly-curving surface 192 at the end of the flow channel. The upwardly-curving surface 192 forces the fluid to flow against the nose sprocket and the bearings. Other configurations of the core and/or outlet manifold can direct fluid in the area of the sprocket and bearings as desired.

[0066] The water flow channel surfaces are formed substantially smooth with a smooth finish. The remaining portions of the core 106, when formed from a plastic material, include a textured finish. The finish is a random texture that increases the surface area for bonding using adhesive or a bonding agent. The texture can be formed with a plastic part is molded, for example, or after. Molding can include a texture, such as through the technique applied by Mold-Tech. Other structures and methods may also be used for increasing bonding strength, such as cuts in the plastic or other core material described more fully herein.

[0067] The chain bar can be assembled from the first and second side plate and the core 106 by applying adhesive, for example to the second side plate over those surfaces where the core will be substantially opposite and in contact with the side plate but for the existence of the adhesive. The core is then placed against the second side plate using the bosses and the respective openings 122 for registration and alignment. The flow valve and nose sprocket assembly are placed in their respective positions relative to the core. The first side plate 102, with adhesive on that part of the surface that will come into contact with the core and bosses 120, is then placed against the core with the bosses 120 and registration with the openings 122. The nose sprocket and the fastening holes in the side plates are aligned as is conventional. The adhesive can then be cured to secure the laminate. It is noted that a plastic core 106 can be used to resist corrosion of the second side plate 104, and the adhesive on the first side plate 102 can also inhibit corrosion of the first side plate. Additionally, the adhesive can be cured with the first side plate down or on the bottom of the chain bar assembly during curing so that adhesive from the first side plate does not flow upward into the flow channels.

[0068] In another example of a chain bar core that can be used with the side plates as described to form a chain bar assembly, a core 200 (FIG. 18) includes flow channels 202 that are formed completely through the entire thickness of the core. (The circles in FIG. 18 corresponding to the fluid inlet openings would not be present in the core, and the post for receiving the fluid valve 150 in the example of FIG. 4 would be supported on one of the adjacent side plate. Additionally, any islands or flow diversion elements that would be freestanding in a flow channel would be supported by one or both adjacent side plates.) The core can be formed from metal, plastic or other materials, for example by laser cutting or other forming technique.

[0069] In one example, the water channels are formed by cutting and connecting tabs such as tab 204 (FIG. 19) is maintained in the core to keep the various segments of the core coupled to each other and in the desired arrangement prior to assembly with the adjacent side plates. In the present example, the tab 204 includes a bridge portion 206 extending between adjacent spaced apart sidewalls of the corresponding flow channel and a manipulating portion 208. In the present example, the bridge portion 206 is internal to the perimeter of the core. In other examples, the bridge portion can be connected to the perimeter surface elements of the spaced apart segments forming a flow channel. The manipulating portion 208 can be used to remove the bridge portion 206 at the desired time, for example when the core 200 has been applied to an adjacent side plate, for example through adhesive. Each of the outlet ports can include respective tabs for maintaining the various otherwise separate core segments in their desired orientation with respect to each other. Additionally, tabs can be used to position islands or flow diversion elements as desired until such time as the core elements are positioned relative to a side plate. When a core assembly is ready to be applied to an adjacent side plate, for example through adhesive, the core and the side plate can be combined and the tabs removed. Thereafter, the opposite side plate can be applied to form the assembly and the adhesive cured. In this example, the depth of the flow channels extends the entire thickness of the core. In this example also, if desired, the portions of the outlet manifold 132 in the embodiment of FIGS. 4-17 outside the plane of the core can be omitted.

[0070] In any of the core examples described herein, flow channels and other core components can be formed by cutting, for example laser cutting. Additionally, the complementary openings 120 as well as other openings such as the channel 110 can be formed in the side plates by laser cutting or other cutting means. A core can also have laser cut or other formed openings through the core to assist in strengthening the resulting chain bar. For example, in the example of the core 200 shown in FIG. 18, serpentine laser cut lines 210 are formed in the core 200 forming passageways extending through the thickness of the core. The lines 210 are each a closed-circuit, and do not extend to an outer perimeter of the core. These lines are nonlinear longitudinally and transversely of the core. The lines in the present example are noncircular, and spaced apart sidewalls have substantially the same spacing. Additionally, the spacing between sidewalls is substantially the same from one end of the opening to the other. On assembly, for example with an adhesive to bond the layers together, adhesive enters the openings of the lines 200, and may even extend completely through the thickness of the core, and between the spaced apart sidewalls. Such adhesive pocketed cuts or lines improve the sheer strength of the chain bar.

[0071] In any of the core examples described herein, lighting components may also be included or otherwise adapted for illumination through the chain bar for illuminating the surrounding area. For example, LEDs can be mounted on the side plates, for example three per side, and set into respective openings in the side plates (representative single LEDs 212 and 214 of which are shown in FIGS. 2 and 3, respectively, and LED 214 is shown in an opening 216 more easily seen in the detail FIG. 3A). In addition, or alternatively, light sources in the chainsaw motor housing can illuminate the chain bar, and a translucent side plate or side plates can transmit light from such light sources to the surrounding area. Translucent materials may include polycarbonate and Lexan. Current may be provided to LEDs or other light sources through conductors embedded in the core such as a plastic core, or in flow paths in the core. Current may be generated by a generator producing current arising from fluid flow past the generator. Alternatively, a battery or other energy source may be embedded in the chain bar, for example in the core or a side plate. Lighting can be turned on through a manually accessible switch, or a detent switch adjacent the chain that is activated through chain motion. Alternatively, power can be obtained from the chainsaw, such as through a spark plug or other electrical source.

[0072] Having thus described several exemplary implementations, it will be apparent that various alterations and modifications can be made without departing from the concepts discussed herein. Such alterations and modifications, though not expressly described above, are nonetheless intended and implied to be within the spirit and scope of the inventions. Accordingly, the foregoing description is intended to be illustrative only.