JPH0444532A - Abrasion-resistant offset side bar chain - Google Patents

Abstract

PURPOSE: To increase wear resistance to a chain by providing a sidebar having a first edge to at least one of chain links and making high frequency hardening hold in at least one of the front end and rear end of the sidebar in a state to adjoin the first edge. CONSTITUTION: A chain 16 is constituted of a sidebar 26 including a part mounting a cutter tool 20 thereto and a joint sidebar 30. The joint sidebar 30 is equipped with a first edge 32 coming into slidingly contact with a boom 12, the front end circumference 34, a second (opposite) edge 36 and the rearend circumference 38. In order to increase resistance to wear due to friction, high frequency hardening is made along a part 48 extended from the first edge 32. High frequency hardening of parts 50 and 52 respectively extended from the front end circumference 34 and rear end circumference 38 of the joint sidebar 30 are also made. In the case of trenching operation, the boom 12 is lowered, and the chain 16 is driven, contact operation to the ground surface 22 to be excavated by the cutter tool 20 is made.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) The present invention relates to chains, and particularly to chains used in trenchers and other applications.

“ Ditching machines usually have a digging chain supported on a boom. In use, the boom extends forward and downward from the main body, and the digging chain is attached and fixed around the boom.

The g-cutting chain supports a plurality of spaced apart digging or cutting teeth in contact with the surface to be excavated.

During trenching machine operation, as the chain continuously moves along the edge of the boom, the frictional contact between the chain and the boom surface causes wear on the chain links, and the chain and boom contact during trenching. If dirt or gravel gets in between the
The wear increases and worsens.

Furthermore, when the cutter hits an obstacle or hard material during operation of the trencher, backflexing of the chain links is likely to occur as the cutter supported by the link contacts its trenching surface. This backbending of the chain link and cutter not only reduces the effectiveness of the cutter, but also increases the friction between some surfaces of the trencher's chain and boom, causing uneven wear of the chain link. .

Some chain link sidebars are induction hardened at the center of the edges that make sliding contact with the support surface to reduce chain wear, but none of the prior art techniques It does not provide an effective means for reducing chain wear at the front and rear ends of the chain link edges, where the chain link edges are at their maximum.

Accordingly, the present invention provides an offset side bar chain consisting of a plurality of chain links connected together by chain pins.

At least one of the chain links includes a side bar having a first edge supported in sliding contact with a support surface. The first edge is generally straight and extends along the direction of movement of the chain relative to the support surface. The side bar further includes a second edge spaced apart from the first edge and substantially parallel to the first edge, a rear end portion having a first pitch hole therethrough, and a tip end portion having a second pitch hole therethrough. It is equipped with a department. At least one of a leading end and a trailing end of the side bar includes an induction hardening portion adjacent to the first edge.

In the preferred embodiment of the present invention, the induction hardened portion of the side bar further extends between the first edge and a line extending substantially parallel to the first edge.

Furthermore, the original wire is located between the pitch hole and the first edge and is spaced apart from both.

In one aspect of the invention, the sidebars of the chain also have a shape that reduces backbending of the chain links when a cutter tool supported by the chain is loaded.

In the present invention, the chain is used in conjunction with a trencher or transporter.

In another aspect of the invention, the chain is an offset sidebar chain, with each sidebar including the induction hardening extending the entire length of the sidebar and perpendicular to the support surface against which the sidebar slides. 2 extending in the direction
It also includes a metset curve defined by two continuous curved lines.

These and other features and advantages of the invention will be apparent to those skilled in the art from the following detailed description of preferred embodiments of the invention, given by way of example only, with reference to the accompanying drawings in which: FIG.

Stop 1 Referring to FIG. 1, a trencher 10 is shown having a digging boom 12 that pivots about an axis 14 during trenching operations.

A digging chain 16 is attached to the digging boom 12, supported by guide means to one end of the chain loop, and drivingly engaged by a hess block at the other end of the chain loop. In the illustrated embodiment, said guide means are sprockets or guide wheels 18. The chain 16 supports a plurality of cutter tools 20, and when the boom 12 is lowered and the chain 16 is driven during trenching operation, the cutter tools 20 move the surface 20 to be excavated.
Acts on contact.

** During drilling, the chain 16 comes into sliding contact with the drilling boom 12, friction is created between the chain 16 and the lower part 24 of the drilling boom 12, and pressure is applied from the chain 16) to the lower part 24 of the drilling boom 12. .

When the cutter tool 20 contacts the surface 22 to be excavated, the cutter tool tends to backflex the chain links that support them. Referring now to FIG. 2, it can be seen how the chain links wear over time due to the backbend that occurs when the cutter tool 20 contacts the ground surface 22.

The chain 16 of the preferred embodiment of the invention includes a side par 26 that includes a portion to which a cutter tool 20 is attached;
It is configured as a connecting side par 30.

Each coupling side par 30 has a first edge 32 in sliding contact with the boom 12, a leading outer circumference 34, a second (opposing) edge 36, and a trailing outer circumference 38. As can be seen from the figure, the first edge 32 receives a frictional force at a portion close to the outer circumference 34 of the distal end of the connecting side par 30. Similarly, each side par 2 has a portion 2 supporting a cutter tool 20.
6 is a base 29, a first edge 40, a tip outer periphery 42, a second
(opposed) edges 44 and a rear end outer periphery 46.

Although in the drawing (FIG. 4) portions 28 of the side pars 26 extend coplanarly from the base 29, in other embodiments
The portion 28 of the side par 26 may be bent 90° relative to the base 29 or may be separate from the base 29 and welded thereto. As can be seen in Figure 1, the first edge 40 has a portion for supporting a cutter tool. A portion close to the rear end outer circumference 46 of each side par 26 receives frictional force. Also, the outer circumference 34 of the tip end of each side par 30 for connection, and the outer circumference 46 of the rear end of each side par 26 having a portion that supports the cutter tool.
are subjected to frictional forces near the first edges 32 and 40 of each side par.

Referring now to FIG. 3, one of the connecting side pars 30 shown in FIG. 2 is shown in detail. The connecting side parr 30 in the preferred embodiment includes a portion 48 extending from the first edge 32 to provide increased resistance to frictional wear.
The edges are induction hardened. In addition, portions 50 and 52 extending from the front end outer periphery 34 and the rear end outer periphery 38 of the connecting side par 30, respectively, are also induction hardened to increase wear resistance. It continues to section 48.

In some applications, it is contemplated that portion 48 may not be induction hardened.

Pitch holes δ4 are provided near the front end outer periphery 34 and rear end outer periphery 38 of the connecting side pars 30, respectively, and connect each side par to the other side par of a pair of side pars forming one link, and constitute another link of the chain 16. It is possible to attach it to the side par. These pitch holes 54 have their respective centers on an axis 56 parallel to the first edge 32 . Additionally, the pitch hole 54 is spaced from the first edge 32 by a distance that is greater than the distance between the pitch hole and the second edge 36 . This allows for an increase in the thickness of the material and also increases the amount of wear on the chain before it breaks.

As is clear from the figure, the entire induction hardened portion of the side par 30 is spaced apart from the pitch hole 54.

Both side surfaces (the outer periphery of the leading end and the outer periphery of the rear end) 34 and 38 of the connecting side par 30 have an arcuate portion 58 that intersects with the first edge 32.
and 60, as well as arcuate portions 62 and 64 that intersect the second edge 36. Arcs 62 and 64 each have a center of curvature approximately halfway between first and second edges 32 and 36, while arcs 58 and 60 each have a center of curvature below axis 56. In FIG. 3, the arcuate portion 5
8 and 60 each have the first edge 32 than the second edge 36.
It has a center of curvature at a position close to . As a result, the first edge 32 is longer than the second edge 36. A pitch hole 54 penetrating near the rear end outer periphery 38 has a first transverse axis 6
It has a center located on 1. Pitch hole 54 extending near tip outer circumference 34 has a center located on second transverse axis 63 .

Transversals HI 61 and 63 are both perpendicular to said axis 56. The first between the first transverse axis 61 and the rear end outer circumference 38
The distance along edge 32 is between axis 56 and first edge 32 m.
half, more specifically greater than three-fourths, of the vertical distance of
It has been found that this shape reduces chain backbend and thus reduces chain wear.

Referring now to FIG. 4, one of the side bars 26 shown in FIG. 2 having a portion supporting a cutter tool is shown in detail. Side par 26 is induction hardened along a portion 66 extending from first edge 40 to increase resistance to frictional wear. In addition, portions 6 and 70 extending from the tip outer periphery 42 and the rear end outer periphery 46 of the side par 26, respectively, are also induction hardened to increase wear resistance, and the first edge 40 of the side par 26 is
It continues into a portion 66 extending from.

A pitch hole 72 is provided in the base 29 of the side par 26,
These pitch holes 72 are arranged so that the shaft 7 is spaced from the first edge 40 by a distance equal to the distance that the shaft 56 is spaced from the first edge 32 of the connecting side par 30 shown in FIG.
4 with their respective centers along. Also, bolt hole 7
3 are provided on portions 28 of the side pars 26 to allow each cutter tool 20 to be bolted to each side par 26. Alternatively, cutter tool 20 may be welded to side par 26.

Both sides of the side par 26 (tip outer circumference and rear end outer circumference) 42
and 46 are arcuate portions 7 terminating in the first edge 40, respectively.
6 and 78. The arcuate portions 76 and 78 are each spaced apart from the first edge 40 by a distance equal to the distance that the respective centers of curvature of the arcuate portions 58 and 60 are separated from the first edge 32 of the connecting side par 30 shown in FIG. It has a center of curvature.

Illustrated in FIG. 5 is a portion of a chain 116 similar to the chain 16 shown and described with reference to FIGS. Chain 116, which will not be discussed further, differs from chain 16 in that it is an offset side bar chain.

The shape of the side pars 26 and 30 of the chain 116 is such that these side pars 26 and 30 have offset curved portions 190 and 1
92, which are substantially the same as the side pars 26 and 30 of the chain 16, respectively.

That is, the offset curved portion 190
It is formed by two continuous curved lines 190A and 190B extending in a direction perpendicular to the surface 24 with which the side par 26 comes into sliding contact (the lower part of the cutting boom). Similarly, the offset curved portion] 92 is formed by two continuous curved lines 192A and 192B extending in a direction perpendicular to the surface with which the side par 30 makes sliding contact, for example, the surface 24 with which the side par 30 makes contact (the lower part of the S-cutting boom). (See also Figure 7). That is, the side par 26 has a tip 43 that is parallel to the rear end 45 but offset therefrom.

Each curved line 190A and 190B and 192A and 192B is a relatively sharp curve. Curved lines 190A and 19
Side par 26 including 0B and curved lines 192A and 192B
In order to reduce manufacturing costs, it is preferable that the side par 30 including the side par 30 be formed from a cold punched steel plate instead of hot forging.

FIG. 9 shows an embodiment of the invention similar to the embodiment shown in FIG. 5, but in which the offset side bar chains 1]6 are not induction hardened at all. The pitch holes 54 and 72 of the side pars 30 and 26 of the chain 116 shown in FIGS.
2. It is arranged so that the thickness of the material can be increased between 40 and 30 and 26.
The arcuate parts 58, 60, 76 and 78 of (chain 1
6) to reduce the backcurvature of the chain.

Figure 8 shows the
Illustrated is a portion of a chain 216 that is substantially equivalent to the chain illustrated and described in U.S. Pat. Chain 216 differs from the chain illustrated and described in U.S. Pat. 248 is induction hardened. At least one side parr 226 having a cutter tool supporting portion 228 is also induction hardened along a portion 266 extending from the first edge 240 of the side parr 226. Furthermore, the tip 235 and the rear end 23 of the connecting side par 230
Portions 250 and 252 extending from the leading end outer periphery 234 and rear end outer periphery 238 of No. 7, respectively, are induction hardened,
It continues into a portion 248 extending from the first edge 232 of the connecting side par 230 . Similarly, the tip outer periphery 242 and the rear end outer periphery 2 of the tip 243 and the rear end 245 of the side par 226.
Portions 268 and 270, respectively, extending from 46 are also induction hardened to form the first edge 2 of side par 226.
40 continues into a section 266 extending from 40. Induction hardening of both side bars 230 and 226 increases wear resistance. In some applications, the portion 248 is not induction hardened, and only at least one of the leading edge 235 and trailing edge 237 of the connecting side par 230 includes an induction hardened portion 260 or 252 adjacent the first edge 232. It is also possible to do so. Similarly, depending on the use of the part, the part 266 may not be induction hardened, and only at least one of the tip 243 and the rear end 245 of the side par 226 may be induction hardened in the induction hardened part 2 adjacent to the first edge 240.
68 or 270.

That is, the chain 2 in that the side pars 226 and 230 include continuous offset bends 290.292 formed and defined in the same manner as the offset bends 190.192.
] 6 is substantially superior to the chain 116. chain 2
16 is different from the chain 116 in the side par 230.
Pitch holes 254 and 272 of and 226 are not necessarily arranged to increase the thickness of stock material between them and edges 232, 240, respectively (pitch holes 54 and 72 of side pars 30 and 26 of chain 116 are points (positioned to increase the thickness of the material between the pitch hole and both edges 32 and 40 respectively) and the side par 2
30 and 226 arcs 258.260 and 276.278
each do not necessarily reduce the backbend of the chain (the arcuate portions 5 of side pars 30 and 26 of chain 116
8.60 and 76.78 are points (reducing chain backbend).

The chain 16 may be used in an unwi machine or an asphalt stripping machine instead of a trench digging machine, and in this case, the carrying tool or stripping tool can be attached to the tool support part 2 of the side par.
8 can be installed. Further, instead of inserting and fixing bolts into the bolt holes 73, the tools can be attached by another method, such as by welding each tool to the tool support portion 28 of the side par 26.

In the chains 16, 116 and 216 of the illustrated embodiment, every other six pairs of offset sidebars of the chain are extended-height sidebars, each having a tool-supporting portion 28 or 228. Although other configurations are possible, the 81st! l shows a configuration in which a cutter tool 20 is secured to each side of the chain for every other pair of side pars in the extended height of the chain. You can also create a sidebar with an extended height, e.g. each second,
Similarly, the cutter tool 20 may be provided on a third or fourth link or may be spaced apart at other intervals.
etc. may be provided, for example, for each second, third or fourth pair of extended height sidebars, or may be spaced at other intervals - i.e. It is not necessary to support tools for each pair of extended sidebars.

As shown most clearly in FIG. 6, if the tool attached to the extended height sidebar 26 or 226 is a cutter tool 20, the cutter tool may be attached to the extended height sidebar 26 or 226 by means of fastening means such as bolts. At the forward (open) ends of the six (lateral) pairs of sidebars 26 or 226, bushings or spacers are fitted around the bolts for both sidebars to maintain proper spacing between the sidebars. It is fixed in place. On the other hand, six (lateral) pairs of extended height side bars 26 or 226 (closed)
At the end, the cutter tool 20 is attached to only one of the six pairs of side bars by another fastening means such as another bolt, and another spacer is fitted around the other bolt.
0 is fixed away from one sidebar.
(The said side spacers are provided to ensure the distance that the front ends of the six pairs of height extended side bars are offset from the rear ends), that is, the cutter tool 20 is The front ends of the six pairs of side bars 26 or 226 are secured to both side bars to transfer the forces transmitted from the cutter tool 20 to the attached pairs of the cutter tool 20 when the chain is used in a trencher. Cost and weight are reduced by securing the cutter tool 20 to only one sidebar at the rear end of the six pairs, while distributing and equalizing the height of the extended sidebar 26 or 226 to both sidebars. has been reduced.

Although preferred embodiments of the invention have been described above as examples, it will be obvious to those skilled in the art that various modifications can be made.
Accordingly, the scope of the invention should be limited only by the spirit and scope of the claims.

11 Summer Momme 1 As described above, according to the present invention, the chain link which causes maximum wear and tear, which was not solved by the conventional sidebar in which the central part of the edge that makes sliding contact with the support surface is induction hardened, An effective means is provided for reducing chain wear at the leading and trailing ends of the edges.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a groove digging machine embodying the present invention; Fig. 2 is a side view of a part of the chain used in the groove digging machine shown in Fig. 1, with the chain cut away, showing the cutter supported by the chain; Fig. 3 shows a side view of one of the connector sidebars of the chain shown in Fig. 2 in an unweared condition; Show details; 4th
The figure shows in detail a side view of one of the tool supporting sidebars of the chain shown in figure 2 in a non-wear condition;
51st! I is #l shown in Figure 1! The first one that can be used with an i-carriage machine.
A diagram of a broken part of another chain; Figure 6 is the 5th
FIG. 7 is a perspective view of the connector side bar taken out from the part of the chain shown in FIG. 5; FIG. 8 is a plan view of the part of the chain shown in FIG. A side view of a broken portion of a second alternative chain usable in the trencher shown in I; and No. 91! I is 1! shown in Figure 1! Figure 3 is a side view of a broken section of a third alternative chain that can be used in a bending machine; <Explanation of symbols> 10... Trench digging machine, 12... Excavation boom, 16
; 116; 216... Chain, 18... Guide means, 24... Support surface (Ii cutting boom lower part), 26
．． 30;226.230...Sidebar 28...
Height extension (tool support), 32.40; 232
．． 240...first edge, 34.42; 235
(234), 2-43 (242)... tip, 36.
44...2nd edge, 38, 46; 237
(23B), 245 (246)...rear end, 50,
52.68.70; 260.252.268.270・
...Induction hardening part, 54.72; 254.27
2... Pitch hole, 56. 74... Vertical axis, 90, 92; 290, 92... Offset curved portion. Applicant Rex Nord Corporation Agent Yukio Maruyama

Claims (1)

[Claims] 1. An offset sidebar chain consisting of a plurality of chain links integrally connected by a chain pin, wherein at least one of the chain links is supported so as to be in sliding contact with a support surface. a side bar having one edge, the first edge being generally straight and extending along the direction of chain travel relative to the support surface, the side bar further spaced from and generally parallel to the first edge; a second edge, a rear end portion having a first pitch hole therethrough, and a tip end portion having a second pitch hole therethrough, the chain pin is inserted through these pitch holes, and the side bar at least one of the leading end and trailing end includes an induction hardened portion adjacent the first edge, each sidebar of each link including at least one induction hardened sidebar perpendicular to the support surface. An offset side bar chain further comprising a continuous offset curved portion extending in a direction. 2. The induction hardened portion of the side bar further extends between the first edge and a line extending substantially parallel to the first edge when viewed from the side, and the line is connected to the pitch hole and the first edge. 2. The offset side bar chain according to claim 1, wherein the offset side bar chain is located between and spaced apart from both. 3. The offset side bar chain according to claim 1, wherein the induction hardened portion is spaced apart from each pitch hole. 4. The offset sidebar chain according to claim 1, wherein the rear end portion includes an induction hardened portion adjacent to the first edge. 5. The offset side bar chain according to claim 4, wherein the tip portion includes an induction hardened portion adjacent to the first edge. 6. The offset sidebar chain according to claim 1, wherein the first edge has a longer length than the second edge when the moving direction of the chain is defined as a length dimension. 7. The offset sidebar chain according to claim 1, wherein the first pitch hole is closer to the second edge than the first edge. 8. The offset side according to claim 7, wherein the first pitch hole and the second pitch hole each have a center located on a longitudinal axis parallel to the first edge. bar chain. 9. The side bar has a vertical axis parallel to the first edge, and the pitch hole passing through the leading end and the pitch hole passing through the rear end each have centers located on the vertical axis. ,
the longitudinal axis is located closer to the second edge than the first edge; the chain further includes a link supporting a tool; the link supporting the tool has a height extending in a direction transverse to the longitudinal axis; a front end having a through pitch hole having a center on the longitudinal axis and having a through pitch hole that allows connection with another side bar, and a rear end having a through pitch hole having a center on the vertical axis; 2. The offset side bar chain according to claim 1, comprising a side bar having a section. 10. The offset sidebar chain according to claim 1, wherein the offset curved portion is defined by two continuous curved lines extending in a direction perpendicular to the support surface. 11. The offset side bar chain according to claim 1, wherein the side bar is formed of a cold punched steel plate. 12. An offset sidebar chain consisting of a plurality of chain links joined together by a chain pin, the sidebar having a first edge supported so that at least one of the chain links is in sliding contact with a support surface. , the first edge is substantially straight;
a rear end portion extending along the direction of movement of the chain with respect to the support surface, the side bar further having a second edge spaced apart from and substantially parallel to the first edge, and a first pitch hole extending therethrough; , a distal end portion having second pitch holes therethrough, the chain pin is inserted into these pitch holes, and the first pitch hole is located on a longitudinal axis parallel to the first edge in side view. , the side bar has a rear end outer periphery extending between the first edge and the second edge at a rear end thereof, and the center of the first pitch hole is perpendicular to the longitudinal axis. and located on a first transverse axis that intersects the first edge, and a distance along the first edge between the first transverse axis and the rear end outer periphery is equal to the longitudinal axis and the first 1. An offset sidebar chain, characterized in that the sidebar includes a continuous offset curve extending in a direction perpendicular to the support surface, the sidebar being more than half the distance from the edge thereof. 13. The distance along the first edge between the first transverse axis and the trailing edge exceeds approximately three-quarters of the vertical distance between the longitudinal axis and the first edge. 13. The offset side bar chain according to claim 12. 14. The side bar has a front end outer periphery extending between the first edge and the second edge at its front end,
The center of a pitch hole passing through the front end of the side bar is located on the longitudinal axis, and is also located on a second transverse axis spaced apart from and parallel to the first transverse axis, The distance along the first edge between the shaft and the front end outer circumference is approximately the same as the distance along the first edge between the first transverse axis and the rear end outer circumference. An offset side bar chain according to claim 12. 15. A patent characterized in that the rear end outer periphery has a first arcuate portion having a center of curvature located on the first transverse axis and between the longitudinal axis and the first edge. An offset side bar chain according to claim 12. 16. The side bar has a front end outer periphery extending between the first edge and the second edge at its front end,
The center of the pitch hole passing through the front end of the side bar is located on the longitudinal axis, and is also located on a second transverse axis parallel to and spaced from the first transverse axis, and the outer periphery of the front end is located on the longitudinal axis. a second arcuate portion extending from the first edge, the second arcuate portion being located on the second transverse axis and between the longitudinal axis and the first edge; 16. The offset sidebar chain according to claim 15, comprising: 17. The offset sidebar chain of claim 16, wherein centers of curvature on the first and second transverse axes are each closer to the first edge than to the second edge. 18. The offset sidebar chain according to claim 12, wherein the offset curved portion is defined by two continuous curved lines extending in a direction perpendicular to the support surface. 19. The offset side bar chain according to claim 12, wherein the side bar is formed of a cold punched steel plate. 20. An offset side bar for a chain consisting of a plurality of chain links integrally connected by a chain pin, which has a first edge supported so as to come into sliding contact with a support surface and is spaced apart from the first edge. and a substantially parallel second edge, a rear end portion having a first pitch hole therethrough, and a tip end portion having a second pitch hole therethrough, the pitch holes being connected to the side bar by the chain pin. to another sidebar, at least one of the leading end and trailing end including an induction hardening adjacent to the first edge, and extending in a direction perpendicular to the support surface. An offset sidebar further comprising an offset curved portion. 21. The offset side bar chain according to claim 20, wherein the offset curved portion is defined by two continuous curved lines extending in a direction perpendicular to the support surface. 22. The offset side bar according to claim 20, wherein the side bar is formed of a cold punched steel plate. 23. An excavation boom, a driving sprocket provided at one end of the boom, a guide means provided at the other end of the boom, and an offset side rotatably attached to the sprocket and guide means around the boom. a bar chain, the chain comprising a plurality of chain links joined together by a chain pin, and at least one of the chain links supported in sliding contact with the boom. a sidebar having a first edge, the first edge being generally straight and extending along the direction of chain travel relative to the boom, the sidebar further spaced from and generally parallel to the first edge; a second edge, a rear end portion having a first pitch hole therethrough, and a tip end portion having a second pitch hole therethrough, the chain pin is inserted through these pitch holes, and the side bar At least one of a leading end and a trailing end includes an induction hardened portion adjacent the first edge, and each sidebar of each link includes at least one induction hardened sidebar, and each sidebar of each link includes at least one induction hardened sidebar of the boom. A ditch digging machine further comprising a continuous offset curved portion extending in a direction perpendicular to the portion supporting the link when the link is in sliding contact with the boom. 24. The induction hardened portion of the side bar further extends between the first edge and a line extending substantially parallel to the first edge when viewed from the side, and the line is in contact with the pitch hole and the first edge. 24. The groove digging machine according to claim 23, wherein the groove digging machine is located between and spaced apart from both. 25. The trenching machine according to claim 23, wherein the induction hardened portion is spaced apart from each pitch hole. 26. Claim 23, wherein the rear end portion includes an induction hardened portion adjacent to the first edge.
Ditching machine as described in Section. 27. Claim 23, wherein the tip portion includes an induction hardened portion adjacent to the first edge.
Ditching machine as described in Section. 28. When the moving direction of the chain is defined as the length dimension,
24. The trencher of claim 23, wherein the first edge has a greater length than the second edge. 29, the first pitch hole is closer to the second edge than the first edge;
Claim 2 characterized in that it is closer to the edge.
The ditch digging machine according to item 3. 30. The trenching of claim 23, wherein the first pitch hole and the second pitch hole each have a center located on a longitudinal axis parallel to the first edge. Machine. 31. The side bar has a longitudinal axis parallel to the first edge, and the pitch hole passing through the leading end and the pitch hole passing through the rear end each have centers located on the longitudinal axis. , the longitudinal axis is located closer to the second edge than the first edge, and the chain further includes a link supporting a tool, the link supporting the tool extending in a direction transverse to the longitudinal axis. a height extension, a tip having a through pitch hole centered on the longitudinal axis and allowing connection with another sidebar, and a rear end having a through pitch hole having a center on the vertical axis; 24. A trench digging machine according to claim 23, characterized in that it comprises a side bar having an end. 32. A trencher according to claim 31, wherein the offset curve is defined by two continuous curved lines extending perpendicular to the support surface. 33. The groove digging machine according to claim 31, wherein the side bar is formed of a cold punched steel plate. 34. An excavation boom, a driving sprocket provided at one end of the boom, a guide means provided at the other end of the boom, and a chain rotatably attached to the sprocket and the guide means around the boom. a first edge, the chain comprising a plurality of chain links joined together by chain pins, at least one of the chain links being supported in sliding contact with the boom; a side bar having a first edge substantially straight and extending along the direction of chain travel relative to the boom, the side bar further having a second substantially parallel edge spaced apart from the first edge; an edge, a rear end portion having a penetrating first pitch hole, and a tip portion having a penetrating second pitch hole, the chain pin is inserted through these pitch holes, and the first pitch hole is The side bar has a center located on a vertical axis parallel to the first edge in a side view, and the side bar has a rear end outer periphery extending between the first edge and the second edge at the rear end. and the center of the first pitch hole is located on a first transverse axis that is perpendicular to the longitudinal axis and intersects the first edge, and the center of the first pitch hole is located on a first transverse axis that is perpendicular to the longitudinal axis and intersects the first edge, and a continuous offset curve, the distance along the first edge being greater than half the distance between the longitudinal axis and the first edge, and the sidebar extending in a direction perpendicular to the support surface of the boom; A ditch digging machine comprising: 35. The distance along the first edge between the first transverse axis and the trailing edge periphery exceeds approximately three quarters of the vertical distance between the longitudinal axis and the first edge. 35. A trench digging machine according to claim 34. 36, the side bar has a front end outer periphery extending between the first edge and the second edge at a front end thereof;
The center of a pitch hole passing through the front end of the side bar is located on the longitudinal axis, and is also located on a second transverse axis spaced apart from and parallel to the first transverse axis, The distance along the first edge between the shaft and the front end outer circumference is approximately the same as the distance along the first edge between the first transverse axis and the rear end outer circumference. A trench digging machine according to claim 34. 37. The rear end outer periphery has a first arcuate portion extending from the first edge, the first arcuate portion being located on the first transverse axis and intersecting with the longitudinal axis and the first edge. 35. A trench digging machine according to claim 34, characterized in that it has a center of curvature located between. 38, the side bar has a front end outer periphery extending between the first edge and the second edge at a front end thereof;
The center of the pitch hole passing through the front end of the side bar is located on the longitudinal axis, and is also located on a second transverse axis parallel to and spaced from the first transverse axis, and the outer periphery of the front end is located on the longitudinal axis. a second arcuate portion extending from the first edge, the second arcuate portion being located on the second transverse axis and between the longitudinal axis and the first edge; A trench digging machine according to claim 37, characterized in that it has: 39. The trencher of claim 38, wherein centers of curvature on the first and second transverse axes are each closer to the first edge than to the second edge. 40. The trencher of claim 34, wherein the offset curve is defined by two continuous curved lines extending perpendicular to the support surface. 41. The groove digging machine according to claim 34, wherein the side bar is formed of a cold punched steel plate. 42. An excavation boom, a driving sprocket provided at one end of the boom, a guide means provided at the other end of the boom, and an offset side rotatably attached to the sprocket and guide means around the boom. a trench digging machine comprising a bar chain, the chain comprising a plurality of chain links joined together by a chain pin, and at least one of the chain links supported in sliding contact with the boom. a sidebar having a first edge, the first edge being generally straight and extending along the direction of chain travel relative to the boom, the sidebar further spaced from and generally parallel to the first edge; the chain pin is inserted into these pitch holes, and the side bar is said first at the rear end.
a rear end outer periphery extending between an edge and the second edge, the center of a pitch hole passing through the rear end of the side bar is perpendicular to the longitudinal axis and intersects with the first edge; 1
the rear end outer periphery has a first arcuate portion extending from the first edge, the first arcuate portion being located on the first transverse axis and the longitudinal a center of curvature located between the first transverse axis and the trailing edge, and a distance along the first edge between the first transverse axis and the trailing edge is equal to 1 edge, at least one of the leading end and the trailing end of the side bar includes an induction hardened portion adjacent to the first edge, and includes at least one induction hardened portion. each sidebar of each link, including the sidebar of each link, further includes a continuous offset curved portion extending in a direction perpendicular to a portion of the boom that supports the link when the link is in sliding contact with the boom. trench digging machine. 43. The induction hardened portion of the side bar further extends between the first edge and a line extending substantially parallel to the first edge when viewed from the side, and the line is in contact with the pitch hole and the first edge. 43. A ditch digging machine as claimed in claim 42, characterized in that it is located between and spaced apart from both. 44. The groove digging machine according to claim 42, wherein the induction hardening portion is spaced apart from each pitch hole. 45. Claim 42, wherein the rear end portion includes an induction hardened portion adjacent to the first edge.
Ditching machine as described in Section. 46. Claim 42, wherein the tip portion includes an induction hardened portion adjacent to the first edge.
Ditching machine as described in Section. 47. The side bar has a front end outer periphery extending between the first edge and the second edge at its front end,
The center of the pitch hole passing through the front end of the side bar is located on the longitudinal axis, and is also located on a second transverse axis parallel to and spaced from the first transverse axis, and the outer periphery of the front end is located on the longitudinal axis. a second arcuate portion extending from the first edge, the second arcuate portion being located on the second transverse axis and between the longitudinal axis and the first edge; A trench digging machine according to claim 42, characterized in that it has: 48. The trencher of claim 42, wherein centers of curvature on the first and second transverse axes are each closer to the first edge than to the second edge. 49. The trencher of claim 42, wherein the offset curve is defined by two continuous curved lines extending perpendicular to the boom support. 50. The groove digging machine according to claim 42, wherein the side bar is formed of a cold punched steel plate.