JP2006333781A - Dumper member-connecting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dumper member-connecting structure capable of keeping the adhesive strength for sticking a dumper member to an operation rod in high reliability even if a little difference of a fitting clearance between the operation rod and the dumper member is present. <P>SOLUTION: The dumper member 20 of a brush cutter, having a motor at the base terminal part of the operation rod, and the operation rod connected to an attaching cylinder part of the motor through a dumper member 20 has a cylindrical body 21 to be fitted to the base terminal part of the operation rod and an elastic body 31 connected to the outside surface thereof. Two or more recessed parts 22 extending from the base terminal side of the cylindrical body 21 to this side position of the tip part are formed in the inside surface of the cylindrical body 21 at a prescribed interval in the circumferential direction of the cylindrical body 21. The base terminal-side terminal part of the cylindrical body 21 is arranged so as to be protruded from that of the elastic body 31, and a notched part 21b communicating with the recessed parts 22 is formed in the protruded part 21a. When an adhesive is fed to the recessed parts 22 through the notched part 21b, the adhesive flows the recessed parts 22, is expanded on the surface of the base terminal part of the operation rod and is cured to fix the dumper member 20 to the operation rod. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a working part at one end of an operating rod, a motor is disposed at the other end of the operating rod, and a brush cutter, a hedge trimmer, etc. in which the operating rod is connected to a mounting cylinder portion of the prime mover via a damper member. The present invention relates to a damper member connecting structure in a working machine.

  This type of work machine includes a handheld brush cutter. In this brush cutter, a cutting device having a rotary blade is attached to the tip of a normal metal operation rod, the engine is arranged at the base end of the operation rod, and the engine power is arranged in the operation rod. It is configured to transmit to the rotary blade via the transmission shaft. In the mowing work, the operator operates by grasping the handle attached to the operation rod. In such a brush cutter, when the engine is driven, in order to prevent vibration generated from the engine from being transmitted to the handle portion via the attachment tube portion, an elastic body is provided at the joint portion between the operating rod and the attachment tube portion. In general, a damper member provided is interposed.

  Moreover, the attachment method of an operating rod, a damper member, and an attachment cylinder part is generally performed by fastening, and there exists a technique of patent document 1 as the example. The mounting method described in Patent Document 1 is a damper member in which vibration-proof rubber is joined to the outer peripheral surface of a cylindrical holding fitting that is fitted and fastened to a base end portion of an operating rod (in the document, a vibration-proof member). ) Is inserted into the mounting cylinder and fixed to the mounting cylinder with a retaining clip. The retaining clip regulates the removal of the damper member by a portion protruding inward from the retaining groove in a state where the retaining clip is attached to the clip retaining groove provided in the mounting cylinder portion. In addition, a groove extending in the axial direction of the damper member is formed on the surface of the anti-vibration rubber bomb so that the damper member does not rotate with respect to the mounting cylinder part, and a protrusion that engages with the groove is formed on the inner surface of the mounting cylinder part. Provided. As described above, the conventional brush cutter has a problem in that the structure of the portion connecting the damper members is complicated, the number of parts is large, and the weight and cost are increased.

  On the other hand, if the damper member is fixed to the operating rod with an adhesive, it is considered that the connecting structure of the damper member can be simplified, the weight can be reduced, and the increase in cost can be suppressed. In this case, when fixing the damper member with an adhesive, it is preferable to use an adhesive that has high adhesive strength and cures in a short time in consideration of productivity. If such an adhesive is applied to the operation rod in advance, there is a risk that the adhesive will dry and the damper member cannot be fixed before the damper member is inserted into the operation rod. Therefore, after the damper member is inserted in the operation rod in advance, it is necessary to inject and bond an adhesive between them.

JP-A-9-303354

  Thus, when fixing a damper member with an adhesive agent, since the damper member is fitted and inserted in the operating rod, the fitting gap formed between them is generally narrow. Therefore, it is necessary to use an adhesive having a low viscosity, but if the fitting gap of the fitting part between the damper member and the operating rod changes within the range of the dimensional tolerance, variations in the surroundings of the adhesive occur, In particular, when the fitting gap is narrow, the reliability of the adhesive strength is lowered. Further, in a brush cutter that is frequently used in a state where vibration is large, such as in a high-speed rotation speed region exceeding 7000 rpm, there is a risk that the metal operating rod may peel off from the damper member during the mowing operation and become loose.

  In the present invention, when the damper member is fixed to the operating rod with an adhesive, it is required that the reliability of the adhesive strength can be maintained in a high state even if the fitting gap changes depending on the object, and the productivity is high. An object of the present invention is to provide a damper member coupling structure for a working machine that meets such requirements.

  In order to solve such a problem, the present invention provides a working portion at one end of the operating rod, a prime mover at the other end of the operating rod, and the operating rod is attached to the mounting cylinder portion of the prime mover via a damper member. In the connected working machine (for example, the brush cutter 1 in the embodiment), the damper member includes a cylindrical body fitted to the other end portion of the operating rod and an elastic body joined to the outer surface of the cylindrical body. A damper member coupling structure for a work machine to be inserted into a mounting cylinder, wherein a recess extending from the other end side of the cylindrical body to one end side is provided on the inner surface of the cylindrical body, and the low viscosity is supplied to the recess The damper member is fixed to the operating rod by an adhesive that hardens in a short time.

  According to this invention, since the concave portion is provided on the inner surface of the cylindrical body, when the adhesive having a low viscosity and cured in a short time is supplied to the concave portion, the adhesive received in the concave portion is removed from the concave portion. The surface tension spreads so as to ooze out the fitting portion between the operating rod and the cylindrical body. Further, since the recess extends from the other end side of the inner surface of the cylindrical body to one end side, the adhesive easily spreads from the other end side of the fitting portion to the entire area of the one end side, and the range of the adhesive due to variations in the fitting gap. The variation in the thickness is reduced, and bonding can be performed in a short time. Therefore, it is possible to maintain a high reliability of the adhesive strength at which the damper member adheres to the operation rod in a highly productive manner, and there is a risk that the operation rod may peel off from the damper member during the mowing operation. Can be prevented.

  Moreover, the recessed part of this invention is extended from the other end side of a cylindrical body to the near position of one end part, It is characterized by the above-mentioned.

  According to this invention, the concave portion extends from the other end side of the cylindrical body to a position before the one end portion, and the tip end portion of the concave portion does not reach the one end portion of the cylindrical body. There is no risk of leakage from the one end, and the adhesive supplied to the recess can be supplied to the entire fitting portion between the operating rod and the cylindrical body without waste. As a result, it is possible to reliably maintain the high reliability of the adhesive strength between the operating rod and the damper member.

  Further, a plurality of recesses according to the present invention are provided with a predetermined interval in the circumferential direction of the cylindrical body.

  According to the present invention, by providing a plurality of recesses with a predetermined interval in the circumferential direction of the cylindrical body, the adhesive can be easily spread throughout the fitting portion between the operating rod and the cylindrical body, and the operating rod and the damper member. It is possible to more reliably maintain the high reliability of the adhesive strength. In particular, by providing the concave portions evenly at three places, a higher effect can be obtained with a small number of concave portions.

  Furthermore, the present invention is characterized in that a communication recess is provided on the inner surface of the cylindrical body so as to communicate between the recesses adjacent in the circumferential direction of the cylindrical body.

  According to the present invention, by providing the communication concave portion that communicates between the concave portions adjacent to each other in the circumferential direction of the cylindrical body on the inner surface of the cylindrical body, the adhesive receiving region extends over the entire cylindrical body and between the concave portions. Since the adhesive is received evenly, it becomes easier for the adhesive to spread evenly over the entire fitting part of the operation rod and the cylindrical body, and it is further ensured that the reliability of the adhesion strength between the operation rod and the damper member is high. Can be.

  Further, the present invention is characterized in that the other end side end portion of the cylindrical body of the damper member protrudes from the other end side end portion of the elastic body, and a notch portion communicating with the concave portion is provided in the protruding protrusion portion. .

  According to this invention, by providing the cutout portion communicating with the concave portion at the other end side end portion of the cylindrical body protruding from the other end side end portion of the elastic body, the adhesive is injected into the cutout portion. It becomes easy to supply the adhesive to the recess, and the workability of the adhesive injection work can be improved.

  According to the damper member connecting structure according to the present invention, a concave portion extending from the other end side to the one end side is provided on the inner surface of the cylindrical body, and the damper is supplied by the adhesive that is supplied to the concave portion and has a low viscosity and cures in a short time. By fixing the member to the operating rod, even if the gap between the fitting portion of the damper member and the operating rod is slightly different, the work machine can maintain the reliability of the adhesive strength that the damper member adheres to the operating rod in a high state. The damper member connecting structure can be provided.

  Hereinafter, a preferred embodiment of a damper member connecting structure according to the present invention will be described with reference to FIGS. This embodiment will be described below using a brush cutter among handheld work machines as an example.

  First, before explaining the damper member connecting structure of the present invention, a brush cutter having this structure will be outlined. As shown in FIG. 1 (perspective view), the brush cutter 1 has a cutting work unit 5 provided with a rotary blade 5a attached to a distal end that is one end side of the operating rod 3, and a base that is the other end side of the operating rod 3. A prime mover 7 such as an engine is disposed at the end, and the power of the prime mover 7 is transmitted to the rotary blade 5a via a power transmission shaft or the like disposed in the operation rod 3. The operating rod 3 is generally made of aluminum.

  As shown in FIG. 2 (side view), the fan cover 8 of the prime mover 7 is integrally formed with a mounting cylinder portion 8a that protrudes toward the distal end side, and a drive shaft 11 is provided at the base end side of the mounting cylinder portion 8a. Is supported rotatably. Further, a damper member 20 is disposed in the mounting cylinder portion 8a so as to abut on and fit to the inner peripheral surface.

  Next, a damper member connecting structure for connecting the operating rod 3 to the mounting cylinder portion 8a by the damper member 20 will be described. The damper member 20 is fixed to the mounting cylinder part 8a by a stopper 13 inserted into the mounting cylinder part 8a, and the stopper 13 is fixed to the mounting cylinder part 8a by a screw 14. As shown in FIG. 3 (perspective view), the damper member 20 includes a cylindrical body 21 and a cylindrical body made of a metal material (lightweight and high-strength aluminum alloy is good) fitted to the proximal end portion of the operation rod 3. And an elastic body 31 made of rubber joined to the outer surface of 21. As shown in FIGS. 4A (cross-sectional view) and (b) (side view), the cylindrical body 21 is evenly arranged in the circumferential direction on the inner surface of the cylindrical body 21 (in FIG. 4, three equal arrangements). ) And three concave portions 22 extending from the proximal end side to the distal end side of the cylindrical body 21. The front ends of these recesses 22 extend to a position before the front end of the cylindrical body 21 (for example, a position 5 mm from the front end to the front). That is, the tip end of the recess 22 does not reach the tip end position of the cylindrical body 21. The concave portion 22 is formed in a substantially semicircular shape in a side view and has a size (for example, a radius of about 0.5 mm) that allows the adhesive to flow. The adhesive has a low viscosity and cures in a short time, and has a high adhesive strength after curing. For example, a cyanoacrylate-based material is preferable.

  The proximal end of the cylindrical body 21 protrudes with a predetermined length from that of the elastic body 31. The protrusion 21 a is provided with a notch 21 b communicating with each recess 22, and the notch 21 b functions as an injection port when an adhesive is injected into each recess 22. The protrusion 21a only needs to have a length L that allows the adhesive to be injected, and the length L is, for example, 3 mm. A through hole 24a that constitutes a part of the insertion hole 24 through which the stopper 13 shown in FIG. 2 is inserted is provided at the end on the distal end side of the cylindrical body 21.

  The elastic body 31 is formed in a cylindrical shape, and a notch groove 32 extending in the circumferential direction is provided in an intermediate portion in the axial direction. A part of the surface of the cylindrical body 21 is exposed through the notch groove 32. The elastic body 31 has an outer diameter that can be brought into contact with the inner surface of the mounting cylinder portion 8a shown in FIG. 2 in an elastically deformed state. A through hole 24b that constitutes a part of the insertion hole 24 that communicates with the through hole 24a is provided at the end of the elastic body 31 on the front end side. That is, the through hole 24a of the cylindrical body 21 and the through hole 24b of the elastic body 31 communicate with each other, and the through holes 24a and 24b that communicate with each other constitute the insertion hole 24 through which the stopper 13 shown in FIG.

  In order to mount the damper member 20 configured in this manner on the proximal end portion of the operating rod 3, the damper member 20 is fitted to the proximal end portion of the operating rod 3 as shown in FIG. The base end side end portion of the damper member 20 and that of the operation rod 3 are aligned so as to be positioned on substantially the same plane. At this time, the insertion hole 24 of the damper member 20 and the through hole 26 provided on the proximal end side of the operating rod 3 are brought into a communication state. Then, the tubular body 21 is caulked via the notch groove 32 to temporarily prevent the damper member 20 from rotating with respect to the operating rod 3. And an adhesive agent is inject | poured into the notch part 21b. When the adhesive is injected into the notch 21b, the adhesive flows in the recess 22 shown in FIG. 4A and moves to the tip side of the damper member 20, and is operated from the recess 22 by the surface tension of the adhesive. It spreads to the base end surface 3a which is a fitting gap between the flange 3 and the cylindrical body 21.

  For this reason, even when the gap of the fitting portion between the damper member 20 and the operating rod 3 is somewhat different within the range of dimensional tolerance (10 to 200 μm in the embodiment), the concave portion 22 performs the function of receiving the adhesive, Since the inner surface of the cylindrical body 21 extends from the other end side to the one end side, the adhesive easily spreads to the base end surface 3a and the variation in the range of the adhesive spreading on the base end surface 3a can be reduced. it can. Accordingly, the reliability of the adhesive strength at which the damper member 20 adheres to the operation rod 3 can be maintained in a high state, and the possibility that the operation rod 3 is peeled off from the damper member 20 during the mowing operation is prevented. can do.

  Further, the tip of the recess 22 does not extend to the tip of the cylindrical body 21. For this reason, an adhesive agent does not leak from the front end side of the cylindrical body 21, and the adhesive agent supplied to the recessed part 22 can be supplied to the base end surface 3a of the operating rod 3 without waste. As a result, the reliability with high adhesive strength between the operating rod 3 and the damper member 20 can be more reliably maintained. Further, since a plurality of the recesses 22 are provided at a predetermined interval in the circumferential direction of the cylindrical body 21, it becomes easier for the adhesive to spread on the base end surface 3 a of the operation rod 3, and the operation rod 3, the damper member 20, High reliability of the adhesive strength can be ensured.

  That is, in the damper member coupling structure of the present invention, the concave portion 22 extending from the base end side to the distal end side is provided on the inner surface of the cylindrical body 21, and the adhesive supplied to the concave portion 22 is received by the concave portion 22 and is operated. 3 is spread and hardened so as to be seen on the base end surface 3a, and the damper member 20 is fixed to the operation rod 3.

  In the above-described embodiment, the concave portion 22 formed in the cylindrical body 21 is shown as an example extending in the axial direction of the damper member 20, but the present invention is not limited to this, and FIG. As shown, the cylindrical body 21 may further be provided with a communication recess 35 that extends in the circumferential direction of the cylindrical body 21 and communicates between the recesses 22 adjacent to each other in the circumferential direction. By providing the communication recess 35 in this manner, the adhesive can be more easily spread to the base end surface 3a of the operation rod 3, and it is further ensured that the operation rod 3 and the damper member 20 are maintained with high adhesive strength and reliability. can do.

  Moreover, in the above-described embodiment, the damper connection structure taking the brush cutter 1 as an example was shown, but by providing the damper trimmer or the like with the damper member connection structure of the present invention, the same effect as in the case of the brush cutter 1 described above, That is, even when the gap between the fitting portions of the operating rod 3 and the damper member 20 is slightly different, it is possible to obtain an effect capable of maintaining high reliability of the adhesive strength between the operating rod 3 and the damper member 20.

The perspective view of the brush cutter which mounts the damper member connection structure concerning one embodiment of this invention is shown. It is a side view which shows the connection state of the attachment cylinder part and operating rod of the motor | power_engine of this brush cutter. The perspective view of the damper member fitted by the base end side edge part of the operating rod is shown. The damper member is shown. FIG. 4A shows a side view of the damper member corresponding to the IV-IV arrow view of FIG. 4B, and FIG. 4B shows a side view of the damper member. Sectional drawing of the damper member for demonstrating the attachment method which attaches a damper member to an operating rod is shown. Sectional drawing of the damper member which provided the communication recessed part in the cylindrical body is shown.

Explanation of symbols

1 Brush cutter (work machine)
3 Operation rod 3a Base end surface (other end surface)
5 Cutting work part (work part)
7 Motor 8a Mounting cylinder part 20 Damper member 21 Cylindrical body 21a Protruding part 22 Recessed part 31 Elastic body 35 Communication recessed part

Claims (5)

A working unit is provided at one end of the operating rod, a prime mover is provided at the other end of the operating rod, and the operating rod is connected to a mounting cylinder portion of the prime mover via a damper member. A damper member coupling structure for a work machine that includes a cylindrical body that is fitted to the other end of the operating rod and an elastic body that is joined to an outer surface of the cylindrical body, and is inserted into the mounting cylinder. ,
On the inner surface of the cylindrical body, a recess extending from the other end side of the cylindrical body to one end side is provided,
A damper member connecting structure for a working machine, wherein the damper member is fixed to the operating rod by an adhesive that is supplied to the recess and has a low viscosity and cures in a short time.   2. The damper member connection structure for a working machine according to claim 1, wherein the concave portion extends from the other end side of the cylindrical body to a position before the one end portion.   The damper member connecting structure for a work machine according to claim 1 or 2, wherein a plurality of the recesses are provided at a predetermined interval in a circumferential direction of the cylindrical body.   4. The damper member connection structure for a working machine according to claim 3, wherein a communication recess is provided on the inner surface of the cylindrical body so as to communicate between the recesses adjacent to each other in the circumferential direction of the cylindrical body.   The other end side end portion of the cylindrical body of the damper member protrudes from the other end side end portion of the elastic body, and a notch portion that communicates with the recess portion is provided in the protruding protrusion portion. Item 5. A damper member connecting structure for a working machine according to any one of Items 1 to 4.

Images