JP6076165B2 - Vibration isolator for portable work machines - Google Patents

Description

  The present invention relates to a vibration isolator provided between two members of a portable work machine such as a back-load type blower device.

  Patent Document 1 discloses a vibration isolator for a hand-held work machine that is a kind of this kind of portable work machine. This vibration isolator is provided with a coil spring between a casing that supports a prime mover of a hand-held work machine and a grip held by a user, and prevents vibration of the prime mover from being transmitted from the grip to the user. One end of the coil spring of the vibration isolator is fixed by being screwed into a female screw formed on the inner peripheral surface of the grip bush, and the other end is fixed by being screwed into a female screw formed on the inner peripheral surface of the through hole of the casing. Has been.

JP 2001-1116074 A

  When disassembling the hand-held working machine of Patent Document 1 for maintenance or repair, it is necessary to remove the grip from the casing. However, since the coil spring is screwed into both the casing and the grip, the work of removing the coil spring from the casing and the grip is not easy, and the work of screwing the coil spring into the casing and the grip again is troublesome. It was. Furthermore, when the hand-held work machine is used for a long period of time, the coil spring may be strongly engaged with the casing and the female thread of the grip, making it more difficult to remove. An object of the present invention is to make it possible to easily separate two members in a vibration isolator provided between a member supporting a prime mover and a member held by an operator.

In order to solve the above-described problems, the present invention provides a vibration isolator provided on two members, a member that supports a prime mover of a portable work machine and a member that is held by an operator. A coil spring that is connected in a vibrational manner, a fixed portion to which one end of the coil spring is fixed by one of the two members, and a through hole that is formed in the fixed portion and communicates from one end of the coil spring to the inside A sleeve fixed to the other end of the coil spring, a boss that protrudes longer than the axial length of the sleeve on the other of the two members and loosely fits on the inner periphery of the sleeve, and a diameter larger than the inner diameter of the sleeve There is provided a vibration isolator for a portable work machine comprising a retaining member that is detachably provided at the tip of the boss portion.

  In the vibration isolator of the portable work machine configured as described above, one end portion of the coil spring that couples the two members in a vibration-proof manner is fixed to the fixing portion of one member, while the other The end portion of the boss portion was fixed to the sleeve fixed to the sleeve, while the boss portion of the other member was loosely fitted to the sleeve. If the retaining member is removed from the tip of the boss using a tool inserted into the coil spring from the through hole of one member, the sleeve fixed to the other end of the coil spring is pulled out from the boss of the other member. The two members can be separated from each other. Also, the boss part of the other member is loosely fitted to the sleeve fixed to the other end part of the coil spring, and the tool is inserted into the coil spring from the through hole of one member to prevent it from coming off at the tip of the boss part. If a member is attached, two members can be easily connected. Further, since the sleeve fixed to the other end of the coil spring is loosely fitted by the retaining member while being loosely fitted to the boss portion that is longer in the axial direction, the sleeve is restricted from rotating with respect to the boss portion. The coil spring is not twisted and attached. Thereby, the coil spring can prevent the spring constant from being changed due to twisting.

It is the perspective view seen from diagonally back of the backpack type blower device which is one embodiment of the portable work machine of the present invention. It is sectional drawing of the vibration isolator of FIG.

  Hereinafter, a vibration isolator for a portable work machine according to the present invention will be described with reference to the accompanying drawings. In the present embodiment, a back blower device will be described as an example of a portable work machine. As shown in FIG. 1, the back blower apparatus 10 includes a blower unit 20 in a back frame 11 carried by a worker. The back frame 11 has an L-shape when viewed from the side consisting of a back abutment portion 11a extending vertically and hitting the operator's back, and a pedestal portion 11b extending rearward from the lower portion of the back abutment portion 11a. A pair of shoulder straps 12, 12 are attached to the backrest portion 11 a of the backpack frame 11 for the operator to carry on his back. A support arm 13 that supports the air duct 24 is fixed to the right side of the backpack frame 11.

  The blower unit 20 ejects air sucked by the rotation of a fan (not shown) driven by a prime mover 21 made of an engine from an ejection duct 23. The blower unit 20 includes a volute case 22 in which a prime mover 21 is integrally assembled. A fan (not shown) is accommodated in the volute case 22. The volute case 22 is integrally provided with an ejection duct 23 that ejects air sucked by a fan, and a blower pipe 24 is connected to the ejection duct 23.

  An anti-vibration device 30 is provided between the back frame (a member held by the operator carrying the back) 11 and a volute case (a member supporting the prime mover 21) 22 that supports the prime mover 21. The vibration isolator 30 has a function of suppressing the vibration generated by the prime mover 21 and the vibration generated by the rotation of the fan from being transmitted to the back frame 11 through the volute case 22. In this embodiment, the vibration isolator 30 includes two portions on the left and right between the upper portion of the backrest portion 11a of the backpack frame 11 and the portion of the volute case 22 facing the backrest portion 11a, and the base of the backpack frame 11. It is provided in two places on the left and right between the front part of the part 11b and the part facing the pedestal part at the front part of the volute case 22.

  Below, the vibration isolator 30 provided between the front left part of the base part 11b of the backpack frame 11 and the front left part of the volute case 22 will be described. The vibration isolator 30 includes a coil spring 31 that connects the back frame 11 and the volute case 22 to each other in a vibration-proof manner. A cylindrical fixing portion 32 is provided at the front left portion of the pedestal portion 11b of the backpack frame 11, and a circular through hole 32a that penetrates to the lower side of the pedestal portion 11b is formed in the fixing portion 32. . A spiral groove 32b is formed on the inner peripheral surface of the through hole 32a of the fixed portion 32, and one end of the coil spring 31 is engaged with the spiral groove 32b. Alternatively, a spiral groove may be formed on the outer peripheral surface of the fixed portion 32, and one end of the coil spring 31 may be engaged with the spiral groove.

  A cylindrical sleeve 33 is provided inside the other end of the coil spring 31, and the other end of the coil spring 31 is engaged with a spiral groove 33 a formed on the outer peripheral surface of the sleeve 33. A boss 34 having a cylindrical shape protruding toward the coil spring 31 is provided at the front left portion of the volute case 22, and the boss 34 is loosely fitted to the sleeve 33 with a slight gap. The boss portion 34 is loosely fitted to the sleeve 33 with a slight gap that does not substantially move between the inner peripheral surface of the sleeve 33. The length of the boss 34 is slightly longer than that of the sleeve 33. A screw hole 34a extending in the axial direction is formed at the center of the boss 34 in the radial direction, and a screw 35 with a washer 36 is detachably screwed into the screw hole 34a. The washer 36 has a larger diameter than the inner diameter of the sleeve 33, and the washer 36 functions as a retaining member that prevents the sleeve 33 from coming off the boss portion 34. In addition, by making the head portion 35a of the screw 35 larger than the diameter of the sleeve 33, the head portion 35a of the screw 35 may function as a member for preventing the sleeve 33 from coming off without using the washer 36. Similarly, the head 35a of the screw 35 may be provided with a flange having a diameter larger than the diameter of the sleeve 33, and the flange may function as a sleeve retaining member. The anti-vibration device provided between the front right portion of the pedestal 11b of the back frame 11 and the front right portion of the volute case 22 is the same as the anti-vibration device 30 described above. Further, the vibration isolator between the back rest portion 11a of the backpack frame 11 and the upper part of the volute case 22 is the same as the above-described vibration isolator 30 except that the fixing portion 32 is provided in the back rest portion 11a.

  The operation of the backpack type blower device 10 configured as described above will be described. When the operator operates the prime mover 21, the fan in the volute case 22 rotates, and the air sucked into the volute case 22 is ejected from the tip of the air duct 24 through the ejection duct 23. At this time, the volute case 22 vibrates due to the operation of the prime mover 21 and the rotation of the fan in the volute case 22, but the vibration of the volute case 22 is suppressed from being transmitted to the back frame 11 by the vibration isolator 30.

  In the vibration isolator 30 of the backpack type blower apparatus 10 configured as described above, one end of the coil spring 31 that connects the backpack frame 11 and the volute case 22 in a vibration-proof manner is a fixed portion of the backpack frame 11. The other end of the coil spring 31 is secured by a washer 36 secured to the tip of the boss 34 with a screw 35 while the boss 34 of the volute case 22 is loosely fitted to a sleeve 33 secured thereto. Has been fixed.

  When removing the volute case 22 from the back frame 11 during maintenance of the back blower device 10, a rod-like tool such as a screwdriver inserted into the coil spring 31 from the through hole 32a of the base portion 11b of the back frame 11 is used. If the screw 35 and the washer 36 are removed from the tip of the boss 34, the sleeve 33 at the other end of the coil spring 31 can be pulled out from the boss 34 of the volute case 22. Also in the other three vibration isolators, if the screw and washer are removed from the tip of the boss portion, the sleeve at the other end of the coil spring can be pulled out from the boss portion of the volute case. In this state, the volute case 22 is removed from the back frame 11 by pulling out the sleeve 33 from the boss portion 34.

  Further, when the volute case 22 is attached to the backpack frame 11, the boss 34 of the volute case 22 is loosely fitted to the sleeve 33 at the other end of the coil spring 31, and the coil is inserted from the through hole 32 a of the pedestal portion 11 b of the backpack frame 11. A screw 35 is attached to the tip of the boss portion 34 together with a washer 36 using a rod-like tool such as a screwdriver inserted into the spring 31. As a result, the sleeve 33 at the other end of the coil spring 31 cannot be removed from the boss portion 34 by the washer 36, and the volute case 22 is attached to the backpack frame 11.

  As described above, in the vibration isolator 30 according to the present embodiment, the sleeve 33 at the other end of the coil spring 31 is fixed to the boss 34 by simply attaching and detaching the washer 36 to the tip of the boss 34 with the screw 35. In this state, the sleeve 33 is removable from the boss portion 34. Thereby, when the maintenance of the back blower type blower device 10 is performed, the back frame 11 and the volute case 22 by the vibration isolator 30 can be obtained simply by attaching and detaching the washer 36 to the tip of the boss part 34 loosely fitted to the sleeve 33 by the screw 35. The connection to and release from the connection can be made, and the work of attaching and detaching the volute case 22 to the backpack frame 11 becomes easy. Further, since the boss portion 34 is loosely fitted to the sleeve 33 with a slight gap, the boss portion 34 is firmly fitted to the sleeve 33 even when the back-load type blower device 10 is used for a long time. The boss portion 34 may not be attached to and detached from the sleeve 33 with a strong force.

  Further, the sleeve 33 at the other end of the coil spring 31 is retained by a washer 36 while being loosely fitted to a boss 34 that is longer in the axial direction. For this reason, the rotation of the sleeve 33 with respect to the boss portion 34 is not restricted, and the coil spring 31 is not twisted and attached. Thereby, the coil spring 31 can prevent the spring constant from being changed due to twisting.

  In the above embodiment, one of the two members is the back frame 11 and the other is the volute case 22, but the present invention is not limited to this, and one of the two members is the volute case 22 and the other is the other. Even if the back frame 11 is used, the same effect can be obtained.

  In the above embodiment, the vibration isolator 30 includes the left and right two places between the upper portion of the backrest portion 11a of the backpack frame 11 and the upper portion of the volute case 22 and the portion facing the backrest portion 11a. However, the present invention is not limited to this. For example, the vibration isolator 30 is provided in two places between the front part of the pedestal part 11b and the front part of the volute case 22 between the part facing the pedestal part. May be provided at the left and right two places on the upper portion of the backrest portion 11a of the back frame 11 and the two left and right portions on the lower portion, and the left and right two places on the upper and lower portions of the volute case 22 facing them. Good.

  Moreover, in said embodiment, although demonstrated using backpack type blower apparatus 10 as one Embodiment of a portable work machine, this invention is not restricted to this, The member and operator who supported the motor | power_engine are As a portable working machine provided with a member to be held, it can also be adopted in portable working machines such as a hand-held blower device, a chain saw, and a hedge trimmer. The prime mover is not limited to the engine, and may be an electric motor. Furthermore, the member held by the worker is not limited to the backpack frame held by the worker, but may be a grip or a handle held by the worker.

DESCRIPTION OF SYMBOLS 10 ... Portable working machine (backpack type blower device), 11 ... Member held by worker (backpack frame), 21 ... Motor, 22 ... Member (volute case) supporting motor, 30 ... Vibration isolator, 31 ... Coil spring, 32... Fixing part, 32a .. through hole, 33 .. sleeve, 34 .. boss part, 36 .. retaining member (washer).

Claims (1)

A vibration isolator provided between two members, a member supporting a prime mover of a portable work machine and a member held by an operator,
A coil spring that couples the two members together in a vibration-proof manner;
A fixing portion having a through hole formed in one of the two members, and having one end portion of the coil spring fixed to a peripheral portion of the through hole;
A sleeve fixed to the other end of the coil spring;
A boss that protrudes longer than the length of the sleeve in the axial direction on the other of the two members and loosely fits on the inner periphery of the sleeve;
An anti-vibration device for a portable work machine, comprising: a retaining member having a diameter larger than an inner diameter of the sleeve and detachably provided at a tip of the boss portion.

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