Walk-behind work machine

Abstract

To provide a walking type work machine capable of restraining that gear shifting operation for a gear shift operation tool is operated to shift to a prescribed gear stage in association with rotation of a handle.SOLUTION: A walking type work machine comprises: a gear shift operation tool 41 capable of performing gear shift operation; a handle 30 rotatable between a first work position (positive handle position) and a second work position (reverse handle position) inverted from the first work position; a rotating component 51 which can rotate integrally with the handle 30; and a restraint part 52 that is so located as to contact the rotating component 51, and restrains gear shifting operation for the gear shift operation tool 41 to a prescribed gear stage by displacing a rotation axial direction of the rotating component 51 according to rotation of the rotating component 51.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a technology for a walk-behind working machine in which the direction of a handle can be reversed. [Background technology]

[0002] Conventionally, technology for a walk-behind working machine that allows the direction of the handle to be reversed is well known, as described in Patent Document 1, for example.

[0003] Patent Document 1 discloses a walk-behind working machine equipped with a handle that can be rotated between a forward handle position and a reverse handle position. In the technology described in Patent Document 1, when the handle is supported in the reverse handle position, gear shifting is restricted so that only a low speed can be selected as the speed at which the walk-behind working machine travels in a direction approaching the worker.

[0004] Specifically, the walk-behind working machine described in Patent Document 1 is equipped with a travel speed change restricting member for restricting (restricting) gear shifting. The worker moves the travel speed change restricting member in a predetermined direction according to the position of the handle. This travel speed change restricting member restricts the movement of the operating tool for gear shifting, making it impossible to change gear to a high speed.

[0005] However, the technology described in Patent Document 1 requires the operator to operate the travel speed change restricting member according to the position of the handle, which makes operation of the walk-behind working machine complicated and leaves room for improvement. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-147145 Summary of the Invention [Problem to be solved by the invention]

[0007] One aspect of the present disclosure has been made in consideration of the above-described circumstances, and the problem it aims to solve is to provide a walk-behind working machine that can prevent a speed change operating device from being operated to a predetermined gear stage as the handle is turned. [Means for solving the problem]

[0008] The problem to be solved by one embodiment of the present disclosure has been described above, and next, the means for solving this problem will be described.

[0009] A walk-behind working machine according to one aspect of the present disclosure includes a speed change device capable of speed change operation, a handle rotatable between a first working position and a second working position inverted from the first working position, a rotating member rotatable integrally with the handle, and a lever arranged to contact the rotating member and adapted to rotate in response to the rotation of the rotating member. In conjunction and a check portion that checks the speed change operation of the speed change operating device to a predetermined speed by displacing the rotating member in the direction of the rotation axis. According to one aspect of the present disclosure, it is possible to prevent the gear shifting device from being operated to a predetermined gear position in response to rotation of the handle.

[0010] Furthermore, according to one aspect of the present disclosure, a guide surface that guides the check portion is formed on an end surface of the rotating member in the direction of the rotation axis, and the guide surface moves in the circumferential direction of the rotating member. In the direction of the rotation axis It has a sloped portion that changes position. According to one aspect of the present disclosure, a gear shift operation can be inhibited with a simple configuration.

[0011] Furthermore, the guide surface according to one aspect of the present disclosure is formed on an upper end surface of the rotating member. According to one aspect of the present disclosure, a gear shift operation can be inhibited with a simple configuration.

[0012] Furthermore, the walk-behind working machine according to one aspect of the present disclosure further includes a downward biasing member that biases the check portion downward. According to one aspect of the present disclosure, the check section can be operated smoothly.

[0013] Furthermore, the guide surface according to one aspect of the present disclosure is formed on a lower end surface of the rotating member. According to one aspect of the present disclosure, a gear shift operation can be inhibited with a simple configuration.

[0014] Moreover, the walk-behind working machine according to one aspect of the present disclosure further includes an upward biasing member that biases the check portion upward. According to one aspect of the present disclosure, the check section can be operated smoothly.

[0015] Furthermore, the rotating member according to one aspect of the present disclosure includes a first rotating member and a second rotating member arranged on one side of the first rotating member in the direction of the rotation axis, and guide surfaces for guiding the check portion are formed on the opposing end faces of the first rotating member and the second rotating member. According to one aspect of the present disclosure, a gear shift operation can be inhibited with a simple configuration.

[0016] Furthermore, in one aspect of the present disclosure, a guide groove for guiding the check portion is formed on a side surface of the rotating member in the direction of the rotation axis. According to one aspect of the present disclosure, a gear shift operation can be inhibited with a simple configuration. [Effects of the Invention]

[0017] According to one aspect of the present disclosure, it is possible to prevent the gear shifting device from being operated to a predetermined gear position in response to rotation of the handle. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a side view showing the overall configuration of a walk-behind working machine according to one embodiment of the present disclosure. [Figure 2] Also, plan view. [Figure 3]FIG. 2 is a perspective view showing a handle support base, a handle, a gear shift operation mechanism, and a check mechanism according to the first embodiment. [Figure 4] FIG. 5 is an exploded perspective view showing the state in which the parts of FIG. 4 are disassembled. [Figure 5] FIG. 2 is a front view showing the handle support base, the gear shift operation mechanism, and the check mechanism. [Figure 6] FIG. [Figure 7] (a) is a plan view showing the rotating member, and (b) is a side view of the same. [Figure 8] 1A is a plan view showing the positional relationship between the rotating member and the contact portion at the normal handle position, and FIG. [Figure 9] 1A is a plan view showing the positional relationship between the rotating member and the contact portion in the reverse handle position, and FIG. [Figure 10] (a) Front view showing the check plate in the lowered position. (b) Front view showing the check plate in the raised position. [Figure 11] 1A is a schematic diagram showing the rotating members and the like in the reverse handle position in an example provided with a downward biasing member, and FIG. 1B is a schematic diagram showing the rotating members and the like in the normal handle position in the example provided with a downward biasing member. [Figure 12] 10A is a schematic diagram showing the rotating members and the like at the reverse handle position in a modified example of the first embodiment, and FIG. 10B is a schematic diagram showing the rotating members and the like at the normal handle position in the modified example of the first embodiment. [Figure 13] FIG. 10 is an exploded perspective view showing a handle support base, a handle, a gear shift operation mechanism, and a check mechanism according to a second embodiment. [Figure 14] FIG. 2 is a front view showing the handle support base, the gear shift operation mechanism, and the check mechanism. [Figure 15] 1A is a front view showing a guide surface formed on the inner cylindrical portion, FIG. 1B is a side view of the same, and FIG. 1C is a bottom view of the same. [Figure 16] (a) A schematic diagram showing the positional relationship between the guide surface and the contact portion when the handle is in the forward position. (b) A schematic diagram showing the positional relationship between the guide surface and the contact portion when the handle is in the reverse position. [Figure 17] 10A is a schematic diagram showing the positional relationship between the guide groove and the abutment portion at the forward handle position in a modified example of the second embodiment, and FIG. 10B is a schematic diagram showing the positional relationship between the guide groove and the abutment portion at the reverse handle position. [Figure 18] FIG. 11 is a perspective view showing a handle support base, a handle, a gear shift operation mechanism, and a check mechanism according to a third embodiment. [Figure 19] FIG. 5 is an exploded perspective view showing the guide plate and the handle of FIG. 4 in an exploded state. [Figure 20] FIG. 2 is a front view showing the handle support base, the gear shift operation mechanism, and the check mechanism. [Figure 21] FIG. [Figure 22] FIG. 10 is a plan view showing the rotating member, the check portion, and the guide plate in the normal handle position. [Figure 23] FIG. 10 is a plan view showing the rotating member, the check portion, and the guide plate in the reverse handle position. [Figure 24] FIG. 10 is an exploded perspective view showing a handle support base, a handle, a gear shift operation mechanism, and a check mechanism according to a fourth embodiment. [Figure 25] FIG. 2 is a front view showing the handle support base, the gear shift operation mechanism, and the check mechanism. [Figure 26] FIG. 10 is a plan view showing the rotating member and the guide plate in the normal handle position. [Figure 27] FIG. 10 is a plan view showing the rotating member and the guide plate in the reverse handle position. DETAILED DESCRIPTION OF THE INVENTION

[0019] In the following description, the directions indicated by arrows U, D, F, B, L, and R in the figures are defined as upward, downward, forward, backward, leftward, and rightward, respectively.

[0020] The overall configuration of a walk-behind working machine 1 according to a first embodiment of the present invention will be described below with reference to FIGS.

[0021] The walk-behind working machine 1 mainly comprises a transmission case 2, wheels 3, an engine support frame 4, an engine 5, a fuel tank 6, a belt cover 8, a handle support base 20, a handle 30, a speed change operation mechanism 40, and a check mechanism 50.

[0022] The transmission case 2 houses a transmission mechanism capable of changing gears (multiple forward and backward stages). A pair of wheels 3 are mounted on the left and right sides of the transmission case 2 via axles. An engine support frame 4 is fixed to the front of the transmission case 2. An engine 5 and a fuel tank 6 are mounted on the engine support frame 4. A cylindrical fuel filler port 6a is formed on the top surface of the fuel tank 6 for filling with fuel.

[0023] A belt cover 8 is provided on the left side of the engine 5 and the transmission case 2. A transmission mechanism (not shown) for transmitting the power of the engine 5 to the transmission case 2 is housed inside the belt cover 8. The transmission mechanism is provided with a main clutch that switches between transmitting and not transmitting power.

[0024] A handle support base 20 is provided on the upper part of the transmission case 2. A handle 30 is rotatably mounted on the handle support base 20. The handle 30 can be rotated about an axis in a substantially vertical direction. This allows the rotation position of the handle 30 to be switched between a normal handle position (position indicated by a solid line in FIG. 1) in which the handle 30 faces rearward, and a reverse handle position (position indicated by a two-dot chain line in FIG. 1) in which the handle 30 is inverted from the normal handle position and faces forward.

[0025] When the handle 30 is set to the normal handle position, the worker stands behind the walk-behind working machine 1 and performs various tasks while operating the walk-behind working machine 1 (for convenience, hereinafter, work in this state will be referred to as "normal position work"). When the handle 30 is set to the reverse handle position, the worker stands in front of the walk-behind working machine 1 and performs various tasks while operating the walk-behind working machine 1 (for convenience, hereinafter, work in this state will be referred to as "reverse position work").

[0026] A gear change operation mechanism 40 for changing the gear position of the transmission mechanism is provided on the left side of the handlebars 30. Gear change operations using the gear change operation mechanism 40 are appropriately restricted by a restricting mechanism 50 (see Figure 4, etc.), which will be described later.

[0027] Next, the configuration for restraining gear shifting operations by the gear shifting operation mechanism 40 (specifically, the handle support base 20, handle 30, gear shifting operation mechanism 40, and restraining mechanism 50 shown in Figures 2 and 3, etc.) will be described in detail.

[0028] 3 and 4 rotatably supports the handle 30. The handle support base 20 mainly includes a support base main body 21 and a fulcrum shaft 22.

[0029] 4 and 5 is a part that forms the main structure of the handle support base 20. The support base main body 21 is formed in a roughly U-shape when viewed from the front, having an upper surface and a pair of side surfaces extending downward from both ends of the upper surface. A slit 21a extending vertically from the upper end to the lower end of the left side surface is formed in the left side surface of the support base main body 21.

[0030] The fulcrum shaft 22 is a part that serves as a rotation fulcrum for the handle 30, rotating member 51, etc., which will be described later. The fulcrum shaft 22 is formed in a substantially cylindrical shape. The fulcrum shaft 22 is arranged with its axis (the rotation axis of the handle 30, etc., which will be described later) facing in the vertical direction. The fulcrum shaft 22 is fixed to approximately the center of the upper surface of the support base main body 21. The fulcrum shaft 22 is arranged so as to protrude upward from the upper surface of the support base main body 21.

[0031] 1 to 3 is a part that an operator grips when operating the walk-behind working machine 1. The handle 30 mainly comprises a handle body 31, a handle base 32, and a rotational connecting portion 33.

[0032] 1 and 2 is the portion that forms the tip side of the handle 30. The handle body 31 is provided with a grip that can be held by an operator, various operating tools, etc. The handle body 31 is fixed to a handle base 32, which will be described later.

[0033] 1 to 3 is a portion that forms the base end side of the handle 30. The handle base 32 is formed in the shape of a hollow box made up of a combination of multiple plate-like members.

[0034] The pivotal connecting portion 33 shown in Figures 3 and 4 is a portion that is connected to the handle support base 20. The pivotal connecting portion 33 has two cylindrical members (an outer cylindrical portion 33a and an inner cylindrical portion 33b) that are arranged in a double configuration. The inner cylindrical portion 33b is arranged inside the outer cylindrical portion 33a. An appropriate gap is formed between the outer cylindrical portion 33a and the inner cylindrical portion 33b. The outer cylindrical portion 33a and the inner cylindrical portion 33b are arranged with their axes facing in the vertical direction.

[0035] The fulcrum shaft 22 of the handle support base 20 is inserted into the inside of the outer cylindrical portion 33a (outside the inner cylindrical portion 33b) so as to be relatively rotatable. The fulcrum shaft 22 is inserted into the inner cylindrical portion 33b. This allows the handle 30 to rotate around the axis of the fulcrum shaft 22.

[0036] 1 to 3 is used to change (shift) the gear position of the transmission mechanism housed in the transmission case 2. The gear change operation mechanism 40 is disposed on the left side of the rotational connecting portion 33 of the handle 30. The gear change operation mechanism 40 mainly comprises a gear change operating tool 41, a link mechanism 42, a guide rod 43, and a guide plate 44.

[0037] The speed change operating device 41 is used to perform speed changes. The speed change operating device 41 is formed in an elongated shape. One end (tip end) of the speed change operating device 41 is provided with a grip for the operator to hold. The other end (base end) of the speed change operating device 41 is connected to a link mechanism 42, which will be described later.

[0038] 3 and 4 is for switching the gear position of the speed change mechanism in response to the operation of the speed change operating device 41. The link mechanism 42 mainly includes a boss portion 42a and a link portion 42b.

[0039] The boss portion 42a is the portion to which the gearshift operating device 41 is connected. The boss portion 42a is formed in a substantially cylindrical shape. The axis of the boss portion 42a is oriented substantially in the vertical direction. One end of the gearshift operating device 41 is inserted into the boss portion 42a.

[0040] The link portion 42b is used to change the gear position of the transmission mechanism. The link portion 42b is fixed to the lower portion of the boss portion 42a. The link portion 42b is connected to the sub-transmission mechanism housed in the transmission case 2 via an appropriate link mechanism (not shown). When the transmission operating device 41 is operated, the gear position of the transmission mechanism is changed via the link portion 42b.

[0041] The guide rod 43, together with a guide plate 44 (described later), guides the operating direction of the gear shift operating device 41. The guide rod 43 is formed of a substantially cylindrical member. The rear portion of the guide rod 43 is fixed to the boss portion 42a. The front portion of the guide rod 43 is positioned so as to protrude forward from the boss portion 42a.

[0042] The guide plate 44 guides the guide rod 43. The guide plate 44 is formed from a plate-shaped member. The guide plate 44 is arranged with its plate surface facing forward and backward. The guide plate 44 is fixed to the left side surface of the support base main body 21. The guide plate 44 is arranged so as to protrude leftward from the slit 21a of the support base main body 21. A guide groove G is formed in the guide plate 44.

[0043] The guide groove G shown in FIG. 6 is for guiding the guide rod 43. The guide groove G is formed so as to penetrate the guide plate 44 from front to back. The guide groove G is formed in a shape (longitudinal shape) that extends long in the up-down direction as a whole. The shape of the guide groove G will be explained in more detail below. The guide groove G mainly comprises a vertical groove GV and a plurality of horizontal grooves GS.

[0044] The longitudinal groove GV is a linear portion extending long in the up-down direction. The lateral groove GS is a linear portion extending long in the left-right direction. The length of the lateral groove GS is formed to be shorter than the length of the longitudinal groove GV. The multiple lateral grooves GS are formed to be aligned at approximately equal intervals from the upper end to the lower end of the longitudinal groove GV. In this embodiment, four lateral grooves GS are formed. The multiple lateral grooves GS are formed to extend left and right from the longitudinal groove GV.

[0045] As shown in Figure 4, guide rod 43 is inserted into guide groove G of guide plate 44. As a result, the guide groove G restricts the direction in which guide rod 43 can move, and guides guided rod 43 to move along the shape of guide groove G. In other words, the gear shift operation (operation direction) by gear shift operating device 41 is guided by guide groove G.

[0046] Furthermore, guide groove G is formed to have a shape corresponding to each gear position of the walk-behind working machine 1. Specifically, when the transmission mechanism is switched to one of the gear positions (forward first gear, forward second gear, ..., reverse first gear, reverse second gear, ..., etc.), guide rod 43 is set to be located at either the left or right end of the multiple lateral grooves GS (shift positions P1 to P8 shown in FIG. 6). The correspondence between the gear positions of the transmission mechanism and the shift positions P in guide groove G is not particularly limited, and can be set arbitrarily depending on the configuration of the transmission mechanism, etc.

[0047] Here, because a common transmission mechanism is used when the handle 30 is pointed to the forward handle position and when the handle 30 is pointed to the reverse handle position, even if the transmission mechanism is shifted to the same gear, the direction of travel of the walk behind work machine 1 relative to the operator will be reversed. For example, the gear corresponding to the "maximum forward speed" when the handle 30 is pointed to the forward handle position becomes the gear corresponding to the "maximum reverse speed" when the handle 30 is pointed to the reverse handle position.

[0048] As described above, since the gears of the transmission mechanism are reversed forward and backward depending on the position of the handlebars 30 (forward handlebar position and reverse handlebar position), it may be preferable to restrict the operation of shifting to a predetermined gear depending on the position of the handlebars 30. For example, since a high-speed gear in the reverse direction is unlikely to be used for work, it is preferable to restrict the operation of shifting to that gear in advance. Therefore, in this embodiment, the operation of shifting to the predetermined gear is restricted by the check mechanism 50, which will be described later.

[0049] 4 and 5 serves to restrict (limit) the shift operation to a predetermined gear position by the shift operating device 41. The restriction mechanism 50 mainly comprises a rotating member 51 and a restriction portion 52.

[0050] The rotating member 51 shown in Figures 4, 5, and 7 is used to move the check mechanism 52 (described later) in accordance with the position of the handle 30. The rotating member 51 is formed in a flat plate shape with its plate surface facing up and down. The rotating member 51 is formed in a roughly fan shape with a circular outer periphery cut out in a plan view (the rear portion in Figure 7). The rotating member 51 is fixed to the lower end of the inner cylindrical portion 33b of the handle 30 inside the support base main body 21 (below the upper surface). This allows the rotating member 51 to rotate integrally with the handle 30. The upper surface (upper end surface) of the rotating member 51 can guide the check mechanism 52 (described later) so that it moves up and down. Hereinafter, the upper surface of the rotating member 51 will be referred to as the guide surface 51a.

[0051] A downwardly inclined portion 51b is formed on a portion of the guide surface 51a (a portion facing the notch in the circumferential direction). The inclined portion 51b is formed by bending a portion of the rotating member 51 downward.

[0052] 4 and 5 blocks the guide groove G of the guide plate 44, thereby preventing the gear shift operation of the gear shift operating device 41 to a predetermined gear position. The check portion 52 mainly includes a check plate 52a and an abutment portion 52b.

[0053] The check plate 52a is a portion that closes the guide groove G of the guide plate 44. The check plate 52a is formed from a plate-shaped member. The check plate 52a is arranged with its plate surface facing forward and backward. The check plate 52a is arranged so that it protrudes to the left from the slit 21a of the support base main body 21. The check plate 52a is arranged so that it can move up and down along the slit 21a. The check plate 52a is formed in a roughly U-shape that opens upward when viewed from the front. The left-right distance between the sides of the check plate 52a is formed so that it is roughly the same as the left-right width of the guide groove G of the guide plate 44.

[0054] A plurality of protrusions 52c that protrude inward in the left-right direction are formed on both left and right side portions of the check plate 52a. The protrusions 52c are formed at positions that correspond to the shape of the guide groove G of the guide plate 44 (positions that correspond to the gear position to be checked). In this embodiment, the check plate 52a is formed with two protrusions 52c on each side. The left protrusion 52c is formed at a lower position than the right protrusion 52c.

[0055] The abutment portion 52b is a portion that can abut against the guide surface 51a of the rotating member 51. The abutment portion 52b is formed in a substantially cylindrical shape. The abutment portion 52b is arranged with its axis oriented in the left-right direction. The left end of the abutment portion 52b is fixed to the front surface of the check plate 52a. As a result, the abutment portion 52b is arranged to protrude to the right from the check plate 52a. The abutment portion 52b is arranged to extend toward the inside of the support base main body 21 through the slit 21a of the support base main body 21. The downward movement of the abutment portion 52b is restricted by a step portion 21b (see Figure 8(b)) formed in the slit 21a.

[0056] The following describes how the speed change operation of the speed change operating device 41 is restricted in the walk-behind working machine 1 configured as described above.

[0057] First, the state in which the handle 30 is switched to the normal handle position will be described.

[0058] 8, when the handle 30 is switched to the normal handle position, the contact portion 52b is separated from the guide surface 51a of the rotating member 51. In this state, the contact portion 52b has descended by its own weight to a position where it contacts the stepped portion 21b.

[0059] In this state, as shown in FIG. 10(a), the check plate 52a is lowered relative to the guide plate 44. Specifically, the check plate 52a is lowered to a position where the two left-side protrusions 52c block shift positions P6 and P8 from the front, respectively. At this time, the two right-side protrusions 52c are positioned so as not to block shift positions P1 to P8. This prevents the guide rod 43 of the gear shift operation mechanism 40 from moving to shift positions P6 and P8, thereby inhibiting gear shift operations to the gears corresponding to those gear positions. For example, if gears that move at high speed in the reverse direction (gears that are not expected to be used with the handlebars in the normal position) are set as gears corresponding to shift positions P6 and P8, operability can be improved by inhibiting gear shift operations to those gears in advance.

[0060] Next, the manner in which the handle 30 is switched to the reverse handle position will be described.

[0061] When the handle 30 is switched from the forward handle position to the reverse handle position, the handle 30 is rotated counterclockwise in a plan view about the fulcrum shaft 22. When the handle 30 rotates, the rotating member 51 rotates integrally with the handle 30.

[0062] When the rotating member 51 rotates, the inclined portion 51b of the rotating member 51 moves relatively closer to the abutting portion 52b. When the rotating member 51 rotates further, the abutting portion 52b rises so as to ride onto the rotating member 51 (guide surface 51a) via the inclined portion 51b, as shown in Fig. 9. That is, the abutting portion 52b is displaced in the direction of the rotation axis of the rotating member 51 in response to the rotation of the rotating member 51.

[0063] Next, a state in which the handle 30 is switched to the reverse handle position will be described.

[0064] When the handlebars 30 are switched to the reverse handlebar position, as shown in Fig. 9, the contact portion 52b is held in a state in which it is placed on the guide surface 51a. In this state, as shown in Fig. 10(b), the check plate 52a is raised relative to the guide plate 44. Specifically, the check plate 52a is lowered to positions where the two protrusions 52c on the right side block shift positions P1 and P3 from the front. At this time, the two protrusions 52c on the left side are positioned so as not to block shift positions P1 to P8. As a result, the guide rod 43 of the gear shift operation mechanism 40 cannot move to shift position P1 or P3, and therefore, gear shifting to the gear corresponding to those shift positions is inhibited. For example, if a gear that moves at high speed in the reverse direction (a gear that is not expected to be used in the reverse handle position) is set as the gear corresponding to gear position P1 and gear position P3, workability can be improved by preventing the gear change operation to that gear in advance.

[0065] Conversely to the above, when the handlebars 30 are switched from the reverse handlebar position (see FIG. 9) to the normal handlebar position (see FIG. 8), the check mechanism 52 descends under its own weight and again blocks the shift positions P6 and P8 from the front (see FIG. 10(a)). In this way, the check mechanism 50 can automatically check the gear shift operation to a predetermined gear by the gear change operating device 41 as the handlebars 30 are turned.

[0066] As described above, the walk-behind working machine 1 according to the first embodiment has the following features: a speed change operation device 41 capable of speed change operation; a handle 30 that is rotatable between a first working position (normal handle position) and a second working position (reverse handle position) that is inverted from the first working position; A rotating member 51 that can rotate integrally with the handle 30; a restraining portion (52) that is disposed so as to come into contact with the rotating member (51) and that restrains the speed change operation of the speed change operating device (41) to a predetermined speed by being displaced in the direction of the rotation axis of the rotating member (51) in response to the rotation of the rotating member (51); It is equipped with the following. With this configuration, it is possible to prevent the gear shift operating device 41 from being operated to a predetermined gear position in response to the rotation of the handle 30. This improves workability. Furthermore, the above configuration simplifies the mechanism for preventing this.

[0067] Further, a guide surface 51a for guiding the check portion 52 is formed on the end surface (upper surface) of the rotating member 51 in the direction of the rotation axis. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0068] Moreover, the guide surface 51a is It is formed on the upper end surface of the rotating member 51. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0069] Although the present embodiment shows an example in which the check portion 52 descends under its own weight, it is also possible to configure the check portion 52 to be urged downward using a biasing member (for example, a compression coil spring, a tension coil spring, a leaf spring, or the like). FIG. 11 shows an example in which the check portion 52 (contact portion 52b) is urged downward using a downward biasing member 53 formed by a compression coil spring. As a result, when the handle 30 is switched from the reverse handle position (see FIG. 11(a)) to the normal handle position (see FIG. 11(b)), the biasing force of the downward biasing member 53 can be used to lower the check portion 52, allowing the check portion 52 to operate smoothly.

[0070] In this way, the walk-behind working machine 1 can further be provided with a downward biasing member 53 that biases the check portion 52 downward. By configuring in this way, the check section 52 can be operated smoothly.

[0071] Next, a modified example of the first embodiment will be described with reference to FIG.

[0072] This modified example differs from the first embodiment in that in addition to the rotating member 51, an upper rotating member 54 that can rotate integrally with the rotating member 51 is provided.

[0073] The upper rotating member 54 is disposed above the rotating member 51. The upper rotating member 54 is formed in substantially the same shape as the rotating member 51. That is, the upper rotating member 54 is formed in a generally fan-like shape in plan view, similar to the rotating member 51 (see FIG. 7, etc.). The upper rotating member 54 is disposed with a gap between it and the rotating member 51 that is large enough to allow the abutment portion 52b of the check portion 52 to pass through. The upper rotating member 54 is fixed to the inner cylindrical portion 33b of the handle 30 together with the rotating member 51. This allows the rotating member 51 and the upper rotating member 54 to rotate integrally with the handle 30. The bottom surface (lower end surface) of the upper rotating member 54 can guide the check portion 52 to move up and down. Hereinafter, the bottom surface of the upper rotating member 54 will be referred to as the guide surface 54a.

[0074] A downwardly inclined portion 54b is formed in a portion of the guide surface 54a (a portion facing the inclined portion 51b of the rotating member 51). The inclined portion 54b is formed by bending a portion of the upper rotating member 54 downward.

[0075] In this modified example, when the handle 30 is rotated from the forward handle position to the reverse handle position, the rotating member 51 and the upper rotating member 54 rotate integrally with the handle 30. When the rotating member 51 and the upper rotating member 54 rotate, the abutting portion 52b rises so as to ride onto the rotating member 51 (guide surface 51a) via the inclined portion 51b, as shown in Figure 12(a). In other words, the abutting portion 52b is displaced in the direction of the rotation axis of the rotating member 51 in response to the rotation of the rotating member 51 and the upper rotating member 54.

[0076] Furthermore, when the handle 30 is rotated from the reverse handle position to the normal handle position, the abutment portion 52b is pushed down by the inclined portion 54b, as shown in Figure 12(b). Thus, in this modified example, the check portion 52 is guided down by the guide surface 54a (inclined portion 54b) of the upper rotating member 54.

[0077] As described above, the rotating member according to this modified example has the following features: A rotating member 51 (first rotating member), an upper rotating member 54 (second rotating member) disposed on one side (upper side) of the rotating member 51 in the direction of the rotation axis; Including, Guide surfaces (guide surface 51a and guide surface 54a) for guiding the check portion 52 are formed on the opposing end surfaces of the rotating member 51 and the upper rotating member 54. With this configuration, the gear shift operation can be inhibited with a simple configuration. Also, the pair of rotating members (rotating member 51 and upper rotating member 54) allows the inhibiting portion 52 to operate smoothly.

[0078] Although the first embodiment has been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention described in the claims.

[0079] For example, in the first embodiment, an example (see FIG. 9, etc.) has been shown in which the rotating member 51 (see FIG. 9, etc.) operates to push up the check portion 52, but it is also possible to operate the check portion 52 so as to push down, for example, using the bottom surface of the rotating member 51. In this case, it is also possible to configure the check portion 52 to return to its initial position (the position before it was pushed down by the rotating member 51) by urging the check portion 52 upward using a biasing member (various types of springs, etc.).

[0080] In addition, in the first embodiment, an example is shown in which the check section 52 descends when the handle 30 is switched to the forward handle position and rises when the handle 30 is switched to the reverse handle position (see Figure 10, etc.), but the relationship between the rotation of the handle 30 and the operating direction of the check section 52 is not limited to this and can be changed as desired.

[0081] The following describes a check mechanism 150 and other components according to a second embodiment of the present invention (see FIGS. 13 to 16). The second embodiment will be described mainly focusing on differences from the first embodiment, and components that are generally similar to those in the first embodiment will be assigned the same reference numerals and will not be described again.

[0082] The second embodiment differs from the check mechanism 50 according to the first embodiment mainly in the configuration of the check mechanism 150. The check mechanism 150 according to the second embodiment mainly includes a check portion 152, a support portion 155, and an upper biasing member 156.

[0083] The check portion 152 shown in FIGS. 13 and 14 mainly comprises a check plate 52a and a contact portion 152b.

[0084] The check plate 52a is formed in substantially the same manner as in the first embodiment (see FIG. 4, etc.). The abutment portion 152b is formed by bending a substantially cylindrical member into a substantially L-shape when viewed from the front. The abutment portion 152b is fixed to the front side surface of the check plate 52a inside the support base main body 21. One end of the abutment portion 152b protrudes downward from the check plate 52a, and the other end of the abutment portion 152b is positioned so as to protrude to the right from the check plate 52a. The other end (right end) of the abutment portion 152b is positioned so as to be located below the bottom surface (guide surface 33c, described later) of the inner cylindrical portion 33b of the handle 30.

[0085] The support part 155 is a member that supports the check part 152. The support part 155 is fixed to the inner surface of the support base main body 21. The support part 155 is provided with a cylindrical part whose axis direction is oriented in the vertical direction, and the lower end part of the abutment part 152b is inserted into the cylindrical part so as to be movable up and down.

[0086] The upward biasing member 156 biases the check portion 152 upward. Any suitable biasing member (e.g., a compression coil spring, a tension coil spring, a leaf spring, etc.) can be used as the upward biasing member 156. The illustration shows the upward biasing member 156 configured as a compression coil spring. The upper biasing member 156 is disposed above the support portion 155, with the upper end of the contact portion 152b inserted therethrough. The upper end of the upper biasing member 156 engages with the contact portion 152b, and the lower end of the upper biasing member 156 abuts against the upper surface of the support portion 155. This allows the upper biasing member 156 to urge the abutment portion 152b upward relative to the support portion 155. The abutment portion 152b, biased upward, abuts against the bottom surface (a guide surface 33c, described later) of the inner cylindrical portion 33b of the handle 30 from below.

[0087] In the second embodiment, instead of the rotating member 51 (guide surface 51a) of the first embodiment, the lower end surface of the inner cylindrical portion 33b of the handle 30 serves as a guide surface 33c that guides the abutment portion 152b.

[0088] As shown in Fig. 15, an upwardly recessed recess 33d is formed in the circumferential midpoint of the guide surface 33c. One end of the recess 33d (the rear end in Fig. 15(b)) forms an inclined surface that slopes toward the lower end surface of the inner cylindrical portion 33b.

[0089] In the second embodiment configured as described above, when the handle 30 is switched to the normal handle position, the contact portion 152b contacts from below the guide surface 33c of the inner cylindrical portion 33b, except for the recessed portion 33d, as shown in Fig. 16(a). In this state, the check plate 52a descends relative to the guide plate 44, as shown in Fig. 10(a).

[0090] When the handlebar 30 is rotated from the forward handlebar position to the reverse handlebar position, the abutment portion 152b moves relative to the inner cylindrical portion 33b to a position facing the recessed portion 33d, as shown in FIG. 16(b). At this time, the abutment portion 152b is biased upward by the biasing force of the upward biasing member 156, and therefore moves upward while contacting the recessed portion 33d. In this state, as shown in FIG. 10(b), the check plate 52a rises relative to the guide plate 44. Thus, in the second embodiment as well, the check portion 152 is raised and lowered by rotating the handlebar 30, thereby preventing the gear shift operating device 41 from being operated to a predetermined gear.

[0091] As described above, the guide surface 33c according to the second embodiment has the following features: It is formed on the lower end surface of the rotating member (the inner cylindrical portion 33b of the handle 30). By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0092] Further, the walk-behind working machine 1 according to the second embodiment has: The device further includes an upward biasing member 156 that biases the check portion 152 upward. By configuring in this way, the check section 152 can be operated smoothly.

[0093] Next, a modified example of the second embodiment will be described with reference to FIG.

[0094] This modified example differs from the second embodiment in that the check portion 152 is guided by a guide groove 33e formed on the side surface of the inner cylindrical portion 33b, rather than by a guide surface 33c formed on the lower end surface of the inner cylindrical portion 33b.

[0095] The guide groove 33e is formed by recessing the side surface of the inner cylindrical portion 33b near the lower end thereof by a predetermined depth. The guide groove 33e is formed to extend in the circumferential direction of the inner cylindrical portion 33b. More specifically, the guide groove 33e includes an upper groove 33f extending horizontally, a lower groove 33g formed at a lower position than the upper groove 33f and extending horizontally, and an inclined groove 33h formed to connect the upper groove 33f and the lower groove 33g and extending in an oblique direction. The tip of the abutment portion 152b is inserted into the guide groove 33e.

[0096] In this modified example, as shown in Figure 17(a), when the handle 30 is in the forward handle position, the contact portion 152b is located in the lower groove 33g. When the handle 30 is rotated from the forward handle position to the reverse handle position (see Figure 17(b)), the contact portion 152b rises so as to ride onto the upper groove 33f via the inclined groove 33h. In other words, the contact portion 152b is displaced in the direction of the rotation axis of the handle 30 in response to the rotation of the handle 30 (inner cylindrical portion 33b).

[0097] Furthermore, when the handle 30 is rotated from the reverse handle position to the normal handle position, the contact portion 152b is pushed down by the inclined groove 33h and moves to the lower groove 33g (see FIG. 17(a)). In this manner, in this modified example, the check portion 152 moves up and down while being guided by the guide groove 33e.

[0098] As described above, the guide groove 33e for guiding the check portion 152 is formed on the side surface of the rotating member (inner cylindrical portion 33b) in this modified example, which faces in the direction of the rotation axis. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0099] Although the second embodiment has been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention described in the claims.

[0100] For example, in the second embodiment, an example is shown in which the lower end surface (guide surface 33c) of the inner cylindrical portion 33b pushes down the check portion 152 (see Figure 16, etc.), but it is also possible to form a part (flange, etc.) that protrudes radially outward from the side surface of the inner cylindrical portion 33b, and configure the check portion 152 to be pushed up from below by this part.

[0101] In addition, in the second embodiment, an example is shown in which the check portion 152 (contact portion 152b) descends when the handle 30 is switched to the forward handle position, and the check portion 152 ascends when the handle 30 is switched to the reverse handle position (see Figure 16, etc.), but the relationship between the rotation of the handle 30 and the operating direction of the check portion 152 is not limited to this and can be changed as desired.

[0102] The following describes a check mechanism 250 and the like according to a third embodiment of the present invention (see FIGS. 18 to 23). In the description of the third embodiment, differences from the first embodiment will be mainly described, and components that are generally similar to those in the first embodiment will be assigned the same reference numerals and will not be described again.

[0103] The third embodiment differs from the first embodiment mainly in the configurations of the gear shift operation mechanism 240 and the check mechanism 250. This will be explained in detail below.

[0104] The gear shift operation mechanism 240 shown in FIGS. 18 to 20 differs from the first embodiment mainly in the configuration of the guide rod 243 and the guide plate 244.

[0105] Unlike the guide rod 43 according to the first embodiment (see FIG. 4 etc.), the guide rod 243 according to the third embodiment is arranged so as to protrude upward. Specifically, the lower end of the guide rod 243 is fixed to the link mechanism 42. The upper part of the guide rod 243 is arranged so as to protrude upward from the link mechanism 42.

[0106] Unlike the guide plate 44 according to the first embodiment (see FIG. 4, etc.), the guide plate 244 according to the third embodiment is arranged with its plate surface facing up and down. The guide plate 244 is fixed to the left side surface of the support base main body 21. The guide plate 244 is arranged immediately below a slit 21c formed by cutting out the left side surface of the support base main body 21 in the front-rear direction from the front end to the vicinity of the rear end. A guide groove G is formed in the guide plate 244.

[0107] As shown in Fig. 21, the guide groove G according to the third embodiment is formed to penetrate the guide plate 244 from top to bottom. The guide groove G is formed in a shape (longitudinal shape) that extends long in the front-rear direction as a whole. The guide groove G mainly includes a longitudinal groove GV and a plurality of lateral grooves GS.

[0108] The longitudinal groove GV is a linear portion extending long in the front-rear direction. The lateral groove GS is a linear portion extending long in the left-right direction. The length of the lateral groove GS is formed to be shorter than the length of the longitudinal groove GV. The multiple lateral grooves GS are formed to be aligned at approximately equal intervals from the front end to the rear end of the longitudinal groove GV. In this embodiment, five lateral grooves GS are formed. The multiple lateral grooves GS are formed to extend left and right from the longitudinal groove GV.

[0109] The guide rod 243 is inserted into the guide groove G of the guide plate 244. As a result, the movable direction of the guide rod 243 is restricted by the guide groove G, and the guide rod 243 is guided to move along the shape of the guide groove G. In other words, the gear shift operation (operation direction) by the gear shift operating device 41 is guided by the guide groove G.

[0110] Furthermore, guide groove G is formed to have a shape corresponding to each gear position of the walk-behind working machine 1. Specifically, when the transmission mechanism is switched to one of the gear positions (forward first gear, forward second gear, ..., reverse first gear, reverse second gear, ..., etc.), guide rod 43 is set to be located at either the left or right end of the multiple lateral grooves GS (shift positions P1 to P10 shown in FIG. 6). The correspondence between the gear positions of the transmission mechanism and the shift positions P in guide groove G is not particularly limited, and can be set arbitrarily depending on the configuration of the transmission mechanism, etc.

[0111] 19, 20 and 22 inhibits (restricts) the gear shift operation to a predetermined gear position by the gear shift operating device 41. The inhibiting mechanism 250 mainly comprises a rotating member 251 and an inhibiting portion 252.

[0112] The rotating member 251 is used to move a check portion 252 (described later) in accordance with the position of the handle 30. The rotating member 251 is formed in a flat plate shape with its plate surface facing up and down. The rotating member 251 is formed in a circular shape in a plan view. The rotating member 251 is fixed to the lower end of the inner cylindrical portion 33b of the handle 30 inside (below the upper surface of) the support base main body 21. This allows the rotating member 251 to rotate integrally with the handle 30. The rotating member 251 is formed with a first protrusion 251a and a second protrusion 251b.

[0113] The first protruding portion 251a and the second protruding portion 251b are portions that can come into contact with a check portion 252, which will be described later. The first protruding portion 251a and the second protruding portion 251b are formed so as to protrude radially outward from the outer periphery of the rotating member 251. The first protruding portion 251a and the second protruding portion 251b are formed at opposite positions across the rotation axis of the rotating member 251.

[0114] The check portion 252 blocks the guide groove G of the guide plate 244, thereby preventing the gear shift operation of the gear change operating device 41 to a predetermined gear position. The check portion 252 is formed by appropriately bending a plate-shaped member. The check portion 252 is arranged so as to protrude leftward from the inside of the support base main body 21 through the slit 21c of the support base main body 21. The right portion of the check portion 252 (the portion located inside the support base main body 21) is arranged near the rotating member 251 (a position that can come into contact with the first protrusion 251a and the second protrusion 251b). The left portion of the check portion 252 (the portion located outside the support base main body 21) is arranged immediately below the guide plate 244. The check portion 252 is arranged so as to be movable along the longitudinal direction (front-rear direction) of the slit 21c. That is, the check portion 252 can be displaced in a direction perpendicular to the rotation axis direction (up and down direction) of the rotating member 251 (handle 30). As shown in Fig. 22, the left portion of the check portion 252 is formed with a first check portion 252a, a connecting portion 252b, and a second check portion 252c.

[0115] The first check portion 252a is a portion formed to extend in the left and right directions. The left and right width of the first check portion 252a is formed to be larger than the left and right width of the guide groove G of the guide plate 244.

[0116] The connecting portion 252b is a portion that connects the first checking portion 252a and the second checking portion 252c, which will be described later. The connecting portion 252b is formed to extend rearward from the left end of the first checking portion 252a. The connecting portion 252b is formed to be located to the left of the guide groove G in a plan view.

[0117] The second check portion 252c is a portion formed to extend laterally. The second check portion 252c is formed to extend rightward from the rear end of the connecting portion 252b. The right end of the second check portion 252c is formed to be located immediately in front of (immediately to the left of) the longitudinal groove GV in a plan view. In this way, the second check portion 252c is formed to leave a predetermined distance between it and the first check portion 252a in the front-rear direction.

[0118] The following describes how the speed change operation of the speed change operating device 41 is restricted in the walk-behind working machine 1 configured as described above.

[0119] First, the state in which the handle 30 is switched to the normal handle position will be described.

[0120] When the handle 30 is switched to the normal handle position, the first protrusion 251a of the rotating member 251 is positioned at the front left, as shown in Fig. 22. In this state, the first protrusion 251a abuts against the right end of the check part 252 from behind. By being pushed from behind by the first protrusion 251a, the check part 252 is moved forward relative to the guide plate 244 to a position (first check position).

[0121] In this state, a portion of guide groove G is blocked from below by check portion 252. Specifically, second check portion 252c of check portion 252 is positioned so as to block shift position P8 from below. This prevents guide rod 243 of gear change operation mechanism 40 from moving to shift position P8, and therefore prevents gear changes to the gear corresponding to that gear position. For example, if a gear that moves at high speed in the reverse direction (a gear that is not expected to be used with the handlebars in the normal position) is set as the gear corresponding to shift position P8, workability can be improved by preventing gear changes to that gear in advance.

[0122] Next, the manner in which the handle 30 is switched to the reverse handle position will be described.

[0123] When the handle 30 is switched from the forward handle position to the reverse handle position, the handle 30 is rotated counterclockwise in a plan view about the fulcrum shaft 22. When the handle 30 rotates, the rotating member 251 rotates integrally with the handle 30.

[0124] 23, when the rotating member 251 rotates, the second protrusion 251b abuts against the right end of the check portion 252 from the front. By being pressed from the front by the second protrusion 251b, the check portion 252 is displaced rearward relative to the guide plate 244 (second check position).

[0125] Next, a state in which the handle 30 is switched to the reverse handle position will be described.

[0126] When the handle 30 is switched to the reverse handle position (see FIG. 23), the check section 252 is located further rearward than when the handle 30 is in the normal handle position (see FIG. 22, etc.).

[0127] In this state, a portion of the guide groove G is blocked from below by the check portion 252. Specifically, the second check portion 252c of the check portion 252 is positioned so as to block shift position P6 from below. Furthermore, the first check portion 252a of the check portion 252 is positioned so as to block shift position P9 and shift position P10 from below. This prevents the guide rod 243 of the gear change operation mechanism 40 from moving to shift position P6, P9, or P10, thereby blocking gear changes to the gears corresponding to those portions. For example, if gears that move at high speed in the reverse direction (gears that are not expected to be used with the handlebars in the reverse position) are set as gears corresponding to shift position P6, P9, and P10, blocking gear changes to those gears in advance can improve operability.

[0128] Conversely to the above, when the handlebar 30 is switched from the reverse handlebar position (see FIG. 23) to the normal handlebar position (see FIG. 22), the first protrusion 251a of the turning member 251 presses the check part 252 forward, and the shift position P8 is again blocked. In this way, the check mechanism 250 can automatically check the gear shift operation by the gear change operating device 41 to a predetermined gear position as the handlebar 30 is turned.

[0129] As described above, the walk-behind working machine 1 according to the third embodiment has the following features: a speed change operation device 41 capable of speed change operation; a handle 30 that is rotatable between a first working position (normal handle position) and a second working position (reverse handle position) that is inverted from the first working position; a rotating member 251 that is rotatable integrally with the handle 30, has protrusions (a first protrusion 251a and a second protrusion 251b) that protrude radially outward, and uses the protrusions to inhibit the gear shift operation of the gear shift operating device 41 to a predetermined gear position; It is equipped with the following. With this configuration, it is possible to prevent the gear shift operating device 41 from being operated to a predetermined gear position in response to the rotation of the handle 30. This improves workability. Furthermore, the above configuration simplifies the mechanism for preventing this.

[0130] Furthermore, the walk-behind working machine 1 according to the third embodiment has It further includes a check portion 252 that is arranged so as to be able to come into contact with the protrusion, is displaced by being pressed against the protrusion in accordance with the rotation of the rotating member 251, and checks the operation of the speed change operating device 41 to a predetermined gear stage. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0131] In addition, the check section 252 is The rotating member 251 is displaced in a direction perpendicular to the rotation axis direction. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0132] Moreover, the protrusion is A first protruding portion 251a, a second protruding portion (251b) different from the first protruding portion (251a), The check section 252 is When the handle 30 is rotated to the first working position, the handle 30 is pressed by the first protrusion 251a and displaced to the first inhibiting position, When the handle 30 is rotated to the second working position, the handle 30 is pressed by the second protruding portion 251b and is displaced to the second inhibiting position. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0133] Furthermore, the walk-behind working machine 1 according to the third embodiment has The gear shifter further includes a guide plate 244 (guide plate) having a guide groove G formed therein for guiding the gear shift operation of the gear shift operating device 41, The check section 252 is By blocking a portion of the guide groove G, the gear shift operation of the gear shift operating device 41 to a predetermined gear position is inhibited. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0134] Although the third embodiment has been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention described in the claims.

[0135] For example, the arrangement, shape, etc. of each member such as the rotating member 251 and the check portion 252 exemplified in the third embodiment can be changed as desired.

[0136] The following describes a check mechanism 350 and the like according to a fourth embodiment of the present invention (see FIGS. 24 to 27). In the description of the fourth embodiment, differences from the third embodiment will be mainly described, and components that are generally similar to those in the third embodiment will be assigned the same reference numerals and will not be described again.

[0137] The fourth embodiment differs from the check mechanism 250 according to the third embodiment mainly in the configuration of a check mechanism 350. The check mechanism 350 according to the fourth embodiment mainly includes a rotating member 351.

[0138] 24 to 26 blocks the guide groove G of the guide plate 244, thereby preventing the speed change operation of the speed change operating device 41 to a predetermined gear position. The rotating member 351 is formed in the shape of a flat plate with its plate surface facing up and down. The rotating member 351 mainly includes a main body portion 351a and a protrusion portion 351b.

[0139] The main body 351a is a portion that is fixed to the inner cylindrical portion 33b of the handle 30. The main body 351a is formed in a generally circular shape in a plan view. The main body 351a is fixed to the lower end of the inner cylindrical portion 33b of the handle 30 inside (below the upper surface of) the support base main body 21. This allows the rotating member 351 to rotate integrally with the handle 30.

[0140] The protrusion 351b is a portion that blocks the guide groove G of the guide plate 244, thereby inhibiting the gear shift operation of the gear shift operating device 41 to a predetermined gear position. The protrusion 351b is formed to protrude radially outward from the main body 351a. The protrusion 351b is formed to protrude to the left side of the support base main body 21 through the slit 21c of the support base main body 21 when the rotating member 351 is rotated to a predetermined position (the position shown in FIG. 24). In this state, the left part of the protrusion 351b (the part located outside the support base main body 21) is located immediately below the guide plate 244. As shown in FIGS. 26 and 27, the protrusion 351b is formed with a first inhibiting portion 351c, a connecting portion 351d, and a second inhibiting portion 351e.

[0141] The shapes of the first check portion 351c, the connecting portion 351d and the second check portion 351e are generally similar to those of the first check portion 252a, the connecting portion 252b and the second check portion 252c according to the third embodiment (see Figure 22, etc.), and therefore detailed explanations will be omitted.

[0142] The following describes how the speed change operation of the speed change operating device 41 is restricted in the walk-behind working machine 1 configured as described above.

[0143] First, the state in which the handle 30 is switched to the normal handle position will be described.

[0144] When the handlebars 30 are switched to the normal handlebar position, the protruding portion 351b of the rotating member 351 is located at the rear right, as shown in Figure 26. In this state, the protruding portion 351b does not block the guide groove G of the guide plate 244, and therefore the gear shifting operation is not inhibited.

[0145] Next, a state in which the handle 30 is switched to the reverse handle position will be described.

[0146] When the handle 30 is switched from the forward handle position to the reverse handle position, the handle 30 is rotated counterclockwise in a plan view about the fulcrum shaft 22. When the handle 30 rotates, the rotating member 351 rotates integrally with the handle 30.

[0147] When the rotating member 351 rotates, the protrusion 351b moves below the guide plate 244, as shown in FIG. 27. In this state, the protrusion 351b blocks part of the guide groove G from below. Specifically, the second check portion 351e of the protrusion 351b is positioned so as to block the shift position P6 from below. Furthermore, the first check portion 351c of the protrusion 351b is positioned so as to block the shift positions P9 and P10 from below. This prevents the guide rod 243 of the gear shift operation mechanism 40 from moving to the shift position P6, P9, or P10, thereby inhibiting the gear shift operation to the gear corresponding to that portion. For example, if a gear stage that moves in the reverse direction at high speed (a gear stage that is not expected to be used in the reverse handle position) is set as the gear stage corresponding to gear positions P6, P9, and P10, workability can be improved by preventing the gear change operation to that gear stage in advance.

[0148] Conversely to the above, when the handlebars 30 are switched from the reverse handlebar position (see FIG. 27) to the normal handlebar position (see FIG. 26), the protrusions 351b move away from the guide plate 244, and the restriction on gear shifting is released. In this way, the restriction mechanism 350 can automatically restrict the gear shifting operation to a predetermined gear by the gear shift operating device 41 as the handlebars 30 are turned.

[0149] As described above, the walk-behind working machine 1 according to the fourth embodiment has the following features: The gear shifter further includes a guide plate 244 (guide plate) having a guide groove G formed therein for guiding the gear shift operation of the gear shift operating device 41, The protrusion 351b is By blocking a portion of the guide groove G, the gear shift operation of the gear shift operating device 41 to a predetermined gear position is inhibited. By configuring in this way, it is possible to restrain the gear shift operation with a simple configuration.

[0150] Although the fourth embodiment has been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention described in the claims.

[0151] For example, in the fourth embodiment, the rotating member 351 has one protrusion 351b to inhibit gearshift operation, but the present invention is not limited to this. For example, it is also possible to form two or more protrusions on the rotating member 351 to inhibit gearshift operation to a predetermined gear position in both the forward handle position and the reverse handle position.

[0152] Furthermore, in each of the above embodiments, an example has been shown in which a check section (such as check section 52 shown in FIG. 4) is moved in conjunction with the rotation of handle 30 to check the gear shift operation, but the present invention is not limited to this. For example, if walk-behind working machine 1 is provided with an operating device for checking the gear shift operation (such as an operating device that can arbitrarily operate check section 52), it is also possible to configure the operating device to operate in conjunction with the rotation of handle 30. This makes it possible to automatically operate the operating device according to the position of handle 30 and check a specified gear shift operation.

[0153] Furthermore, the shift positions and gear stages that are restrained as shown in the above embodiments are merely examples, and it is possible to appropriately set any shift position (gear stage) to be restrained.

[0154] Furthermore, there are no particular limitations on the relationship between the position of the handlebar 30 and whether or not a gearshift operation is inhibited. That is, it is possible to configure the system so that a predetermined gearshift operation is inhibited when the handlebar 30 is switched to the forward handlebar position and when it is switched to the reverse handlebar position, or to configure the system so that a predetermined gearshift operation is inhibited only when the handlebar 30 is switched to either one of the positions.

[0155] Furthermore, the shape of the guide groove G illustrated in this embodiment is merely an example, and the present invention is not limited to this. The shape of the guide groove G can also be formed, for example, in a substantially linear shape or an H-shape. [Explanation of symbols]

[0156] 1 Walk-behind work machine 30 Handle 40 Gear shifting mechanism 41 Gear shifting device 44 Guide plate 50 Checking Mechanism 51 Rotating member 52 Checking Section G guide groove

Claims

1. A speed change operation device capable of speed change operation; a handle that is rotatable between a first working position and a second working position that is inverted from the first working position; a rotating member that can rotate integrally with the handle; a check portion that is disposed in contact with the rotating member and displaces in a direction of a rotation axis of the rotating member in conjunction with the rotation of the rotating member, thereby checking the speed change operation of the speed change operating device to a predetermined speed; A walk-behind work machine equipped with the above.

2. a guide surface for guiding the check portion is formed on an end surface of the rotating member in the direction of the rotation axis, The guide surface is a tilted portion whose position in the direction of the rotation axis changes along the circumferential direction of the rotating member; The walk-behind working machine according to claim 1.

3. The guide surface is formed on the upper end surface of the rotating member, The walk-behind working machine according to claim 2.

4. The vehicle further includes a downward biasing member that biases the check portion downward. The walk-behind working machine according to claim 3.

5. The guide surface is A lower end surface of the rotating member is formed. The walk-behind working machine according to claim 2.

6. The device further includes an upward biasing member that biases the check portion upward. The walk-behind working machine according to claim 5.

7. The rotating member is a first rotating member; a second rotating member disposed on one side of the first rotating member in the direction of the rotation axis; Including, a guide surface for guiding the check portion formed on the opposing end surfaces of the first rotating member and the second rotating member; The walk-behind working machine according to claim 1.

8. A guide groove for guiding the check portion is formed on a side surface of the rotating member in the direction of the rotation axis. The walk-behind working machine according to claim 1.

Images