Walking-type work machine

Abstract

To provide a walking-type work machine capable of improving operability in adjusting the vertical position of a control handle.SOLUTION: A walking-type work machine 1 comprises: a control handle 11 that is swingable in the vertical direction; and a handle position adjustment mechanism 20 capable of adjusting the vertical position of the control handle 11. The handle position adjustment mechanism 20 comprises: a restriction mechanism 30 capable of restricting the swinging motion of the control handle 11; and a spring 80 that urges the control handle 11 upward. The spring 80 applies a biasing force to the control handle 11 in a direction inclined with respect to the circumferential direction around the swing fulcrum of the control handle 11.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a technique for a walk-behind working machine having a handle that can swing up and down. [Background technology]

[0002] Conventionally, there is known a technique for a walk-behind working machine having a handle that can swing up and down, as described in Patent Document 1, for example.

[0003] The walk-behind working machine described in Patent Document 1 includes a handle and a handle height adjustment mechanism. The handle is provided on a transmission case and can swing up and down. The handle height adjustment mechanism includes a lock pin and a fixing hole. The lock pin is formed so as to be able to engage with the fixing hole. The lock pin is connected to a handle adjustment lever provided on the handle via a handle adjustment wire. The lock pin can engage and disengage with the fixing hole in response to operation of the handle adjustment lever.

[0004] The operator can swing the handle up and down by releasing the engagement between the lock pin and the fixing hole. The operator can also fix the handle at a specified swing position by engaging the lock pin with the fixing hole. In this way, the handle height adjustment mechanism allows the operator to adjust the vertical position of the handle.

[0005] However, the handle tends to swing downward due to its own weight, so a relatively large force is required to swing the handle upward. In addition, due to the weight, when the lock pin is disengaged from the fixing hole, the handle may swing downward unintentionally. Thus, in the conventional technology, there is room for improvement in the operability when adjusting the vertical position of the handle. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2011-182751 A 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 situation, and the problem it aims to solve is to provide a walk-behind working machine that can improve operability when adjusting the up and down position of the handle. [Means for solving the problem]

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

[0009] One aspect of the present disclosure is a walk-behind working machine comprising a handle capable of swinging in an up-down direction and a handle position adjustment mechanism capable of adjusting the up-down position of the handle, wherein the handle position adjustment mechanism comprises a regulating mechanism capable of regulating the swinging of the handle and a biasing member that biases the handle upward. According to one aspect of the present disclosure, it is possible to improve operability when adjusting the up and down position of the handle.

[0010] In one aspect of the present disclosure, the biasing member applies a biasing force to the handle in a direction inclined with respect to a circumferential direction about a pivot point of the handle. According to one aspect of the present disclosure, the biasing member can prevent an excessive biasing force from being applied to the handle.

[0011] In one aspect of the present disclosure, the biasing member is configured by a compression coil spring and is disposed so that the direction of expansion and contraction is inclined upward toward the rear. According to one aspect of the present disclosure, by arranging the biasing member so as to follow the orientation of a typical handle, it is possible to achieve a more compact arrangement and improved design.

[0012] In one aspect of the present disclosure, the biasing member is disposed in a central portion in the left-right width of the handle. According to one aspect of the present disclosure, a biasing force can be applied to the handle without bias to the left or right.

[0013] In one aspect of the present disclosure, the handle comprises a handle body pivotally connected to both left and right side surfaces of the transmission case, and one end of the biasing member is connected to a connecting member that connects the left and right portions of the handle body. According to one aspect of the present disclosure, the biasing member can be connected to the handle with a simple configuration.

[0014] In one aspect of the present disclosure, the regulating mechanism includes a first regulating member that can swing integrally with the handle and a second regulating member that is fixed to a transmission case and can engage with the first regulating member, and one end of the biasing member is connected to the second regulating member. According to one aspect of the present disclosure, the biasing member can be connected to the airframe with a simple configuration. Effect of the Invention

[0015] According to one aspect of the present disclosure, it is possible to improve operability when adjusting the up and down position of the handle. [Brief description of the drawings]

[0016] [Figure 1] 1 is a side view showing a walk-behind working machine according to an embodiment of the present invention; [Diagram 2] FIG. [Diagram 3] FIG. 4 is a side view showing the transmission case, the steering handle, and the handle position adjustment mechanism. [Figure 4] Also, rear view. [Diagram 5] FIG. 4 is a perspective view showing a connecting member of the steering handle and a handle position adjustment mechanism. [Figure 6] Also, side view. [Figure 7] FIG. [Figure 8] FIG. 4 is a side view showing the state in which the operating handle is swung in the up and down direction. [Figure 9] FIG. 4 is a side view showing the relationship between the circumferential direction about the pivot shaft and the biasing direction of a spring. [Figure 10] 1A is a schematic rear view of the spring and the handle of the embodiment, and FIG. 1B is a schematic rear view of the spring and the handle of a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] 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.

[0018] Hereinafter, with reference to FIG. 1, a walk-behind working machine (walk-behind management machine) 1 according to one embodiment of the present invention will be described.

[0019] The walk-behind work machine 1 comprises a machine frame 2, wheels 3, an engine 4, a bonnet 5, a cover 6, a transmission case 7, tillage tines 8, a tillage cover 9, a clutch mechanism 10, and a steering handle 11, etc.

[0020] The vehicle frame 2 is a member formed by appropriately bending a plate material. The vehicle frame 2 is supported by a pair of left and right wheels 3. The engine 4 is mounted on the vehicle frame 2. The engine 4 is covered by a bonnet 5. A cover 6 is provided on the left side of the engine 4, which covers a clutch mechanism 10 that transmits the power of the engine 4 to a transmission case 7.

[0021] The transmission case 7 has a rotating shaft 7a that rotates when power is transmitted from the engine 4. The tillage tines 8 are fixed to the rotating shaft 7a. The upper part of the tillage tines 8 is covered with a tillage cover 9. The clutch mechanism 10 is for switching between rotating and stopping the rotation of the wheels 3 and the tillage tines 8. The clutch mechanism 10 in this embodiment is assumed to be a so-called belt tension clutch that can transmit power by applying tension to a belt wound around a pulley.

[0022] A control handle 11 is disposed above the tillage cover 9. The control handle 11 is for an operator to control the tillage cover 9. The control handle 11 is provided with an operable clutch lever 11a, and the clutch lever 11a is connected to the clutch mechanism 10 via a cable.

[0023] In the walk-behind work machine 1 configured as described above, when the clutch lever 11a of the steering handle 11 is operated, tension is applied to the belt and the clutch mechanism 10 is actuated. This transmits power from the engine 4 to the wheels 3 and the rotating shaft 7a. This enables the walk-behind work machine 1 to rotate the wheels 3 and the tilling tines 8 to till the field.

[0024] Furthermore, in the walk-behind work machine 1, when the operation of the clutch lever 11a is released, the application of tension to the belt is stopped and the operation of the clutch mechanism 10 is stopped. This causes the rotation of the wheels 3 and the tiller tines 8 to stop.

[0025] The steering handle 11 will be described below with reference to Figures 1 to 7. The steering handle 11 comprises a handle body 12, a swing shaft 13, a connecting member 14, and a vertical adjustment lever 15.

[0026] The handle body 12 shown in Figures 1 and 2 is a part that forms the main structure of the steering handle 11. The handle body 12 is formed by appropriately bending a substantially cylindrical member. The handle body 12 is provided so as to incline upward toward the rear in a side view. The handle body 12 is formed symmetrically. As shown in Figure 2, the handle body 12 includes an attachment portion 12a, a first extension portion 12b, a second extension portion 12c, and a grip portion 12d.

[0027] 2 and 3 is a portion that is attached to the transmission case 7. The mounting portion 12a is formed in a generally plate-like shape with its plate surface facing left and right. A pair of left and right mounting portions 12a are provided. The pair of left and right mounting portions 12a are disposed on the left and right outer sides of the transmission case 7, respectively.

[0028] The first extending portions 12b extend upward and rearward from the pair of left and right mounting portions 12a. The second extending portions 12c extend further upward and rearward from the pair of left and right first extending portions 12b. The pair of left and right second extending portions 12c are formed to extend upward and rearward from the first extending portions 12b while spreading outward to the left and right.

[0029] Various operating tools such as the clutch lever 11a shown in Fig. 1 are provided on the pair of left and right second extending portions 12c. Furthermore, a cable C that connects the operating tools to various members is provided on the pair of left and right second extending portions 12c so as to extend along the second extending portions 12c. For the sake of convenience of explanation, only a cable C32 that connects a vertical adjustment lever 15 and an engagement pin 32, which will be described later, is shown among the multiple cables C in the drawings other than Figs. 1 and 8.

[0030] 1 and 2 is a portion that is gripped by an operator who operates the walk-behind work machine 1. The grip portion 12d is formed so as to connect the rear upper end portions of the pair of left and right second extending portions 12c.

[0031] The pivot shaft 13 shown in Figs. 1 and 3 is for supporting the handle body 12 so that it can pivot. The pivot shaft 13 is formed in a generally cylindrical shape with its axis oriented in the left-right direction. In this embodiment, a bolt that can be inserted into the mounting portion 12a is used as the pivot shaft 13. A pair of pivot shafts 13 are provided on the left and right. The pair of left and right mounting portions 12a are inserted into the pair of left and right pivot shafts 13, respectively. The pair of left and right pivot shafts 13 are fastened to female threaded portions (not shown) formed on the left and right side surfaces of the transmission case 7, respectively. The pivot shafts 13 connect the handle body 12 to the left and right side surfaces of the transmission case 7, and the handle body 12 can pivot up and down relative to the transmission case 7 around the pivot shafts 13.

[0032] 2 to 4 is a member for connecting the pair of left and right first extending portions 12b (the left and right portions of the steering handle 11) to each other. The connecting member 14 includes a plate portion 14a, a bent portion 14b, a guide portion 14c, and an extending portion 14d.

[0033] The plate portion 14a shown in Figures 2, 5, and 6 is a plate-shaped portion extending in the left and right direction. The plate portion 14a is formed so as to bulge upward from both left and right ends toward the left and right center. The plate portion 14a is disposed in an inclined position with respect to the up-down direction so as to be aligned along the direction in which the first extending portion 12b extends from the mounting portion 12a (rearward and upward). The left and right ends of the plate portion 14a are fixed to the pair of left and right first extending portions 12b, respectively.

[0034] The bent portions 14b are formed so as to bend downward from the upper and lower ends of the plate portion 14a, and are formed so as to extend from the left end to the right end of the plate portion 14a.

[0035] The guide portion 14c shown in Fig. 6 and Fig. 7 is a portion for guiding an engagement pin 32 described later. The guide portion 14c is formed in a cylindrical shape. The guide portion 14c is disposed so as to incline upward toward the rear. The guide portion 14c is provided so as to penetrate the left and right central portions of the upper and lower bent portions 14b, respectively.

[0036] The extending portion 14d shown in Figures 5 and 6 is a portion extending rearward and upward from the upper bent portion 14b. The extending portion 14d is formed in a generally plate-like shape with the plate surface facing in the left-right direction. The extending portions 14d are provided on the left and right sides of the guide portion 14c (a pair of left and right portions). The extending portion 14d is formed with a through hole 14e penetrating in the thickness direction.

[0037] The up-down adjustment lever 15 shown in Fig. 1 is operated to adjust the up-down position of the steering handle 11. The up-down adjustment lever 15 is supported so as to be able to swing on the second extension portion 12c on the right side of the steering handle 11. By swinging the up-down adjustment lever 15, the operator can operate the handle position adjustment mechanism 20 and adjust the up-down position of the steering handle 11.

[0038] The handle position adjustment mechanism 20 will be described below with reference to Figures 1, 5 to 7. The handle position adjustment mechanism 20 is for adjusting the up and down position of the steering handle 11. The handle position adjustment mechanism 20 includes a restriction mechanism 30, a first mounting member 40, a first pivot shaft 50, a second mounting member 60, a second pivot shaft 70, and a spring 80.

[0039] 7 is for restricting the vertical swing of the steering handle 11 (handle body 12) relative to the transmission case 7. The restricting mechanism 30 includes a handle frame 31 and an engagement pin 32.

[0040] 5 to 7 is a member fixed to the transmission case 7. The handle frame 31 includes a side plate portion 31a, a through hole 31b, an engagement portion 31c, and a hole portion 31d.

[0041] The side plate portion 31a shown in Fig. 6 is a plate-shaped portion with a plate surface facing substantially in the left-right direction. A pair of left and right side plate portions 31a are provided. The pair of left and right side plate portions 31a are fixed to both left and right side surfaces of the transmission case 7. The handle body 12 (first extension portions 12b) are disposed on the left and right outer sides of the side plate portions 31a (see Fig. 3).

[0042] The through holes 31b are holes that penetrate the side plate portions 31a in the thickness direction and are formed in the rear lower end portions of the pair of left and right side plate portions 31a, respectively.

[0043] The engaging portion 31c shown in Figs. 5 and 7 is a portion that can engage with the engaging pin 32. The engaging portion 31c is formed so as to connect the rear upper end portions of the pair of left and right side plate portions 31a to each other. The engaging portion 31c is formed in a circular arc shape in a side view along the circumferential direction centered on the swing shaft 13 (see Fig. 6). The connecting member 14 of the steering handle 11 is disposed above and behind the engaging portion 31c. The front upper end portion and the rear lower end portion of the engaging portion 31c are formed so as to be bent upward and rearward. When the steering handle 11 is swung in the vertical direction, the connecting member 14 (guide portion 14c) abuts against the bent portion. In this way, the steering handle 11 can be swung up and down within a range between the position where the connecting member 14 abuts against the front upper end portion of the engaging portion 31c and the position where it abuts against the rear lower end portion.

[0044] The hole 31d is a hole penetrating the engagement portion 31c in the thickness direction. A plurality of holes 31d are formed in the circumferential direction centered on the oscillation shaft 13 (see FIG. 6). In this embodiment, four holes 31d are formed. Note that the number of holes 31d is not limited to this embodiment as long as it is two or more.

[0045] The engagement pin 32 shown in Fig. 7 is a columnar member that can engage with a hole 31d of the handle frame 31. The engagement pin 32 is inserted into a guide portion 14c of the connecting member 14 and is formed to be slidable relative to the guide portion 14c. In the state shown in Fig. 7, the front lower end portion of the engagement pin 32 protrudes from the guide portion 14c toward the handle frame 31 and is engaged with the hole 31d. By engaging the engagement pin 32 with the hole 31d in this manner, the restriction mechanism 30 can restrict the swinging of the steering handle 11 in the up and down direction.

[0046] The engagement pin 32 is connected to the up-down adjustment lever 15 shown in FIG. 1 via a cable C32 or the like. The engagement pin 32 is biased toward the handle frame 31 by a spring S32 provided in the guide portion 14c. The operator can move the engagement pin 32 away from the handle frame 31 against the biasing force of the spring S32 by gripping the up-down adjustment lever 15 (swinging it upward relative to the handle body 12) (see FIG. 8). This causes the engagement pin 32 to be pulled out of the hole 31d, and the engagement with the hole 31d is released (restriction on swinging the steering handle 11 is released). In this state, the engagement pin 32 can swing up and down together with the steering handle 11.

[0047] When the operator releases the up-down adjustment lever 15, the engagement pin 32 is biased by the spring S32 toward the handle frame 31 and engages with the hole 31d. In this manner, the restriction mechanism 30 can switch between restricting and releasing the restriction on the swing of the operating handle 11.

[0048] 5 and 7 is a member for attaching a lower end portion of a spring 80 described later. The first attachment member 40 includes a cylindrical portion 41, an extending portion 42, and a spring receiving portion 43.

[0049] The tubular portion 41 is a cylindrical portion whose axis direction is oriented in the left-right direction and is disposed between the rear lower ends of the pair of left and right side plate portions 31a.

[0050] The extending portion 42 is a portion extending from the cylindrical portion 41. The extending portion 42 is formed in a substantially cylindrical shape. The extending portion 42 is formed so as to extend rearward and upward from the left-right central portion of the cylindrical portion 41. An upper end portion of the extending portion 42 is located near the extending portion 14d of the connecting member 14.

[0051] The spring receiving portion 43 is a portion that receives the lower end portion of the spring 80. The spring receiving portion 43 is formed in a disk shape. The spring receiving portion 43 is fixed to the lower portion of the extension portion .

[0052] The first oscillating shaft 50 is for supporting the first mounting member 40 so that it can oscillate. The first oscillating shaft 50 is formed in a generally cylindrical shape with its axis oriented in the left-right direction. The first oscillating shaft 50 is inserted through a pair of left and right side plate portions 31a (through holes 31b) of the handle frame 31 and the cylindrical portion 41 of the first mounting member 40. This connects the first mounting member 40 to the handle frame 31 via the first oscillating shaft 50. The first mounting member 40 can oscillate relative to the handle frame 31 around the first oscillating shaft 50.

[0053] The second mounting member 60 is a member for mounting the upper end portion of the spring 80. The second mounting member 60 includes a first cylindrical portion 61, a second cylindrical portion 62, and a spring receiving portion 63.

[0054] The first tubular portion 61 is a cylindrical portion whose axial direction faces the left-right direction. The first tubular portion 61 is disposed between the pair of left and right extending portions 14d of the connecting member 14.

[0055] The second cylindrical portion 62 is a cylindrical portion whose axial direction is oriented in the same direction as the extending portion 42 of the first mounting member 40. The second cylindrical portion 62 is fixed to the left-right center portion of the first cylindrical portion 61. The extending portion 42 is inserted into the second cylindrical portion 62.

[0056] The spring receiving portion 63 is a portion that receives the upper end portion of the spring 80. The spring receiving portion 63 is formed in a disk shape. The spring receiving portion 63 is fixed to the lower end portion of the second cylindrical portion 62. The spring receiving portion 63 is disposed above and rearward of the spring receiving portion 43 of the first mounting member 40 so as to face the spring receiving portion 43.

[0057] The second oscillating shaft 70 is for supporting the second mounting member 60 so that it can oscillate. The second oscillating shaft 70 is formed in a generally cylindrical shape with its axis oriented in the left-right direction. The second oscillating shaft 70 is inserted through a pair of left and right extending portions 14d (through holes 14e) of the connecting member 14 and the first cylindrical portion 61 of the second mounting member 60. This allows the second mounting member 60 to be connected to the steering handle 11 via the second oscillating shaft 70. The second mounting member 60 can oscillate relative to the steering handle 11 around the second oscillating shaft 70.

[0058] The spring 80 is for biasing the steering handle 11 upward. The spring 80 is constituted by a compression coil spring. The spring 80 is fitted into the extension portion 42 of the first mounting member 40, and is disposed with its axial direction facing the axial direction of the extension portion 42 (rearward and upward). The spring 80 can expand and contract along the axial direction of the extension portion 42. The spring 80 is provided in a compressed state between the spring receiving portion 43 of the first mounting member 40 and the spring receiving portion 63 of the second mounting member 60.

[0059] As a result, the spring 80 is attached (connected) to the connecting member 14 and the handle frame 31 so that a biasing force acts on the connecting member 14 and the handle frame 31. Since the handle frame 31 is fixed to the aircraft body, the spring 80 can bias the steering handle 11 rearward and upward via the second mounting member 60. The spring 80 is also disposed in the left-right center of the steering handle 11. More specifically, the spring 80 is disposed so that the distance to the first extension portion 12b on the left side is equal to the distance to the first extension portion 12b on the right side (see FIG. 4).

[0060] Note that the spring 80 may be arranged in a direction different from that of this embodiment (a direction inclining upward toward the rear) as long as it can bias the steering handle 11 upward. For example, the spring 80 may be arranged in a direction inclining downward toward the rear.

[0061] A procedure for adjusting the vertical position of the steering handle 11 using the handle position adjustment mechanism 20 will be described below with reference to FIGS.

[0062] First, the operator grasps the vertical adjustment lever 15 shown in Fig. 8 to release the engagement between the engagement pin 32 and the hole 31d. This allows the operation handle 11 to swing vertically relative to the transmission case 7.

[0063] In this embodiment, since the steering handle 11 is biased upward by the spring 80, when the engagement between the engagement pin 32 and the hole 31d is released, the steering handle 11 can be supported by the spring 80. This makes it possible to prevent the steering handle 11 from swinging downward unintentionally by the operator due to the effect of the steering handle 11's own weight.

[0064] With the engagement between the engagement pin 32 and the hole 31d released, the operator lifts and lowers the control handle 11 to swing the control handle 11 up and down relative to the transmission case 7.

[0065] In this embodiment, the steering handle 11 is biased upward by the spring 80, so that the operator can lift the steering handle 11 with a light force and easily swing the steering handle 11 upward. In this way, in this embodiment, the spring 80 can assist the upward swing of the steering handle 11.

[0066] In this embodiment, the operator must swing the steering handle 11 downward against the biasing force of the spring 80. In this embodiment, the spring 80 is provided so as to bias the steering handle 11 in a rearward and upward direction. The biasing direction of the spring 80 is a direction inclined with respect to the circumferential direction centered on the swing shaft 13. More specifically, as shown in FIG. 9, the biasing direction (expansion direction) of the spring 80 is in a direction inclined with respect to a tangent L2 at an intersection P between an imaginary line L1 along the circumferential direction centered on the swing shaft 13 and the handle body 12. In other words, the biasing direction (expansion direction) of the spring 80 is arranged so as not to coincide with the swing direction of the handle body 12.

[0067] With this configuration, it is possible to prevent the spring 80 from providing excessive resistance to the steering handle 11 when the steering handle 11 is swung downward, thereby preventing a decrease in operability.

[0068] After swinging the steering handle 11 shown in Fig. 8 up and down, the operator releases the up-down adjustment lever 15 at a predetermined swing position. This causes the engagement pin 32 to engage with the hole 31d, and the steering handle 11 is fixed at the predetermined swing position. In this way, the operator can adjust the up-down position of the steering handle 11.

[0069] Here, in this embodiment, since the engine 4 is disposed at the front of the machine body, there is a concern that when an operator lifts the steering handle 11 during the above-mentioned adjustment of the vertical position, the machine body may tilt forward to follow the steering handle 11. In this embodiment, the upward swing of the steering handle 11 is assisted by the spring 80, and the biasing force of the spring 80 acts on the transmission case 7 via the first mounting member 40 and the handle frame 31 (see FIG. 7), thereby preventing the machine body from tilting forward. As a result, the steering handle 11 can be swung upward without previously tilting the machine body forward (without causing the front end of the machine body to contact the ground), and the task of swinging the steering handle 11 upward can be easily performed.

[0070] In addition, by orienting the axis of the spring 80 in the upward and rearward direction, the orientation of the spring 80 can be made closer to the orientation of the steering handle 11, making the spring 80 less noticeable and improving the aesthetic appearance. In addition, the installation space for the steering handle 11 and the spring 80 can be prevented from increasing, making the device more compact.

[0071] The spring 80 is provided in the lateral center of the steering handle 11 (see FIG. 4). This allows the upward swing of the steering handle 11 to be assisted in a balanced manner (without leaning to the left or right side of the steering handle 11). It also prevents the multiple cables C arranged on both the left and right sides of the steering handle 11 from interfering with the spring 80.

[0072] As described above, the walk-behind working machine 1 according to this embodiment is equipped with a steering handle 11 (handle) that can swing up and down, and a handle position adjustment mechanism 20 that can adjust the up and down position of the steering handle 11, and the handle position adjustment mechanism 20 is equipped with a regulating mechanism 30 that can regulate the swing of the steering handle 11, and a spring 80 (biasing member) that urges the steering handle 11 upward.

[0073] With this configuration, the operability when adjusting the vertical position of the steering handle 11 can be improved.

[0074] The spring 80 applies a biasing force to the steering handle 11 in a direction inclined with respect to the circumferential direction about the pivot point (pivot shaft 13) of the steering handle 11 (see FIG. 9).

[0075] With this configuration, it is possible to prevent the spring 80 from exerting an excessively large biasing force on the steering handle 11.

[0076] The spring 80 is made of a compression coil spring, and is disposed so that the direction of expansion and contraction is inclined upward toward the rear (see FIG. 7).

[0077] With this configuration, the spring 80 is arranged so as to follow the orientation of a typical steering wheel 11, thereby making the arrangement more compact and improving the design.

[0078] The spring 80 is disposed in the center of the left-right width of the operation handle 11 (see FIG. 4).

[0079] With this configuration, it is possible to apply a biasing force to the steering handle 11 without any bias to the left or right.

[0080] In addition, the steering handle 11 has a handle body 12 that is swingably connected to both the left and right side surfaces of the transmission case 7, and one end (upper end) of the spring 80 is connected to a connecting member 14 that connects the left part (first extension portion 12b on the left side) and the right part (first extension portion 12b on the right side) of the handle body 12 (see Figure 7).

[0081] By configuring in this manner, the spring 80 can be connected to the control handle 11 with a simple configuration.

[0082] In addition, the regulating mechanism 30 includes an engagement pin 32 (first regulating member) that can swing integrally with the steering handle 11, and a handle frame 31 (second regulating member) that is fixed to the transmission case 7 and can engage with the engagement pin 32, and one end (lower end) of the spring 80 is connected to the handle frame 31 (see Figure 7).

[0083] By configuring in this manner, the spring 80 can be connected to the aircraft body with a simple configuration.

[0084] The control handle 11 according to this embodiment is one embodiment of the handle according to the present invention. The engagement pin 32 according to this embodiment is one embodiment of a first stop member according to the present invention. Moreover, the spring 80 according to this embodiment is one embodiment of the biasing member according to the present invention. Moreover, the handle frame 31 according to this embodiment is one embodiment of the second stop member according to the present invention.

[0085] Although the embodiment of the present invention 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.

[0086] For example, the walk-behind working machine 1 in this embodiment is a walk-behind management machine for leveling the ground, etc., but the type of walk-behind working machine 1 is not limited to this and may be a walk-behind harvester, a walk-behind grass cutter, etc.

[0087] In addition, the spring 80 is configured to bias the steering handle 11 in an upward and rearward direction, but as long as the spring 80 can bias the steering handle 11 in an upward direction, it is also possible to bias the steering handle 11 in a direction other than upward and rearward. For example, the spring 80 can bias the steering handle 11 in a vertically upward direction.

[0088] Furthermore, the spring 80 is a compression coil spring, but there is no particular limitation on the type of the spring 80. For example, the spring 80 may be a torsion coil spring or the like.

[0089] In addition, the upper end of the spring 80 is attached to the connecting member 14 via the second attachment member 60, but it may be attached to a member other than the connecting member 14. In addition, the lower end of the spring 80 is attached to the handle frame 31 via the first attachment member 40, but it may be attached to a member other than the handle frame 31.

[0090] As shown in FIG. 4, only one spring 80 in this embodiment is arranged in the left-right center of the steering handle 11. FIG. 10(a) is a schematic diagram of the spring 80 and the steering handle 11 in this embodiment. The number and arrangement of the springs 80 are not limited to this embodiment and can be changed as desired. For example, as shown in FIG. 10(b) as a schematic diagram, the springs 80 may be arranged in a plurality of springs on the connecting member 14 (in FIG. 10(b), a pair of springs on the left and right sides of the left-right center of the vehicle body). Alternatively, the springs 80 can be arranged only on the right side or only on the left side of the vehicle body. In this manner, any number of springs 80 can be arranged at any position.

[0091] In addition, the regulating mechanism 30 is configured to engage the engaging pin 32 with the hole portion 31d of the handle frame 31, but the specific structure of the regulating mechanism 30 is not limited as long as it is capable of regulating the swinging of the steering handle 11.

[0092] Although the handle body 12 is directly attached to the transmission case 7 (see FIG. 3), the method of attaching the handle body 12 to the transmission case 7 is not particularly limited. For example, the handle body 12 may be indirectly attached to the transmission case 7 via a predetermined member (e.g., a handle frame 31, etc.). [Explanation of symbols]

[0093] 1 Walk-behind work machine 11 Steering wheel 20 Position adjustment mechanism 30 Regulatory Mechanisms 80 Spring

Claims

1. A handle that can be swung up and down; a handle position adjustment mechanism capable of adjusting the vertical position of the handle; A walk-behind working machine comprising: The handle position adjustment mechanism includes: A restricting mechanism capable of restricting the swinging of the handle; A biasing member that biases the handle upward; Equipped with Walk-behind work machine.

2. The biasing member is A biasing force is applied to the handle in a direction inclined with respect to a circumferential direction about a pivot point of the handle. The walk-behind work machine according to claim 1.

3. The biasing member is It is composed of a compression coil spring and is arranged so that the expansion and contraction direction is inclined upward toward the rear. The walk-behind work machine according to claim 1.

4. The biasing member is Located in the center of the left and right width of the handle, The walk-behind work machine according to claim 1.

5. The handle is The handle body is pivotally connected to both the left and right sides of the transmission case, The biasing member is One end is connected to a connecting member that connects the left and right parts of the handle body. The walk-behind work machine according to claim 1.

6. The regulating mechanism is A first stop member that is swingable integrally with the handle; a second stop member fixed to a transmission case and engageable with the first stop member; Equipped with The biasing member is One end is connected to the second stop member. The walk-behind working machine according to any one of claims 1 to 5.

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