JP5486517B2 - Construction machinery steering device - Google Patents

Description

  The present invention relates to a steering device for a construction machine configured to perform steering by operating a handle, such as a wheel loader or a wheeled hydraulic excavator.

  In general, a wheel-type construction machine known as a wheel loader or a wheel-type hydraulic excavator is equipped with a steering device that steers a steering column disposed on the front side of a driver's seat from a handle. A steering device for a construction machine according to this type of prior art is provided with a mechanism for tilting the steering column forward and backward so that the handle does not get in the way when an operator gets on and off the driver's seat.

  This mechanism is called a tilt angle adjustment mechanism, for example, and adjusts the tilt angle of the steering column by tilting the steering column in a direction approaching the driver's seat and a direction away from the driver's seat. In addition, there is also provided a column length adjusting mechanism for adjusting the column length of the steering column in the upward and downward directions. An operator seated in the driver's seat can adjust the position of the handle variably according to preference by manually operating the tilt angle adjustment mechanism and the column length adjustment mechanism (for example, Patent Documents 1 and 2). reference).

JP 2003-27524 A JP 2007-120220 A

  Incidentally, the above-described steering device according to the prior art only includes a tilt angle adjustment mechanism that adjusts the tilt angle of the steering column and a column length adjustment mechanism that adjusts the column length. There is still room for improvement.

  That is, since the steering wheel gets in the way when the operator gets in and out of the driver's seat, the steering column is moved to a jumping position away from the driver's seat, and when the operator is seated in the driver's seat, the steering column is close to the driver's seat together with the handle. An operation to return to the driving position is performed. However, in the case of the prior art, the operator may need to perform the tilt angle adjustment operation and the column length adjustment operation each time when the steering column is returned to the driving position. There is a problem that workability cannot be improved.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to allow the steering column to be moved between a driving position and a jumping position by a simple operation and to easily get on and off the driver's seat. It is an object of the present invention to provide a steering device for a construction machine that can be performed in the same manner.

  In order to solve the above-described problem, a steering device for a construction machine according to a first aspect of the present invention includes a steering column disposed on the front side of a driver's seat of the construction machine and steered by a handle, and the steering column is close to the driver's seat. A steering mechanism that jumps up to a driving position away from the driver's seat, and the steering column has a lower end that is fixed to the floor side of the driver's seat and extends upward and downward A column and an upper column provided on the upper side of the lower column and jumped up by the jumping mechanism with respect to the lower column, the jumping mechanism between the lower column and the upper column A jumping member extending in the upward and downward direction and having a middle portion in the length direction rotatably attached to the lower column and an upper side fixed to the upper column, and the lower A lock pin that is displaceably disposed on the side of the frame and that normally engages the jumping member to position the upper column at the operating position, and is provided between the jumping member and the lower column. When the lock pin is disengaged, the upper column is constituted by a spring member that jumps up together with the jumping member.

  According to a second aspect of the present invention, an urging member for constantly urging the lock pin toward the jumping member is provided between the lower column and the lock pin.

  According to a third aspect of the present invention, the jumping member is provided with an engagement hole for engaging the lock pin, and the lock pin is formed in a tapered shape at a portion engaged with the engagement hole. It is said.

  On the other hand, according to a fourth aspect of the present invention, the jumping mechanism includes a pedal that is provided on the lower column side and is rotated by an operator seated on the driver's seat. Until the operation, it is engaged with the jumping member, and when the pedal is operated, the engagement with the jumping member is released.

  According to a fifth aspect of the present invention, the lower column is provided with a pin holding body that opposes the flip-up member in the upward and downward directions and holds the lock pin so as to be displaceable. The pin holding body and the lock A biasing member that constantly biases the lock pin toward the jumping member is provided between the pins.

  According to a sixth aspect of the present invention, the pin holding body is provided with a pin operating member that displaces the lock pin upward and downward against the biasing member, and the pin operating member The front end side of the pedal is connected to the base end side of the pedal that is depressed by the operator seated on the seat.

  As described above, according to the first aspect of the present invention, while the lock pin is engaged with the flip-up member rotatably attached to the lower column, the upper column is moved to the driving position close to the driver's seat. In this state, the operator can easily perform a steering operation using the steering wheel. On the other hand, when the handle gets in the way when the operator stands up and leaves the driver's seat, the spring member jumps up the upper column together with the jumping member by releasing the engagement of the lock pin with the jumping member. And the handle can be moved to a jumping position away from the driver's seat. Therefore, it is possible for the operator to jump the steering column together with the steering wheel in a direction away from the driver's seat only by operating the jumping mechanism, and the workability when getting on and off can be greatly improved.

  According to the invention of claim 2, the lock pin can be biased toward the jumping member by the biasing member, and the jumping operation of the jumping member is regulated by the lock pin to lock the upper column in the operating position. Can continue.

  In the invention of claim 3, by forming the engagement portion of the lock pin in a tapered shape, the lock pin can be smoothly engaged and released from the engagement hole of the jumping member, and the upper column is The operability when tilting to the driving position and the jumping position can be improved.

  On the other hand, according to the invention of claim 4, when the operator seated in the driver's seat operates the pedal, the engagement of the lock pin with the jumping member can be easily released, and accordingly the upper column is operated. The spring member can jump up immediately from the position to the jumping position.

  According to the invention of claim 5, the lock pin can be held displaceably at a position facing the flip-up member in the upward and downward directions by the pin holder provided in the lower column. A biasing member that constantly biases the lock pin toward the jumping member can be provided between the pin holder and the lock pin.

  Furthermore, in the invention of claim 6, the pin operating member provided in the pin holding body is rotated by a pedal operation to displace the lock pin upward and downward against the biasing member in the pin holding body. The lock pin can be engaged with and released from the engagement hole of the jumping member by the pin operation member.

It is a front view which shows the wheel loader by which the steering device by embodiment of this invention was mounted. It is a perspective view which expands and shows the steering apparatus in FIG. FIG. 3 is a front view of the steering device shown in FIG. 2. FIG. 4 is a left side view of the steering device shown in FIG. 3. It is sectional drawing which expanded the tilt lever of the steering apparatus, the raising member, etc. from the arrow VV direction in FIG. FIG. 5 is a cross-sectional view of a steering device jumping mechanism, tilt angle adjusting mechanism, column length adjusting mechanism, and the like that are enlarged from the direction of arrows VI-VI in FIG. 4. It is sectional drawing in the same position as FIG. 6 which shows the state which jumped up the upper column with the jumping member by the jumping mechanism. FIG. 3 is an exploded perspective view showing an upper column, a lower column, a jumping mechanism, a tilt angle adjusting mechanism, a column length adjusting mechanism, and the like of the steering device. FIG. 9 is an exploded perspective view showing a state where the swing plate and the bending plate in FIG. 8 are assembled as a lifting member. It is a disassembled perspective view which shows the lower column of a steering apparatus, a raising mechanism, etc.

  Hereinafter, a case where a steering device for a construction machine according to an embodiment of the present invention is applied to a wheel loader will be described as an example and described in detail with reference to the accompanying drawings.

  Here, FIG. 1 to FIG. 10 show an embodiment of the present invention. In the figure, reference numeral 1 denotes a wheel loader as a construction machine employed in the present embodiment. The wheel loader 1 has a vehicle body 2 that can be self-propelled by a front wheel 5 and a rear wheel 6 described later. The vehicle body 2 of the wheel loader 1 includes a rear vehicle body 3 and a front vehicle body 4 connected to the front side of the rear vehicle body 3. When steering the wheel loader 1, the front vehicle body 4 is swung left and right with respect to the rear vehicle body 3, thereby steering the traveling direction.

  The front vehicle body 4 is provided with left and right front wheels 5, and the rear vehicle body 3 is provided with left and right rear wheels 6. These front wheels 5 and rear wheels 6 constitute the wheels of the wheel loader 1 and are driven by four wheels by a traveling hydraulic motor (not shown) using a hydraulic closed circuit (HST), for example. The wheel loader 1 as the construction machine employed in the present invention is not limited to four-wheel drive, and may be a vehicle configured to drive only the front wheels 5 or the rear wheels 6, for example.

  Reference numeral 7 denotes a working device provided on the front side of the vehicle body 2, and the working device 7 is attached to the front vehicle body 4 so as to be able to move up and down, and is attached to the tip side of the boom 7 A so as to be rotatable. Loader bucket 7B, a pair of left and right boom cylinders (not shown) that drive the boom 7A up and down, and a bucket cylinder 7C that rotates the loader bucket 7B up and down. Yes. The working device 7 performs, for example, excavation work of earth and sand, scooping work, and the like using the loader bucket 7B.

  Reference numeral 8 denotes a floor board provided on the front side of the rear vehicle body 3, and the floor board 8 constitutes a floor surface on which the driver's seat 9 is installed. A canopy 10 that covers the driver's seat 9 from above is provided above the floor board 8. Further, on the upper surface side of the floor board 8, a steering device 11 described later is provided on the front side of the driver's seat 9, and a travel pedal and an operation lever (both not shown) are provided.

  An operator seated in the driver's seat 9 controls a traveling direction of the vehicle body 2 by steering a handle 12 described later to swing the front vehicle body 4 leftward and rightward. The operator operates the work device 7 by operating the operation lever. In addition, on the rear side of the rear vehicle body 3, an engine serving as a prime mover of the wheel loader 1 is mounted together with a hydraulic pump (none of which is shown).

  Reference numeral 11 denotes a steering device employed in the present embodiment. The steering device 11 includes a steering column 13 (to be described later) that is steered by a handle 12, a jumping mechanism 25, a tilt angle adjusting mechanism 33, and a column length adjusting mechanism 37. It is comprised including.

  A steering column 13 is located on the floor board 8 and is disposed on the front side of the driver's seat 9. As shown in FIGS. 2 to 10, the steering column 13 includes a lower column 14 whose lower end is fixed to the floor plate 8 on the front side of the driver's seat 9, and front, rear and upper sides on the upper side of the lower column 14. , And an upper column 16 (described later) attached to be movable in the downward direction. The steering column 13 is swung in a solid line in FIG. 3 when the upper column 16 is swung in the front and rear directions of the vehicle with respect to the lower column 14 (in the directions of arrows A and B in FIGS. 2 and 3). It is tilted between the operation position shown and the jumping position shown by the two-dot chain line.

  As shown in FIGS. 2 to 4, the lower column 14 has an installation plate 14 </ b> A that is detachably installed on the floor plate 8 on the lower end side. The lower column 14 constitutes a fixed stand erected on the floor board 8 via an installation board 14A on the lower end side. On the upper end side of the lower column 14, a pair of left and right shaft support portions 14B made of a cylindrical bush is provided. The upper column 16 is connected to each of the shaft support portions 14B via support members 31 and 32, which will be described later, via a jumping member 26 so as to be able to rotate in the front and rear directions of the vehicle.

  The lower column 14 is provided with a notch hole 14C located below the shaft support part 14B, and a not-shown spring 47, which will be described later, is inserted into the notch hole 14C as shown in FIG. The Further, in order to avoid contact and interference between a lower shaft 15 (described later) housed in the lower column 14 and a spring 47, the notch hole 14C is formed on one side of the left column and the right side of the lower column 14 (for example, , On the left side).

  A lower shaft 15 is rotatably provided in the lower column 14, and the lower shaft 15 transmits a steering operation of the handle 12 to a steering cylinder (not shown) formed of a hydraulic cylinder. They are connected via a joint member 22. The steering operation of the handle 12 is transmitted from the upper shaft 21 to the lower shaft 15 via the joint member 22.

  Reference numeral 16 denotes an upper column provided on the upper side of the lower column 14, and the upper column 16 has two operating positions indicated by a solid line in FIG. It is tilted to the jumping position indicated by the dotted line. When a tilt angle adjusting mechanism 33 described later is used, the tilt angle of the upper column 16 with respect to the lower column 14 (that is, the tilt angle in the directions indicated by arrows A and B in FIGS. 2 and 3) is adjusted. When the column length adjusting mechanism 37 described later is used, the height position of the upper column 16 with respect to the lower column 14 is adjusted upward and downward (that is, the column length is adjusted in the direction indicated by the arrow C in FIGS. 2 and 3). The

  For this reason, the upper column 16 includes a lower column frame body 17 and a mounting post 18 mounted on the upper side of the column frame body 17 as shown in FIGS. The upper shaft 21 described later is rotatably accommodated. The column frame 17 is configured as a quadrangular frame by a front plate portion 17A, a rear plate portion 17B, and left and right side plate portions 17C and 17D, and an upper shaft 21 is spaced upward and downward with a gap inside. A space portion 17E to be inserted is formed.

  The left and right side plate portions 17C and 17D are formed as legs that face in the left and right directions across the space portion 17E and extend longer upward and downward than the front plate portion 17A and the rear plate portion 17B. . The left and right side plate portions 17C and 17D are formed with U-shaped slits 17C1 and 17D1 that extend upward and downward and open at the lower ends. The left side plate portion 17C is formed with an I-shaped slit 17C2 spaced above the U-shaped slit 17C1, and the I-shaped slit 17C2 is U-shaped as shown in FIGS. They are arranged on the same straight line as the slit 17C1 with the same slit width.

  A fastening bolt 34 described later is inserted into the I-shaped slit 17C2 of the side plate portion 17C as shown in FIG. 9, and support shafts 31 and 32 described later are inserted into the U-shaped slits 17C1 and 17D1 of the side plate portions 17C and 17D. Are inserted respectively. The U-shaped slit 17C1 and I-shaped slit 17C2 formed in the side plate portion 17C of the column frame body 17 and the U-shaped slit 17D1 formed in the side plate portion 17D are a length adjusting portion of a column length adjusting mechanism 37 described later. It constitutes.

  On the lower end side of the mounting post 18, a fixing plate 18 </ b> A is provided to hang downward, and this fixing plate 18 </ b> A is fixed to the front plate portion 17 </ b> A of the column frame 17 using a plurality of bolts 19. Thereby, the mounting post 18 is integrated in a state of being mounted on the upper side of the column frame body 17. Further, as shown in FIG. 5, an upper shaft 21 is rotatably mounted inside the mounting post 18 via a bearing 20. On the other hand, as shown in FIGS. 2 to 4, 8, and 9, a cylindrical cap 18 </ b> B that seals between the mounting shaft 18 and the upper shaft 21 described later is detachably provided on the upper end side of the mounting post 18.

  Reference numeral 21 denotes a steering upper shaft that constitutes a part of the upper column 16, and the upper shaft 21 is inserted into the space 17E of the column frame 17 from below, and moves upward and downward in the mounting post 18. It is arranged through. The upper end side of the upper shaft 21 is a protruding portion 21A that protrudes upward from the mounting post 18, and the handle 12 is attached to the protruding portion 21A (see FIG. 2). Further, as shown in FIG. 5, a fitting hole 21B is formed in the axial direction on the lower end side of the upper shaft 21, and a shaft portion 22B of a joint member 22 described later is rotated by a serration 22C in the fitting hole 21B. It is inserted in a stopped state.

  Reference numeral 22 denotes a joint member provided between the lower shaft 15 and the upper shaft 21. The joint member 22 includes a joint portion 22A attached to the upper end side of the lower shaft 15 and the joint portion 22A as shown in FIG. On the other hand, the shaft portion 22B is connected to the front, rear, left and right so as to be swingable and extends upward. The joint member 22 is configured by a universal joint that transmits the rotation of the shaft portion 22B to the lower shaft 15 via the joint portion 22A.

  The joint member 22 is formed with a serration 22C having a predetermined length on the upper side of the shaft portion 22B. The serration 22C restricts relative rotation between the fitting hole 21B of the upper shaft 21 and the shaft portion 22B of the joint member 22, and allows relative displacement in the axial direction. When the height position of the upper column 16 with respect to the lower column 14 is adjusted in the direction of arrow C in FIG. 5 by a column length adjusting mechanism 37 described later, the upper shaft 21 is displaced relative to the shaft portion 22B in the axial direction. Can be compensated by the serration 22C.

  Reference numeral 23 denotes a lever support attached to the side plate portion 17C of the column frame 17, and the lever support 23 has a substantially rectangular support plate 23A suspended downward. A cylindrical nut 24 is attached via a fastening bolt 34. The cylindrical nut 24 constitutes a fastening member together with the fastening bolt 34, and a tilt lever 35 described later is fixed to the distal end side of the cylindrical nut 24. When the operator rotates the tilt lever 35, the cylindrical nut 24 is rotated relative to the fastening bolt 34, and the cylindrical nut 24 and the fastening bolt 34 are fastened and released.

  Reference numeral 25 denotes a jumping mechanism employed in the present embodiment. The jumping mechanism 25 is provided to extend upward and downward between the lower column 14 and the upper column 16, and the upper column 16 is connected to the lower column 14. A jumping member 26 that jumps up, a pin holder 38, a lock pin 40, a lock spring 41, a pin operating member 42, a pedal 44, and a jumping spring 47, which will be described later, are configured.

  The flip-up member 26 extends between the side plate portion 17C of the column frame 17 and the lever support member 23, extends in the downward direction, and has a flat plate-like swing plate 27 into which the lower end is inserted into the lower column 14, and the swing member 26. A bending plate 29 fixed to the moving plate 27 with a plurality of bolts 28, and provided on the lower end side of the swinging plate 27, facing a pin holding body 38 and a lock pin 40, which will be described later, upward and downward in the lower column 14. And a cam plate 30 to be configured.

  The swinging plate 27 extending in the upward and downward directions is provided with a pivoting portion 27A at an intermediate portion in the length direction, and the pivoting portion 27A is connected to a shaft support portion 14B of the lower column 14 via a support shaft 31 described later. Can be pivoted. In addition, the swing plate 27 is provided with a tilt hole adjusting long hole portion 27B at a position above the pivot mounting portion 27A. The long hole portion 27B is centered on the pivot mounting portion 27A. It is formed as a long hole extending in an arc shape in the front and rear directions.

  The upper side of the swing plate 27 (the peripheral portion of the long hole portion 27B) is fastened to the column frame 17 of the upper column 16 until the state where the cylindrical nut 24 and the fastening bolt 34 are released by the tilt lever 35 described later. It is in a state of being fixed via the bolt 34, and the entire jumping member 26 is fixed to the upper column 16. On the other hand, on the lower side of the swing plate 27, a pair of protrusions 27C are provided on the front surface side and the back surface side so as to protrude in the left and right directions. 47 is hooked.

  The bent plate 29 has left and right bent portions 29A and 29B as shown in FIGS. 8 and 9, and the left bent portion 29A has a pivoting portion 27A and a long hole portion 27B of the swing plate 27. Are fixed by bolts 28 between them. The right bent portion 29B is provided with another pivot portion 29C at a position facing the pivot portion 27A of the swing plate 27 in the left and right directions. The pivot portion 29C is a shaft of the lower column 14. The support portion 14B is rotatably attached via a support shaft 32 described later.

  The jumping member 26 is disposed so as to sandwich the side plate portions 17C and 17D of the column frame body 17 from the left and right directions between the swinging plate 27 and the bent portion 29B of the bent plate 29. In this state, the pivot portions 27A and 29C of the jumping member 26 are connected to the U-shaped slits 17C1 and 17D1 of the column frame 17 and the shaft support portions 14B of the lower column 14 by the support shafts 31 and 32. (See FIG. 5).

  Here, the support shafts 31 and 32 constitute the rotation fulcrum of the jumping mechanism 25 and are arranged at the same height position facing each other in the left and right directions. The support shaft 31 is inserted into the U-shaped slit 17C1 of the column frame 17, the pivoting portion 27A of the swing plate 27, and the shaft support portion 14B on the left side of the lower column 14, and the distal end side protruding from the shaft support portion 14B. A nut 31 </ b> A is screwed onto the screw. The support shaft 32 is inserted into the U-shaped slit 17D1 of the column frame 17, the pivoting portion 29C of the folding plate 29, and the right shaft support portion 14B of the lower column 14, and protrudes from the shaft support portion 14B. A nut 32A is screwed to the distal end side.

  The cam plate 30 provided on the lower end side of the swing plate 27 is provided with a tapered engagement hole 30A as shown in FIGS. 6 and 7, and a lock pin 40 described later is formed in the engagement hole 30A. The taper portion 40A is engaged so as to be able to advance and retreat. An inclined surface 30 </ b> B is formed on the lower surface side of the cam plate 30. The inclined surface 30B smoothly guides the distal end surface of the lock pin 40 described later from the disengagement position shown in FIG. 7 to the engagement position shown in FIG.

  Reference numeral 33 denotes a tilt angle adjusting mechanism employed in the present embodiment. The tilt angle adjusting mechanism 33 is provided with a long hole portion 27B for adjusting a tilt angle formed in the swing plate 27, and the long hole portion 27B. A fastening bolt 34 that fastens the column frame 17 of the upper column 16 to the lever support 23 and maintains the tilt angle adjustment position, and a manual release that releases the fastening state of the fastening bolt 34 from the outside. It includes a tilt lever 35 as a lever.

  The fastening bolt 34 constitutes the fastening member of the tilt angle adjusting mechanism 33 together with the cylindrical nut 24. The tilt lever 35 is fixed to the distal end side of the cylindrical nut 24 using a bolt 35 </ b> A, and rotates the cylindrical nut 24 in the forward and reverse directions with respect to the fastening bolt 34. Thereby, the cylindrical nut 24 is selectively rotated in the fastening direction and the loosening direction with respect to the fastening bolt 34.

  As shown in FIG. 8, the fastening bolt 34 has a pair of chamfered portions 34 </ b> A formed on the base end side, and each chamfered portion 34 </ b> A is engaged with the I-shaped slit 17 </ b> C <b> 2 of the column frame 17. As a result, the fastening bolt 34 is attached to the side plate portion 17C of the column frame 17 in a non-rotating state. The front end side of the fastening bolt 34 is inserted into the elongated hole portion 27B of the swing plate 27 through the washer 36, and is screwed onto the cylindrical nut 24 from the back surface side of the support plate 23A. The fastening bolt 34 sandwiches the periphery of the long hole portion 27B of the swing plate 27 between the side plate portion 17C of the column frame body 17 and the support plate 23A, so that the column frame body 17 of the upper column 16 is lifted up. Fastened to the rocking plate 27.

  However, when the operator rotates the tilt lever 35 upward, the cylindrical nut 24 is rotated in the loosening direction with respect to the fastening bolt 34, and the fastening state to the swing plate 27 by the fastening bolt 34 and the cylindrical nut 24 is achieved. Is released. For this reason, the column frame 17 of the upper column 16 can be moved relative to the lower column 14 along the elongated hole 27B of the swing plate 27 together with the lever support 23 and the fastening bolt 34. 16 tilt angles can be adjusted forward and backward. At this time, the upper column 16 is tilted around the support shafts 31 and 32 with respect to the lower column 14, and the tilt angle is adjusted within the arc range of the long hole portion 27B.

  Reference numeral 37 denotes a column length adjusting mechanism employed in the present embodiment. The column length adjusting mechanism 37 is a U-shaped slit 17C1 as a length adjusting portion formed in the side plate portions 17C and 17D of the column frame 17. 17D1, an I-shaped slit 17C2, a cylindrical nut 24, a fastening bolt 34, and a tilt lever 35. The column length adjusting mechanism 37 sets the height position of the upper column 16 with respect to the lower column 14 to the U-shaped slits 17C1, 17D1, when the fastening state between the cylindrical nut 24 and the fastening bolt 34 is released by the tilt lever 35. It is possible to adjust in the upward and downward directions along the length direction with the I-shaped slit 17C2, that is, in the direction indicated by the arrow C in FIGS.

  Reference numeral 38 denotes a pin holder fixed to the lower column 14 with a plurality of bolts 39. The pin holder 38 is formed in a hollow box shape as shown in FIG. Shaped pin guides 38A and 38B are provided (see FIGS. 6 and 7). A lock pin 40 (described later) is held on the pin holder 38 so as to be slidable and displaceable between the pin guides 38A and 38B. Further, the pin holder 38 is provided with a mounting cylinder portion 38C at a position on the rear side of the lower column 14 with respect to the pin guides 38A and 38B. The mounting cylinder portion 38C has a bar mounting portion of a pedal 44 described later. 44B is inserted.

  Here, as shown in FIG. 4, the pin holder 38 is positioned below the swing plate 27, and is located on one side (for example, the left side when viewed from the rear side of the vehicle) of the left and right sides of the lower column 14. They are arranged side by side. That is, the pin holder 38 is fixedly provided in the lower column 14 at a position radially outside the lower shaft 15 in order to avoid contact and interference with the lower shaft 15 accommodated in the lower column 14. It has been.

  Reference numeral 40 denotes a tapered lock pin constituting a part of the jumping mechanism 25, and the lock pin 40 is slid into the pin holding body 38 via pin guides 38A and 38B as shown in FIGS. It is provided to be movable. One side in the length direction of the lock pin 40 is formed as a tapered taper portion 40A, and the taper portion 40A side is slidably supported by a pin guide 38A. The other side in the length direction of the lock pin 40 is formed as a parallel pin having the same outer diameter, and is slidably supported by a pin guide 38B.

  At the intermediate portion in the length direction of the lock pin 40, an annular spring receiving portion 40B formed larger in diameter than the inner diameter of the pin guides 38A, 38B, and projecting radially outward from the outer peripheral surface of the spring receiving portion 40B. And a pair of protruding portions 40C. The pair of protrusions 40C are disposed at positions facing each other in the radial direction of the spring receiving portion 40B. Each of the gripping portions 42A of the pin operation member 42 described later is detachably engaged with the pair of protruding portions 40C so as to be sandwiched from above and below.

  In the pin holding body 38, a lock spring 41 is provided as an urging member located on the outer peripheral side of the lock pin 40. The lock spring 41 is formed between the spring receiving portion 40B of the lock pin 40 and the pin guide 38B. It is arranged in between. The lock spring 41 constantly urges the taper portion 40A of the lock pin 40 in a direction protruding outward from the pin guide 38A. As a result, the taper portion 40A of the lock pin 40 is engaged with the engagement hole 30A of the cam plate 30 so as to advance and retreat, as shown in FIGS.

  As shown in FIG. 6, while the tapered portion 40 </ b> A of the lock pin 40 is engaged with the engagement hole 30 </ b> A of the cam plate 30, the swing plate 27 of the jumping member 26 is the pin holder 38 and the lock pin 40. It is locked to the lower column 14 via As a result, the upper column 16 is held in a state of being positioned at the operation position indicated by the solid line in FIG. On the other hand, as shown in FIG. 7, when the taper portion 40A of the lock pin 40 is disengaged from the engagement hole 30A of the cam plate 30, the swinging plate 27 of the jumping member 26 is moved in FIG. It is rotated in the direction of arrow A. As a result, the upper column 16 is jumped up to the lower column 14 at a jumping position indicated by a two-dot chain line in FIG.

  Reference numeral 42 denotes a pin operation member that operates the lock pin 40 against the lock spring 41. The pin operation member 42 is formed to be separated from the outer diameter of the spring receiving portion 40B of the lock pin 40 in the left and right directions. A pair of gripping portions 42A. Each gripping part 42A grips each protrusion 40C of the lock pin 40 so as to be sandwiched from above and below. Further, the pin operating member 42 is connected and fixed to a bar mounting portion 44B of a pedal 44 described later using a bolt 43 while being inserted into the pin holding body 38 from the rear. As a result, the pin operating member 42 is assembled in the pin holding body 38 so as to rotate up and down around the position of the mounting cylinder portion 38C.

  44 is a pedal for stepping on the jumping mechanism 25. The pedal 44 is formed by bending a pedal bar 44A as shown in FIG. 10, and a pin holding body 38 provided on the base end side of the pedal bar 44A. This is comprised of a bar mounting portion 44B that is rotatably fitted in the mounting cylinder portion 38C, and a foot plate 44C that is provided on the front end side of the pedal bar 44A and is stepped on by the operator.

  As shown in FIGS. 2 and 3, the pedal bar 44 </ b> A of the pedal 44 extends so as to obliquely cross the left side of the lower column 14 from the position of the pin holder 38, and the footboard 44 </ b> C is seated in the driver's seat 9. It is arranged at a position near the feet of the operator. When the operator steps on the pedal 44, the pin operating member 42 is rotated around the position of the mounting cylinder portion 38C in the pin holding body 38. As a result, the pin operating member 42 pushes the protrusions 40C of the lock pin 40 downward by the gripping portions 42A, and the lock pin 40 resists the lock spring 41 from the engagement position shown in FIG. To the disengagement position shown in FIG. Thereby, the engagement state of the lock pin 40 with respect to the engagement hole 30A of the cam plate 30 is released.

  On the other hand, when the stepping operation of the pedal 44 is released, the lock pin 40 is urged upward along the pin guides 38A and 38B by the lock spring 41. For this reason, when the operator pulls the handle 12 toward the driver's seat 9 side, the upper column 16 and the jumping member 26 are moved together with the support shafts 31 and 32 as the center in the direction indicated by the arrow B. As shown in FIG. 6, the taper portion 40 </ b> A of the lock pin 40 is engaged with the engagement hole 30 </ b> A of the cam plate 30.

  A spring receiving member 45 is detachably fixed to the front side of the lower column 14 by a bolt 46. The spring receiving member 45 has a pin portion 45A extending in the left and right directions as shown in FIG. The pin portion 45A is disposed at a position corresponding to the notch hole 14C of the lower column 14. A spring spring 47, which will be described later, is hooked on each pin portion 45A of the spring receiving member 45.

  Reference numeral 47 denotes two jump springs as spring members constituting a part of the jump mechanism 25. Each of the springs 47 has a length direction as shown in FIGS. The other side is latched to each pin portion 45 </ b> A of the spring receiving member 45, and the other side is latched to each projection 27 </ b> C of the swing plate 27. The jump spring 47 biases the swing plate 27 of the lift member 26 that can swing about the support shafts 31 and 32 toward the front side of the lower column 14 in the arrow A direction.

  Here, when the lock pin 40 is moved from the engagement position shown in FIG. 6 to the disengagement position shown in FIG. 7 and the engagement state of the lock pin 40 with respect to the engagement hole 30A of the cam plate 30 is released, the jumping up is performed. The swing plate 27 of the jumping member 26 is urged in the direction of arrow A by the spring 47 and swings. As a result, the upper column 16 is jumped up to the lower column 14 at a jumping position indicated by a two-dot chain line in FIG.

  Reference numeral 48 denotes two cushion members attached to the front side of the lower column 14, and each cushion member 48 is disposed at a position facing the cam plate 30 of the jumping member 26 in the front and rear directions. Dampens a collision with the front side of the lower column 14. That is, when the upper column 16 is raised to the raising position, the cushion member 48 abuts against the cam plate 30 of the raising member 26 and elastically deforms, and in this state, the cushion member 48 is directed in the direction indicated by the arrow A of the swing plate 27. The movement can be restricted.

  The steering device 11 of the wheel loader 1 according to the present embodiment has the above-described configuration. Next, the operation thereof will be described.

  First, when the operator of the wheel loader 1 gets into the driver's seat 9 of the vehicle body 2, the steering column 13 is jumped together with the handle 12 to a jumping position (a position indicated by a two-dot chain line in FIG. 3). For this reason, a relatively large space can be formed between the front side of the driver's seat 9 and the handle 12, and the operator who gets into the driver's seat 9 can be obstructed by the handle 12 on the front side of the driver's seat 9. Can be prevented.

  Next, the operator seated on the driver's seat 9 performs an operation of pulling the handle 12 forward. As a result, the steering column 13 can be moved to the driving position close to the driver's seat 9 in the direction indicated by the arrow B in FIGS. That is, the upper column 16 can be manually tilted with respect to the lower column 14 from the jumping position indicated by a two-dot chain line in FIG. 3 to the operation position indicated by a solid line.

  In this state, when the operator adjusts the tilt angle and column length of the steering column 13 according to his / her physique and preference, the operator operates the tilt lever 35 to rotate upward. Thereby, the cylindrical nut 24 of the tilt angle adjusting mechanism 33 is rotated in the loosening direction with respect to the fastening bolt 34, and the fastening state to the swing plate 27 by the fastening bolt 34 and the cylindrical nut 24 is released.

  Therefore, for example, the operator grips the handle 12 and moves it forward and backward, so that the column frame body 17 of the upper column 16 moves along the elongated hole portion 27B of the swing plate 27 and the lever support body 23 and the fastening bolt 34. And move relative to it. Thus, the tilt angle of the upper column 16 relative to the lower column 14 can be variably adjusted so as to be finely adjusted in the front and rear directions of the vehicle, that is, in the directions indicated by arrows A and B in FIGS.

  At this time, the jumping member 26 including the swing plate 27, the bent plate 29, and the cam plate 30 is fixed to the lower column 14 side via a lock pin 40 (see FIG. 6). For this reason, the upper column 16 can be moved relative to the swing plate 27 of the jumping member 26 within the arc range of the elongated hole portion 27B by the manual operation of the operator, and the support shafts 31, 32 are moved relative to the lower column 14. It can be tilted in the direction of arrows A and B around the center. That is, the adjustment of the tilt angle is performed within the arc range of the long hole portion 27B.

  Further, when adjusting the column length in this state, the operator manually operates the column length adjusting mechanism 37 by gripping the handle 12 and moving it upward and downward. That is, as described above, the upper column 16 is moved upward and downward together with the handle 12 in a state where the fastening state between the cylindrical nut 24 and the fastening bolt 34 is released by the tilt lever 35. Thereby, the height position of the upper column 16 with respect to the lower column 14 is moved upward and downward along the length direction of the U-shaped slits 17C1, 17D1 and the I-shaped slit 17C2, that is, the arrows in FIGS. It can be adjusted in the direction indicated by C, and the column length can be adjusted appropriately.

  Further, the joint member 22 provided between the lower shaft 15 and the upper shaft 21 has a shaft portion 22B coupled to a fitting hole 21B of the upper shaft 21 via a serration 22C as shown in FIG. For this reason, when the column length adjusting mechanism 37 adjusts the height position of the upper column 16 with respect to the lower column 14 in the direction of arrow C in FIG. 5, the upper shaft 21 is pivoted with respect to the shaft portion 22B of the joint member 22. The relative displacement in the direction can be compensated by the serration 22C.

  Next, when the adjustment work as described above is completed, the operator rotates the tilt lever 35 downward, so that the cylindrical nut 24 is rotated together with the tilt lever 35 in the fastening direction of the fastening bolt 34. Thereby, the swinging plate 27 of the jumping member 26 is put into the fastening state again between the fastening bolt 34 and the cylindrical nut 24 together with the support plate 23A. Therefore, the upper column 16 is held at an adjustment position in which the tilt angle and the column length are adjusted with respect to the lower column 14, and this state is fixed. Note that either or both of the tilt angle adjustment and the column length adjustment of the steering column 13 may be selectively performed at the operator's discretion.

  When the operator drives the wheel loader 1 and travels on the road, when the steering wheel 12 is steered, the operating force at this time is transmitted from the upper shaft 21 to the lower shaft 15 via the joint member 22. At this time, the lower shaft 15 transmits the steering operation of the handle 12 to a steering cylinder (not shown) including a hydraulic cylinder. As a result, the wheel loader 1 is swung in the left and right directions with respect to the rear vehicle body 3, and the traveling direction of the wheel loader 1 is steered.

  On the other hand, when the work by the working device 7 of the wheel loader 1 is finished and the operator gets off the driver's seat 9, the handle 12 is positioned near the operator's knee sitting on the driver's seat 9, so that the operator The handle 12 may get in the way when trying to stand up and leave.

  Therefore, when the operator steps on the pedal 44 of the jumping mechanism 25, the engagement state of the lock pin 40 with respect to the cam plate 30 of the jumping member 26 is released, and the swing plate 27 of the jumping member 26 is lifted by the spring 47. Is swung in the direction indicated by the arrow A about the pivot portions 27A and 29C. For this reason, the upper column 16 is tilted around the shaft support portions 14B of the lower column 14 together with the jumping member 26, and the jumping position indicated by a two-dot chain line from the operating position indicated by the solid line in FIG. Automatically jumped to.

  In this case, in the pin holding body 38 provided on the lower column 14 side, the pin operation member 42 is rotated around the position of the mounting cylinder portion 38 </ b> C by the stepping operation of the pedal 44. As a result, the lock pin 40 provided on the pin holding body 38 is moved against the lock spring 41 so as to slide and displace downward with respect to the pin guides 38A and 38B by the respective gripping portions 42A of the pin operation member 42. The

  That is, the lock pin 40 is moved from the engagement position shown in FIG. 6 to the disengagement position shown in FIG. 7 against the lock spring 41, whereby the lock pin 40 is engaged with the engagement hole 30A of the cam plate 30. The state is released. Therefore, the swinging plate 27 of the jumping member 26 is urged in the direction of arrow A in FIG. 7 by the jumping spring 47 about the support shafts 31 and 32, and the upper column 16 is moved with respect to the lower column 14. Thus, it is jumped up to a jumping position indicated by a two-dot chain line in FIG.

  Thus, by raising the upper column 16 in the direction of arrow A with respect to the lower column 14, the operator can stand up and leave the driver's seat 9 without being obstructed by the handle 12. On the other hand, when the stepping operation of the pedal 44 is released, the lock pin 40 is urged upward along the pin guides 38A and 38B by the lock spring 41. At this time, the front end surface of the lock pin 40 is in contact with an inclined surface 30 </ b> B formed on the lower surface side of the cam plate 30.

  Next, when the operator gets into the driver's seat 9 again, the steering column 13 is jumped up to the jumping position together with the handle 12 so that the operator can enter the driver's seat 9 without being disturbed by the handle 12. You can sit with plenty of room. In this state, the operator pulls the handle 12 toward the driver's seat 9 to move the upper column 16 and the jumping member 26 together with the support shafts 31 and 32 as the center. It can be rotated in the B direction.

  At this time, the inclined surface 30B of the cam plate 30 can smoothly guide the distal end surface of the lock pin 40 from the disengagement position shown in FIG. 7 to the engagement position shown in FIG. 6 can be engaged with the engagement hole 30A of the cam plate 30 as shown in FIG. As a result, the upper column 16 of the steering column 13 can be returned from the jumping position shown by the two-dot chain line in FIG. 3 to the driving position shown by the solid line, and the jumping member 26 is brought into the engagement position by the lock pin 40. Can be locked.

  Thus, according to the present embodiment, the lifting mechanism 25 extends between the lower column 14 and the upper column 16 in the upward and downward directions, and the intermediate portion in the length direction becomes the shaft support portion 14B of the lower column 14. A flip-up member 26 that is pivotally attached and whose upper side is fixed to the column frame 17 of the upper column 16 via a fastening bolt 34, and is provided so as to be displaceable on the lower column 14 side. A cam provided between a tapered lock pin 40 that engages with the cam plate 30 to position the upper column 16 in the operating position, and a protrusion 27C of the jumping member 26 and a spring receiving member 45 on the lower column 14 side. When the lock pin 40 is disengaged from the engagement hole 30 </ b> A of the plate 30, the upper column 16 is constituted by a jump spring 47 that jumps up together with the jump member 26.

  As a result, while the lock pin 40 is engaged with the flip-up member 26 rotatably attached to the shaft support portion 14B of the lower column 14, the upper column 16 is positioned at the driving position close to the driver's seat. In this state, the operator can easily perform the steering operation with the handle 12. In this case, the lock pin 40 can be urged toward the cam plate 30 side of the jumping member 26 by the lock spring 41, and the jumping operation of the jumping member 26 is restricted by the lock pin 40, so that the upper column 16 is moved. It can keep locked in the driving position.

  On the other hand, when the handle 12 gets in the way when the operator stands up and leaves the driver's seat 9, the spring force of the jump spring 47 is released by releasing the engagement of the lock pin 40 with the cam plate 30 of the jump member 26. Thus, the upper column 16 can be jumped up together with the jumping member 26, and the handle 12 can be moved to the jumping position away from the driver's seat 9. Further, by forming the tapered portion 40A at the engagement portion of the lock pin 40, the lock pin 40 can be smoothly engaged and released with respect to the engagement hole 30A of the jumping member 26, and the upper column 16 is operated. The operability when tilting to the position and the jumping position can be improved.

  Therefore, for the operator sitting in the driver's seat 9, the upper column 16 of the steering column 13 together with the handle 12 is separated from the driver's seat 9 by simply depressing the pedal 44 of the jumping mechanism 25 in an easy posture. It is possible to jump easily to the raised position, and the workability when getting on and off can be greatly improved. Further, the pin holding body 38 provided in the lower column 14 can hold the lock pin 40 at a position facing the cam plate 30 of the flip-up member 26 in the upward and downward directions so as to be displaceable. By means of a lock spring 41 provided between the lock pin 40 and the lock pin 40, the lock pin 40 can be constantly urged toward the cam plate 30 of the jumping member 26.

  Further, the pin operating member 42 provided in the pin holding body 38 is rotated in the pin holding body 38 in accordance with the depression operation of the pedal 44, so that the lock pin 40 is moved against the lock spring 41 in the pin holding body 38. The pin can be displaced upward and downward, and the pin operating member 42 can engage and release the lock pin 40 with respect to the cam plate 30 (engagement hole 30 </ b> A) of the jumping member 26.

  Further, according to the present embodiment, the jumping mechanism 25 that jumps the upper column 16 of the steering column 13 from the driving position to the jumping position is configured independently of the tilt angle adjustment mechanism 33 and the column length adjustment mechanism 37. Therefore, once the tilt angle of the steering column 13 is adjusted by the tilt angle adjusting mechanism 33 and the column length is adjusted by the column length adjusting mechanism 37, the respective adjustment positions can be maintained thereafter. .

  As a result, the operator getting on and off the driver's seat 9 can jump the steering column 13 together with the handle 12 in the direction away from the driver's seat 9 only by operating the pedal 44 of the jumping mechanism 25. Also, the tilt angle and the column length can be held at positions adjusted in advance. For this reason, when the user gets in the driver's seat 9 next time, it is not necessary to perform the adjustment operation of the tilt angle and the column length again, and the workability at the time of getting on and off can be greatly improved.

  Further, when an operator different from the previous one gets into the driver's seat 9, the tilt lever 35 is moved upward with the operator returning the steering column 13 from the jumping position to the driving position together with the handle 12. What is necessary is just to rotate. Thereby, the fastening state of the lifting member 26 with respect to the swing plate 27 by the support plate 23A, the cylindrical nut 24 and the fastening bolt 34 can be released, and the tilt angle adjusting mechanism 33 and the column length adjusting mechanism 37 are locked (held). State) can be released manually.

  Therefore, the operator can operate the tilt angle adjusting mechanism 33 and the column length adjusting mechanism 37 so as to manually move the handle 12, and adjust the position of the handle 12 according to his / her physique and preference. Can do. Then, at the time of getting on and off, it is possible to tilt the steering column 13 between the jumping position and the driving position in an easy posture for the operator only by operating the pedal 44 of the jumping mechanism 25. The jumping operation can be repeated while holding.

  The operator seated on the driver's seat 9 performs the operation of pulling the handle 12 toward the front side together with the steering column 13 so that the lock pin 40 of the jumping mechanism 25 is provided on the cam plate 30 of the jumping member 26. The upper column 16 of the steering column 13 can be returned to the operating position tilted forward with respect to the lower column 14, and in this case as well, the operator can steer with an easy posture. The column 13 can be returned to the operating position.

  Further, when an operator different from the previous one sits on the driver's seat 9 and operates the work device 7, the operator returns the steering column 13 from the jumping position to the driving position close to the driver's seat. By manually operating the tilt angle adjusting mechanism 33 and the column length adjusting mechanism 37, the position of the handle 12 can be appropriately adjusted according to its own physique and preference.

  That is, the tilt angle adjusting mechanism 33 can adjust the tilt angle of the steering column 13 (upper column 16) by tilting the upper column 16 forward and backward with respect to the lower column 14. Further, the column length adjusting mechanism 37 can adjust the column length of the steering column 13 by moving the upper column 16 upward and downward with respect to the lower column 14.

  In this case, the tilt angle adjusting mechanism 33 manually rotates the tilt lever 35, thereby rotating the cylindrical nut 24 relative to the fastening bolt 34 from the outside to release the fastening state of both. be able to. In this state, the upper column 16 can be relatively moved along the elongated hole portion 27B of the jumping member 26 (the swing plate 27). Accordingly, the upper column 16 can be tilted forward and backward with respect to the lower column 14 within the arc range of the long hole portion 27B, and the tilt angle of the steering column 13 can be finely adjusted.

  When the column length is adjusted together with the tilt angle, the upper column 16 can be moved upward and downward with respect to the lower column 14 by the column length adjusting mechanism 37. The column length can be fine-tuned manually. Thus, after adjusting the tilt angle and / or the column length, the fastening bolt 34 is rotated from the outside with respect to the cylindrical nut 24 by operating the tilt lever 35 in the reverse direction, and the upper column 16. And the tilt angle and the column length can be held at adjusted positions.

  In the above-described embodiment, the case where the jumping member 26 includes the swing plate 27, the plurality of bolts 28, the bending plate 29, and the cam plate 30 has been described as an example. However, the present invention is not limited to this. For example, as shown in FIGS. 9 and 10, the jumping member 26 may be formed in advance as a single member.

  In the above-described embodiment, the case where the upper column 16 of the steering column 13 is lifted up together with the jumping member 26 using the two jumping springs 47 has been described as an example. However, the present invention is not limited to this. For example, a spring member made of a gas spring or other elastic body may be used to jump up the upper column together with the jumping member.

  In the above embodiment, the case where the upper column 16 of the steering column 13 is jumped up by stepping on the pedal 44 has been described as an example. However, the present invention is not limited to this. For example, the upper column 16 may be lifted up by manually operating a manual lever or a push button other than the tilt lever 35.

  Moreover, in the said embodiment, the wheel loader 1 set as the structure which provides the canopy 10 above the driver's seat 9 was mentioned as an example, and was demonstrated. However, the present invention is not limited to this, and can also be applied to a construction machine such as a wheel loader, a wheel-type hydraulic excavator, or a crane having a cab that defines a cab inside.

  Furthermore, in the said embodiment, the wheel loader 1 was mentioned as an example as a construction machine provided with the steering apparatus 11, and was demonstrated. However, the present invention is not limited to this, and can be widely applied to construction machines such as a hydraulic excavator, a forklift, and a crane including a wheel-type traveling body.

1 Wheel loader (construction machine)
2 Car body 7 Working device 8 Floor board (floor surface)
9 Driver's seat 11 Steering device 12 Steering wheel 13 Steering column 14 Lower column 14B Shaft support 15 Lower shaft 16 Upper column 17 Column frame 17C, 17D Side plate 17C1, 17D1 U-shaped slit (length adjustment part)
17C2 I-shaped slit (length adjustment part)
18 mounting post 21 upper shaft 22 joint member 23 lever support 23A support plate 24 cylindrical nut (fastening member)
DESCRIPTION OF SYMBOLS 25 Jumping mechanism 26 Jumping member 27 Swing plate 27A, 29C Pivoting part 27B Long hole part 29 Bending plate 30 Cam plate 30A Engagement hole 30B Inclined surface 31, 32 Support shaft 33 Tilt angle adjustment mechanism 34 Fastening bolt ( Fastening member)
35 Tilt lever 37 Column length adjustment mechanism 38 Pin holder 38A, 38B Pin guide 38C Mounting cylinder 40 Lock pin 40A Taper 41 Lock spring (biasing member)
42 pin operating member 42A gripping portion 44 pedal 45 spring receiving member 47 spring (spring member)
48 Cushion material

Claims (6)

A steering column disposed on the front side of a driver's seat of a construction machine and steered by a steering wheel, and a jumping mechanism that jumps the steering column to a jumping position away from the driver's seat with respect to a driving position close to the driver's seat And
The lower side of the steering column is fixed to the floor side of the driver's seat, and the lower column extends upward and downward. The steering column is provided on the upper side of the lower column and is lifted by the jumping mechanism. Comprising an upper column and
The jump mechanism is
A jumping member that extends upward and downward between the lower column and the upper column, and a middle portion in the length direction is rotatably attached to the lower column, and an upper side is fixed to the upper column;
A lock pin that is displaceably provided on the lower column side and normally engages with the jumping member to position the upper column at the operating position;
A spring member provided between the jumping member and the lower column and configured to spring up the upper column together with the jumping member when the lock pin is disengaged from the jumping member. Steering device for construction machinery.   The steering device for a construction machine according to claim 1, wherein a biasing member that constantly biases the lock pin toward the jumping member is provided between the lower column and the lock pin.   The construction according to claim 1 or 2, wherein an engagement hole into which the lock pin is engaged is provided in the jumping member, and a portion of the lock pin that engages with the engagement hole is formed in a tapered shape. Mechanical steering device.   The raising mechanism includes a pedal provided on the lower column side and rotated by an operator seated on the driver's seat, and the lock pin is engaged with the raising member until the operator operates the pedal. The steering device for a construction machine according to claim 1, 2 or 3, wherein when the pedal is operated, the engagement with the jumping member is released.   The lower column is provided with a pin holding body that faces the jumping member in the upward and downward directions and holds the lock pin in a displaceable manner, and the lock pin is interposed between the pin holding body and the lock pin. The steering device for a construction machine according to claim 1, further comprising a biasing member that constantly biases toward the jumping member.   The pin holding body is provided with a pin operation member that displaces the lock pin upward and downward against the urging member, and the pin operation member is stepped on the tip side by an operator seated on the driver seat. The steering device for a construction machine according to claim 5, wherein the steering device is connected to a base end side of the pedal.

Images