JP5551466B2 - Outrigger ground contact detector for self-propelled crane - Google Patents

Description

  The present invention relates to a self-propelled crane including an outrigger that is housed in a folded state, and more particularly, to an outrigger grounding detection device that detects a grounding state of an overhanging outrigger.

  Self-propelled cranes such as crawler cranes are provided with outriggers on the front, rear, left and right sides of the traveling vehicle body in order to ensure a stable state during operation. If the outriggers are not completely grounded when starting or during crane operation, there is a risk of falling. For this reason, in Patent Documents 1 and 2, the ground reaction force applied to the outrigger is detected by the load sensor, and a predetermined calculation is performed on the detection result to monitor whether all the outriggers are completely grounded. There has been proposed a crane overturn prevention device. The detection mechanism that detects the ground reaction force applied to the outrigger with a sensor such as a load cell has a high sensor cost and requires a signal processing circuit that performs calculation on the detection signal to detect whether the outrigger is completely grounded. So the manufacturing cost is high.

  Therefore, the applicant of the present application has proposed a self-propelled crane including a monitoring device that can reliably and reliably monitor the state of the outrigger in Patent Document 3. In the monitoring device disclosed herein, a grounding member that rotates around the horizontal axis and switches the posture with respect to the outrigger body during grounding is attached to the grounding portion of the outrigger, and the grounding member is in the grounding posture or the non-grounding posture in each of the outriggers. Is detected by a detector.

JP 2004-307188 A Japanese Patent Laid-Open No. 2003-171087 JP 2007-8642 A

  Here, the monitoring device proposed in Patent Document 3 is intended for a case where the arm on the distal end side of the outrigger to which the grounding member is attached is grounded with respect to the grounding surface. As an outrigger mounted on a self-propelled crane, there is an outrigger in which the arm on the tip end side (grounding side) is grounded in a substantially vertical posture when protruding from a state where it is stored in a traveling vehicle body in a folded state. In this case, the grounding member attached to the tip of the arm does not rotate around the horizontal axis at the time of grounding, or the amount of rotation is very small, and the change in the attitude of the grounding member cannot be detected.

  In view of these points, the object of the present invention is to reliably detect the grounding state regardless of the posture of the grounded arm when the outrigger stored in the folded state is extended. Another object of the present invention is to propose an inexpensive outrigger grounding detection device that can be used.

  In order to solve the above-described problems, the outrigger ground contact detection device of the present invention is characterized by having the following configuration. In addition, although the code | symbol shown in parenthesis has shown the corresponding site | part in embodiment mentioned later, these codes | symbols were attached | subjected in order to make an understanding of this invention easy, and this invention is made into embodiment. It is not intended to be limiting.

That is, according to the present invention, when the outrigger cylinder (15) attached to each of the plurality of outriggers (10) mounted on the traveling vehicle body (2) is extended, the outrigger (10 Is an outrigger ground detection device (30) for detecting the grounding state of each outrigger (10) in the self-propelled crane (1) in which the grounding state of the outrigger (10) is formed. ,
The cylinder-side connecting portion (15a) of the outrigger cylinder (15) can be moved by a predetermined amount when the reaction force applied to the outrigger cylinder (15) is greater than or equal to a predetermined value. ) Is connected to the fixed side connecting portions (19, 31) provided on the body frame (5) side,
The detector (33) is arranged so as to be turned on and off by the relative movement of the cylinder side connecting portion (15a) with respect to the fixed side connecting portion (19, 31).

  In the present invention, focusing on the outrigger cylinder (15) for projecting the outrigger (10), an outrigger cylinder (generated by a reaction force (ground reaction force) acting on the outrigger cylinder (15) from the outrigger (10) at the time of ground contact is provided. 15) and the vehicle body frame (5) supporting the same are used to switch the detector (33) so that the grounding state can be detected easily and reliably. That is, when the outrigger (10) is grounded, a reaction force acts on the outrigger cylinder (15) along with it, and the reaction force when an appropriate grounding state is formed becomes a predetermined value or more. Accordingly, if the detector (33) is set to be switched when the cylinder side connecting portion (15a) moves more than a predetermined amount with respect to the fixed side connecting portion (19, 31), the outrigger (10) The grounding state can be reliably detected. Further, the grounding state can be accurately detected regardless of the posture of the outrigger (10).

In addition to the above configuration, the outrigger ground contact detection device (30) of the self-propelled crane of the present invention includes:
The fixed side connecting portion includes a connecting shaft (19) attached to the vehicle body frame (5) and a dog (31) attached to the connecting shaft (19) so as to be rotatable .
The cylinder side connecting portion is connected to the dog (31) in a state in which the cylinder side connecting portion is slidable by a certain amount in the direction of the central axis (15A) of the outrigger cylinder (15), and the connecting shaft ( 19) a cylinder rear end portion (15a) rotatably connected to the compression coil spring (32) urging the outrigger cylinder (15) toward the distal end side of the dog (31). ) and a,
The detector is a limit switch (33) attached to the cylinder rear end (15a) or the dog (31) ,
When the cylinder rear end (15a) slides toward the rear end of the outrigger cylinder (15) with respect to the dog (31), the limit is caused by the dog (31) or the cylinder rear end (15a) . The detection piece (33a) of the switch (33) is pushed in, and a signal indicating that the outrigger (10) is in a grounded state is output from the limit switch (33) .

Moreover, the said outrigger (10) accommodated in a folding state can be set as the following structure. That is, the outrigger (10)
A horizontal swivel mounting portion (11) capable of swiveling around a vertical axis (16) attached to the vehicle body frame (5);
A first turning fixing portion (17) for fixing the horizontal turning type attaching portion (11) to one of a plurality of horizontal turning angle positions;
A first arm (12) capable of turning up and down around a first horizontal axis (18) attached to the horizontal turning attachment (11);
A second arm (13) pivotable up and down around a second horizontal axis (20) attached to the tip (12b) of the first arm (12);
A second turning fixing part (22A to 22D, 23) for fixing the second arm (13) to one of a plurality of turning angle positions in the vertical direction;
A ground plate (14) attached to the tip of the second arm (13),
The outrigger cylinder (15) is spanned between the connecting shaft (19) attached to the horizontal swivel attachment part (11) and the tip part (12b) of the first arm (12),
When the outrigger cylinder (15) extends, the first arm (12) extends from the folded state (10A) extending in the vertical direction to an overhanging state (10B, 10D) pivoted about the first horizontal axis (18). It is comprised so that it may become.

Next, the self-propelled crane (1) of the present invention is
A crane (4),
A traveling vehicle body (2) on which the crane (4) is mounted;
Four outriggers (10) housed in a folded state at left and right front and rear portions of the traveling vehicle body (2);
An outrigger grounding detecting device for detecting a grounding state of the outrigger (10),
When the outrigger cylinder (15) attached to each of the outriggers (10) is extended, the outrigger (10) in a folded state is extended to form a grounded state of the outrigger (10). And
The outrigger ground detection device is an outrigger ground detection device (30) configured as described above.

  In the outrigger ground contact detection device according to the present invention, the relative movement between the outrigger cylinder and the vehicle body frame that supports the outrigger cylinder caused by the reaction force (ground reaction force) that acts on the outrigger cylinder from the outrigger during grounding is detected by a mechanical switch. I try to detect it. Therefore, it is possible to detect the ground state easily and reliably without using a load cell or the like. In addition, the grounding state can be accurately detected regardless of the posture of the outrigger. Furthermore, when a detector is attached to the tip of the outrigger, a large impact force may act on the tip when the outrigger is extended, and the detector may be damaged. Evil can also be avoided.

(A) is a top view which shows the small crawler crane to which this invention is applied, (b) is the side view, (c) is a rear view. (A) And (b) is explanatory drawing which shows two examples of the outrigger projecting grounding state of the small crawler crane of FIG. (A) is a side view which shows the outrigger of the small crawler crane of FIG. 1, (b) is an end view at the time of seeing from the orthogonal direction. (A) is a side view showing a detection unit attached to the rear end portion of the outrigger cylinder of FIG. 3, (b) is an end view when viewed from the orthogonal direction, (c) is that portion It is sectional drawing, (d) is a fragmentary sectional view which shows the part cut | disconnected by the dd line | wire of (c).

  Hereinafter, an embodiment of a small crawler crane provided with an outrigger ground contact detection device to which the present invention is applied will be described with reference to the drawings.

(overall structure)
Fig.1 (a) is a top view which shows the small crawler crane which concerns on this Embodiment, (b) is the side view, (c) is a rear view. 2A and 2B are explanatory views showing two examples of the outrigger projecting grounding state. The small crawler crane 1 includes a crawler traveling vehicle body 2 and a crane 4 having a multistage boom 3. The multistage boom 3 is supported by a turntable 6 mounted on a vehicle body frame 5 of the traveling vehicle body 2.

  Outriggers 10 (1) to 10 (4) are respectively attached to both side portions of the front end portion and both side portions of the rear end portion of the vehicle body frame 5. As shown in FIG. 1, these four outriggers 10 (1) to 10 (4) are projected from the stowed state 10A folded almost vertically, and from the minimum projected state 10B shown in FIG. 2 (a). It is possible to make the projecting state within the range up to the maximum projecting state 10D shown in FIG. Since each outrigger 10 (1) -10 (4) has the same structure, in the following description, these may be collectively described as the outrigger 10.

  The outrigger 10 includes a horizontal swivel mounting portion 11 mounted on the vehicle body frame 5, a first arm 12 having a rear end portion 12 a connected to the horizontal swivel mounting portion 11, and a front end portion 12 b of the first arm 12. The second arm 13 is connected to the rear end portion 13a, and the ground plate 14 is attached to the front end portion 13b of the second arm 13. In addition, an outrigger cylinder 15 for vertically turning (raising and lowering) the first arm 11 is provided, and the outrigger cylinder 15 is extended between the horizontal turning type attachment portion 11 and the tip end portion 12 b of the first arm 12. Has been passed.

  FIG. 3A is a side view showing the outrigger 10 of the small crawler crane 1, and FIG. 3B is an end view when seen from the orthogonal direction. The structure of the outrigger 10 will be described with reference to FIG. First, the horizontal swivel mounting portion 11 is mounted on the vehicle body frame 5 so as to be able to turn around a vertical shaft 16 attached to the vehicle body frame 5. By changing the insertion position of the first positioning pin 17, the horizontal swivel mounting portion 11, for example, as shown in FIG. Positioning to 11C and 11D is possible.

  A first horizontal shaft 18 and a first horizontal connecting shaft 19 are attached to the horizontal swivel attachment portion 11. The rear end 12a of the first arm 12 is connected to the first horizontal shaft 18 in a rotatable state. A rear end portion 15a of the outrigger cylinder 15 is connected to the first horizontal connecting shaft 19 in a rotatable state. A second horizontal shaft 20 and a second horizontal connecting shaft 21 are attached to the distal end portion 12 b of the first arm 12. A rear end portion 13a of the second arm 13 is rotatably connected to the second horizontal shaft 20, and a distal end portion 15c of the telescopic rod 15b of the outrigger cylinder 15 is rotated to the second horizontal connection shaft 21. Connected in a possible state.

  Here, the front end portion 12 b of the first arm 12 is formed with four sets of pin holes 22 </ b> A to 22 </ b> D for defining the vertical turning position of the second arm 13, and the rear end portion of the second arm 13. One pin hole (not shown) is formed in 13a. By changing the insertion position of the second positioning pin 23 that can be inserted into these holes, as shown in FIG. 1, the second arm 13 is folded from the storage position 13 </ b> A in a state where it is folded to the first arm 12 side. 2B, a turning position 13B capable of forming the minimum overhanging state, a turning position 13D capable of forming the maximum overhanging state shown in FIG. 2B, and a turning position 12C capable of forming an intermediate overhanging state thereof. It can be fixed to.

  The second arm 13 is a two-stage telescopic arm, and can be pulled out from the fixed arm 13 (1) connected to the first arm 12 and the tip of the fixed arm 13 (1). A pull-out arm 13 (2) is provided, and a ground plate 16 is connected to the tip of the pull-out arm 13 (2) via a connecting shaft 24. The pull-out amount of the pull-out arm 13 (2) can be changed in multiple stages by changing the insertion position of the fixed pin 26 into the plurality of pin holes 25 formed along the axial direction.

(Outrigger ground detection device)
Next, the small crawler crane 1 is equipped with an outrigger grounding detection device for detecting the grounding state of each outrigger 10 in a state in which each outrigger cylinder 15 is extended to project each outrigger 10. As shown in FIG. 3A, the outrigger grounding detection device 30 is incorporated in each outrigger 10, and the grounding state is monitored by a control unit (not shown) based on the detection signal from here. .

  FIG. 4A is a side view showing the outrigger grounding detection device incorporated in each outrigger 10, FIG. 4B is an end view when viewed from the orthogonal direction, and FIG. FIG. 4D is a partial cross-sectional view showing a portion cut along a line dd in FIG. 4C. The configuration of the detection unit will be described with reference to FIGS. 3 and 4.

  The outrigger contact detection device 30 includes a first horizontal connecting shaft 19 to which a rear end portion 15a of the outrigger cylinder 15 is connected, a dog 31 rotatably attached to the horizontal connecting shaft 19, and a biasing force of the dog 31. A pair of compression coil springs 32 and a limit switch 33 attached to the rear end 15a of the outrigger cylinder 15 are provided. The first horizontal connecting shaft 19 and the dog 31 are fixed side connecting portions attached to the horizontal turning type attaching portion 11 mounted on the body frame 5 side, and the rear end portion 15a of the outrigger cylinder 15 is the dog 31. On the other hand, the cylinder-side connecting portion is connected to the dog 31 in a state in which it can slide by a certain amount in the direction of the central axis 15A of the outrigger cylinder 15.

  In this example, the limit switch 33 (mechanical switch) is used as a detector. However, other types of detectors such as an optical type may be used.

  The rear end portion 15a of the outrigger cylinder 15 includes a pair of left and right side plates 35, 36 attached to the rear end surface 34 of the outrigger cylinder 15, and an end plate 37 attached to these ends. Is stored. The dog 31 is relatively slidable in the direction of the central axis 15 </ b> A along the inner side surfaces of the side plates 35 and 36. A pair of recesses are formed in the opposing end surface 31a of the dog 31 facing the rear end surface 34, and a compression coil spring 32 extending in the direction of the central axis 15A is mounted in a state compressed by the rear end surface 34. Yes. The spring force of the compression coil spring 32 maintains a state in which a certain gap is formed between the rear end surface 34 of the outrigger cylinder 15 and the opposing end surface 31a of the dog 31.

  A limit switch 33 is attached to the outer surface of one side plate 36, and the tip of the detection piece 33 a of the limit switch 33 penetrates the end plate 36 and protrudes inward. On the side surface of the dog 31 facing the detection piece 33a, there are a side surface portion 31b at a position retracted so as not to interfere with the detection piece 33a, and an inclined surface portion 31c continuously inclined toward the detection piece 33a. Is formed. When the outrigger cylinder 15 slides backward, the detection piece 33a of the limit switch 33 also moves in the same direction, so that the detection piece 33a is pushed in by the inclined side surface portion 31c of the dog 31 on the fixed side, and the limit switch 33 is turned on from off. Switch to

  Contrary to this example, the limit switch 33 can be arranged on the dog 31 (fixed side connecting portion) side, and the detection piece 33a of the limit switch 33 can be pushed into the rear end portion 15a (cylinder side connecting portion) side. It is also possible to form a simple engaging surface.

  The operation of the outrigger ground detection device 30 having this configuration will be described. When the outrigger 10 is housed, the outrigger cylinder 15 is in a no-load state, and the outrigger cylinder 15 is pushed to the end plate 37 as a whole by the compression coil spring 32. Therefore, as shown in FIG. 4, the detection piece 33 a of the limit switch 33 is not engaged with the side surface of the dog 31 and is held in the off state.

  When the outrigger cylinder 15 is extended to project the outrigger 10 and come into contact with the ground, a reaction force acts on the outrigger 10. The reaction force acts in the direction of pushing the outrigger cylinder 15 around the first horizontal shaft 18 of the rear end portion 12a of the first arm 12, as indicated by an arrow in FIG. When the load (pushing force) acting on the outrigger cylinder 15 exceeds the spring force of the compression coil spring 32, the compression coil spring 32 is crushed and the outrigger cylinder 15 as a whole against the dog 31 attached to the first horizontal connecting shaft 19 Slide backwards. As a result, the inclined side surface portion 31c of the dog 31 engages with the detection piece 33a of the limit switch 33, pushes in the detection piece 33a, and the limit switch 33 is switched from OFF to ON.

  The detection signal of the limit switch 33 is sent to a control unit (not shown). The control unit monitors the state of the detection signal of the limit switch 33, and when it is switched on, it is determined that the outrigger 10 has been properly grounded.

  Even in a state where the crane work is performed with the outrigger 10 extended, the control unit monitors the detection signal of the limit switch 33 of each outrigger 10. When the detection signal of the limit switch 33 is switched from on to off during the crane work, it is determined that the outrigger 10 to which the limit switch 33 is attached has been lifted for some reason, for example, an alarm signal or the like. The crane operation is prohibited in the direction of increasing the load factor.

  Therefore, the control unit can monitor whether all the four outriggers 10 are normally grounded based on the output from the limit switch 33 before the crane work. When any one of the four outriggers 10 determines that the ground plate 14 is in a non-grounded state, a warning signal to that effect can be output. In this case, the operator can be notified by a lamp display or a warning sound, and the start of crane work can be prevented. Such monitoring work is also performed during crane work, and the control unit outputs a warning signal that the ground plate 14 is in a non-grounded state in any one of the four outriggers 10, The operator can be alerted with a lamp display and a warning sound, and the start of crane work can be stopped urgently.

  It should be noted that a timer is incorporated in the control unit, and the ground plate 14 is only output when the outrigger ground detection device 30 outputs that the ground plate 14 is in a non-grounding posture for a predetermined time or longer, for example, several seconds or longer, during crane work. May be determined to be in an ungrounded state. Even if the grounding plate 14 is lifted for a moment due to an impact or the like during the crane work, it is not determined that there is an abnormality if it is lifted for such a short time, so that the crane work can be prevented from being interrupted unnecessarily.

DESCRIPTION OF SYMBOLS 1 Small crawler crane 2 Traveling vehicle body 3 Multistage boom 4 Crane 5 Body frame 6 Swivel base 10, 10 (1) -10 (4) Outrigger 10A Storage state 10B Minimum overhanging state 10D Maximum overhanging state 11 Horizontal swivel mounting part 12 1st Arm 12a Rear end 12b Front end 13 Second arm 13a Rear end 13b Front end 14 Ground plate 15 Outrigger cylinder 15a Rear end 15b Telescopic rod 15c Front end 16 Vertical shaft 17 First positioning pin 18 First horizontal shaft 19 First 1 horizontal connecting shaft 20 second horizontal shaft 21 second horizontal connecting shafts 22A to 22D pin hole 23 second positioning pin 24 connecting shaft 25 pin hole 26 fixing pin 30 outrigger grounding detecting device 31 dog 31a opposed end surface 31b side surface portion 31c inclined side surface Portion 32 Compression coil spring 33 Limit switch 33a Detection piece 3 The rear end surface 35, 36 the side plates 37 the end plate

Claims (3)

When the outrigger cylinder (15) attached to each of the plurality of outriggers (10) mounted on the traveling vehicle body (2) is extended, the outrigger (10) stored in a folded state is extended. An outrigger ground detection device (30) for detecting the grounding state of each outrigger (10) in the self-propelled crane (1) in which the grounding state of the outrigger (10) is formed,
When the reaction force acting on the outrigger cylinder (15) is greater than or equal to a predetermined value, the cylinder-side connecting portion of the outrigger cylinder (15) can be moved by a predetermined amount so that the vehicle body of the traveling vehicle body (2) can move. It connects with the fixed side connection part (19, 31) provided in the frame (5) side,
The detector (33) is arranged so as to be turned on and off by the relative movement of the cylinder side connecting portion with respect to the fixed side connecting portion (19, 31) ,
The fixed side connecting portion includes a connecting shaft (19) attached to the vehicle body frame (5) and a dog (31) attached to the connecting shaft (19) so as to be rotatable.
The cylinder side connecting portion is connected to the dog (31) in a state in which the cylinder side connecting portion is slidable by a certain amount in the direction of the central axis (15A) of the outrigger cylinder (15), and the connecting shaft ( 19) a cylinder rear end portion (15a) rotatably connected to the compression coil spring (32) urging the outrigger cylinder (15) toward the distal end side of the dog (31). ) And
The detector is a limit switch (33) attached to the cylinder rear end (15a) or the dog (31),
When the cylinder rear end (15a) slides toward the rear end of the outrigger cylinder (15) with respect to the dog (31), the limit is caused by the dog (31) or the cylinder rear end (15a). Outrigger grounding of a self-propelled crane , wherein the detection piece (33a) of the switch (33) is pushed in and a signal indicating that the outrigger (10) is in a grounding state is output from the limit switch (33). Detection device (30). In claim 1,
The outrigger (10)
A horizontal swivel mounting portion (11) capable of swiveling around a vertical axis (16) attached to the vehicle body frame (5);
A first turning fixing portion (17) for fixing the horizontal turning type attaching portion (11) to one of a plurality of horizontal turning angle positions;
A first arm (12) capable of turning up and down around a first horizontal axis (18) attached to the horizontal turning attachment (11);
A second arm (13) pivotable up and down around a second horizontal axis (20) attached to the tip (12b) of the first arm (12);
A second turning fixing part (22A to 22D, 23) for fixing the second arm (13) to one of a plurality of turning angle positions in the vertical direction;
A ground plate (14) attached to the tip of the second arm (13),
The outrigger cylinder (15) is spanned between the connecting shaft (19) attached to the horizontal swivel attachment part (11) and the tip part (12b) of the first arm (12),
When the outrigger cylinder (15) extends, the first arm (12) extends from the folded state (10A) extending in the vertical direction to an overhanging state (10B, 10D) pivoted about the first horizontal axis (18). outrigger ground detector of self-propelled crane characterized by comprising (30). A crane (4),
A traveling vehicle body (2) on which the crane (4) is mounted;
Four outriggers (10) housed in a folded state at left and right front and rear portions of the traveling vehicle body (2);
An outrigger grounding detecting device for detecting a grounding state of the outrigger (10),
When the outrigger cylinder (15) attached to each of the outriggers (10) is extended, the outrigger (10) in a folded state is extended to form a grounded state of the outrigger (10). In the crane (1)
The self-propelled crane (1), wherein the outrigger ground contact detection device is the outrigger ground contact detection device (30) according to claim 1 or 2.

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