JP6520591B2 - Cab guard equipped to the crane - Google Patents

Description

  The present invention relates to a cab guard provided to a cab of a mobile, fixed, etc. crane that can widen the view in the upper front while securing the safety of the operator who is on board.

Mobile cranes represented by crawler cranes and fixed cranes used for construction of high-rise buildings etc., for example, have a long boom ranging from several meters to several tens of meters, and use a hook device provided for this boom Work on high places (crane work) such as hanging various luggage.
An operator operating a mobile or fixed crane is performing crane work while looking at the suspended hook device. However, if the boom of this crane is long, the hook device being suspended may be at a high position, and the operator's line of sight may extend from the top front, i.e. from above the front window of the cab to the ceiling.

As a technique aiming at ensuring the field of vision of the upper front-the ceiling of the operator during crane work, there are some which were indicated by patent documents 1 and 2.
Patent Document 1 discloses a skylight opening at the roof, a head guard attached above the roof covering substantially the entire surface of the roof, and a headguard at the headguard located above the skylight. The operator's cab of a construction machine comprising an open part having a large opening, an open / close guard attached to the open part so as to be openable / closable, and a skylight attached to the open / close guard to open / close the skylight opening by opening / closing Is disclosed.

  According to Patent Document 2, the rear of the cab is projected rearward in the window structure of a cab of a construction machine having a front upper window which can be opened and closed by sliding along guide rails laid on the front and the ceiling. To extend the ceiling space and to extend the guide rails to the expanded ceiling space so that the frame of the front upper window does not block the operator's view when the front upper window is opened and stored under the ceiling A front window structure for a cab of a construction machine is disclosed.

JP 2008-127847 A Unexamined-Japanese-Patent No. 2003-312249

However, the following problems also exist in the techniques of Patent Documents 1 and 2 for the purpose of securing the upper front view of the operator.
Patent Document 1 provides an opening larger than the skylight body on the front side of a large head guard, attaches an opening and closing guard to the opening, and has a mechanism as a mechanism for jumping up the skylight body and the opening and closing guard. It is a cab (driver's cab) having an openable skylight body and an open / close guard which is located on the upper side of the skylight body and on the front side of the head guard and which can be opened and closed simultaneously with the skylight body.

  However, as shown in FIGS. 1 and 2 of the document, even if the skylight body and the opening / closing guard provided on the front side of the ceiling of the cab are flipped up to make the upper front of the operator visible, The raised skylight and the opening and closing guard do not provide a completely open state, and it seems difficult to secure a wide field of view of the operator in the upper front. It is also conceivable that the opening front frame of the head guard provided so as to extend in the left-right direction may block the line of sight of the operator.

That is, with reference to FIGS. 1 and 2, it is difficult to say that the technique of Patent Document 1 is sufficiently considered with respect to the operator's visibility (visibility) in the upper front.
In addition, the "bump-up mechanism" disclosed in Patent Document 1 has a large-scale and complicated structure, and if this mechanism is provided on the cab's ceiling (upper part), the weight of the cab may increase. The manufacturing cost may be increased.

On the other hand, Patent Document 2 is a technology that secures the upper front view of the operator by jumping up the skylight of the cab and sliding the front window to the ceiling for storage.
However, as shown in FIG. 4 of the same document, it is necessary to slide the front window to the rear in order to secure the upper front view of the operator, and the projection in the rear of the cab, ie, the total length of the cab is exceeded. A long guide rail must be provided in the front-rear direction. That is, it is necessary to secure a sufficient space where a long guide rail can be provided at the rear of the cab.

However, there may be a passage behind the cab for the operator to move to the cab or the like. In such a case, as disclosed in Patent Document 2, if a long guide rail protrusion is formed on the rear side wall of the cab, the operator may be hindered when moving the passage.
If a cab slide with such a slide rail with such a guide rail protruding backward or the above-mentioned large and complex "bounce mechanism" cab guard is provided on the ceiling of the cab, the cab becomes large and the weight of the cab body There is a risk that the height of the cab will be increased. For example, if the total height of the cab is increased, there is a possibility that problems such as failure to meet the "conveying height limitation" in a mobile crane when transporting by a truck or trailer may occur.

  By the way, the conventional techniques such as Patent Documents 1 and 2 mentioned above use a hydraulic shovel or the like as a representative example, and in this hydraulic shovel, usually, most of the work while looking at the front or the lower front is a crane work etc. There is no representative work at heights. Therefore, in the prior art such as Patent Documents 1 and 2, the visibility (visibility) of the upper front of the cab is not regarded as important. Even if the prior art such as Patent Documents 1 and 2 is applied to a crane that performs work at high places represented by a crane etc., visibility in the upper part of the cab is poor and work at high places safely and reliably Is difficult.

  Therefore, in view of the above problems, the present invention provides a cab guard provided to a crane capable of safely performing high-altitude work, for example, crane work, and allowing the operator to easily view the upper front and securing a wide field of view. Intended to be provided.

In order to achieve the above-mentioned object, the following technical measures are taken in the present invention.
A cab guard provided to such a crane according to the present invention is a cab guard provided on a cab of a crane provided with a boom extending in the front-rear direction and covering a ceiling of the cab, the cab guard being a first cab guard A guard member and a second guard member are provided, and the second guard member is disposed on the front side of the first guard member, and the front end of the first guard member is at the rear end of the second guard member. The first guard member is connected to and connected to a ceiling of the cab and is connected to the rear end of the first guard member. And the front end of the second guard member is movable in the front-rear direction with respect to the ceiling of the cab. Being done And wherein the Rukoto.

Preferably, the front end of the second guard member is movable along a guide rail provided so as to face the ceiling of the cab in the front-rear direction.
Preferably, a length in the front-rear direction of the second guard member is longer than a length in the front-rear direction of the first guard member.
Preferably, the first guard member is rotatably connected to a ceiling of the cab such that a front end can fall backward.

Preferably, when the front end of the first guard member falls back, the front end of the second guard member can be flipped up.
Preferably, the first guard member includes one member and another member, and the other member is disposed on the rear side of the one member, and the other member is disposed at the front end of the one member. The rear end may be connected, and may be rotatable about a horizontal axis about the connected point.

  According to the present invention, high-level work such as crane work can be performed safely, and the upper front of the operator can be easily seen and a wide field of view can be secured.

BRIEF DESCRIPTION OF THE DRAWINGS It is a side view which shows roughly the whole structure of the crawler crane in embodiment of this invention. It is a side view showing typically the composition of the cab body in an embodiment of the present invention, and a cab guard. It is a figure showing roughly the process of folding operation of a cab guard. It is a figure showing the modification of the cab guard of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In this embodiment, the cab is provided on the ceiling (upper part) of the cab 6 of the crane 1 and ensures safety above the cab 6 of the operator W when performing work at a high place (for example, crane work) The guard 18 will be described. The present invention is applicable to all construction machines including cranes, and is particularly suitable for cranes and building dismantling machines that require high-altitude work.

However, the crane 1 in which the cab guard 18 is provided on the ceiling of the cab 6 will be described by taking the crawler crane (mobile crane) as an example.
In the present specification, the upper revolving superstructure at a position where the traveling direction of the lower traveling vehicle 3 and the axial length direction of the boom 8 provided on the upper revolving superstructure 2 coincide, that is, the reference position (home position) of the crawler crane 1 The boom 8 arranged to extend from 2 and the cab 6 side mounted on the front side is the front side of the crawler crane 1 and the counterweight 13 side mounted on the upper revolving structure 2 is the rear side of the crawler crane 1 Do.

Further, one side in the width direction of the upper revolving superstructure 2 is taken as the right direction of the crawler crane 1 and the other side in the width direction of the upper revolving superstructure 2 is taken as the left direction of the crawler crane 1. This corresponds to the direction viewed from the operator W who got on the cab 6.
As shown in FIG. 1, the crawler crane 1 (hereinafter simply referred to as a crane) in the present embodiment supports the upper swing body 2 and the upper swing body 2 so as to freely turn from below and travels. Is equipped. In addition, a boom 8 is provided at the front of the upper swing body 2 in the center in the width direction to suspend a hook device 9 or the like via a suspension rope 10. A cab 6 (driver's cab) in which an operation unit for operating the boom 8 is disposed inside is mounted on the front side of the upper swing body 2 in the width direction one side (right side).

The lower traveling body 3 is provided with endless tracks (crawlers 4) formed by annularly forming metal bands, which can travel on the ground or road surface, at both ends in the left-right direction, and the upper swing body 2 A pivoting means 5 for pivotably supporting from below and pivoting about a longitudinal axis is provided at the top center.
In the upper revolving superstructure 2, a cab 6 in which an operation unit for operating the boom 8 described above is disposed is provided in front of one side (right side) in the left-right direction, a device for driving the crane 1 such as an engine An engine guard 7 stored inside is provided at the rear of the cab 6.

  In the upper revolving superstructure 2, a long boom 8 for suspending a hook device 9 or the like via a suspending rope 10 is provided at the front in the center in the left-right direction. A winch (drum) (not shown) for taking up the The upper revolving superstructure 2 is provided with a mast 12 on which an undulating rope 11 is wound and an undulation winch (not shown) for undulating the boom 8 by winding and unwinding the undulating rope 11. The counterweight 13 is disposed at the rear.

The cab 6 is a metal casing having a large space inside, a control unit for performing a crane operation is provided, and an operator can ride on the cab. Windows 15 and 16 for securing the view of the operator W are provided on the front and left and right sides of the cab 6, and a passenger door 14 (door) is provided on the side of one side.
Further, the ceiling front side of the cab 6 of the present embodiment is a transparent member such as glass, that is, a skylight 17 (ceiling window) in order to widen the field of view of the operator W.

Inside the cab 6, an operation unit (operation unit) for performing a crane operation by control of a control valve and a seat (both not shown) on which the operator W can sit are provided. The operator W seated on a seat inside the cab 6 operates the crane by operating the operation unit.
A cab guard 18 is provided on the ceiling of the cab 6 to ensure the safety above the cab 6 of the operator W when performing a crane operation.

As shown in FIG. 2, the cab guard 18 covers substantially the entire ceiling of the cab 6, and is a member formed in a lattice shape. By making the cab guard 18 into a grid shape and making the ceiling front side of the cab 6 a transparent member such as glass, the field of view of the operator W inside the cab 6 is secured.
Specifically, the cab guard 18 has a plurality of elongated plate members (steel members) extending in the front-rear direction such that the width of the plate members is directed vertically and a plurality of the plate members are arranged at predetermined intervals in the left-right direction. Between each other is connected by a connecting member or the like. That is, the cab guard 18 is shaped like a grating used for, for example, a groove cover of a side groove.

Furthermore, in the present embodiment, the cab guard 18 is a member that is configured to be split back and forth in two directions in the front and rear directions in order to improve the visibility of the operator W and make the field in the upper front wider. It is.
The cab guard 18 is disposed so as to be hung and covered on the front side to the middle side of the ceiling of the cab 6 (near the front window 16 of the cab 6 to a little behind the seat on which the operator W sits). In addition, the ceiling rear side of the cab 6 is a space for when the cab guard 18 is folded.

  In order to ensure the safety above the cab 6, the cab guard 18 has a width enough to cover the ceiling of the cab 6 and a predetermined thickness, and is a flat member having a substantially rectangular shape in plan view There is. In addition, the cab guard 18 has a left-right length (left-right width) substantially equal to the left-right width of the ceiling of the cab 6, and a front-rear length (front-back length) slightly shorter than the height of the ceiling It is assumed. That is, the cab guard 18 is formed in a size that can ensure the safety above the operator W seated on the seat in the cab 6.

  The cab guard 18 is supported at a fixed distance from the ceiling of the cab 6 by a support member 21 (supporting leg) provided upright on the ceiling of the cab 6. The support legs 21 are provided at substantially four corners of the ceiling of the cab 6 one by one. That is, two support legs 21 are provided upright on the ceiling of the cab 6 at two positions corresponding to the right side of the cab guard 18 and at two positions corresponding to the left side.

A guide rail 21 is provided so as to be stretched over the upper ends of two support legs 21 erected at a position corresponding to the right side of the cab guard 18. In addition, the guide rails 21 are disposed so as to be stretched over the upper ends of the two support legs 21 erected at a position corresponding to the left side of the cab guard 18.
That is, it can be said that the guide rails 21 (guide rails) are provided in a pair so as to face the ceiling of the cab 6 in the front-rear direction. The guide rail 22 is a long member for guiding the second guard member 20 (details will be described later) in the front-rear direction, and the length thereof is substantially the same as the front-rear length of the cab guard 18.

  The guide rails 22 provided as a pair at both ends in the left-right direction of the cab guard 18 include, for example, two wall members of a lower wall and a side wall, and the side wall and the lower wall are formed substantially at right angles It is also good. Specifically, the side wall of the cab guard 18 is disposed outside the cab guard 18 in the left-right direction, and the lower wall is disposed below the cab guard 18. That is, the guide rail 22 has an L-shaped cross section.

When the roller 23 provided at the front end of the second guard member 20 abuts on the lower wall of such a guide rail 22 and rolls in the longitudinal direction, the second guard member 20 moves in the longitudinal direction It is possible (the details will be described later).
Hereinafter, features of the cab guard 18 according to the present embodiment will be described in detail with reference to the drawings.

As shown in FIG. 2, the cab guard 18 has a first guard member 19 and a second guard member 20, and the second guard member 20 is disposed on the front side of the first guard member 19.
The first guard member 19 is hung, for example, from a center in the front-rear direction of the ceiling of the cab 6 to a position about 1/4 from the rear end of the cab 6 (about between the overhead of the operator W and the rear end of the door 14) Deployed to cover.

  The rear end of the first guard member 19 is connected to the support member 21 provided on the ceiling of the cab 6, and is pivoted about the horizontal axis about the ceiling of the cab 6 centering on the connected point It is considered free. Specifically, support pins 25 whose axis centers in the left and right direction are inserted into the upper ends of the two support legs 21 erected on the left and right of the rear side of the ceiling. The rear end of the first guard member 19 is rotatably connected (supported) around the axial center of a support pin 25 inserted in the upper ends of the two support legs 21.

As described above, the first guard member 19 is rotatably connected at the rear end about the axial center of the support pin 25 so that the front end can fall backward. That is, the first guard member 19 can be rotated 180 degrees in the front-rear direction.
On the other hand, the front end of the first guard member 19 is rotatably connected to the rear end of the second guard member 20.

The second guard member 20 is, for example, disposed so as to hang and cover the front end side of the ceiling of the cab 6 and the center (approximately from the vicinity of the front window 16 of the cab 6 to the overhead of the operator W).
The rear end of the second guard member 20 is connected to the front end of the first guard member 19 so as to be rotatable about an axis in the left-right direction. That is, the rear end of the second guard member 20 is connected to the front end of the first guard member 19 and is rotatable about a horizontal axis about the connected point.

  Specifically, the rear end of the second guard member 20 and the front end of the first guard member 19 are connected via a pivoting member (not shown) such as a hinge whose axial center is in the left-right direction. Do. When the first guard member 19 is rotated about the axial center of the support pin 25 in such a coupled state, the second guard member 20 connected to the first guard member 19 rotates about the horizontal axial direction. Will turn to

  At the front end of the second guard member 20, for example, a pair of rotatable rollers 23 is disposed in the left / right direction, and the rollers 23 are in contact with the lower wall of the guide rails 22 provided on the left and right of the second guard member 20. The roller 23 rolls in the guide rail 22 in the front-rear direction, whereby the rear end of the second guard member 20 rotates around the axial center direction of the rotation member, that is, the second guard member 20 moves in the front-rear direction. It will move.

  In addition, on the right side of the front end of the second guard member 20, a handle 24 having a size that can be grasped by the operator W is provided so as to protrude laterally. The operator W grasps the handle 24 when the cab guard 18 is folded (in the alternate long and short dashed line in FIG. 2) or flat (in the dashed line in FIG. 2) and the front end of the second guard member 20 is held. It is for moving backward or forward along the guide rail 22.

As described above, by supporting the second guard member 20 and the first guard member 19 so as to be rotatable about the horizontal axis, the front end of the second guard member 20 with respect to the ceiling of the cab 6 in the front-rear direction It is possible to move (slide). According to the cab guard 18 of the present embodiment, which is slidable, the range (field angle α) of the field of view of the operator W can be expanded.
The length (front-rear length) of the second guard member 20 in the front-rear direction is longer than the front-rear length of the first guard member 19. Thus, even when the cab guard 18 is in the folded state by lengthening the front-rear length of the second guard member 20 relative to the front-rear length of the first guard member 19, The front end to the middle part project forward, and the operator W's safety can be secured after the field of view of the operator W is made wide.

In the present embodiment, the field of view of the operator W can be made wider.
As shown in FIG. 2, when the front end of the first guard member 19 falls backward (the state where it is rotated 180 °), the second guard member 20 is capable of jumping up the front end.
Specifically, a stay 26 supporting the second guard member 20 is provided on the right side of the ceiling of the cab 6 when in the flipped up state (solid line in FIG. 2). The operator W uses the handle 24 to lift the second guard member 20 from the folded state upward and bring it up. After being flipped up, the operator W raises the rod-shaped stay 26 to the upper side of the cab 6 and hooks the tip of the stay 26 onto the second guard member 20 in the flipped up state, and this second guard member 20 Support
[Operation mode]
Hereinafter, an operation mode of the cab guard 18 according to the present embodiment described above will be described with reference to FIG.

  In describing the operation mode of the cab guard 18 of the present embodiment, the crane 1 is brought into a safe state in which the crane 1 is stopped. In the flat state, the front end portion of the first guard member 19 can be fixed so that the cab guard 18 does not vibrate during crane work or transport. In the present embodiment, the flip-up operation is performed from the state where the front end portion of the first guard member 19 is fixed.

  Further, as a method of fixing the cab guard 18, for example, a method of fixing the front end portion of the first guard member 19 using a lock member such as a clamp, a member such as a flange at the front end portion of the first guard member 19 A method for fixing the flange and the pin by engaging the flange and the pin, and the bottom end of the guide rail 22 is open at the front end so that the roller 23 provided on the first guard member 19 can be fitted therein. There is a method of providing a V-shaped groove and inserting and fixing the roller 23 in the groove.

As shown in FIG. 3A, the operator W releases the fixed state, and brings the first guard member 19 and the second guard member 20 constituting the cab guard 18 into an operable state.
As shown in FIG. 3 (b), the operator W grasps the handle 24 and moves the front end of the second guard member 20 rearward along the guide rail 22.
At this time, the first guard member 19 is in a state directed obliquely upward to the front, that is, rotated about the axial center of the support pin 25, and the front end is lifted obliquely upward in the front. On the other hand, the second guard member 20 rotates obliquely around the axial center of a pivoting member such as a hinge, so that the rear end is lifted obliquely upward and backward.

As shown in FIG. 3 (c), the first guard member 19 is rotated substantially vertically, that is, rotated about the axial center of the support pin 25 so that the front end is located almost directly above the rear end. Can be lifted. On the other hand, the second guard member 20 is further inclined obliquely upward to the rear, that is, rotated about the axial center of the pivoting member, and the rear end is lifted obliquely upward and backward.
As shown in FIG. 3D, the operator W moves the front end of the second guard member 20 further rearward along the guide rail 22.

At this time, the first guard member 19 rotates about the axial center of the support pin 25 in a state of turning obliquely upward to the rear, and the front end moves rearward from the rear end. That is, the first guard member 19 falls back. On the other hand, the second guard member 20 is further directed obliquely rearward and upward, that is, it rotates about the axial center of the rotation member, and the rear end moves rearward from the support leg 21 on the rear side.
As shown in FIG. 3E, the operator W separates the front end of the second guard member 20 from the guide rail 22 to place the second guard member 20 and the first guard member 19 in a superposed state.

At this time, the first guard member 19 is rotated approximately 180 ° to move in a substantially horizontal state facing in the front-rear direction, that is, the rear end moves to a position behind the front end on the same axial line in the front-rear direction. The second guard member 20 moves to a substantially horizontal state in the front-rear direction, that is, the rear end moves to a position just above the front end of the first guard member 19.
As shown in FIG. 3 (f), the operator W grasps the handle 24 and flips up the cab guard 18 to open the upper part of the cab 6. At this time, the first guard member 19 is in a substantially horizontal state facing in the front-rear direction (similar to FIG. 3E). On the other hand, the second guard member 20 rotates about the axial center of the rotation member, and the front end is flipped up.

Thereafter, the operator W lifts the laid stay 26 upward in order to maintain the raised state of the cab guard 18 (second guard member 20), and the tip thereof is placed on the right side wall of the second guard member 20. Engage.
FIG. 3 (e) shows a state in which the first guard member 19 and the second guard member 20 are superimposed, but this state is a view showing the progress of the flip-up operation, and the state of superposition is not necessarily required. It is not something that has to go through. For example, the first guard member 19 may be leveled and the second guard member 20 may be flipped up without being in the polymerization state.

  In addition, the first guard member 19 and the second guard member 20 connected in a hinge shape are not completely closed, that is, in a state where they are not bent to one side by a predetermined angle or more (non-polymerized state), It is also possible to perform a flip-up operation. By putting the first guard member 19 and the second guard member 20 in a non-polymerized state, the second guard member 20 can be prevented from hanging down, and the stay 26 need not be provided.

  Moreover, in FIG. 3F, it is an example of a flipping up state, and as long as the second guard member is reliably flipped up, it is not limited to the state shown in FIG. 3F. That is, although the first guard member 19 is rotated approximately 180 ° to the rear side to be in the substantially horizontal state, the first guard member 19 may not necessarily be in the substantially horizontal state. For example, the front end portion of the first guard member 19 may be raised upward. In addition, the raising angle of the 2nd guard member with respect to the ceiling of the cab 6 can be arbitrarily selected by the condition of a crane operation | work.

Now, in order to make the cab guard 18 flat from the flipped up state, it is preferable to carry out by the reverse procedure of the folding operation of the cab guard 18 described above (operation from FIG. 3 (f) to FIG. 3 (a)).
Specifically, the operator W grasps the handle 24, moves the second guard member 20 forward, and brings the roller 23 at the front end into contact with the guide rail 22. Furthermore, the second guard member 20 is moved forward, and the first guard member 19 is rotated about the axial center of the support pin 25 and moved so as to fall forward. Then, the second guard member 20 is moved forward until the first guard member 19 and the second guard member 20 face a substantially horizontal direction, that is, a flat state.

According to the cab guard 18 of the present invention, it is possible to secure a wider field of view than the prior art while securing the safety of the operator W during crane work.
Since the cab guard 18 of the present invention only slides the roller 23 disposed at the front end of the second guard member 20 on the guide rail 22, it can be lifted with a light force. In addition, the cab guard 18 according to the present invention has a simple folding mechanism, so that problems such as an increase in size of the cab 6 and an increase in the weight of the main body can be avoided. be able to.

Furthermore, according to the present invention, the ceiling (skylight 17) of the cab 6, which is a transparent member such as glass, can be easily cleaned.
[Modification]
Next, a modification of the cab guard 18 of the present invention will be described based on the drawings.
As shown to Fig.4 (a), in this modification, the 1st guard member 27 is attached to the ceiling of the cab 6 via the 3rd guard member 28. As shown in FIG.

The third guard member 28 is a non-operating member fixed to the support member 21 at the ceiling at the rear of the cab 6, and is a member constituting the ceiling of the cab 6. That is, in the present modification, the third guard member 28 is regarded as the ceiling of the cab 6.
A first guard member 27 is disposed on the front side of the third guard member that constitutes the ceiling of the cab 6. The front end of the third guard member is connected to the rear end of the first guard member 27, and the first guard member 27 is turned around the horizontal axis with respect to the ceiling of the cab 6 centering on the connected point. It is considered to be movable.

As shown in FIG. 4 (b), when the second guard member 20 is flipped up, the first guard member 27 is placed on the upper portion of the third guard member 28, that is, in the overlapping state. It is assumed that the That is, this modification has a shape in which the first guard member 27, the second guard member 20, and the third guard member 28 are broken into three.
In the case of this modification, the first guard member 27 and the third guard member 28 have substantially the same length in the front-rear direction, and the length in the front-rear direction of the first guard member 19 described in the above embodiment. Is a shorter member. That is, the first guard member 27 and the third guard member 28 have substantially the same shape.

  The first guard member 27 and the third guard member 28 of this modification may be, for example, about half the length of the first guard member 19 described in the above embodiment. That is, in this modification, the length in the front-rear direction of the first guard member 27 and the third guard member 28 is the same as the length in the front-rear direction of the first guard member 19 described in the above embodiment. Alternatively, it may be slightly longer.

The widths of the first guard member 27 and the third guard member 28 in the present modification are both substantially the same as the width of the first guard member 19 described in the above embodiment.
According to this modification, since the second guard member 20 is flipped up largely, it is possible to secure a wider visual field while securing the safety of the operator W during the crane operation.

It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect.
For example, in the present embodiment, the handle 24 is disposed on the front right side of the second guard member 20 and the cab guard 18 is folded from the right side of the cab 6 by way of example. The two guard members 20 may be disposed on the left side, and the cab guard 18 may be folded from the left side of the cab 6. For example, it is preferable that the folding operation of the cab guard 18 can be safely performed from the door 14 side of the cab 6. The handles 24 may be disposed on both sides of the second guard member 20.

Further, the cab guard 18 is not particularly limited as long as it can ensure the safety of the operator W during the crane operation (shape, material, etc.). The guide rail 21 is not particularly limited as long as it can easily guide the second guard member 20.
In particular, in each embodiment disclosed this time, matters not explicitly disclosed, for example, operating conditions and conditions, various parameters, dimensions of components, weights, volumes, etc. Without deviating from this, those skilled in the art will employ values that can easily be envisioned.

1 Mobile crane (crane)
Reference Signs List 2 upper swing body 3 lower travel body 4 crawler 5 turn means 6 cab 7 engine guard 8 boom 9 hook device 10 suspension rope 11 relief rope 12 mast 13 counter weight 14 doorway
DESCRIPTION OF SYMBOLS 15 Window 16 Front window 17 Skylight 18 Cab guard 19 1st guard member 20 2nd guard member 21 Support member (support leg)
22 Guide rails (guide rails)
23 Roller 24 Handle 25 Support Pin 26 Stay 27 First Guard Member (Modified Example)
28 Third guard member W operator

Claims (5)

A cab guard provided on a cab of a crane provided with a boom extending in a longitudinal direction and covering a ceiling of the cab,
The cab guard has a first guard member and a second guard member, and the second guard member is disposed on the front side of the first guard member.
The front end of the first guard member is connected to the rear end of the second guard member, and is rotatable about a horizontal axis about the connected point,
The rear end of the first guard member is connected to the ceiling of the cab, and is rotatable about a horizontal axis about the ceiling of the cab around the connected point,
A front end of the second guard member is movable in the front-rear direction with respect to a ceiling of the cab. A cab guard provided on a crane according to claim 1.   The crane according to claim 1, wherein the front end of the second guard member is movable along a guide rail provided to face in the front-rear direction on a ceiling of the cab. Cab guard.   The cab according to claim 1 or 2, wherein a length of the second guard member in the front-rear direction is longer than a length of the first guard member in the front-rear direction. guard.   The crane according to any one of claims 1 to 3, wherein the first guard member is rotatably connected to a ceiling of the cab such that a front end can fall backward. Cab guard equipped in the house.   The crane according to any one of claims 1 to 4, wherein when the front end of the first guard member falls backward, the front end of the second guard member can bounce up. Equipped cab guard.