JP2545740Y2 - Mobile crane counterweight attachment / detachment device - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a mobile crane cowl.
The present invention relates to a device for attaching and detaching a weight .

[0002]

2. Description of the Related Art As shown in FIGS. 7 to 9, a mobile crane is provided with a swivel 4 having a telescoping boom 3 which can be raised and lowered on a frame 2 of a vehicle 1 and is provided at the rear of the swivel 4. A counterweight 5 is detachably attached to the end via an attachment / detachment device A. When the mobile crane travels, the counterweight 5 is detached from the rear end of the swivel base. The removed counterweight 5 is placed on the frame 2 between the operator's cab of the vehicle 1 and the swivel base 4 so as to balance the weight of the mobile crane during traveling, or Is transported by another vehicle to reduce the weight during traveling. Counter weight 5
The weight mounting table 5a is composed of a weight mounting table 5a and weights 5b stacked and mounted on the weight mounting table 5a.
And the swivel 4 between the rear ends.

The conventional attaching / detaching device A includes a double-acting hydraulic cylinder 6 for elevating and lowering a counterweight 5 having a cylinder 6 b attached to the rear end of the swivel 4 so that the piston rod is located at a proper position at the rear end. The connecting means 7 is attached between the lower end of the piston rod 6a of the double-acting hydraulic cylinder 6 and the weight mounting table 5a and manually operated to release the connection.

According to the conventional attaching / detaching device A configured as described above, when removing the counterweight 5 from a state in which the counterweight 5 is attached to the rear end of the swivel base 4 (FIG. 8) , first, the telescopic boom 3 is moved to the vehicle. swivel base to face one of the rear
The turn 4 is turned, and a counterweight 5 arranged at the rear end of the turntable 4 is positioned on the vehicle frame 2 between the driver's cab and the turntable 4. Next, the double-acting hydraulic cylinder 6 of the attachment / detachment device A is extended and driven to lower the counterweight 5 on the vehicle frame 2. Then, the connecting means 7 of the attaching / detaching device A is manually released, and the double-acting hydraulic cylinder 6 is reduced. The traveling of the mobile crane is performed by rotating the swivel base 4 so that the telescopic boom 3 faces the front of the vehicle 1 and contracting and lowering the telescopic boom 3. At that time, the counterweight 5 removed from the rear end of the swivel base 4 as described above is left on the vehicle frame 2 or replaced with another vehicle from the vehicle frame 2 by appropriate means. is there. When attaching the counterweight 5 to the rear end of the swivel 2, the reverse operation is performed.

[0005] In FIGS. 7 to 9, a pair of left and right attachment devices A are attached to the rear end of the swivel 2.

A conventional counterweight attaching / detaching device for a mobile crane constructed in this manner is a double-acting hydraulic cylinder in which a lifting / lowering drive of the counterweight 5 when attaching / detaching the counterweight 5 is attached to the rear end of the swivel 4. 6, the operation of releasing the connection of the connecting means 7 in the attaching / detaching device A must be directly performed manually, and there is a problem that the operation is troublesome and dangerous.

[0007]

[Problems to be solved by the invention]
It is an object of the present invention to provide a device for attaching and detaching a counterweight of a mobile crane, which can remotely disconnect the connecting means 7 by using power without relying on manual operation.

[0008]

According to the present invention, a counterweight attaching / detaching device for a mobile crane according to the present invention is configured as follows to achieve the above object. A swivel table 4 having a telescoping boom 3 which can be raised and lowered is mounted on a vehicle frame 2 so as to be swivelable, and a weight mounting table 5a is provided at the rear end of the swivel table 4.
And a weight 5b mounted on the weight mounting table 5a
A counterweight 5 for a mobile crane having a counterweight 5 formed of a cylinder and a cylinder 6b with its piston rod 6a positioned at an appropriate position at the rear end of the turntable 4.
, A double-acting hydraulic cylinder 6 for raising and lowering a counterweight, a rod-side engaging member disposed at the lower end of a piston rod 6a of the double-acting hydraulic cylinder 6, and a mounting table-side engaging device disposed on the weight mounting table 5a. Connecting means 7 comprising: a piston rod 6a of the double-acting hydraulic cylinder 6;
A piston rod rotating rod, which is telescopically and non-twistable and penetrates the bottom end wall of the cylinder 6b in an oil-tight and rotatable manner so that its upper end faces outside the bottom end wall; and Piston rod rotation driving means attached to the bottom end of the cylinder 6b and engaged with the upper end of the piston rod rotation rod to rotationally drive the piston rod rotation rod; Characterized in that it is configured to be disengaged by relative rotation of
A lane counterweight attachment / detachment device.

[0009]

The counterweight attaching / detaching device of the mobile crane of the present invention constructed as described above comprises a rod-side engaging member disposed at the lower end of the piston rod 6a of the double-acting hydraulic cylinder 6, and the weight mounting of the counterweight 5. A connecting means 7 including a mounting table side engaging tool disposed on the mounting table 5a is adapted to be disengaged by relative rotation of the two, and the piston rod is driven by a piston rod rotation driving means attached to the bottom end of the cylinder 6b. By rotating the piston rod 6a via a rotating rod, the connecting means 7
By rotating the rod-side engaging member, the connecting means 7 can be remotely engaged and disengaged using power.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a counterweight attaching / detaching apparatus for a mobile crane according to the present invention will be described below with reference to FIGS. The attachment / detachment device for the counterweight according to the present invention is different from the conventional one shown in FIGS. 7 to 9 in that a structure for rotating and driving the piston rod 6a is added to the double-acting hydraulic cylinder 6, and a connecting means. 7 is characterized in that the configuration of FIG. 7 is changed. Therefore, FIG.
Conventional mounting and dismounting of the counterweight shown in FIG. 9 and described above.
The reference numerals used in the description of the device and the description thereof, except for these two points, are also used as they are in the following description.

FIGS. 1 and 2 correspond to FIGS. 8 and 9, respectively, used in the description of the prior art.
The lower end portion of the double-acting hydraulic cylinder 6 for elevating and lowering the counterweight, with the cylinder 6b mounted so that a is positioned below, forms a connecting means 7 in cooperation with a mounting table side engaging tool 7b described later. The rod-side engaging member 7a is attached. The coupling means 7 is adapted to be engaged and disengaged by the relative rotation of the rod side engaging member 7a and the mounting table side engaging member 7b.

The specific configuration of the connecting means 7 will be described with reference to FIG. 5. The rod-side engaging member 7a of the connecting means 7 is attached to the lower end of the piston rod 6a in the radial direction (radial direction) of the piston rod 6a. And a pair of right and left engaging claws 8 extending to the mounting table, and a mounting table side engaging member 7b of the connecting means 7 is provided with an end plate 10 on an upper part of a cylindrical portion 9 protruding above the weight mounting table 5a. The rod-side engaging member 7
a claw passing portion 1 for passing the pair of right and left engaging claws 8
It is composed of a head plate 10 provided with 1, 11. The claw passing portions 11, 11 of the mounting base side engaging tool 7b are arranged such that the mounting base side engaging tool 7b and the rod side engaging tool 7a are at a predetermined relative rotation position, and the engaging claws 8, 8 are allowed to pass. Then, the engaging claws 8, 8 are moved to the pawl elapse portions 11,
11, the rod-side engaging member 7a is relatively rotated by approximately 90 ° with respect to the mounting table-side engaging member 7b in a state where the engaging members 7a and 7b are positioned in the cylindrical portion 9. Are to be combined.

The double-acting hydraulic cylinder 6 is shown in FIGS.
It will be described based on. The double-acting hydraulic cylinder 6 is mounted in a proper position at the rear end of the swivel 4 so that the piston rod 6a is positioned downward, as in the prior art. In FIG. 3, 6c
Is a piston fixed to the upper end of the piston rod 6a. Reference numeral 12 denotes a piston rod rotating rod which is telescopically and non-twistably engaged with the upper end of the piston rod 6a of the double-acting hydraulic cylinder 6 directly or via the piston 6a. The upper end of the piston rod rotating rod 12 penetrates the bottom end wall of the cylinder 6b in an oil-tight and rotatable manner and projects outside the bottom end wall. 13 is
It is a piston rod rotation driving means attached to the bottom end of the cylinder 6b, and its output shaft is connected to the upper end of the piston rod rotation rod 12. The rotation driving force of the piston rod rotation driving means 13 is transmitted to the piston rod 6a via the piston rod rotation rod 12, and drives the piston rod 6a to rotate with respect to the cylinder 6b. The rotational drive of the piston rod 6a rotates the rod-side engaging member 7a of the connecting means 7. The rotation of the piston rod 6a is controlled by the piston 6
This is permitted by the sliding of the packing between c and the cylinder 6b and between the piston rod 6a and the cylinder 6b.

Next, a pair of left and right double-acting hydraulic cylinders 6
6 and a drive control circuit for the piston rod rotation driving means 13 and 13 arranged in the double-acting hydraulic cylinders 6 and 6, respectively, will be described with reference to FIG. In FIG. 6, reference numeral 14 denotes a solenoid-operated directional switching valve having a pair of control ports connected in parallel to corresponding upper and lower oil chambers of a pair of left and right double-acting hydraulic cylinders 6, 6, respectively. 15 is
This is a double-acting hydraulic cylinder control switch that controls the energization of the extension operation side solenoid 14a and the reduction operation side solenoid 14b of the direction switching valve 14, and is mounted in the cab arranged on the swivel 4 of the mobile crane. .
Reference numeral 16 denotes a solenoid-operated directional switching valve having the pair of control ports connected in parallel to the corresponding ports of the pair of left and right rotation driving means 13, 13. Reference numeral 17 denotes a rotation drive means control switch for controlling energization of the forward operation solenoid 16a and the reverse operation solenoid 16b of the direction switching valve 16, and is provided in an operator cab arranged on the swivel 4 of the mobile crane. It is attached.

Reference numeral 18 denotes a double-acting hydraulic cylinder control switch 15 and an extension operation side solenoid 14 a of the directional control valve 14.
The relay switch 18 is provided in an electric circuit for connecting the turntable 4 to a position where the turntable 4 is turned and the counterweight 5 is attached and detached (the rear end of the turntable 4 is connected to the driver's cab of the vehicle). (The swivel position located between the swivel table 4)
The electric circuit is connected in conjunction with the operation of the limit switch 19 that detects the presence of the electric circuit. The limit switch 19 is constituted by a limit switch disposed between the swivel base 4 and the vehicle frame 2, or
And a limit switch for detecting a fixed state of a turning fixing means (not shown) for fixing a turning position of the turning table 4 to a counterweight attaching / detaching position, which is mounted between the vehicle and the vehicle frame 2.

Reference numeral 20 denotes a rotation drive unit control switch 17
A relay switch interposed in an electric circuit for connecting a common terminal and a power supply, and the relay switch 20 includes:
The left and right double-acting hydraulic cylinders 6 and 6 are in the most extended state (positions at which the respective connecting means 7 can engage.
The electric circuit is connected in conjunction with the operation of the limit switches 21 and 21 for detecting a state at a lower position after passing through the first and the first. Limit switches 21 and 2
1 is attached to the left and right double-acting hydraulic cylinders 6, 6, respectively.

Next, the operation will be described. When removing the counterweight 5 from a state in which the counterweight 5 is attached to the rear end of the swivel base 4 (FIG. 1), the swivel base 4 is first turned so that the telescopic boom 3 faces the rear of the vehicle 1. A counterweight 5 arranged at the rear end of the vehicle is positioned on the vehicle frame 2 between the driver's cab and the turntable 4. In this state, the relay switch 18 is connected, so that the double-acting hydraulic cylinders 6, 6 can be extended and driven. Next, the double-acting hydraulic cylinder control switch 15 is operated to extend the double-acting hydraulic cylinders 6, 6, and the counterweight 5 is lowered and mounted on the vehicle frame 2. In this state, since each of the double-acting hydraulic cylinders is in the most extended state, the relay switch 20 is connected, and the forward and reverse driving of the piston rod rotation driving devices 13, 13 is possible. Next, the rotation drive means control switch 17 is operated to rotate the piston rod 6a and the rod-side engaging member 7a disposed at the lower end of the piston rod 6a, thereby releasing the connection of the connection means 7. Thereafter, the directional control valve 14 is operated by the double-acting hydraulic cylinder control switch 15 to reduce the size of the double-acting hydraulic cylinders 6 and 6.

The traveling of the mobile crane is performed by the telescopic boom 3
Is turned and the telescopic boom 3 is reduced and laid down so as to face the front of the vehicle 1. At that time, the counterweight 5 removed from the rear end of the swivel 4 as described above is
That is, the vehicle is left mounted on the vehicle frame 2 or replaced with another vehicle from the vehicle frame 2 by an appropriate means. When attaching the counterweight 5 to the rear end of the swivel 2, the reverse operation is performed.

[0019]

Advantages of the Invention The counterweight attaching / detaching device of the mobile crane according to the present invention, which is constructed and operated as described above, drives the lifting of the counterweight 5 when the counterweight 5 is attached and detached after the swivel 4 as in the prior art. While being able to be performed by the double-acting hydraulic cylinder 6 attached to the end, the connection of the connecting means 7 disposed between the double-acting hydraulic cylinder and the counterweight can be remotely performed using power. Therefore, there is an effect that the disconnection operation can be performed easily and safely.

In the above-described embodiment, in the double-acting hydraulic cylinders 6 and 6 and in the drive control circuits of these double-acting hydraulic cylinders 6 and 6, the turning position of the swivel table 4 is determined by the position (swing A relay switch 18 connected in conjunction with the operation of a limit switch 19 for detecting that the rear end of the platform 4 is at a turning position located between the driver's cab of the vehicle and the rotating platform 4). The extension drive of the double-acting hydraulic cylinders 6 and 6 (the downward drive of the counterweight 5) is enabled only when the turning position of the swivel table 4 is at the counterweight attachment / detachment position. Since the lowering drive of the counterweight 5 is restricted in other cases, the safety is further enhanced.

In the above-described embodiment, the double-acting hydraulic cylinders 6 and 6 are in the most extended state (the positions at which the connecting means 7 can be engaged ... the engaging pawls) in the control circuit of the piston rod rotation driving means 13 and 13. A limit switch 2 for detecting a state in which 8, 8 is at a lower position passing through the claw passage portions 11, 11).
Relay switch 20 connected in conjunction with the operation of 1, 21
And the coupling rods 7, 13 can be uncoupled by the piston rod rotation driving means 13, 13 only when the double-acting hydraulic cylinders 6, 6 are at the most extended position (the lowered position of the counterweight 5). However, by doing so, the operation of releasing the connection of the connecting means 7 in the raised state of the counterweight 5 (the state of being mounted on the rear end of the swivel base 4) is restricted, so that the operation is further safer.

[Brief description of the drawings]

FIG. 1 is a side view of a rear end of a swivel base of a mobile crane equipped with a counterweight attaching / detaching device according to the present invention.

FIG. 2 is a rear view of FIG. 1;

FIG. 3 is an explanatory cross-sectional view of a double-acting hydraulic cylinder portion of the attachment / detachment device of the present invention.

FIG. 4 is a sectional view taken along line XX of FIG. 3;

FIG. 5 is an explanatory view of a connecting means portion of the attaching / detaching device of the present invention.

FIG. 6 is an explanatory diagram of a control circuit of the detachable device of the present invention.

FIG. 7 is an explanatory view of a mobile crane.

FIG. 8 is a side view of a rear end portion of a swivel base of a mobile crane equipped with a conventional counterweight attaching / detaching device.

FIG. 9 is a rear view of FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle 2 Frame 3 Telescopic boom 4 Turning table 5 Counter weight 5a Weight mounting table 5b Weight 6 Double acting hydraulic cylinder 6a Piston rod 6b Cylinder 7 Connecting means 7a Rod side connecting tool 7b Mounting base side connecting tool 12 Piston rod rotating rod 13 Piston Rod rotation drive means

Claims (1)

(57) [Scope of request for utility model registration] A swivel having a telescoping boom that can be raised and lowered is mounted on a frame of a vehicle so as to be swivelable, and a weight mount is mounted on a rear end of the swivel and the weight mount is mounted on the weight mount. A counterweight attachment / detachment device for a mobile crane in which a counterweight made of a weight is detachably attached, and the cylinder is attached so that the piston rod is located at a proper position at the rear end of the swivel base. A double-acting hydraulic cylinder for raising and lowering the counterweight, a connecting means comprising a rod-side engaging member disposed at a lower end portion of a piston rod of the double-acting hydraulic cylinder and a mounting table-side engaging device disposed on the weight mounting table; It is telescopically and non-twistably engaged with the piston rod of the double acting hydraulic cylinder, and penetrates the bottom end wall of the cylinder in an oil-tight and rotatable manner. The piston rod rotating rod whose upper end is exposed outside the bottom end wall, and the piston rod rotating rod attached to the bottom end of the cylinder engages with the upper end of the piston rod rotating rod to rotate the piston rod rotating rod. A movable piston crane , wherein the coupling means is configured to be disengaged by a relative rotation of the rod-side engaging member and the mounting table-side engaging member . Counter weight
Detachable device.