JP3271035B2 - Crane weight counterweight attachment / detachment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-propelled crane called an all terrain crane capable of traveling at high speed on rough terrain or on a road, and a counterweight attachment / detachment device for a crane vehicle such as a truck crane near the crane.

[0002]

2. Description of the Related Art Conventionally, a counterweight attachment / detachment device for a crane truck corresponds to a counterweight attachment portion of a swivel base when the boom on the swivel base attached to the rear part of the vehicle body is directed backward.
Since a receiving stand for positioning and supporting the counterweight to be pivotally mounted on the turntable so as to be mounted thereon is mounted on the vehicle body, and the counterweight on the receiving table is lifted and mounted on the mounting portion on the turntable side. Arms and brackets for lifting the counterweight must be protruded from the swivel to the receiving side, and the maximum boom length or the maximum ground lift is limited by the vehicle length when the crane truck is traveling on the road. Is done.

In order to avoid this, Japanese Patent Application Laid-Open No. 2-27679
As shown in Japanese Patent Publication No. 7, the base pivot portion of the boom and the winding drum storage case behind it are mounted on the upper part of the swivel table, and the rear wall of the winding drum storage case is used for lifting a counterweight. Although an invention with an arm is known, in order to increase the maximum ground lift as much as possible within the limit of the length of the vehicle, a winding drum housing is arranged adjacent to the boom base pivot portion. However, it is unavoidable that the maximum boom length is reduced according to the amount of protrusion of the arm at the retracted position, and if the lifting mechanism for mounting and dismounting the counterweight is operated only by the crane operator, the operation preparation is ready. Not only is it complicated and easy to get tired, but also there is a risk that a safety problem may occur when the counterweight is connected to or separated from the tip of the arm.

In recent years, in large-scale construction work at a vast work site associated with the implementation of a regional development project, it is desired to improve the traveling speed and turning performance of a crane vehicle on uneven terrain, and a function to prevent a capsizing. However, for this purpose, it is necessary to at least reduce the weight of the upper object including the boom and the swivel base and lower the center of gravity.

However, since it is difficult to reduce the weight of the boom in order to maintain its strength, a winding drum storage case having a relatively small weight in comparison with the volume is attached to the upper portion of the swivel table adjacent to the back of the boom base. By mounting a heavy counterweight removably below the winding drum housing, it is necessary to reduce the size of the swivel base and lower the center of gravity. This is because even if the lifting capacity is remarkably large and a crane truck that has to be removed from the vehicle body during transportation on the road and transported separately must be attached to the vehicle body when moving within a vast work site. By reloading the counterweight on the pedestal at the front of the vehicle body and fixing the counterweight to the pedestal by appropriate means, it is possible to travel while maintaining the ground pressure of the steered wheels at the required pressure. Because it is normal.

[0006]

The problem to be solved is that the maximum lifting height of the crane is reduced by the protrusion of the lifting mechanism for attaching and detaching the counterweight from the housing of the winding drum to the rear, and
The preparation of the lifting mechanism is complicated, and if only the crane operator safely performs the preparation, it is difficult to move the crane truck quickly between the loading and unloading work sites in the vast work site, and the efficiency of the loading and unloading operation is reduced. It is a point to be made.

[0007]

According to the present invention, a lower link of a four-bar link mechanism operable in a vertical plane in the front-rear direction is provided at the bottom of a cavity of a counterweight mounting portion of a swivel table corresponding to a receiving table. A cradle-side end of an upper link that is fixedly connected to the lower link to form a vertical link on the cradle side of the lower link, and a vertical driving link shorter than the telescopic cylinder at a reduced position. And a pivoting device for a driving link capable of moving the hooked upper link between a storage position in the cavity and a projecting position where a part of the upper link projects to the receiving table side. The hook is configured to be engaged with and disengaged from a hook engaging portion which is recessed in a side wall surface of the turntable of the counterweight on the pedestal in the middle of the expansion and contraction of the telescopic cylinder, and the hook on the pedestal is extended when the telescopic cylinder is extended. As the counterweight is lifted in a substantially vertical position at the mounting position on the swivel, Constitute a counterweight to the side "shape, the most important feature in that a means capable of fixing the telescopic cylinder in the extended position.

[0008] The extension position fixing means of the telescopic cylinder is provided so that, when the telescopic cylinder is in the extended position, the restricting arm abutting and engaging with the lower end of the cylinder can be rotated toward the driving link. The lower end is pivoted on the lower link coaxially with the lower end of the piston rod of the telescopic cylinder, and the counterweight is attached to the turntable so that the driving link is interlocked with the driving link rotating device via the restraining arm. The link between the restraining arm abuttingly engaged with the lower end of the cylinder and the driving link is interlocked by a telescopic link having a maximum length, and the telescopic link is constantly extended and urged by a force smaller than the conduction force of the driving link rotating device. When the upper arm is retracted from the extended position, the restraining arm is configured to rotate prior to the position where the telescopic cylinder is not reduced, and the upper link in the retracted position is extended. , To stop at the position where the restraining arm abutting engagement with the cylinder bottom, preferably provided a difference in turning radius between the restraining arm and driving link by driving link pivot system.

In this case, the operation lever of the driving link rotating device mounted on the swivel base is configured to be restrained at the retracted position and the extended position of the upper link, respectively, and between the operation lever and the telescopic link. A telescopic rod that is constantly contracted and urged by a spring having a spring constant larger than the spring constant of the extension urging spring of the telescopic link is inserted into the transmission path, and the operating lever in the extended position is stored in the retracted position. When the difference between the two spring constants is set so that the restraining arm rotates to a position where the contraction arm does not hinder the contraction of the telescopic cylinder, the operation becomes easier.

[0010]

Embodiment An embodiment of the present invention applied to an all terrain crane shown in FIG. 12 will be described below. In the figure,
Reference numeral 1 denotes a swivel that is rotatably mounted on a rear portion of the vehicle body 2 around 0-0 as a rotation axis. 3 denotes a base pivot portion of a multi-stage telescopic boom 4 provided at an upper portion of the swivel. 5 denotes a base of the boom. FIG. 3 shows a winding drum housing provided adjacent to the end pivot portion 3, and an auxiliary counterweight 7 serving as a mounting portion of the counterweight 6 is provided vertically below a rear portion of the winding drum storage 5. At a work site on a vast uneven ground, the rear wall is attached in a substantially continuous manner, and as shown in the figure, the telescopic boom 4 fixed substantially horizontally as shown in FIG.
Pressing and fixing the counterweight 6 to the cradle 8 on the vehicle body,
The two counterweights 6, 7 adjust the ground pressure of each wheel of the multi-wheeled vehicle to travel. Reference numeral 9 denotes a derrick cylinder for raising and lowering the telescopic boom 4, and reference numeral 10 denotes front and rear outriggers.

FIG. 4 shows that the swivel table 1 is shifted from the state shown in FIG.
FIG. 5 is a front view showing a state in which the counterweight 6 is attached to the auxiliary counterweight 7 after turning, and FIG. Are mounted symmetrically in a space 11 provided in the auxiliary balance weight 7 symmetrically with respect to the front-rear vertical plane AA including the swivel axis 0-0 of the swivel table 1, and the balance weight at that time. No. 6 front wall is 0
−0, and is an arc surface having a radius R centered on −0.
The rear wall and the front wall of the auxiliary counterweight 7 are also concentric arc surfaces,
As shown in FIG. 12, the clearance required for turning the turntable 1 on which the auxiliary counterweight 7 is mounted is reduced with respect to the counterweight 6 fixed on the receiving table 8 by appropriate means. Reference numeral 12 denotes a groove provided in a vertical portion of the counterweight 6 so that the horizontally extending telescopic boom 4 and the mounting portion of the derrick cylinder 9 are fitted.

FIG. 1 is a sectional view taken along line WW of FIG. 4, and a four-bar link mechanism operably provided in a vertical plane in the front-rear direction in a space 11 of the auxiliary counterweight is provided with a bottom in the space. A pair of left and right bracket-shaped lower links 13 (see FIG. 6) fixed to the lower end, an inverted telescopic cylinder 15 having a piston rod lower end pivotally connected 14 between the bracket-shaped lower links at the end of the receiving stand 8 side, On the opposite side of the link, a pair of left and right driving links 17 pivotally connected at their lower ends 16 between the bracket-shaped lower links, and a pair of right and left pivoting front and rear 18, 18 at the upper end of the telescopic cylinder 15 and the upper end of the driving link 17, respectively. The upper link 20 is fixed integrally by a connecting beam 20a. When the driving link 17 is rotationally urged clockwise by a driving link rotating device described later, the shaft 21 mounted between the upper portions of the left and right driving links and the shaft 22 mounted on the rear end of the lower link 13 move idly. Engagement with both ends of the long hole of the link 23 holds the pivot 19 in the extended position of the upper link 20.

Numeral 24 designates a hook integrally provided at the overhanging end of the upper link 20. Since the telescopic cylinder 15 at the contracted position is longer than the driving link 17, the hook 24 is made to expand and contract by the telescopic cylinder. Draws an inclined arc locus M projecting forward and upward of the vehicle body around the pivot shaft 19 at the base end of the upper link 20 at the overhang position, and the hook 24 when the telescopic cylinder is extended is positioned at the counterweight mounting position shown in FIG. Further, when the telescopic cylinder is contracted, the hook 24 is at the counterweight release position shown by the chain line in FIG. Also, the front and rear positioning pieces 8a, 8b of the receiving table 8
4 are provided on the lower surface of the counterweight, respectively.
(See FIG. 1) as shown by a chain line in FIG.
The hook engaging portion 25 of the counterweight 6 supported above is located at an intermediate position B of the arc locus M.

The hook engaging portion 25 is rotatably connected to a shaft on which both ends of a hook 24 are engaged and disengaged from a shaft supported at both ends by a metal fitting 26 fixed in a recess 6c on the side surface of the turntable of the counterweight 6. The hook engaging portion 25 is provided so that the counterweight 6 in a "side" shape is lifted in a substantially vertical posture.

According to the above configuration, by providing appropriate means for fixing the telescopic cylinder 15 in the extended position, the outer wall of the side-shaped counterweight 6 on the revolving base is substantially brought into contact with the auxiliary counterweight 7. Thus, the counterweight can be fixed to the mounting position shown in FIG. Therefore, when lowering the counterweight 6 onto the cradle 8, the telescopic cylinder 15 is slightly extended to release the extension position fixing means, and then the telescopic cylinder is contracted to thereby reduce the counterweight 6. Is lowered onto the receiving stand, the hook 24 is disengaged from the hook engaging portion 25, and then the driving link 17 is
The hook and the four-bar link mechanism can be stored in the space 11 by being rotated counterclockwise by the rotating device. When the counterweight on the receiving table is attached to the swivel table 1, Conversely, after the driving link 17 is rotated clockwise by the rotation device to extend the four-bar link mechanism to the extended position, the telescopic cylinder is extended, and the telescopic cylinder is fixed at the extended position. It's clear what we need to do.

However, when traveling on uneven terrain, the telescopic cylinder 15
In order to completely prevent the contraction of the telescopic cylinder, and to fix the counterweight 6 at the mounting position on the swivel table, the extension position fixing means of the telescopic cylinder should be controlled separately from the telescopic control of the telescopic cylinder. Therefore, it is preferable to control the extension position fixing means of the telescopic cylinder in conjunction with the rotation device of the driving link.

In the illustrated embodiment, a pair of left and right restraining arms 27, 27, which are fixedly opposed to each other at a position where the telescopic cylinder 15 is extended, with stopper pieces 27a abuttingly engaging with the lower end of the cylinder as shown in FIG. Lower end, lower link 13
Outside the piston, the piston rod 15a of the telescopic cylinder
The two constraining arms 27, 27 are pivotally mounted 14 coaxially with the lower end.
In between, a connecting rod 27b is fixed so as to be able to rotate toward the driving link 17, and upper ends of a pair of arms 28 and 29 fixed to the inner restraining arm 27 as shown in FIGS. And a pair of arms 30 and 31 fixed to the driving link 17 are connected by a telescopic link 32 which is constantly extended and urged by a force smaller than the conduction force of the driving link rotating device. Is the driving link 17 via the telescopic link 32.
Is rotated.

The driving link rotating devices respectively mounted in the spaces 11 on both sides of the auxiliary counterweight 7 are provided at both ends of an interlocking shaft 42 (see FIG. 7) rotatably mounted on the bottom of the auxiliary counterweight. The first transmission lever 33 fixedly supported by the
2 is a first transmission lever 33 as shown in FIGS.
A bolt 35 connected to the piece 3 through a link 34 is slidably inserted into opposed pieces 36 and 37 having an oval shape.
6 is pivotally supported between the arms 28 and 29 concentrically with the circular arc surface, and the other piece 37 is connected to the driving link 1
7 between the arms 30 and 31 so as to be concentric with the shaft 21 of
9, a compression spring 40 is sandwiched between the two pieces 36 and 37, and a double nut 41 in which the arc face of the piece 36 is screwed into the bolt head 35a and the arc face of the other piece 37 is screwed into the bolt 35.
In the state of FIG. 1 or FIG. 8, the telescopic link 32 has the maximum length,
7 prevents the telescopic cylinder 15 from contracting.

In order to lower the counterweight 6 onto the cradle 8, the telescopic cylinder 15 is slightly extended from the state shown in FIG.
When the driving link rotating device is operated to rotate the extension link 3 in the counterclockwise direction, the compression link
2 is retracted as shown in FIG. 2, and the restraining arm 27 is pivoted to a position where the contraction of the telescopic cylinder 15 is not hindered. After the counterweight is supported by the cradle 8, the hook 24 gets over the hook engaging portion 25 as the telescopic cylinder is reduced, so that the driving link is moved counterclockwise by the conductive force of the rotating device. When the operating lever of the driving link rotating device is restrained at the storage position by appropriate means,
The driving link 17 is the upper link 20 and the connecting beam 20
By the action of gravity of the telescopic cylinder engaged via a, the telescopic cylinder rotates to the retracted position shown in FIG. 3, and at the same time, the telescopic link 32 is extended and cut to rotate the restraining arm 27 to the position shown in FIG. Of course, an appropriate stopper for holding the driving link 17 in the storage position may be provided on the lower link side.

Also, while the driving link 17 rotates from the position shown in FIG. 3 to the position shown in FIG. 1, the driving link for the lower link 13 is moved so that the restraining arm 27 rotates from the position shown in FIG. Since there is a difference in the radius of rotation of the telescopic link connecting portions (39, 38) between the arm 17 and the restraining arm 27, when the counterweight 6 on the receiving table 8 is attached to the swivel 1, the driving link rotation is required. When the telescopic cylinder 15 is extended after the hooked upper link is extended to the extended position by the device, the restraining arm 27 automatically engages with the lower end of the cylinder.

However, in the above-described embodiment, when the counterweight 6 is lowered onto the pedestal, the driving link rotating device and the telescopic cylinder control device must be operated at the same time. In the conduction path between the operating lever 45 of the moving device and the telescopic link 32, a telescopic rod constantly contracted and urged by a spring having a spring constant larger than the spring constant of the extension urging spring of the telescopic link. It can be solved by inserting.

As shown in FIG. 11, the operation lever 45 is pivotally mounted at the base end thereof to the side of the crane cab 46 of the swivel 1 so as to be operable through a window thereof. It is in the position shown by the solid line. An auxiliary lever 49 pivotally attached to the middle of the operation lever 45 is always urged to rotate counterclockwise by a spring (not shown), and the operation side end of the auxiliary lever 49 is a guide attached to the operation lever. The auxiliary lever is rotatable upward in the frame 50, and the other end of the auxiliary lever is engaged with a first stopper 51 attached to the swivel base to restrict the downward rotation of the operation lever. , Operation lever 45
And the grip of the auxiliary lever 49 (left end in the figure) together,
The other end of the auxiliary lever 49 is detached from the stopper 51 so that the operation lever 45 can be pivoted downward, and if the hand is released from the auxiliary lever 49 of the operation lever 45 pivoted to the position shown by the dashed line, the auxiliary The engaging member 52 of the lever is engaged with the second stopper 53 to restrain the operation lever 45 at the storage position of the upper link 20.

The arm 45a at the base end of the operation lever is interlocked and connected via a pushable wire 54 to a second transmission lever 56 whose upper end is pivotally mounted 55 in the space 11 of the auxiliary counterweight 7. A telescopic rod 5 having at one end a long hole 58a into which a pin 57 implanted at the lower end of a second transmission lever 56 is slidably engaged.
8 is pivotally connected 59 to the upper end of the first transmission lever 33, and a compression for extending and urging the extension link 32 is provided between a lower portion of the second transmission lever 56 and the other end of the extension rod 58. Spring 4
A tension spring 60 having a spring constant larger than 0 is stretched so that the pin 57 is engaged with the right end of the elongated hole 58a.

For this reason, the operation lever 45 shown by the solid line in FIG.
Is rotated to the storage position shown by the chain line, the pin 57 at the lower end of the second transmission lever slides along the long hole 58a to the left in the figure to increase the elasticity of the tension spring 60, whereas the hook of the upper link While the hook 24 is engaged with the hook engaging portion 25 of the counterweight, the driving link 17 is held at the extended position.
The compression spring 40 of the telescopic link is compressed by the elastic force of the tension spring 60, and the restraining arm 27 rotates to a position where the contraction of the telescopic cylinder 15 is not hindered, as shown in FIG. As a result, the counterweight 6 is supported by the cradle 8 as described above, and the hook 2
4 comes off, the extension rod 58 is extended by the elasticity of the tension spring 60.
Is contracted, the restraining arm 27 rotates to the position shown in FIG. 3, and the driving link 17 rotates to the retracted position shown in FIG.
Can be controlled to expand and contract, and the operation becomes easy.

The engagement between the hook 24 of the four-bar link mechanism and the hook engaging portion 25 of the side-shaped counterweight 6 and the turntable side of the counterweight 6 with respect to the outer wall of the auxiliary counterweight 7 The case in which the counterweight is attached to the auxiliary counterweight by contact with the outer wall has been described. However, the lower end of the telescopic cylinder 15 and the restraint arm 27 in the extended position in the extended state when the counterweight 6 is mounted are described.
When the gap provided between the counterweight and the auxiliary counterweight is increased so that the telescopic cylinder can be further extended to release the engagement with the cylinder, as shown in FIGS. 4 and 5, The positioning means for the balance weight, which is composed of a hole 43 recessed in the bottom surface of the auxiliary balance weight 7 and a projection 44 fixed on the bottom side of the balance weight 6 so as to fit in the hole 43, is provided on the auxiliary balance weight. It is preferable that the counterweight is provided so as to engage the male and female at the same time when the counterweight is mounted.

[0026]

As described above, the present invention utilizes a four-bar link mechanism in which the vertical link on the receiving table side is formed in a telescopic cylinder, and the hook is fixedly supported on the rotating table on the turning table side. It is constructed so that the hook which can be engaged and disengaged with the hook engaging portion which is recessed on the side wall surface of the swivel of the counterweight of the `` side surface on the receiving stand '' and the lifting and lowering with respect to the mounting portion is performed. When the crane truck is traveling at the construction site, there is no risk that the lifting mechanism for attaching and detaching the counterweight will protrude from the back of the bobbin housing, and the length of the telescopic boom during traveling, that is, the maximum ground lift can be increased compared to the past. In addition, since time and man-hours are not required for preparing the operation of the lifting mechanism, it is possible to quickly move the crane truck between the respective loading / unloading work places, and it is possible to improve the loading / unloading work efficiency. .

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional side view (a cross-sectional view taken along line WW of FIG. 4) illustrating a state in which a counterweight is mounted on a swivel table.

FIG. 2 is a vertical sectional side view showing a state in which a counterweight is being removed from a swivel base.

FIG. 3 is a vertical sectional side view showing a storage state of the counterweight attachment / detachment device.

FIG. 4 is a front view of a counterweight attached to the swivel.

FIG. 5 is a plan view of FIG. 4 excluding a winding drum housing;

FIG. 6 is a sectional view taken along line XX of FIG. 1;

FIG. 7 is a view as viewed in the direction of the arrow Z in FIG. 1 except for a counterweight.

FIG. 8 is an enlarged sectional view taken along line VV of FIG. 7;

FIG. 9 is a cross-sectional plan view of a main part of FIG. 8;

FIG. 10 is an enlarged sectional view taken along line YY of FIG. 1;

FIG. 11 is a side view of the swivel base near the crane cab.

FIG. 12 is a side view schematically showing a crane vehicle in a traveling state.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 swivel base 2 body 4 telescopic boom 5 winding drum storage case 6 counterweight 7 counterweight mounting part (auxiliary counterweight) 8 receiving table 11 vacant space 13 lower link 15 telescopic cylinder 17 driving link 20 upper link 24 hook 25 Hook engaging portion 27 Restraining arm 32 Telescopic link 33 First transmission lever 34 Link 40 Compression spring 45 Operating lever 54 Pushable wire 56 Second transmission lever 58 Telescopic rod 60 Tension spring

Claims (3)

(57) [Claims] 1. A bobbin housing which is attached to a rear end of a vehicle body and which is attached to a rear end of a vehicle body, a base end pivot portion of a boom facing forward, and an adjacent bobbin housing case behind the base member. And the vertical rear wall of the counterweight mounting part of the swivel base is approximately connected, and the counterweight mounted on this can be swiveled by the swivel base, corresponding to the counterweight mounting part when the boom is turned backward. A crane truck with a receiving stand positioned and supported on the vehicle body, and four operable in the vertical plane in the front-rear direction on the bottom of the space inside the counterweight mounting part of the swivel base corresponding to the receiving stand The lower link of the rod link mechanism is fixedly attached, and the lower link is connected to the lower link via a telescopic cylinder forming a vertical link on the receiving side thereof and a vertical driving link shorter than the telescopic cylinder at the reduced position. A hook is integrally provided on the terminal on the receiving side of the link, and the upper link with the hook is connected to the space. A pivoting device for a driving link which is movable between a storage position and an overhanging position where a part thereof protrudes toward the cradle side; So that it can be engaged with and disengaged from the hook engaging portion recessed in the side wall surface of the swivel base, and when the telescopic cylinder is extended, the counterweight on the cradle can be lifted in a substantially vertical posture at the mounting position on the swivel base. And a means for fixing the telescopic cylinder in the extended position by providing the counterweight in a "side" shape. 2. The telescopic cylinder extension position fixing means according to claim 1, wherein, in the extension position of the inverted telescopic cylinder, the restraining arm abuttingly engaging the lower end of the cylinder can be turned to the driving link side. As described above, the lower end of the restraining arm is pivotally mounted on the lower link coaxially with the lower end of the piston rod of the telescopic cylinder, and the swivel base is connected to the driving link rotating device via the restraining arm. In a state where the counterweight is attached to the cylinder, the link between the restraining arm abuttingly engaged with the lower end of the cylinder and the driving link is linked by a telescopic link having a maximum length, and the telescopic link is determined by the transmission force of the driving link rotating device. When the upper link is retracted from the extended position by constantly expanding and biasing with a small force, the restraining arm is configured to rotate prior to a position that does not hinder the contraction of the telescopic cylinder, and H When extending the hooked upper link, a difference is provided in the rotation radius of the telescopic link connecting portion between the driving link and the restraining arm so that the restraining arm stops at the position where the restraining arm comes into contact with the lower end of the cylinder. 3. The device for attaching and detaching a counterweight of a crane truck according to claim 1, wherein: 3. An operation lever of a driving link rotating device attached to a swivel base is configured to be restrained at a storage position and an extended position of an upper link, respectively, and a transmission system between the operation lever and the telescopic link is provided. An extendable rod which is constantly contracted and biased by a spring having a spring constant larger than the spring constant of the extension biasing spring of the telescopic link is inserted into the road, and the operation lever at the extended position is turned to the retracted position. 3. The device according to claim 2, wherein the difference between the two spring constants is set so that the restraining arm rotates to a position where it does not hinder the contraction of the telescopic cylinder when moving.