JP2503011Y2 - Extension control device for outrigger device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an outrigger device used in a crane vehicle or the like.

(Prior Art) Conventionally, in this type of outrigger device, as shown in, for example, FIGS. 9 and 10, there are those that manually perform overhanging and retracting work of the inner cylinder, and in such outrigger device, crane work is performed. An expansion / contraction control device is provided in order to prevent undesired expansion / contraction in the interior and expansion due to acceleration during turning of a crane vehicle.

In these figures, 1 is a vehicle frame of a crane vehicle, 2 is an outer cylinder fixed to the lower portion of the vehicle frame, 3 is an inner cylinder which is fitted in the outer cylinder 2 and is expandable and contractable, 4
Is a leg part, in which a jack is vertically provided at the tip of the inner cylinder 3.

An extension / contraction control device 5 is installed at the tip of the outer cylinder 2.

The expansion / contraction control device 5 has a cam cylinder 6 fixed to the upper surface of the outer cylinder 2, and a lock pin 7 is inserted through the cam cylinder 6.

At the upper end of the lock pin 7, an operation lever 8 is installed in the radial direction, and the lock pin 7 is urged downward by a coil spring 11, whereby the operation lever 8 is moved to the cam barrel 6 The lock pin 7 is brought into close contact with the cam surface formed on the upper end surface of the lock lever 7, and the lock pin 7 is adjusted up and down by the rotation adjustment of the operation lever 8.

On the other hand, a plurality of engagement holes 12 are formed in the upper surface of the inner cylinder 3 below the expansion and contraction control device 5, and the lock pin is held at the retracted position of the inner cylinder 3 with respect to the outer cylinder 2 and an appropriate protruding position. At the position corresponding to the inner end of 7
12 are formed respectively.

Therefore, the operation lever 8 is operated to raise the lock pin 7, and the inner cylinder 3 is manually extended or retracted. After that, the operation lever 8 is operated to lower the lock pin 7, and the inner end of the lock pin 7 is moved. Required engaging hole formed in the inner cylinder 3
It is necessary to immerse the inner cylinder 12, and by performing these operations, the expansion and contraction of the inner cylinder 3 is prevented.

(Problems to be solved by the invention) Recently, in order to automate these operations, it has been attempted to extend and retract the inner cylinder by power using a drive means such as an electric motor. With the driving by the means, it is necessary to lock the inner cylinder that has reached a predetermined position and stop the driving means at the same time.

By the way, in this type of outrigger device, since the expansion / contraction control device including a lock pin or the like is often installed at the distal end portion of the outer cylinder, it is desired that the expansion / contraction control device is not large in size and has a simple structure. .

The present invention has been made under such circumstances, and has a relatively simple structure, and automatically locks the inner cylinder, which has reached a predetermined position by the driving means, to the outer cylinder, and the driving means An object is to provide an expansion / contraction control device for an outrigger device that can be automatically stopped.

(Means for Solving the Problem) In order to achieve such an object, the present invention is directed to an outer cylinder horizontally mounted on a vehicle body frame and an inner cylinder in which the outer cylinder is telescopically fitted and a jack is provided vertically at its tip. And an expansion / contraction drive means for expanding / contracting the inner cylinder relative to the outer cylinder, wherein the outer cylinder is provided with a lock pin that is elastically urged toward the inner cylinder and is capable of advancing and retracting. At the same time, a plurality of engagement holes are formed in the inner cylinder facing the inner end of the lock pin at appropriate intervals, and the lock pin is advanced and retracted so that the inner end of the lock pin is formed in the engagement hole formed in the inner cylinder. In an expansion / contraction control device for an outrigger device that is engaged and disengaged to fix and release the inner cylinder to the outer cylinder, a medium whose physical quantity changes with the engaging operation of the lock pin into the engaging hole is provided. Of the expansion and contraction drive means by the change of the physical quantity of It is intended to stop the work.

(Operation) According to the present invention, the outer cylinder is provided with the lock pin that is elastically urged toward the inner cylinder and is movable back and forth, and the engagement hole is formed in the inner cylinder facing the inner end of the lock pin. In the expansion / contraction control device of this type of outrigger device, a medium whose physical quantity changes with the engaging operation of the lock pin to the engagement hole is provided, and the operation of the expansion / contraction driving means is changed by the change of the physical quantity of the medium. Since it is decided to stop, the expansion / contraction drive means automatically locks the inner cylinder that has reached a predetermined position with the outer cylinder by the lock pin, and the expansion / contraction drive means is automatically operated by the medium as the lock pin is locked. Will be stopped.

Further, there are few components to be added in constructing this expansion and contraction control device, and it is possible to construct relatively easily.
Therefore, the addition of a member to be arranged near the lock pin of this expansion and contraction control device is extremely small, and there is an advantage that the structure in this part is not so complicated.

(Embodiment) The present invention will be described below with reference to an embodiment shown in the drawings. First, the first embodiment will be described with reference to FIGS.

In FIG. 1, 20 is an outrigger device, 21 is an outer cylinder installed in the vehicle width direction of the vehicle body frame of a crane vehicle, and 22 is an inner cylinder that is stored in the outer cylinder 21 and is expandable / contractible. Is.

The inner cylinder 22 is configured to be able to move forward and backward with respect to the outer cylinder 21 by a guide roller 23 and a drive roller 24 installed in the outer cylinder 21, and the inner cylinder 22 has a tip with a leg inside which a jack is installed. The part 25 is provided vertically.

The drive roller 24 in this embodiment is driven by an electric motor 35 as an expansion / contraction drive device in the present invention.

An expansion / contraction control device 26, which will be described later, is fixedly installed on the upper end surface of the outer cylinder 21, and an engaging engagement with a lock pin 28 of the expansion / contraction control device 26 is provided on the upper surface of the inner cylinder 22. The holes 30 are formed so as to correspond to the storage position of the inner cylinder 22 with respect to the outer cylinder 21 and a predetermined projecting position.

The expansion / contraction control device 26 has a cylindrical spring receiver 27 fixed to the upper surface of the outer cylinder 21 by welding (see FIG. 3).

A disk-shaped top plate 27a is fixed to the upper end surface of the spring receiver 27.

A lock pin 28 is provided in the spring receiver 27, and an upper portion of the lock pin 28 projects upward through a through hole 27b formed at the center of the top plate 27a.

The lock pin 28 is installed so as to be rotatable around the central axis O (FIG. 2) with respect to the spring receiver 27 and to be able to move up and down, and between the lock pin 28 and the top plate 27a. A coil spring 29, which is a compression spring, is interposed.

Further, an operation lever 31 is pivotally supported on an upper portion of the lock pin 28, which is located above the spring receiver 27 by passing through the through hole 27b, via a pivot 32 installed in the horizontal direction.

The operation lever 31 has a lever body 31b having an operation grip 31a formed at one end and a tip 31c extending ahead of the pivot 32.

In the operation lever 31, as shown in FIGS. 2 and 3, both the lever main body portion 31b and the tip end portion 31c extend to the outer side in the radial direction from the edge portion of the top plate 27a of the spring receiver 27. It is the size to do.

As shown in FIG. 2, the tip end portion 31c of the operation lever 31 is formed in an arcuate shape protruding laterally, and an upper portion of the lock pin 28 has a U-shape in plan view. An operation member 38 made of a leaf spring is installed.

On the other hand, a first switch 37 is installed on the edge of the top plate 27a of the spring receiver 27, and the tip end of the operation lever 31 is provided.
A second switch 39 is installed on the outer cylinder 21 immediately below 31c.

These switches 37 and 39 are for controlling the electric motor 35 as described later. The first switch 37 switches the rotation direction of the electric motor 35, and the second switch 39 turns on and off the power. This is a switch for performing an on / off operation of the electric motor 35.

Then, the operation lever 31 is elastically urged by the coil spring 29 to the upper surface of the top plate 27a via the lock pin 28, and the operation lever 31 resists the urging force of the third lever to move the third lever. By raising the lever body 31b side with the edge of the top plate 27a as the fulcrum as shown by the phantom line in the figure,
The vertical movement operation of moving the lock pin 28 up and down and the rotation operation of the lock pin 28 around the central axis O are performed at the same time as shown by the phantom line in FIG.

With the operation of the operation lever 31, the operation member 38 faces the operator 37a of the first switch 37 in a state where the operation grip 31a side of the operation lever 31 is lifted.
The switching operation of the first switch 37 is performed by the operation lever 31.

Further, as the operation lever 31 is operated, the tip portion 31
c operates the operator 39a of the second switch 39.

That is, in this embodiment, the second switch 39
The operating element 39a is operated by a displacement operation in the height direction of the tip end portion 31c that changes in association with the height of the lock pin 28 using the operating lever 31 as a medium, and the electric motor 35 as an extension / contraction driving means is intermittently operated. Is controlled.

In this embodiment, the power supply circuit of the electric motor 35 that drives the inner cylinder 22 to project or retract is constructed as shown in FIGS. 4 and 5.

First of all, the power supply circuit 41 of the electric motor 35 includes a power supply 42, a rotation direction control section 43 including the first switch 37, and the second switch 39. The electric motor 35 is connected to the power source 42 via the second switch 39 and the rotation direction control unit 43.

This will be described in detail with reference to FIG. 5 below. On the power source 42 side, a release or emergency stop switch 44 and a second switch 39 are provided.

The release or emergency stop switch 44 has a normally closed contact, and the contact is opened by operating the switch when releasing.

The second switch 39 is also a switch having a normally closed contact, and the contact is opened when the lock pin 28 is retracted into the engagement hole 30, but the lower end of the lock pin 28 is on the upper surface of the inner cylinder 22. In the contacting state, the contact remains closed.

A rotation direction control unit 43 is formed between the second switch 39 and the electric motor 35.

The first switch 37 included in the rotation direction control unit 43 is provided with a first contact 37b and a second contact 37 by the swinging operation of the operator 37a.
One of the c is closed and the other is opened.

In this embodiment, the first contact 37b is a contact for overhanging activation of the inner cylinder 22, and the second contact 37c is a contact for retracting activation of the inner cylinder 22.

Then, relays 45 and 46 are installed on the first and second contacts 37b and 37c, respectively, and the relays 37b and 37c are provided.
When self-contained, it holds itself.

A circuit extending from the relays 45 and 46 to the electric motor 35 side is provided with contacts 44b and 44c which are opened at the same time when the release or emergency stop switch 44 is opened, for controlling the rotation direction of the electric motor 35. Relays 47 and 48 are installed respectively.

This relay 47 has two a contacts 47a,
When the first contact 37b of the first switch 37 conducts, it is energized, these two a contacts 47a are closed, and the electric motor 35 rotates in a direction to drive the inner cylinder 22 in the projecting direction.

The relay 48 also has two a-contacts 48a, and the conduction of the second contact 37c causes the electric motor 35 to rotate in the opposite direction to the above, and similarly drives the inner cylinder 22 in the storage direction.

In the outrigger device 20 having the expansion and contraction control device 26 and the power supply circuit 41 configured as above, when the operation lever 31 is operated, the following operation is performed.

Hereinafter, the case where the operating lever 31 is in the state shown by the solid lines in FIGS. 2 and 3 and the inner cylinder 22 is extended and driven will be described, but the same applies to the case where the inner cylinder 22 is stored and driven.

First, the operation grip 31a of the operation lever 31 is lifted to pull up the lock pin 28 that is immersed in the engagement hole 30.

Along with this, the tip portion 31c of the operation lever 31 presses the operation element 39a of the second switch 39, and the second switch 39a.
Becomes conductive.

Then, in this state, the operation lever 31 is rotated around the central axis O of the lock pin 28 to the position on the overhanging drive side.

With the turning operation of the operation lever 31, the operation member 38 tilts the operator 37a of the first switch 37 and closes the first contact 37b.

In this case, the other second contact 37c remains open.

In this state, the operator of the second switch 39
39a remains pressed down by the tip 31c of the operating lever 31, and at the same time, the first contact 37b is closed and the relay 45
Since it is self-held by, the drive of the electric motor 35 is maintained until the lock pin 28 is engaged with the engagement hole 30 as described later.

With the first contact 37b closed and self-held by the relay 45, a current flows through the relay 47, so that the two a contacts 47a of the relay 47 become conductive.

As a result, the electric motor 35 is supplied with a current having a polarity extending in the driving direction from the power source 42, and the electric motor 35 is
Is driven to rotate in the overhang direction.

In this way, when the driven inner cylinder 22 is extended to the predetermined overhang position, the engaging hole is formed below the lock pin 28.
Since 30 is located, the lock pin 28 that is in sliding contact with the upper surface of the inner cylinder 22 is retracted into the engagement hole 30 by the spring force of the coil spring 29.

Then, with the immersing operation of the lock pin 28, the operating lever 31 is restored from the inclined posture of the imaginary line in FIG. 3 to the horizontal posture shown by the solid line, so that the tip portion 31c is above the second switch 39. And the operator 39a of the second switch 39
Is restored to a horizontal state by the force of a built-in return spring, the power supply circuit 41 to the electric motor 35 is opened, and the overhanging drive of the inner cylinder 22 is automatically stopped.

As described above, in the expansion / contraction control device 26 of the outrigger device 20 of this type, the operation lever 31 interlocked with the engagement / disengagement operation of the lock pin 28 with respect to the engagement hole 30 is provided, and the electric motor 35 is moved by the displacement of the operation lever 31. Because I decided to control intermittently,
The inner cylinder 22 that has reached a predetermined position by the electric motor 35 is automatically locked to the outer cylinder 21 by the lock pin 28.
With the locking operation of 28, the electric motor is
35 is the one that is automatically stopped.

Since only the second switch 39 needs to be added to configure the expansion / contraction control device 26, the number of parts to be added is small, and the configuration can be relatively simple. Therefore, the addition of members to be arranged in the vicinity of the lock pin 28 of the expansion and contraction control device 26 is extremely small, and there is an advantage that the structure in this part is not so complicated.

Further, in this embodiment, the existing operating lever 31
Switch for connecting / disconnecting the expansion / contraction driving means 26 to a position near the
Since the second switch 39 is operated by arranging 39 and displacing the operation lever 31 accompanying the lock operation of the lock pin 28, a required operation can be automatically performed by a relatively simple control circuit. .

Further, in this embodiment, the operator 39 of the second switch 39 is operated by the activation operation of the operation lever 31 as described above.
While a is pressed down by the tip 31c of the operating lever 31, at the same time the first contact 37b is closed and self-held so that the drive of the electric motor 35 is engaged with the engagement hole 30 of the lock pin 28. Since it is maintained up to, the required operation is automatically performed after the start even if the operator does not stay at the position of the operation lever 31.

In the first embodiment, the first switch 37 is installed near the operation lever 31, and the second switch 39 is provided.
Although the present invention has a function of a power-on switch, the present invention can be implemented without operating the first switch 37 with the operation lever 31, and a start switch is installed separately from the second switch 39. Can also be implemented.

Further, the first embodiment described above has been described by using the outrigger device using the electric motor as the extension / contraction drive device. However, as shown in FIG. 6, a hydraulic actuator such as a hydraulic cylinder is used as the extension / contraction drive device. Is also good.

That is, in the modification shown in FIG. 6, 51 is a hydraulic pump and 52 is a double-acting hydraulic cylinder.

The hydraulic cylinder 52 is an outer cylinder 21 and an inner cylinder of the outrigger device 20.
An expansion / contraction drive device that is interposed between the inner cylinder 22 and the outer cylinder 21 so as to extend and store the outer cylinder 21.

A hydraulic circuit 54 having a switching valve 53 is formed between the hydraulic pump 51 and the hydraulic cylinder 52.

The switching valve 53 is a 6-port 3-position switching valve, and the lock pin 28 is manually operated by the operating lever 31 in the same manner as described above.
And the switching operation of the switching valve 53 to the left and right offset positions 55 and 56 at the same time.

Then, when the first offset position 55 is connected to the hydraulic circuit 54, the pressure oil from the hydraulic pump 51 drives the hydraulic cylinder 52 to extend, and the inner cylinder 22 extends. Further, when the second offset position 56 is connected to the hydraulic circuit 54, the hydraulic cylinder 52 is reduced and driven, and the inner cylinder 22 performs the retracting operation.

In this modified example, the hydraulic pump 51 is connected to the switching valve.
Bypass passage 57 to oil tank 58 to pressure oil passage 57 to 53
The bypass valve 57a is formed with a relief valve 57b.

The relief valve 57b normally closes the bypass passage 57a, but opens the bypass passage 57a when the hydraulic pressure in the bypass passage 57a exceeds a predetermined value.

The relief valve 57b is further provided with a control device 61 including an electromagnetic valve 62 and the like, and the control device 61 also functions as follows.

That is, the control device 61 has a power source 63 and a solenoid valve 62, and a circuit reaching the solenoid valve 62 has the second switch 39.
The second switch 39 closes the circuit when the lock pin 28 is inserted into the engagement hole 30.

The solenoid valve 62 is interposed in the vent circuit of the relief valve 57b, and the solenoid valve 58 closes the pipeline from the hydraulic pump 51 to the oil tank 58 at the neutral position in the energized state. By closing the second switch 39, this pipe is communicated.

Therefore, as in the case described above, the lock pin 28 is engaged with the engaging hole 30 when the inner cylinder 22 is extended or retracted.
When the second switch 39 is closed inside, the pressure oil from the hydraulic pump 51 is returned to the oil tank 58 via the relief valve 57b and the electromagnetic valve 62, so that the hydraulic pressure, which is the expansion / contraction driving means, is used. The driving of the cylinder 52 is stopped by the engagement of the lock pin 28.

Next, the second embodiment shown in FIG. 7 will be described.
The second embodiment is different from the modification of the first embodiment described above in the following points, and is otherwise the same.

That is, in the modification described above, the solenoid valve
Although the control device 61 including the second switch 39 and the second switch 39 is used, in this embodiment, instead of these, the second relief valve 71 is used.
A and 71b are used to perform the same function.

In the following, only this difference will be described, and description of the same points will be omitted.

In the second embodiment, the oil tank 58 is branched from the expansion side pressure oil passage 72a and the pressure side pressure oil passage 72b connecting the switching valve 53 and the hydraulic cylinder 52, respectively.
To form conduits 73a, 73b leading to, and these conduits 73a, 73b,
The hydraulic pressure is slightly higher than the hydraulic pressure of the outrigger device 20
The 2nd relief valve 71a, 71b which opens a, 73b is installed, respectively.

The second relief valve 71a installed in the conduit 73a of the extension side pressure oil path 72a is set to a pressure slightly lower than the operating pressure of the second relief valve 71b installed in the pressure side conduit 73b. .

Therefore, in this embodiment, when the lock pin 28 is retracted into the engagement hole 30 in the overhanging operation of the inner cylinder 22 in which the first offset position 55 of the switching valve 53 is connected to the hydraulic circuit 54, the inner cylinder 22 is Does not expand, the hydraulic pressure in the pressure oil passage 72a increases, which causes the second relief valve 71a to move to the conduit 73a.
Open and return the pressure oil to the oil tank 58 to
The drive of 52 stops.

Further, the second offset position 56 of the switching valve 53 is the hydraulic circuit.
In the retracting operation of the inner cylinder 22 connected to 54, the lock pin 28 sinks into the engagement hole 30 and the hydraulic pressure in the pressure oil passage 72b increases, so that the second relief valve 71b operates and the pipe passage 73b
Is opened and the drive of the hydraulic cylinder 52 is stopped.

The pressure oil in this embodiment corresponds to the medium in this invention, and the relief valve 57b is a safety valve and is set to a higher working pressure than those of the second relief valves 71a and 71b.

In this way, the second hydraulic fluid path 72a, 72b to the hydraulic cylinder 52 opens the pipeline 73a, 73b to the oil tank 58 with the required hydraulic pressure.
Since only the relief valves 71a and 71b need to be provided, the structure is simple and the same function can be obtained by omitting the installation of the second switch 39 as described above. There is an advantage that it is not necessary to add extra parts at positions near 28.

In the case where a hydraulic actuator is used as the expansion / contraction drive means and the pressure oil passage is switched by the switching valve 53 as in the modification of the second embodiment or the first embodiment, the switching valve 53 is a double solenoid operated type. It is a switching valve and energizes each solenoid by the first switch 37 in the first embodiment.
Alternatively, each contact 37b or 37c may be controlled.

 Next, a third embodiment will be described with reference to FIG.

In this embodiment, a breaker 81 is installed in place of the second switch 39 installed in the first embodiment, and other points are the same as in the first embodiment, so only the differences will be described here. Do.

That is, the power supply circuit 41 of this embodiment includes a power supply 42, a rotation direction control unit 43, and a breaker 81. The rotation direction control unit 43 is connected to the power supply 42, and the rotation direction control unit 43. A breaker 81 is disposed between the electric motor 35 and the electric motor 35.

This breaker 81 opens the circuit when a current that exceeds a preset current value flows, and the current value at which this breaker 81 operates is the current value that accompanies the normal overhang or storage drive of the inner cylinder 22. It has a slightly larger current value.

This is to detect the engagement / disengagement of the lock pin 28 by utilizing the property that the power supply current supplied to the electric motor 35, which is the expansion / contraction drive means, changes according to the size of the load, and This is for opening and stopping the drive.

When the breaker 81 for such a power supply circuit 41 is installed, a current according to the load applied to the electric motor 35 always flows through the breaker 81, and when the lock pin 28 is immersed in the engagement hole 30 of the inner cylinder 22, Since a large load is applied to the electric motor 35, a large current flows through the breaker 81, whereby the breaker 81 opens the power supply circuit 41 and the driving of the electric motor 35 is stopped.

The medium in this embodiment is the power supply current of the electric motor 35.

In this embodiment, a breaker 81 that opens the circuit at a predetermined current is installed in the power supply circuit to the electric motor 35 to perform the same function as described above, and the structure is extremely simple, and in the vicinity of the lock pin 28. There is an advantage that it is not necessary to additionally install special parts such as the second switch 39.

Although the breaker 81 is arranged at a position different from that of the second switch 39 of the first embodiment in this embodiment, the breaker 81 may be installed at the same position.

(Effect of the Invention) As described above, according to the present invention, the outer cylinder is provided with the lock pin that is elastically urged toward the inner cylinder and that can be moved back and forth, and the inner end of the lock pin faces. In an expansion / contraction control device for an outrigger device of this type having an engagement hole formed in an inner cylinder, a medium whose physical quantity changes with the engaging operation of the lock pin to the engagement hole is provided, and the physical quantity of the medium changes. Since the operation of the telescopic drive means is stopped by the above, the inner cylinder that has reached a predetermined position by the telescopic drive means is automatically locked to the outer cylinder by the lock pin,
With the locking operation of the lock pin, the expansion / contraction drive means is automatically stopped by the medium.

Further, there are few components to be added in constructing this expansion and contraction control device, and it is possible to construct relatively easily.
Therefore, the addition of a member to be arranged near the lock pin of this expansion and contraction control device is extremely small, and there is an advantage that the structure in this part is not so complicated.

[Brief description of drawings]

1 to 5 relate to the first embodiment of the present invention, FIG. 1 is an explanatory view of the overall configuration of the outrigger device, FIG. 2 is a top view of the expansion and contraction control device, and FIG. 3 is III of FIG. -III cross section,
FIG. 4 is a schematic diagram of a power supply circuit, FIG. 5 is a detailed diagram of the power supply circuit, FIG. 6 is a hydraulic circuit diagram of a modification of the first embodiment, and FIG. 7 is a hydraulic circuit diagram of the second embodiment. FIG. 8 is a power supply circuit diagram of the third embodiment, FIGS. 9 and 10 are related to a conventional example, FIG. 9 is a perspective view of an outrigger device, and FIG. 10 is a cross-sectional view of a telescopic control device. 20; Outrigger device, 21; Outer cylinder, 22; Inner cylinder, 26; Expansion / contraction control device, 28; Lock pin, 30; Engagement hole, 31; Operating lever, 33; Hydraulic pump, 35, Electric motor, 39; Switch (Second switch), 41; power supply circuit, 52; hydraulic actuator (hydraulic cylinder), 57, 72a, 72b; pressure oil passage, 57b; relief valve, 58; drain device (oil tank), 71a, 71b; 2 relief valve,
73a, 73b; oil passage (pipe), 81; breaker.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location E02F 9/08 E02F 9/08 A

Claims (4)

(57) [Scope of utility model registration request] 1. An outer cylinder horizontally mounted on a vehicle body frame, an inner cylinder which is elastically fitted into the outer cylinder and has a jack vertically provided at its tip, and an extension / contraction drive for extending / contracting the inner cylinder with respect to the outer cylinder. And a lock pin that is elastically urged toward the inner cylinder and is capable of advancing and retreating, and the inner cylinder facing the inner end of the lock pin is appropriately disposed. A plurality of engaging holes are formed at intervals, and the lock pin is advanced and retracted so that the inner end portion is engaged with and disengaged from the engaging hole formed in the inner cylinder to fix and release the inner cylinder to the outer cylinder. In the expansion / contraction control device for the outrigger device, a medium whose physical quantity changes in accordance with the engagement operation of the lock pin with the engagement hole is provided, and the operation of the expansion / contraction drive means is stopped by the change in the physical quantity of the medium. Characteristic outrigger expansion control device Place. 2. The expansion / contraction control device for an outrigger device according to claim 1, wherein an operating lever extending in a radial direction is pivotally supported on an upper portion of the lock pin, and the operating lever is rocked to move the lock pin forward and backward. A switch for stopping the operation of the expansion and contraction drive means is arranged in the vicinity of the operation lever, and the switch is operated by the displacement of the operation lever corresponding to the engagement of the lock pin with the engagement hole. An expansion / contraction control device for an outrigger device, which is characterized by being stopped. 3. The expansion / contraction control device for an outrigger device according to claim 1, wherein the expansion / contraction drive means is constituted by a hydraulic actuator, and a drain device is provided in a pressure oil passage extending from the hydraulic pump to the hydraulic actuator at a hydraulic pressure higher than a normal operating hydraulic pressure. An expansion / contraction control device for an outrigger device, which is provided with a relief valve for opening an oil passage leading to. 4. An expansion / contraction control device for an outrigger device according to claim 1, wherein said expansion / contraction driving means is constituted by an electric motor, and a power supply circuit of this electric motor is opened by a current larger than a normal power supply current. An expansion / contraction control device for an outrigger device, wherein the expansion / contraction control device is interposed.