JP4912666B2 - Jack device for work vehicle - Google Patents

Description

  The present invention makes it possible to brake the rear wheels of the vehicle body by a parking brake, and arranges a pair of left and right front jacks that support the vehicle body near the front wheels, and arranges a pair of left and right rear jacks that support the vehicle body near the rear wheels, The present invention relates to a jack device for a work vehicle configured such that the vehicle body can be horizontally supported by the front and rear jacks.

  As this type of work vehicle, there is an aerial work vehicle or a mobile crane vehicle in which a telescopic boom that can turn and undulate freely is arranged on the vehicle. A front jack and a rear jack are arranged in the vicinity of the front wheel and the rear wheel of the work vehicle, respectively, and the work vehicle is supported by these jacks, so that the work vehicle is prevented from falling due to a load acting on the telescopic boom. We try to support it stably. That is, the work vehicle operates the telescopic boom after the jacks are grounded to the ground and the work vehicle is stably supported on the ground before starting the work.

  By the way, when grounding each jack on an inclined ground and supporting the work vehicle from the ground, the front jack arranged near the front wheels (wheels not braked by the parking brake) is first grounded and the grounding reaction force is generated by the front jack. After receiving the rear jack, the rear jack is placed near the rear wheel (the wheel braked by the parking brake), and then the rear jack is extended (extended) until the rear jack receives a ground reaction force. Thereafter, the amount of extension (extension) of each jack is adjusted so that the work vehicle is horizontal, and the work vehicle is supported on the ground by each jack.

Conversely, when storing each jack from a state where the work vehicle is horizontally supported by each jack on an inclined ground, the rear jacks disposed near the rear wheels (wheels braked by the parking brake) are stored (reduced). Then, the rear jack is retracted (reduced) until the rear jack is in the non-ground reaction force state. Thereafter, the front jack disposed in the vicinity of the front wheel (wheel not braked by the parking brake) is first retracted (reduced), and the front jack is retracted (reduced) until the front jack is in a non-ground reaction force state. Next, all jacks are stored (reduced).
As described above, when each jack is extended (extended) and stored (reduced) on an inclined ground, each jack is subjected to sequence control to prevent the work vehicle from running away. That is, when each jack is extended (extension) and retracted (reduction) on an inclined ground, if the work vehicle is supported by the front wheels (wheels not braked by the parking brake) and the rear jacks, the rear jacks slip. The work vehicle may run away. Therefore, as described above, when each jack is extended (extended), the front jack is first grounded to generate a ground reaction force, and the rear jack is extended (extended) later, and each jack is stored. In the case of (reduction), the rear jack is first retracted (reduced) so that the rear jack is in a non-ground reaction force state (a state where the work vehicle is supported by the rear wheel braked by the parking brake), and then the front and rear jacks Is stored (reduced).

Based on such an idea, it is expensive to arrange a detector for detecting the state of the jack for performing the above sequence control. Therefore, a technique for performing control with time and performing it with a simple configuration at low cost is known. It is. (For example, see Patent Document 1)
Japanese Patent No. 3479450 (pages 1 and 2, FIG. 1, FIG. 2, FIG. 3)

However, in the above-mentioned known technology, the jack sequence is controlled and the jack is extended and stored so that it can be prevented from running away even on sloping ground, but because the expansion stroke of the front jack and the rear jack is the same, It was not adapted to support the work vehicle horizontally on a steep slope. Therefore, the extension stroke of the front jack is made longer than the rear jack so that the work vehicle can be supported horizontally even on a steep slope.
However, in order to store the jack from the state in which the extension stroke of the front jack is lengthened and the work vehicle is horizontally supported (the state of (A) in FIG. 7), the rear jack is first stored (reduced) by the jack sequence. The rear jack is put into a state of non-ground reaction force (a state where the work vehicle is supported by the rear wheel braked by the parking brake). Therefore, when the rear jack is reduced to the state of non-ground reaction force, the rear end lower part of the work vehicle interferes with the ground (the state of (b) in FIG. 7). It could be damaged.

  An object of this invention is to provide the jack apparatus of the working vehicle which solves such a subject.

In order to achieve the above object, according to a first aspect of the present invention, there is provided a jack device for a work vehicle in which a rear wheel of a vehicle body can be braked by a parking brake and a pair of front jacks for supporting the vehicle body in the vicinity of the front wheel In addition, a pair of left and right rear jacks for supporting the vehicle body in the vicinity of the rear wheels are arranged, the extension stroke of the front jack is extended with respect to the rear jack, and the vehicle body is configured so that the vehicle body can be horizontally supported even on sloping ground by the front and rear jacks The jack device of
A jack storage operation means, a front jack reduction detection means for detecting that the front jack has been reduced to a predetermined position, a rear jack non-grounding state detection means for detecting a state in which the ground reaction force does not act on the rear jack, Jack operating means for operating each jack, and jack storing control means for receiving signals from the jack storing operation means, front jack reduction detecting means and rear jack non-grounding state detecting means and outputting control signals to the jack operating means. The jack storage control means receives the storage operation signal from the jack storage operation means, reduces the front jack until the detection signal from the front jack reduction detection means is input, and then detects the rear jack non-ground state. The rear jack is reduced until a detection signal is input from the means, and then the front jack is reduced and the front jack is reduced. Is characterized in that it has adapted to reduce the rear jack causes to elapse ungrounded state and outputs a signal to each jack actuating means so as to store each jack with.

  According to a second aspect of the present invention, there is provided the work vehicle jack device according to the first aspect, wherein the front jack reduction detection means directly detects that the front jack is attached to the front jack and is reduced to a predetermined position, and stores the jack. It is characterized by comprising a pre-jack reduction detector that outputs a detection signal to the control means.

  According to a third aspect of the present invention, there is provided a jack device for a work vehicle according to the first aspect, wherein the front jack contraction detecting means includes a front jack expansion / contraction length detector that detects an expansion / contraction length of the front jack, and a front jack. Pre-jack expansion / contraction length storage means for storing the front jack expansion / contraction length when contracted to a predetermined position, front jack expansion / contraction length detection means, and front jack receiving a signal from the predetermined expansion / contraction length storage means. It is characterized by comprising a pre-jack reduction determination means for outputting a determination signal to the jack storage control means when it is determined and determined that the position has been reduced to the position.

  According to a fourth aspect of the present invention, there is provided the work vehicle jack device according to the first aspect, wherein the front jack reduction detection means includes a front jack reduction time storage means for storing a time for the front jack to reduce to a predetermined position, and a jack. Consists of a timer that outputs the time-up signal to the jack storage control means when the time measured after receiving the operation start signal of the storage operation switch reaches the time stored in the previous jack reduction time storage means It is characterized by that.

  According to a fifth aspect of the present invention, there is provided the work vehicle jack device according to the first aspect, wherein the front jack reduction detection means includes a tilt angle detector that detects a tilt angle in a longitudinal direction of the vehicle body, and the front jack to a predetermined position. When the tilt angle storage means for storing the tilt angle when reduced and the signals from the tilt angle detector and the tilt angle storage means receive and determine that the tilt angle of the vehicle body has reached the tilt angle required for storage, It is characterized by comprising a pre-jack reduction determination means for outputting a determination signal to the jack storage control means.

  According to a sixth aspect of the present invention, there is provided a work vehicle jack device according to the fifth aspect, further comprising: a tilt angle setting unit that is operated to store a tilt angle of a vehicle body before the jack is grounded, The means receives the signals from the inclination angle detector and the inclination angle setting means and stores the inclination angle of the vehicle body before grounding the jack as the inclination angle when the front jack is reduced to a predetermined position. It is what.

  The jack device for a work vehicle according to the first aspect of the present invention can support the work vehicle even on a steep slope by configuring the front jack with a long jack. Further, when the jack storage control means receives the storage operation signal from the jack storage operation means, the jack storage control means reduces the front jack until a detection signal is input from the front jack reduction detection means to detect that the front jack has been reduced to a predetermined position. After that, the rear jacks are reduced until a detection signal is input from the rear jack non-grounding state detecting means, and then the front jacks are reduced to allow the front jacks to pass through the non-grounding state, and the rear jacks are reduced to reduce the respective jacks. A signal is output to each jack actuating means so as to be stored.

  Therefore, since the rear jack is reduced and the non-grounding state of the rear jack is detected and then the front jack is stored in a non-grounded state, the brake is braked by the parking brake when the jack is stored. After being supported by the wheel, the jack can be stored so as to be supported by the front wheel, and the work vehicle can be prevented from running away. Moreover, since the front jack having a long expansion / contraction stroke is reduced to a predetermined position before the rear jack is reduced, the lower part of the rear end of the work vehicle interferes with the ground even if the rear jack is reduced. The inclination angle can be prevented.

  A jack device for a work vehicle according to a second aspect of the present invention is the jack storage control according to the first aspect, wherein the front jack reduction detecting means directly detects that the front jack is reduced to a predetermined position and is attached to the front jack. Because it consists of a front jack reduction detector that outputs a detection signal to the means, it can be directly detected by the front jack reduction detector that the front jack has been reduced to a predetermined position, and the predetermined position can be accurately detected without error. Can do. Therefore, before the rear jack is reduced, the front jack having a long expansion / contraction stroke is reduced to a predetermined position. Therefore, even if the rear jack is reduced, the lower part of the rear end of the work vehicle interferes with the ground. Each jack can be stored so as not to have an inclination angle.

  According to a third aspect of the present invention, there is provided a work vehicle jack device according to the first aspect, wherein the front jack contraction detection means is a front jack expansion / contraction length detection means for detecting a front jack extension / contraction length, and a front jack is predetermined. Pre-jack expansion / contraction length storage means for storing the front jack expansion / contraction length when contracted to the position, front jack expansion / contraction length detection means, and a signal from the front jack expansion / contraction length storage means for receiving the signals from the front jack. It is composed of a front jack reduction judgment means that outputs a judgment signal to the jack storage control means when it is judged and judged that it has been shrunk to the front jack, so that the extension length of the front jack is detected on the front jack. A predetermined position can be easily detected indirectly simply by attaching a means. Therefore, before the rear jack is reduced, the front jack having a long expansion / contraction stroke is reduced to a predetermined position. Therefore, even if the rear jack is reduced, the lower part of the rear end of the work vehicle interferes with the ground. Each jack can be stored so as not to have an inclination angle. Moreover, since the front jack expansion / contraction length when the front jack is reduced to a predetermined position can be adjusted and stored in the front jack predetermined expansion / contraction length storage means, the predetermined position for reducing the front jack is determined according to the work vehicle. Can be changed easily.

  According to a fourth aspect of the present invention, there is provided a jack device for a work vehicle according to the first aspect, wherein the front jack reduction detection means includes a front jack reduction time storage means for storing a time during which the front jack is reduced to a predetermined position, and a jack storage. A timer that outputs a time-up signal to the jack storage control means when the time measured after receiving the operation start signal of the operation switch reaches the time stored in the previous jack reduction time storage means Therefore, it is possible to easily detect a predetermined position according to time without specially arranging a detector. Therefore, before the rear jack is reduced, the front jack having a long expansion / contraction stroke is reduced to a predetermined position. Therefore, even if the rear jack is reduced, the lower part of the rear end of the work vehicle interferes with the ground. Each jack can be stored so as not to have an inclination angle. Moreover, since the time for reducing the front jack to a predetermined position can be adjusted and stored in the front jack reduction time storage means as appropriate, the predetermined position for reducing the front jack can be easily changed according to the work vehicle.

  According to a fifth aspect of the present invention, there is provided a work vehicle jack device according to the first aspect, wherein the front jack reduction detecting means includes a tilt angle detector for detecting a tilt angle in a longitudinal direction of the vehicle body, and a front jack reduced to a predetermined position. The inclination angle storage means for storing the inclination angle when the vehicle is operated, and the jack when the inclination angle of the vehicle body has reached the inclination angle to be memorized in response to the signals from the inclination angle detector and the inclination angle storage means Since it is composed of a front jack reduction determination means that outputs a determination signal to the storage control means, the front inclination angle detector in the front-rear direction of the work vehicle can be used without a detector for detecting the reduction of the front jack. It is possible to detect when the jack is reduced to a predetermined position. Therefore, before the rear jack is reduced, the front jack having a long expansion / contraction stroke is reduced to a predetermined position. Therefore, even if the rear jack is reduced, the lower part of the rear end of the work vehicle interferes with the ground. The inclination angle can be prevented. In addition, since the inclination angle when the front jack is reduced to a predetermined position can be appropriately adjusted and stored in the inclination angle storage means, the predetermined position for reducing the front jack can be easily changed according to the work vehicle.

  According to a sixth aspect of the present invention, there is provided the work vehicle jack device according to the fifth aspect, wherein the tilt angle setting means operated to store the tilt angle of the vehicle body before grounding the jack is disposed, and the tilt angle storing means is arranged. The inclination angle setting means is operated before the jack is grounded, and the inclination angle of the vehicle body detected by the inclination angle detector when operated is stored as the inclination angle when the front jack is reduced to a predetermined position. Therefore, even if a detector for detecting the reduction of the front jack is not arranged, the front jack can be reduced until the inclination angle in the front-rear direction of the work vehicle becomes the inclination angle of the vehicle body before grounding the jack. it can.

  Therefore, before the rear jack is shrunk, it is shrunk until it reaches the inclination angle of the vehicle body before the front jack is grounded with a long extension stroke. Each jack can be stored in such a way that the inclination angle of the work vehicle does not interfere with the angle. Moreover, since the vehicle body inclination angle storage means stores the vehicle body inclination angle before the front jack is grounded, it is not necessary to store a predetermined position for reducing the front jack in advance. Each jack can be stored after the tilt angle.

  Embodiments of a work vehicle jack device according to the present invention will be described below with reference to FIGS. As an example of the work vehicle, an aerial work vehicle shown in FIG. 6 will be described below. The aerial work vehicle has a telescopic boom 2 that can turn and undulate on a vehicle body 1. The aerial work vehicle enables the rear wheel 3 of the vehicle body 1 to be braked by a parking brake, and a pair of left and right front jacks 5 for supporting the vehicle body 1 are arranged in the vicinity of the front wheel 4 and the vehicle body 1 is supported in the vicinity of the rear wheel 3. A pair of left and right rear jacks 6 are arranged, and the extension stroke of the front jack 5 is increased with respect to the rear jack 6 so that the vehicle body 1 can be horizontally supported by the front and rear jacks 5 and 6 even on an inclined ground.

  By grounding each of these jacks 5 and 6, the aerial work vehicle is stably supported so that the aerial work vehicle does not fall down due to a load acting on the telescopic boom 2. That is, the aerial work vehicle operates the telescopic boom 2 after the jacks 5 and 6 are grounded to the ground and stably support the aerial work vehicle on the ground before starting the work. The work table 7 attached to the work table 7 is moved, and the operator who has boarded the work table 7 is moved to an appropriate height position to perform work at a high place.

  As shown in FIG. 6 (a), an aerial work vehicle having a long extension stroke of the front jack 5 can be grounded by extending the extension stroke of the front jack 5 even in a steep slope. The vehicle body 1 can be supported horizontally with respect to the ground.

In the first embodiment and such an aerial work vehicle, a jack device A as shown in FIG. 1 is arranged to store the jack from a horizontally supported state. Hereinafter, a jack apparatus A illustrated in FIG. 1 will be described as a first embodiment. Reference numeral 10 denotes front jack reduction detection means for detecting that the front jack 5 has been reduced to a predetermined position. This front jack reduction detection means 10 is directly attached to the front jack 5, and is a detector constituted by a switch that operates when the front jack 5 is reduced from the state shown in FIG. 6 (a) to the state shown in FIG. 6 (b). It is. This switch is arranged as a right front jack reduction detector 10a on the right front jack 5, and is arranged as a left front jack reduction detector 10b on the left front jack 5, respectively. Here, the state shown in FIG. 6B detected by the front jack reduction detection means 10 is specifically defined as a position where the front jack 5 is reduced until it becomes equal to the height of the rear jack 6.

  Moreover, although the said predetermined position was made into the position which reduced the front jack 5 until it became equal to the height amount of the rear jack 6, you may determine as follows. That is, when the rear jack 6 is reduced to a non-grounding state where the grounding reaction force does not act on the rear jack 6 as in the state of FIG. In order to prevent the rear lower end of the work vehicle from interfering with the ground, the front jack 5 is reduced in advance by a predetermined amount. What is necessary is just to determine as the reduction | decrease amount of the front jack 5 required so that the rear-end lower part of the vehicle body 1 may not interfere with the ground when storing.

  Reference numeral 11 denotes a jack storage operation means that is operated when the jack storage operation is started when the front and rear jacks 5 and 6 are stored in the jack apparatus A, and is configured by a switch, and outputs the operated operation signal. I am doing so. 12 is a rear jack non-grounding detecting means for detecting when the rear jack 6 is contracted and the grounding reaction force no longer acts on the rear jack 6 and becomes non-grounded, and outputs a detection signal. 6 includes a right rear jack non-grounding detector 12a for detecting the ungrounded state 6 and a left rear jack non-grounding detector 12b for detecting the non-grounded state of the left rear jack 6.

  Specifically, the right rear jack non-grounding detector 12a and the left rear jack non-grounding detector 12b are attached to the right rear jack 6 and the left rear jack 6, respectively, and directly detect and detect. It consists of switches that output signals.

  Reference numeral 14 denotes a right front jack operating means, which is an operating means for controlling expansion and contraction of the right front jack 5. Reference numeral 15 denotes a left front jack operating means, which is an operating means for controlling expansion / contraction of the left front jack 5. Reference numeral 16 denotes a right rear jack operating means, which is an operating means for controlling expansion and contraction of the right rear jack 6. Reference numeral 17 denotes a left rear jack operating means that controls the expansion and contraction of the left rear jack 6.

  Reference numeral 13 denotes the jack storing operation means 11, the front jack reduction detection means 10 (both detection signals from the right front jack reduction detector 10a and the left front jack reduction detector 10b are input), and the rear jack non-grounding state detection means 12. (The detection signals from the right rear jack non-grounding detector 12a and the left rear jack non-grounding detector 12b are input), and control signals are sent to the jack operating means 14, 15, 16, and 17, respectively. Jack storage control means (controller) for outputting. When the jack storage control means 13 receives the storage operation signal from the jack storage operation means 11, the jack storage control means 13 reduces the front jack 5 until the detection signal from the front jack reduction detection means 10 is input, and then the rear jack is not grounded. The rear jacks 6 are reduced until a detection signal is input from the state detection means 12, and then the front jacks 5 and 6 are reduced to allow the front jacks 5 to pass through the non-grounding state, and the rear jacks 6 are reduced to reduce the respective jacks 5. , 6 are stored, control signals are output to the jack operating means 14, 15, 16, 17 respectively.

The jack device A for a work vehicle according to the present invention configured as described above operates as follows.
Assume that the aerial work vehicle is horizontally grounded on a steep slope as shown in FIG. In order to store the front and rear jacks 5 and 6 from this state, the jack storing operation means 11 of the jack apparatus A is operated to start the storing operation. Then, the jack storage control means 13 receives the storage operation signal from the jack storage operation means 11 and receives the detection signal from the front jack reduction detection means 10 (the right front jack reduction detector 10a and the left front jack reduction detector). Control signals are output to the right front jack operating means 14 and the left front jack operating means 15 until both detection signals from 10b are input), and the right front jack 5 and the left front jack 5 are reduced.

  When the right front jack 5 and the left front jack 5 are contracted to reach the position shown in FIG. 6B, a detection signal from the front jack reduction detection means 10 is input to the jack storage control means 13 (right front jack reduction detector). 10a and both detection signals from the left front jack reduction detector 10b are input). Then, the jack storage control means 13 stops outputting control signals to the right front jack operating means 14 and the left front jack operating means 15 and stops the reduction of the right front jack 5 and the left front jack 5.

  Next, the jack storage control means 13 receives a detection signal from the rear jack non-grounding state detection means 12 (both detection signals from the right rear jack non-grounding detector 12a and the left rear jack non-grounding detector 12b are input). Control signals are output to the right rear jack actuation means 16 and the left rear jack actuation means 17 until the rear jack 6 (the right rear jack 6 and the left rear jack 6) is reduced.

  When the rear jack 6 (the right rear jack 6 and the left rear jack 6) is reduced to the position shown in FIG. 6C, the grounding reaction force no longer acts on the rear jack 6 (non-grounding state). The rear part of the aerial work vehicle is supported by a rear wheel 3 braked by a parking brake. Then, the jack storing control means 13 outputs a control signal for reducing the right front jack operating means 14 and the left front jack operating means 15 to reduce the front jack 5 so that the non-grounding state of the front jack 5 elapses and the rear jack 6 Is output to the jack operating means 14, 15, 16, 17 so that the jacks 5, 6 are stored. Then, the jacks 5 and 6 are reduced until the storage state shown in FIG.

  As described above, the jack device for a work vehicle according to the present invention can support the work vehicle even on a steep slope by configuring the front jack 5 with a long jack. Moreover, when the jack storage control means 13 receives the storage operation signal from the jack storage operation means 11, until the detection signal for detecting that the front jack 5 is reduced to the predetermined position is input from the front jack reduction detection means 10. After the front jack 5 is reduced, the rear jack 6 is reduced until a detection signal is input from the rear jack non-grounding state detecting means 12, and then the front jack 5 is reduced to pass the non-grounding state of the front jack. A signal is output to each jack operating means 14, 15, 16, and 17 so that the rear jack 6 is reduced and the jacks 5 and 6 are stored.

  Therefore, since the rear jack 6 is reduced and the rear jack 6 is detected to be in a non-grounded state, the front jack 5 is stored in a non-grounded state. After being supported by the rear wheel 3, the jack is retracted so as to be supported by the front wheel 4, thereby preventing the work vehicle from running away. In addition, since the front jack 5 having a long expansion / contraction stroke is reduced to a predetermined position before the rear jack 6 is reduced, the rear end lower portion of the work vehicle interferes with the ground even if the rear jack 6 is reduced. The inclination angle of the work vehicle can be prevented.

Second Embodiment Next, in the first embodiment, the front jack reduction detecting means 10 is directly attached to the front jack 5, and the front jack 5 is moved from the state shown in FIG. 6 (a) to the state shown in FIG. 6 (b). The right front jack reduction detector 10a and the left front jack reduction detector 10b are arranged respectively. However, the front jack reduction detection means 20 shown in FIG. You may make it comprise. Accordingly, the jack device B of the second embodiment shown and described in FIG. 2 is the same as that of the first embodiment except for the front jack reduction detection means 20, and therefore the parts other than the front jack reduction detection means 20 are the same. Description is omitted.

  The front jack reduction detection means 20 includes a front jack expansion / contraction length detection means 21, a front jack predetermined expansion / contraction length storage means 22, and a front jack reduction determination means 23. The front jack expansion / contraction length detecting means 21 includes a right front jack expansion / contraction length detector 21a for detecting the expansion / contraction length of the right front jack and a left front jack expansion / contraction length detector 21b for detecting the expansion / contraction length of the left front jack. The expansion / contraction length detectors 21a and 21b of the front jacks 5 detect the expansion / contraction lengths of the front jacks 5 using a potentiometer or the like that detects the amount of the cord that is fed and unwound by the cord winder. It is made to detect with things.

  The front jack predetermined expansion / contraction length storage means 22 stores the front jack expansion / contraction length when the front jack 5 is reduced to a predetermined position in advance. The stored extension length of the front jack is the extension length of the front jack so that the lower end of the rear end of the work vehicle does not become an inclination angle of the work vehicle that interferes with the ground. 5 is determined to be the length of expansion / contraction of the front jack when the number 5 is reduced to a predetermined position. The front jack predetermined expansion / contraction length storage means 22 includes a right front jack predetermined expansion / contraction length storage means 22a and a left front jack predetermined expansion / contraction length storage means 22b in each of the right front jack 5 and the left front jack 5. These right front jack predetermined expansion / contraction length storage means 22a and left front jack predetermined expansion / contraction length storage means 22b may store the same front jack predetermined expansion / contraction length, so that the left and right front jack predetermined expansion / contraction length storage means can be stored. Alternatively, a common front jack predetermined expansion / contraction length storage means may be used.

  The front jack reduction determination means 23 receives signals from the front jack expansion / contraction length detection means 21 and the front jack predetermined expansion / contraction length storage means 22 and determines that the front jack 5 has been reduced to a predetermined position. When the determination is made, a determination signal is output to the jack storage control means 13. That is, the front jack reduction determination means 23 includes a right front jack reduction determination means 23 a of the right front jack 5 and a left front jack reduction determination means 23 b of the left front jack 5. The right front jack reduction discriminating means 23a of the right front jack 5 receives the signals from the right front jack expansion / contraction length detector 21a and the right front jack predetermined expansion / contraction length storage means 22a, and the right front jack 5 is reduced to a predetermined position. When this is determined, a determination signal is output to the jack storage control means 13. Similarly, the left front jack reduction determination means 23b of the left front jack 5 receives the signals from the left front jack expansion / contraction length detector 21b and the left front jack predetermined expansion / contraction length storage means 22b, and the left front jack 5 is reduced to a predetermined position. When the determination is made, a determination signal is output to the jack storage control means 13.

  Thus, the jack apparatus B of 2nd Embodiment acts similarly to 1st Embodiment. That is, when the storage operation signal is received from the jack storage operation unit 11, the jack storage control unit 13 moves the front jack 5 from the right front jack reduction determination unit 23a and the left front jack reduction determination unit 23b of the front jack reduction detection unit 20 to a predetermined position. The right front jack 5 and the left front jack 5 are reduced until a determination signal for determining that the reduction has been made is input. Since the subsequent steps are the same as those in the first embodiment, description thereof is omitted.

  In the second embodiment, as in the first embodiment, the rear jack 6 is reduced and the non-grounding state of the rear jack 6 is detected, and then the front jack 5 is stored in a non-grounded state. Therefore, when the jack is stored, the jack is stored by being supported by the front wheel 4 after being supported by the rear wheel 3 braked by the parking brake, and the escape of the work vehicle can be prevented. In addition, since the front jack 5 having a long expansion / contraction stroke is reduced to a predetermined position before the rear jack 6 is reduced, the rear end lower portion of the work vehicle interferes with the ground even if the rear jack 6 is reduced. The inclination angle of the work vehicle can be prevented.

Moreover, in the second embodiment, the predetermined position can be easily detected indirectly simply by attaching the front jack expansion / contraction length detecting means 21 to the front jack 5. Therefore, before the rear jack 6 is reduced, the front jack 5 having a long expansion / contraction stroke can be reduced to a predetermined position, and even if the rear jack 6 is reduced, the rear end lower portion of the aerial work vehicle interferes with the ground. The jacks 5 and 6 can be stored so as not to be inclined. And since the front jack expansion / contraction length when the front jack 5 is reduced to a predetermined position can be appropriately adjusted and stored in the right front jack predetermined expansion / contraction length storage means 22a and the left front jack predetermined expansion / contraction length storage means 22b. It can be easily changed according to the work vehicle to which a predetermined position for reducing the front jack 5 is applied.
In the second embodiment, the front jack expansion / contraction length detection means 21, the front jack predetermined expansion / contraction length storage means 22, and the front jack reduction detection means 20 constituted by the front jack reduction determination means 23, the jack Although the storage control means 13 is individually arranged, the functions of the front jack predetermined expansion / contraction length storage means 22, the front jack reduction determination means 23, and the jack storage control means 13 may be performed by one controller 24. .

Third Embodiment Next, the front jack reduction detection means 10 of the first embodiment may be constituted by a front jack reduction detection means 30 shown in FIG. 3 and described next. Accordingly, the jack device C of the third embodiment shown and described in FIG. 3 is the same as that of the first embodiment except for the front jack reduction detection means 30. Description is omitted.

  The front jack reduction detection means 30 measures and measures the time after receiving the operation start signal of the front jack reduction time storage means 31 storing the time when the front jack 5 is reduced to a predetermined position and the jack storage operation switch 11. The timer 32 is configured to output a time-up signal to the jack storage control means 13 when the time reaches the time stored in the previous jack reduction time storage means 31. The time stored in the front jack reduction time storage means 31 is such that even if the rear jack 6 is reduced, the front jack 5 is held at a predetermined position so that the rear end lower portion of the work vehicle does not have an inclination angle of the work vehicle that interferes with the ground. The time to reduce to is decided.

  Thus, in the jack device C of the third embodiment, when the jack storage control means 13 receives the storage operation signal from the jack storage operation means 11, the jack 32 of the front jack reduction detection means 30 is the same as in the first embodiment. The right front jack actuating means 14 and the left front jack actuating means are measured until a time-up signal has been measured from the start of operation of the jack storage operation switch 11 until the time when the measured time reaches the time stored in the previous jack reduction time storage means 31 is received. The control signal is output to 15 and the right front jack 5 and the left front jack 5 are reduced. When the measured time reaches the time stored in the previous jack reduction time storage means 31, the jack storage control means 13 receives a time-up signal from the timer 32 and activates a right front jack operation as a control signal for reducing the front jack 5. The output to the means 14 and the left front jack actuating means 15 is stopped, and the reduction of the right front jack 5 and the left front jack 5 is stopped. Since the subsequent steps are the same as those in the first embodiment, description thereof is omitted.

  In the third embodiment, as in the first embodiment, the rear jack 6 is reduced and the non-grounding state of the rear jack 6 is detected, and then the front jack 5 is stored in a non-grounded state. Therefore, when the jack is retracted, the jack is retracted by supporting it with the rear wheel 3 braked by the parking brake and then supporting it with the front wheel 4, thereby preventing the work vehicle at high altitude from running away. Moreover, since the front jack 5 having a long expansion / contraction stroke is reduced to a predetermined position before the rear jack 6 is reduced, the rear end lower portion of the aerial work vehicle interferes with the ground even if the rear jack 6 is reduced. Such an inclination angle can be prevented.

  In addition, in the third embodiment, the time for reducing the front jack 5 to a predetermined position can be adjusted and stored in the front jack reduction time storage means 31 without any special detector, and the front jack 5 can be stored. It can be easily changed according to the work vehicle to which the predetermined position to be reduced is applied.

  In the third embodiment, the front jack reduction detection means 30 and the jack storage control means 13 are individually arranged. However, both functions may be performed by one controller 33.

Fourth Embodiment Next, the front jack reduction detection means 10 of the first embodiment may be constituted by a front jack reduction detection means 40 shown in FIG. 4 and described next. Accordingly, the jack device D of the fourth embodiment shown and described in FIG. 4 is the same as that of the first embodiment except for the front jack reduction detection means 40. Description is omitted.

  The front jack reduction detection means 40 includes an inclination angle detector 41 that detects an inclination angle in the longitudinal direction of the vehicle body, an inclination angle storage means 42 that stores an inclination angle when the front jack 5 is reduced to a predetermined position, and an inclination angle detection. The jack reduction determination means outputs a determination signal to the jack storage control means 13 when it is determined and determined that the inclination angle of the vehicle body has reached the inclination angle required for storage by receiving signals from the device 41 and the inclination angle storage means 42. 43. The inclination angle stored in the inclination angle storage means 42 is such that even if the rear jack 6 is reduced, the front jack 5 is moved to a predetermined position so that the rear end lower part of the work vehicle does not interfere with the ground. The inclination angle to be reduced is determined.

  As described above, in the jack device D of the fourth embodiment, when the jack storage control means 13 receives the storage operation signal from the jack storage operation means 11, the jack storage control means 13 receives the vehicle body from the front jack reduction determination means 43 as in the first embodiment. A control signal for reducing the right front jack 5 and the left front jack 5 is output to the right front jack operating means 14 and the left front jack operating means 15 until a determination signal that the inclination angle reaches the inclination angle required for storage is output. When the inclination angle of the vehicle body reaches the storage inclination angle, the jack storage control means 13 receives a determination signal from the front jack reduction determination means 43 and sends a control signal for reducing the front jack 5 to the right front jack operation means 14 and the left front jack. The output to the actuating means 15 is stopped, and the reduction of the right front jack 5 and the left front jack 5 is stopped. Since the subsequent steps are the same as those in the first embodiment, description thereof is omitted.

  In the fourth embodiment, as in the first embodiment, the rear jack 6 is reduced and the non-grounding state of the rear jack 6 is detected, and then the front jack 5 is stored in a non-grounded state. Therefore, when the jack is retracted, the jack is retracted by supporting it with the rear wheel 3 braked by the parking brake and then supporting it with the front wheel 4, thereby preventing the work vehicle at high altitude from running away. Moreover, since the front jack 5 having a long expansion / contraction stroke is reduced to a predetermined position before the rear jack 6 is reduced, the rear end lower portion of the aerial work vehicle interferes with the ground even if the rear jack 6 is reduced. Such an inclination angle can be prevented.

  Even when the detector is not disposed on the front jack 5, it is possible to detect when the front jack 5 is reduced to a predetermined position by the inclination angle detector 41 in the front-rear direction of the aerial work vehicle. Moreover, since the inclination angle when the front jack 5 is reduced to a predetermined position can be appropriately adjusted and stored in the vehicle body inclination angle storage means 42, it is easy depending on the work vehicle to which the predetermined position for reducing the front jack 5 is applied. Can be changed.

  In the fourth embodiment, the inclination angle detector 41 for detecting the inclination angle in the longitudinal direction of the vehicle body, the inclination angle storage means 42 for storing the inclination angle when the front jack 5 is reduced to a predetermined position, and the inclination angle detection. The jack reduction determination means outputs a determination signal to the jack storage control means 13 when it is determined and determined that the inclination angle of the vehicle body has reached the inclination angle required for storage by receiving signals from the device 41 and the inclination angle storage means 42. 43, the front jack reduction detection means 40 and the jack storage control means 13 are individually arranged. The vehicle body inclination angle storage means 42, the front jack reduction determination means 43, and the jack storage control means 13 are combined into one function. The controller 45 may perform this.

Fifth Embodiment Next, in the fourth embodiment, the inclination angle when the front jack 5 is reduced to a predetermined position is stored in the inclination angle storage means 42 in advance, but the vehicle body before the jack is grounded May be stored. That is, the front jack reduction detection means may be constituted by the front jack reduction detection means 50 shown in FIG. 5 and described next. Accordingly, the jack device E of the fifth embodiment shown and described in FIG. 5 is the same as the fourth embodiment except for the front jack reduction detection means 50. The description will be omitted. The front jack reduction detection means 50 includes an inclination angle detector 41 that detects an inclination angle in the longitudinal direction of the vehicle body, a jack extension operation detection means 51 that detects an extension operation of the jack, and an inclination angle detector 41. In response to the signals from the jack extension operation detecting means 51, the inclination angle storage means 52 for storing the inclination angle of the vehicle body before grounding the jack, and the signals from the inclination angle detector 41 and the inclination angle storage means 52 are received. It is constituted by a pre-jack reduction determination means 43 that outputs a determination signal to the jack storage control means 13 when it is determined and determined that the inclination angle of the current has reached the inclination angle required for storage.

  The jack apparatus E according to the fifth embodiment operates as follows. When the jack is extended, the jack extension operation detecting unit 51 outputs an operation signal to the inclination angle storage unit 52. The inclination angle storage means 52 receives the operation signal from the jack extension operation detection means 51, receives the signal from the inclination angle detector 41, and stores the inclination angle of the vehicle body before the jack is grounded. When the jack extension operation is performed, the jack extension operation detecting means 51 detects the operation, and each jack is extended as follows, which is the same as the conventional one. That is, after the front jack 5 is first extended to receive the ground reaction force by the front jack, the rear jack 6 is extended and the rear jack 6 is extended until the rear jack 6 receives the ground reaction force. Thereafter, the amount of extension of each jack 5, 6 is adjusted so that the work vehicle at a high level is horizontal, and is extended so that it is supported on the ground by each jack 5, 6.

  Next, the jack storing operation means 11 is operated to finish the work and store the jacks 5 and 6. Then, the front jack reduction determination means 43 receives signals from the inclination angle detector 41 and the vehicle body inclination angle storage means 52, and sends a determination signal to the jack storage control means 13 when the inclination angle of the vehicle body reaches the inclination angle for storage. Is output. Therefore, until the jack storage control means 13 receives the operation signal from the jack storage operation means 11 and receives the determination signal from the front jack reduction determination means 43, the jack storage control means 13 sends a control signal for reducing the right front jack 5 and the left front jack 5 to the right front jack. Output to the operating means 14 and the left front jack operating means 15.

  When the inclination angle detector 41 detects the inclination angle of the vehicle body to be stored, the front jack reduction determination means 43 outputs a determination signal to the jack storage control means 13. Then, the jack storage control means 13 stops outputting the control signal for reducing the front jack 5 to the right front jack operating means 14 and the left front jack operating means 15 in response to the determination signal from the front jack reduction determining means 43. The reduction of the jack 5 and the left front jack 5 is stopped. Since the subsequent steps are the same as those in the first embodiment, description thereof is omitted.

  In the fifth embodiment, the inclination angle detected from the inclination angle detector 41 when the operation signal is received from the jack extension operation detecting means 51 is used as the inclination angle of the vehicle body before the jack is grounded. The information is stored in the corner storage means 52. That is, the inclination angle of the vehicle body before the jack is automatically grounded is memorized, but the inclination angle setting means 51a that is manually set is arranged, and this inclination angle setting means before the jack is grounded. The tilt angle storage means 52 may store the tilt angle detected from the tilt angle detector 41 by operating 51a as the tilt angle of the vehicle body before the front jack is grounded.

  In the fifth embodiment, as in the first embodiment, the rear jack 6 is reduced and the non-grounding state of the rear jack 6 is detected, and then the front jack 5 is stored in a non-grounded state. Therefore, when the jack is retracted, the jack is retracted by supporting it with the rear wheel 3 braked by the parking brake and then supporting it with the front wheel 4, thereby preventing the work vehicle at high altitude from running away. Moreover, since the front jack 5 having a long expansion / contraction stroke is reduced to a predetermined position before the rear jack 6 is reduced, the rear end lower portion of the aerial work vehicle interferes with the ground even if the rear jack 6 is reduced. Such an inclination angle can be prevented.

  Since the inclination angle storage means 52 stores the inclination angle of the vehicle body before the front jack 5 is grounded, it is not necessary to store a predetermined position for reducing the front jack 5 in advance. The jacks 5 and 6 can be retracted after the inclination angle is parallel to the ground.

  In the fifth embodiment, the inclination angle detector 41 for detecting the inclination angle in the longitudinal direction of the vehicle body, the jack extension operation detecting means 51 for detecting the extension operation of the jack, the inclination angle detector 41 and the jack extension. An inclination angle storage means 52 that receives a signal from the operation detection means 51 and stores the inclination angle of the vehicle body before grounding the jack, and receives signals from the inclination angle detector 41 and the inclination angle storage means 52 to determine the inclination angle of the vehicle body. A front jack reduction detection means 50 comprising a front jack reduction determination means 43 that outputs a determination signal to the jack storage control means 13 when it is determined and determined that the inclination angle for storage has been reached, and the jack storage control means 13 Are arranged individually, but the functions of the inclination angle storage means 52, the front jack reduction determination means 43 and the jack storage control means 13 are performed by one controller 53. It may be.

  In the above embodiment, the right rear jack non-grounding detector 12a and the left rear jack non-grounding detector 12b are attached to the right rear jack 6 and the left rear jack 6, respectively, and are in a non-grounded state with a switch. Although detection is performed, detection when the right rear jack 6 and the left rear jack 6 are in a non-grounded state can be detected by the expansion / contraction length, time, and vehicle body inclination angle as in the case of the front jack reduction detection means. .

Development example of the first embodiment Although the front jack reduction detection means 10 fails and the front jack 5 is reduced to a predetermined position, a detection signal is output from the right front jack reduction detector 10a or the left front jack reduction detector 10b. Is not output, the jack storage control means 13 reduces the right front jack 5 and the left front jack 5 until detection signals are output from both the right front jack reduction detector 10a and the left front jack reduction detector 10b. Is output to the right front jack operating means 14 and the left front jack operating means 15. Therefore, the front jack 5 is reduced to a predetermined position or more. Therefore, it is safer to notify that the front jack reduction detection means 10 has failed and to stop the control of the jack device A as follows.

  Specifically, when the jack is extended by controlling the jack sequence, it is necessary to detect that the front jack 5 is first extended and the grounding reaction force is received by the front jack 5 as in the prior art. A ground detector and a front left jack ground detector are arranged. That is, after detecting that the front jack 5 is grounded by these grounding detectors, the rear jack 6 is extended, and the rear jack 6 is extended until the rear jack 6 receives a ground reaction force. Thereafter, the extension amount of the jacks 5 and 6 is adjusted so that the work vehicle at a high level is horizontal, and the extension control is performed so that the jacks 5 and 6 support the ground.

  Therefore, it is possible to determine that the front jack reduction detection means 10 has failed using the grounding detector of the front jack. That is, the jack storage control means 13 receives the operation signal from the jack storage operation means 11 and outputs the detection signals from the right front jack 5 until the detection signals are output from both the right front jack reduction detector 10a and the left front jack reduction detector 10b. A control signal for reducing the left front jack 5 is output to the right front jack operating means 14 and the left front jack operating means 15 to reduce the right front jack 5 and the left front jack 5.

  At this time, if a non-ground signal is received from the ground detector of the right front jack or the ground detector of the left front jack before detection signals are output from both the right front jack reduction detector 10a and the left front jack reduction detector 10b, A control signal is sent to the right front jack operating means 14 and the left front jack operating means 15 to warn that the right front jack reduction detector 10a or the left front jack reduction detector 10b is out of order and to stop the reduction of the right front jack 5 and the left front jack 5. Is stopped, and the reduction of the right front jack 5 and the left front jack 5 is stopped.

Example of Development in Other Embodiments In the above example of development, the example in the first embodiment is applied. In the second to sixth embodiments as well, each of the front jack reduction detection means uses the front jack ground detector. It can be determined that 20, 30, 40, and 50 are out of order. Even if this is not described in detail, it can be understood that the second to sixth embodiments can be easily made by referring to the development example of the first embodiment, and thus the description thereof will be omitted.

  In each of the above embodiments, an aerial work vehicle has been described as an example of a work vehicle. Of course you can.

It is explanatory drawing explaining 1st Embodiment of the jack apparatus of the working vehicle which concerns on this invention, Comprising: It is explanatory drawing at the time of making it detect with the front jack reduction | decrease detector in order to reduce a front jack to a predetermined position. It is explanatory drawing explaining 2nd Embodiment of the jack apparatus of the working vehicle which concerns on this invention, and is explanatory drawing at the time of making it detect the expansion-contraction length of a front jack in order to reduce a front jack to a predetermined position. It is explanatory drawing explaining 3rd Embodiment of the jack apparatus of the working vehicle which concerns on this invention, Comprising: It is explanatory drawing at the time of making it detect by jack reduction time, in order to reduce a front jack to a predetermined position. It is explanatory drawing explaining 4th Embodiment of the jack apparatus of the working vehicle which concerns on this invention, and is explanatory drawing at the time of making it detect a vehicle body inclination angle to reduce a front jack to a predetermined position. It is explanatory drawing explaining 5th Embodiment of the jack apparatus of the working vehicle which concerns on this invention, The vehicle body inclination angle before grounding a jack is detected in order to reduce a front jack to a predetermined position, and a front jack is reduced to a predetermined position. It is explanatory drawing at the time of making it make it the vehicle body inclination angle before once grounding a jack. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing explaining embodiment of the jack apparatus of the working vehicle which concerns on this invention, (a) has shown the state which earth | grounded the aerial work vehicle by grounding the jack on the steep slope. (B) shows a state where the front jack is reduced to a predetermined position from the state (A). (C) shows a state in which the rear jack is reduced from the state (b) and the rear jack is reduced to a non-grounding state in which the grounding force is not received by the rear jack. (D) shows a storage state in which each jack is reduced from the state (C). It is explanatory drawing explaining embodiment of the jack apparatus of the conventional work vehicle, (a) has shown the state which grounded the jack on the steep slope and leveled the aerial work vehicle. (B) In the state where the rear jack is reduced from the state (a) to the non-grounded state where the rear jack is no longer subjected to the ground reaction force, the lower rear end of the aerial work vehicle interferes with the ground. Shows the state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Car body 3 Rear wheel 4 Front wheel 5 Front jack 6 Rear jack 11 Jack storage operation means 12 Rear jack non-grounding detection means 10 Front jack reduction detection means 10a Right front jack reduction detector 10b Left front jack reduction detector 13 Jack storage control means 14 Right front Jack operating means 15 Left front jack operating means 16 Right rear jack operating means 17 Left rear jack operating means 20 Front jack reduction detection means 21 Front jack expansion / contraction length detection means 22 Front jack predetermined expansion / contraction length storage means 23 Front jack reduction determination means 30 Front jack reduction detection means 31 Front jack reduction time storage means 32 Timer 40 Front jack reduction detection means 41 Inclination angle detector 42 Inclination angle storage means 43 Front jack reduction determination means 50 Front jack reduction detection means 51 Jack extension operation detection means ( Inclination angle setting means)
52 Inclination angle storage means 51a Inclination angle setting means A Jack device B Jack device C Jack device D Jack device E Jack device

Claims (6)

The rear wheels of the vehicle body can be braked by a parking brake, a pair of left and right front jacks that support the vehicle body are arranged near the front wheels, and a pair of left and right rear jacks that support the vehicle body are arranged near the rear wheels. A work vehicle jack device configured to extend the extension stroke of the front jack and horizontally support the vehicle body even on an inclined ground by the front and rear jacks,
A jack storage operation means, a front jack reduction detection means for detecting that the front jack has been reduced to a predetermined position, a rear jack non-grounding state detection means for detecting a state in which the ground reaction force does not act on the rear jack, Jack operating means for operating each jack, and jack storing control means for receiving signals from the jack storing operation means, front jack reduction detecting means and rear jack non-grounding state detecting means and outputting control signals to the jack operating means. The jack storage control means receives the storage operation signal from the jack storage operation means, reduces the front jack until the detection signal from the front jack reduction detection means is input, and then detects the rear jack non-ground state. The rear jack is reduced until a detection signal is input from the means, and then the front jack is reduced and the front jack is reduced. Jack device for a working vehicle, characterized by being configured to output a signal to each jack actuating means so as to store each jack by reducing the rear jack causes to elapse ungrounded state. 2. The front jack reduction detection means according to claim 1, comprising a front jack reduction detector that is directly attached to the front jack and detects that the front jack has been reduced to a predetermined position and outputs a detection signal to the jack storage control means. A work vehicle jack device. 2. The front jack contraction detection means according to claim 1, wherein the front jack expansion / contraction length detection means for detecting the expansion / contraction length of the front jack and the front jack expansion / contraction length when the front jack is contracted to a predetermined position are stored. When determining and determining that the front jack has been reduced to a predetermined position in response to signals from the predetermined jack expansion / contraction length storage means, the front jack expansion / contraction length detector and the front jack predetermined expansion / contraction length storage means A jack device for a work vehicle, comprising: a jack reduction determination means for outputting a determination signal to the jack storage control means. 2. The front jack reduction detection means according to claim 1, wherein the front jack reduction time storage means for storing the time for the front jack to reduce to a predetermined position, and the time after receiving the operation start signal of the jack storage operation switch are measured. A jack device for a work vehicle comprising a timer that outputs a time-up signal to the jack storage control means when the measured time reaches the time stored in the previous jack reduction time storage means. 2. The front jack reduction detecting means according to claim 1, wherein the front jack reduction detecting means detects an inclination angle in a longitudinal direction of the vehicle body, an inclination angle storing means for storing an inclination angle when the front jack is reduced to a predetermined position, and an inclination. Pre-jack reduction determination means for receiving a signal from the angle detector and the inclination angle storage means, and determining and determining that the inclination angle of the vehicle body has reached the inclination angle for storage, and outputting a determination signal to the jack storage control means; in jack device for a work vehicle, characterized in that it has configured. 6. The inclination angle setting means operated to store the inclination angle of the vehicle body before grounding the jack, and signals from the inclination angle detector and the inclination angle setting means are arranged in the inclination angle storage means. A jack device for a work vehicle, characterized in that an inclination angle of a vehicle body before grounding a receiving jack is stored as an inclination angle when the front jack is reduced to a predetermined position.

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