JP5916442B2 - Slug dump truck - Google Patents

Description

  The present invention relates to a slag dump truck that transports, loads and unloads slag pots (slag pots) such as steelworks, and more particularly, to a slag dump truck provided with a pot cover (pan lid) that can be opened and closed.

  Conventionally, as shown in FIG. 5, a boom 2 having a hook 1 at its tip, a boom cylinder 3 that rotates the boom 2 around a rotation shaft 2 a, and a pot cover 5 that is pivotally supported by the mast 4. And the slag dump truck 7 provided with the pot cover cylinder 6 which rotationally drives the pot cover 5 is known (patent documents 1, 2, non-patent documents 1, etc.).

  The slag dump truck 7 shown in FIG. 5 rotates the boom 2 around the rotary shaft 2a by hooking the hook 1 on the trunnion pins 9 projecting from the left and right of the slag pot 8 and driving the boom cylinder 3. Thus, the slag pot 8 is loaded on the loading platform 10, or the slag pot 8 is loaded or unloaded from the loading platform 10 or is in a draining posture.

JP 2002-316793 A JP 2002-67775 A

TCM Corporation website (Web page introducing slag dump trucks), [Search February 22, 2012], Internet (http://www.tcm.co.jp/products/lineup/03/02.html)

  In a slag dump truck equipped with a pot cover, it is possible that the pot cover may come into contact with an elevated or the like when traveling with the pot cover open.Therefore, as a safety device, the boom can be operated when the pot cover is open. It is desirable to provide an interlock (first interlock) that can be used but cannot travel.

  In addition, when the slag pot is mounted on the loading platform when the pot cover is closed, the slag pot collides with the pot cover. Therefore, as a safety device, the vehicle can run when the pot cover is closed, but the boom operates. It is desirable to provide an interlock (second interlock) that prevents this.

  On the other hand, when there are two types of interlocks as described above, it takes time to fine-tune the width adjustment when the slag dump truck is brought closer to the slag pot in order to mount the slag pot placed on the ground on the loading platform. . For example, the width alignment is performed according to the following procedure.

  Advance the slag dump truck to the position where the boom hook is hooked on the trunnion pin of the slag pot. At this time, if the pot cover is open, the first interlock works and the vehicle cannot run, so the pot cover is closed. The slag dump truck is slowly moved so that the trunnion pin is not impacted by the hook.

  When you think you have reached the hooked position, open the pot cover to activate the boom. This is because if the pot cover remains closed, the boom does not operate due to the second interlock.

  When the pot cover is opened and the boom is operated slightly, if it is found that the position of the hook is slightly deviated from the appropriate position, the slag dump truck needs to be moved back and forth slightly. However, if the pot cover is open, the vehicle cannot travel due to the first interlock. Therefore, the slag dump truck must be moved again after the pot cover is closed.

  As described above, since there is an interlock as a safety device, it is necessary to repeatedly open and close the pot cover when finely adjusting the position of the hook, and the width adjustment work becomes complicated and workability is reduced.

  Then, this invention makes it the main objective to provide the slag dump truck which can avoid the fall of workability | operativity, without impairing the safety | security of the safety device (interlock) provided by providing a pot cover.

  In order to achieve the above object, the present invention is a slag dump truck comprising a boom having a hook at its tip and a pot cover, the first interlock disabling travel when the pot cover is open, A second interlock that disables the operation of the boom when the pot cover is closed, and an automatic return pushbutton switch that releases the first interlock only while the pot cover is pressed are provided.

  The first interlock includes a first detector that detects that the pot cover is in an open position, and a first interlock that disables running of the slag dump truck when the first detector detects the open position. A second solenoid for detecting that the pot cover is in a closed position, and operating the boom when the second detector detects the closed position. A second interlock solenoid for disabling, the automatic return pushbutton switch being connected in series with the first interlock solenoid so as to cut off the energization to the first interlock solenoid only while being pressed. It is preferable that it is comprised.

  Preferably, the first interlock is configured to operate the braking device for the slag dump truck when the first detector detects an open position.

  The braking device is preferably a foot brake.

  The automatic return type push button switch is configured such that the other hand is restrained to push the automatic return type push button switch when operating the operation lever or the steering handle of the boom with one hand. It is preferable that the boom is disposed at a position away from the operation lever and the steering handle of the boom.

  According to the present invention, the first interlock that disables running when the pot cover is open is temporarily released, thereby avoiding a decrease in workability without impairing the safety of the interlock. Can do.

It is a circuit diagram which shows an example of the interlock circuit of the slag dump truck which is a component of this invention. It is a top view which shows the driver's seat interior of a slag dump truck. FIG. 2 is a system diagram conceptually showing a pneumatic system and a hydraulic system of a slag dump truck. It is a hydraulic circuit diagram which shows the example of the full power brake of a slag dump truck. It is a side view which shows the external appearance of a slag dump truck.

  Hereinafter, an embodiment of a slag dump truck according to the present invention will be described with reference to FIGS. However, since the external configuration of the slag dump truck 7 is the same as that of the conventional slag dump truck 7 shown in FIG. 5, refer to FIG. 5 for the external configuration. In addition, the same code | symbol is attached | subjected to the same component through all drawings including the prior art.

  FIG. 1 is an electric circuit diagram showing an interlock circuit of a slag dump truck 7 having a pot cover 5. The interlock circuit includes a first interlock 11 that prevents travel when the pot cover 5 is open, and a second interlock 12 that prevents the boom 2 from operating when the pot cover 5 is closed. And an automatic return type push button switch 13 as a release switch for releasing the first interlock 11 only while it is being pressed.

  The first interlock 11 includes a first proximity switch 14 as a first detector that detects that the pot cover 5 is in the open position, and a first relay 15 that is energized when the first proximity switch 14 is turned on. And a pair of indicator lamps 16 and 17 for displaying that the pot cover 5 is in the open position when the first relay 15 is turned on, and energizing when the first relay 15 is turned on. And a first interlock solenoid 18 for disabling the travel of the slag dump truck 7.

  The automatic return type push button switch 13 is a normally closed type automatic return type push button switch, and is connected in series to the wiring 19 to which the first interlock solenoid 18 is connected. Shut off the power to the.

  The second interlock 12 includes a second proximity switch 20 as a second detector that detects that the pot cover 5 is in the closed position, and a second relay 21 that is energized when the second proximity switch 20 is turned on. When the second relay 21 is turned on, a pair of display lamps 22 and 23 that indicate that the pot cover 5 is in the closed position by energizing and when the second relay 21 is turned on are energized. And a second interlock solenoid 24 for disabling the operation of the boom 2.

  Since the slag dump truck 7 generally has steering handles 25 and 26 (see FIG. 2) on the front side and rear side (work machine side), the indicator lamps 16, 17, 22, and 23 are on the front side. And on the rear side. In FIG. 2, S is a rotatable seat, and L1 and L2 are shift levers for switching between forward / reverse and neutral.

  The first and second proximity switches 14 and 20 are not limited to the installation location as long as the opening and closing of the pot cover 5 can be detected. .

  For example, as shown in FIG. 3, the first interlock solenoid 18 is provided in a bypass path 31 that bypasses the dual brake valve 30 operated by the foot brake pedal 29 when the braking device is an air over hydraulic brake. The solenoid of the closed electromagnetic valve 32 can be used. In FIG. 3, 33 is an air compressor, 34 is an air tank, 35 is an air master (brake booster), 36 is a hydraulic unit (hydric booster), 37 is a wheel cylinder, and 38 is a brake shoe.

  The first interlock 11 preferably operates a foot brake capable of obtaining a strong braking force. However, the first interlock 11 is not limited to the foot brake as long as the slag dump truck 7 can be disabled. For example, instead of the foot brake or together with the foot brake, other braking devices such as a side brake and an exhaust brake may be operated. Alternatively, the forward / reverse cut-off relay 46 is interposed in the power supply wiring of the forward drive valve 41a and the reverse drive valve 41b that are normally closed solenoid valves that supply hydraulic oil to the forward clutch and the reverse clutch, The first interlock solenoid 18 may be used as the solenoid, and the shift may be neutrally controlled by the forward / reverse cut-off relay 46. Alternatively, although not shown, a normally open solenoid valve is interposed in the clutch hydraulic oil supply oil passage of the transmission, and the normally open solenoid valve is closed by using the solenoid of the normally open solenoid valve as the first interlock solenoid 18. The clutch may be disengaged. Further, as shown in FIG. 4, in the case of a full hydraulic type full power brake, a bypass oil passage 64 that bypasses the brake valve 63 interposed in the brake oil supply passages 60 and 61 is provided. The front brake 66 and the rear brake 67 are operated by opening the normally closed solenoid valve 65 by interposing the normally closed solenoid valve 65 and using the solenoid of the normally closed solenoid valve 65 as the first interlock solenoid 18. You may do it. In FIG. 4, 68 is an oil tank, 69 is a pump, 70 and 71 are accumulators, 72 is a foot brake pedal, 73 is a parking brake valve, and 74 is a parking brake.

  For example, as shown in FIG. 3, the second interlock solenoid 24 can be a solenoid of a normally open solenoid valve 40 interposed in a hydraulic circuit 39 that feeds hydraulic oil to the boom cylinder 3. Alternatively, as shown in FIG. However, a solenoid of a cutoff relay that cuts off the power supply to the electromagnetic control valve that controls the supply of hydraulic oil to the boom cylinder 3 may be used. In the figure, E is an engine, 41 is a transmission with a torque converter, 42 is a hydraulic pump, 43 is an oil tank, and 44 is an oil control valve.

  According to the above configuration, when the first proximity switch 14 detects that the pot cover 5 is in the open position, the first relay 15 is turned on and the first interlock solenoid 18 is energized, thereby causing the normally closed electromagnetic The valve 32 is switched to open, compressed air is sent from the air tank 34 through the bypass path 31 to the air master 35, the hydraulic unit 36 is operated, and the hydraulic oil of the hydraulic unit 36 is supplied to the wheel cylinder 37. The brake shoe 38 is pushed out and the foot brake 29 is operated, and the running is disabled. In this way, a braking device operating circuit for operating the foot brake 29 is configured based on the detection signal of the first proximity switch 14 as a detector for detecting the open position of the pot cover 5.

  When the first proximity switch 14 (FIG. 1) is ON, the second proximity switch 20 is OFF, and the second relay 21 and the second interlock solenoid 24 are not energized. First, the boom 2 is operable. In this state, the foot brake 29 is operated by energizing the first interlock solenoid 18, but the energization to the first interlock solenoid 18 is cut off while the automatic return pushbutton switch 13 is being pressed. Therefore, the operation of the foot brake 29 is released, and the vehicle can travel.

  Therefore, in order to load the slag pot 8 installed on the ground or the like on the loading platform of the slag dump truck 7, first, the slag dump truck 7 is caused to travel to the slag pot 8 with the pot cover 5 in the closed position. Move closer and slowly approach from a certain distance. That is, when the pot cover 5 is in the closed position, the second interlock 12 is activated, and when the second proximity switch 20 detects the closed position of the pot cover 5, the second relay 21 is turned on to establish a contact connection. Since the second interlock solenoid 24 is energized and the normally open solenoid valve 40 is closed, the hydraulic oil supply to the boom 2 is cut off and the boom 2 cannot be operated, but the first interlock 11 is working. You can run because there is no.

  When the width has been reduced to some extent, the pot cover 5 is opened to release the second interlock 12 in order to operate the boom 2. When the positional relationship between the slag pot 8 and the hook 1 is not in the proper position when the boom 2 is actuated slightly, it is necessary to further finely adjust the positional relationship. Since the interlock 11 is activated and the vehicle cannot travel, the automatic return type push button switch 13 is pushed so that the vehicle can travel primarily and the width is adjusted. Since no release button for temporarily releasing the second interlock 12 is provided, a human error such as loading the slag pot 8 while the pot cover 5 is closed is avoided.

  When the fine adjustment of the positional relationship between the slag pot 8 and the hook 1 is completed, the outrigger 50 is extended to fix the slag dump truck 7, the boom 2 is operated, and the loading operation of the slag pot 8 is started.

  The automatic return pushbutton switch 13 for temporarily releasing the first interlock 11 is arranged at a position away from the operation lever 45 (FIG. 2) and the steering handle 26 of the boom 2 on the rear side (working machine side). Can be done. In the example shown in FIG. 2, the automatic return pushbutton switch 13 is arranged alongside the wiper switch 47 and the like on the operation panel on the right side toward the steering handle 26.

  As described above, the automatic return type push button switch 13 is arranged at a position away from the operation lever 45 and the steering handle 26 of the boom 2, so that the vehicle can be operated with the left hand to run with the pot cover 5 opened. It is necessary to operate the handle 26 and keep the right hand pressing the automatic return pushbutton switch 13. This is intended to be used only when the positional relationship between the slag dump truck 7 and the slag pot 8 is finely adjusted. With this arrangement, the first interlock 11 is released. To continue, the right hand is restrained, so that traveling and boom operation cannot be performed simultaneously. For example, if the boom 2 can be operated during reverse travel with the pot cover 5 open, the slag dump truck 7 moves back and forth with the hook 1 hooked on the trunnion pin 9 of the slag pot 8 installed on the ground or the like. There is a risk that the slag pot 8 containing the high-temperature slag will be pushed down and the slag pot 8 may be brought down, but such a situation is prevented by preventing the running and the boom operation from being performed simultaneously. . That is, with such an arrangement, workability can be improved while maintaining the safety of the first interlock 11 as a safety device.

  The present invention is not limited to the above embodiment, and various modifications can be employed without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Hook 2 Boom 5 Pot cover 11 1st interlock 12 2nd interlock 14 1st proximity switch (detector)
13 Automatic return type push button switch 26 Steering handle 45 Operating lever

Claims (4)

A boom having a hook at the tip, a pot cover, a first interlock that prevents travel when the pot cover is open, and a first interlock that prevents the boom from operating when the pot cover is closed. 2 interlocks, and an automatic return pushbutton switch that releases the first interlock only while it is being pressed ,
The second interlock is provided so as not to be released,
The automatic return type push button switch is configured such that the other hand is restrained to push the automatic return type push button switch when operating the operation lever or the steering handle of the boom with one hand. A slag dump truck disposed at a position away from the operation lever of the boom and the steering handle . The first interlock includes a first detector that detects that the pot cover is in an open position, and a first interlock that disables running of the slag dump truck when the first detector detects the open position. A locking solenoid, and
The second interlock includes a second detector that detects that the pot cover is in the closed position, and a second interlock that disables the operation of the boom when the second detector detects the closed position. A solenoid, and
2. The slag dump truck according to claim 1, wherein the automatic return type push button switch is connected in series with the first interlock solenoid and cuts off the power supply to the first interlock solenoid only while being pressed. .   The slag dump truck according to claim 2, wherein the first interlock operates a brake device of the slag dump truck when the first detector detects an open position. The slag dump truck according to claim 3, wherein the braking device is a foot brake.

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