JP2007125495A - Jaw crusher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jaw crusher capable of enhancing productivity by suppressing working discontinuation beyond need. <P>SOLUTION: The jaw crusher is provided with a fixed tooth fixed to a crusher frame, a movable tooth pivoted relative to the fixed tooth, a jack fixed to the crusher frame, a relief valve for regulating the maximum value of a pressure of a return conduit of a pressure oil of the jack and contracting/retreating the jack when a load exceeding the regulated maximum pressure is applied, a toggle plate interposed between the jack and the movable tooth, a hydraulic cylinder for urging the movable tooth to the jack side such that the toggle plate is retained between the jack and the movable tooth, a stroke sensor for detecting a stroke of the jack, and a control apparatus for executing a procedure (S130) for stretching the jack by the contracting/retreating degree when the contraction/retreating amount of the jack detected by the stroke sensor exceeds a set value and procedures (S150, S160) for stopping the oscillating action of the movable tooth when as a result, the jack is not returned to an original position. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a jaw crusher for crushing an object to be crushed such as rock.

  A jaw crusher introduces and crushes an object to be crushed into a crushing chamber formed between a fixed tooth and a moving tooth that swings with respect to the fixed tooth. Some jaw crushers of this type are configured to receive a crushing reaction force acting on a moving tooth from an object to be crushed by a lock cylinder (see Patent Document 1). In this prior art, the toggle plate is held between the lock cylinder and the moving tooth so that the crushing reaction force transmitted to the lock cylinder via the toggle plate is received by the friction force between the cylinder tube and the piston rod. It has become.

JP 2003-53203 A

  In the above prior art, when a crushing reaction force exceeding the frictional force between the cylinder tube of the lock cylinder and the piston rod acts on the moving teeth during overload, the lock cylinder is retracted and moves in a direction to expand the crushing chamber outlet. As the teeth retract, the toggle plate is protected from breakage. Therefore, if the lock cylinder is extended to the original state, it can be returned to the crushing operation.

  However, in this prior art, the crushing operation can be resumed only after the crushing device is stopped at the time of overload, and after the foreign matter and the object to be crushed are discharged, the lock cylinder is returned to the original state. . In other words, if the lock cylinder is degenerated, the crushing operation is automatically interrupted, and the crushing operation cannot be resumed until the crushed material in the crushing chamber is completely discharged. As a result, for example, if a non-crushable foreign object such as a reinforcing bar enters the crushing chamber and the load of the crushing device exceeds the set range even for a moment, the crushing operation is forced even if it is only a temporary overload. Will be interrupted.

  The objective of this invention is providing the jaw crusher which can improve productivity by suppressing the operation | work interruption more than necessary.

  In order to achieve the above object, the present invention provides a crushing device frame, a fixed tooth fixed to the crushing device frame, and a crushing chamber formed between the fixed tooth and swinging with respect to the fixed tooth. A moving tooth supported by the crushing device frame via an eccentric shaft, a jack fixed to the crushing device frame in a space opposite to the crushing chamber of the moving tooth, and a pressure oil return pipe of the jack A relief valve that regulates the maximum value of the pressure of the road, and retracts the jack when a load exceeding the prescribed maximum pressure is applied; a toggle plate interposed between the jack and the moving tooth; and the toggle An urging means for urging the moving tooth toward the jack so that the plate is held between the jack and the moving tooth, a stroke sensor for detecting the stroke of the jack, and the stroke sensor A procedure for extending the jack by the amount of degeneration detected when the amount of degeneration of the jack detected by the driver exceeds a set value, and the moving teeth when the jack does not return to the original position as a result of executing this procedure. And a control device for executing a procedure for stopping the swinging motion of the motor.

  According to another aspect of the present invention, in the above-described invention, the feeder further includes a feeder that supplies a material to be crushed to the crushing chamber, and the control device sets a degeneration amount of the jack detected by the stroke sensor. When the value is exceeded, the feeder is stopped before the jack is extended by the detected amount of degeneration.

  According to the present invention, during overload, the jack is degenerated and the toggle plate is protected from breakage. Therefore, the crushing operation can be continued if the jack is returned to the position before degeneration without replacing the toggle plate. it can. At this time, even when the jack is degenerated, the operation is not stopped immediately, the jack is returned to the original position while the crushing device is operated, and the crushing operation needs to be interrupted only when the jack does not return to the original position. By determining and stopping the crushing device 20, the crushing operation is not interrupted if the jack returns to the state before degeneration. In this way, productivity can be improved by suppressing unnecessary work interruptions.

Embodiments of the present invention will be described below with reference to the drawings.
1 is a side view showing the overall structure of a jaw crusher according to an embodiment of the present invention, FIG. 2 is a top view thereof, FIG. 3 is a rear view as viewed from the left side in FIG. 1, and FIG. It is the front view seen from the right side. In the following description, the left and right in FIG. 1 are the rear and front of the jaw crusher or one side and the other side in the longitudinal direction of the main body frame, respectively.
The jaw crusher shown in FIGS. 1 to 4 is a variety of construction waste, industrial waste, or rock mining that occurs at construction sites, such as concrete lumps carried out at the time of building demolition and asphalt lumps discharged at road repairs. It is intended to crush rocks and natural stones that are mined at the site or face, and accept and crush them as objects to be crushed. The jaw crusher includes a traveling body 1 and a crusher main body 2, and has a self-propelled function by providing the traveling body 1 at a lower portion of the crusher main body 2. However, the application target of the present invention is not limited to the jaw crusher having such a self-propelling function, and the present invention can also be applied to a jaw crusher capable of towing and a stationary jaw crusher.

  The traveling body 1 includes a traveling device 3 and a main body frame 4 provided substantially horizontally above the traveling device 3. The travel device 3 has an output shaft on the track frame 5, driven wheels and drive wheels (both not shown) provided at both ends of the track frame 5, a crawler belt 7 hung around the driven wheels and the drive wheels, and the shaft of the drive wheels. The driving device 8 for driving | running | working connected is provided. The track frame 5 is connected to the lower part of the main body frame 4. In the present embodiment, the track frame 5 is formed integrally with the track frame 4.

  The crusher body 2 includes a hopper 12 that receives an object to be crushed (a material to be crushed), a grind feeder 15 that supplies a crushed material received by the hopper 12 to a subsequent process, and a material to be crushed supplied by the grizzly feeder 15. A crushing device 20 for crushing, a discharge conveyor 25 for discharging the crushed material crushed by the crushing device 20 to the outside of the machine, and a power device (power unit) 40 having a built-in power source of an operating device mounted in various parts of the machine body. Yes.

  The hopper 12 is a frame-shaped member that expands upward, and is fixed to the support member 13 provided on the upper portion on one side in the longitudinal direction of the main body frame 4 via support posts 9 and 10.

The grizzly feeder 15 is located below the hopper 12 and is supported by the support member 13 via a spring (not shown) separately from the hopper 12. In the main body 16 of the grizzly feeder 15, a plurality (two in the present embodiment) of grizzly ribs 18 having comb teeth 17 arranged in the width direction of the main body frame 4 (vertical direction in FIG. 2) at the front end are provided. It is fixed in the shape of a staircase that descends toward the front. A feeder driving device 19 that vibrates the grizzly feeder main body 16 is fixed to the lower portion of the grizzly feeder main body 16. When the grizzly feeder main body 16 is vibrated by the feeder driving device 19, The object to be crushed is transported forward, and fine particles (so-called slip) or the like in the object to be crushed smaller than the gap between the comb teeth 17 fall from the gap between the comb teeth 17, and the object to be crushed has a larger particle size. Moves on the comb teeth 17 and is supplied to the crushing device 20.
In addition, a chute 11 is provided below the comb teeth 17 of the grizzly feeder 15, and a slip or the like falling from a gap between the comb teeth 17 is guided to the vicinity of the rear end of the discharge conveyor 25 by the chute 11.

  The crushing device 20 is located in front of the hopper 12 and the grizzly feeder 15 and is supported near the center in the longitudinal direction of the main body frame 4. Although details will be described later with reference to FIG. 5 and the like, the crushing device 20 includes a pair of fixed teeth and moving teeth that face each other so that the gap space (crushing chamber) decreases in diameter toward the lower side. ing. The upper end of the moving tooth swing jaw is connected to a flywheel (not shown), and when the rotational power of the crushing device drive device 21 (see FIG. 2) is transmitted to the flywheel, the flywheel rotates. Is converted into a swinging motion of the moving tooth, whereby the moving tooth swings substantially in the front-rear direction with respect to the fixed tooth.

  The discharge conveyor 25 includes a conveyor frame 26, driven wheels and driving wheels (both not shown) provided at both ends of the conveyor frame 26, a conveyor belt (not shown) wound around the driven wheels and driving wheels, and driving wheels. A drive device (not shown) for a discharge conveyor to be rotated is provided. With this configuration, when the driving wheel is rotationally driven by the discharge conveyor driving device, the conveyor belt wound around the driven wheel is circulated and driven. In this example, such a discharge conveyor 25 is supported by being suspended from the main body frame 4 or the like via the support members 31 and 32 and the like so as to rise obliquely forward from the lower position of the chute 11 through the lower portion of the crushing device 20. ing.

  Above the discharge conveyor 25, there is provided a magnetic separator 35 for removing foreign matters (magnetic materials) such as reinforcing bars in the crushed material to be discharged. The magnetic separator 35 is suspended and supported by an arm member 36 spanned between the main body frame 4 and the conveyor frame 26, and a magnetic separator belt 39 wound around a driving wheel and a driven wheel (not shown) is substantially disposed with respect to the discharge conveyor 25. It is arranged to be orthogonal. A magnetic force generating means (not shown) is provided in the space between the driving wheel and the driven wheel (not shown) covered with the magnetic separator belt 39, and foreign matters such as reinforcing bars are mixed in the crushed material of the discharge conveyor 25. In this case, the foreign matter is attracted to the magnetic separator belt 39 by the magnetic force from the magnetic force generating means acting over the magnetic separator belt 39, and is conveyed to the side of the discharge conveyor 25 by the magnetic separator belt 39 that is circulated and dropped.

  The power device 40 is supported by the other end portion in the longitudinal direction of the main body frame 4 and is located on the front side of the crushing device 20. Although not specifically shown, in the power unit 40, an engine serving as a power source of the jaw crusher, a hydraulic pump 60 driven by the engine (see FIG. 7 described later), and a pressure discharged from the hydraulic pump 60 A control valve 66 and the like are provided to control the oil flow direction and flow rate and supply the oil to the corresponding hydraulic actuator.

5 and 6 are side sectional views showing the internal structure of the crushing device 20, FIG. 5 shows a working state, and FIG. 6 shows a state where the moving teeth are retracted. However, in these drawings, a fixed tooth plate and a movable tooth plate, which will be described later, are not shown.
5 and 6, the crushing device 20 includes a crushing device frame 41 fixed to the main body frame 4, a fixed tooth 42 fixed to the crushing device frame 41, a moving tooth 43 swinging with respect to the fixed tooth, and a moving tooth 43. A toggle plate 44 is provided to support the lower side.

  Strictly speaking, the fixed tooth 42 includes a support member 45 fixed to the crushing device frame 41 and a fixed tooth plate (not shown) fixed to the front surface (moving tooth 43 side) of the support member 45. . The moving teeth 43 are fixed to the crushing device frame 41 with a swing jaw 48 swingably attached via an eccentric shaft 47 of a flywheel (not shown), and a rear surface (fixed tooth 42 side) of the swing jaw 48. And a movable tooth plate (not shown). The moving teeth 43 and the fixed teeth 42 are arranged to face each other so that the tooth plates face each other, and a crushing chamber 49 that decreases in diameter downward is formed between both tooth plates. The object to be crushed supplied to the crushing chamber 49 is crushed so as to be crushed by the fixed teeth 42 and the moving teeth 43 by the swinging movement of the moving teeth 43. The particle size of the crushed material discharged from the crushing device 20 is defined by the lower exit width of the crushing chamber 49, that is, the minimum gap between the fixed tooth plate and the movable tooth plate.

  Here, in the space opposite to the crushing chamber 49 of the moving teeth 43 (right side in FIG. 5), when an overload occurs due to, for example, a foreign matter biting in the crushing chamber 49, the toggle plate 44, etc. An overload protection device 50 that protects these members from an excessive load is installed. The overload protection device 50 includes a jack 51 that retracts from the working state of FIG. 5 as shown in FIG. 6 and releases an excessive crushing reaction force when the crushing reaction force acting on the swing jaw 48 exceeds a set range. (Details will be described later).

  The jack 51 is fixed to the crushing device frame 41, and toggle sheets 53 and 54 are provided at the front end portion of the rod 52 of the jack 51 and the front lower portion of the swing jaw 48, respectively. The toggle sheets 53 and 54 are in contact with both ends of a toggle plate 44 interposed therebetween, and the lower end of the swing jaw 48 is jacked by a hydraulic cylinder 55 (see FIG. 6, not shown in FIG. 5). The toggle plate 44 is held between the toggle sheets 53 and 54 by being biased toward the 51 side. Both ends of the hydraulic cylinder 55 are rotatably connected to the lower part of the jack 51 and the vicinity of the lower end of the front surface of the swing jaw 48. In the present embodiment, the swing jaw 48 is biased toward the jack 51 by the hydraulic cylinder 55, but the swing jaw 48 is biased toward the jack 51 by a spring instead of the hydraulic cylinder 55. Also good.

FIG. 7 is a hydraulic circuit diagram showing an outline of a portion related to driving of the jack 51 in the hydraulic drive device of the jaw crusher of the present embodiment.
The hydraulic drive apparatus shown in FIG. 7 includes a hydraulic pump 60 driven by an engine (or electric motor) (not shown), a control valve 62 and a check valve 63 provided in a discharge pipe 61 of the hydraulic pump 60, and a control valve 62. And the relief valve 66 provided in the return pipe 65 from the jack 51 to the tank 64. The relief valve 66 defines the maximum pressure of the return line 65 of the pressure oil of the jack 51 by the biasing force of the spring 66a, and the maximum pressure defined by the pressure of the return management 65 that rises in response to the crushing reaction force. When it exceeds, it plays the role which makes the return pipe line 65 communicate with the tank 64, and degenerates the jack 52, and comprises the previous overload protection apparatus 50 with the jack 51. FIG.

  In the hydraulic drive device shown in FIG. 7, when a drive signal is input from a control device (described later) to the solenoid unit 62 c and the control valve 62 is switched to the communication position 62 b, the chamber 51 a on the bottom side of the hydraulic pump 60 and the jack 51. And the bottom chamber 51a of the jack 51 is pressurized by the pressure oil discharged from the hydraulic pump 60, and acts to push out the rod 52 and extend the jack 51.

  On the other hand, in the normal state, the control valve 62 is in the state of the blocking position 62a by the urging force of the spring 62d and blocks the flow of pressure oil in the discharge pipe 61. When the control valve 62 is at the shut-off position 62a as shown in FIG. 7, the pressure oil supply / discharge path to the jack 51 is closed, so that the stroke of the jack 51 is maintained at that time. However, during the crushing operation, the crushing reaction force acting on the swing jaw 48 from the object to be crushed in the crushing chamber 49 acts on the rod 52 of the jack 51 via the toggle plate 44, so that the crushing reaction force is transmitted to the rod 52. Then, a force acts to push the pressure oil in the chamber 51a on the bottom side of the jack 51 out of the chamber 51a.

  If the crushing reaction force does not exceed the set value, the relief valve 66 is in the blocking position by the biasing force of the spring 66a, so that the pressure in the bottom side chamber 51a of the jack 51 even if the crushing reaction force acts on the rod 52. The oil is sealed in the pipe line between the check valve 63 and the relief valve 66, and the stroke of the rod 52 is maintained as it is.

  However, when the crushing reaction force transmitted to the rod 52 exceeds the set value, the pressure in the return pipe 65 is increased by the pressure oil pushed away from the bottom side chamber 51a of the jack 51, and the pressure increases the biasing force of the spring 66a. If it exceeds, the relief valve 66 will switch to a communicating position. As a result, the chamber 51a of the jack 51 and the tank 64 are connected via the return pipe 65, and the pressure oil in the chamber 51a is discharged until the pressure of the return pipe 65 falls below the urging force of the spring 66a. The rod 52 retreats by the discharge flow rate, and the jack 51 retracts.

  At this time, in the present embodiment, the jack 51 is provided with a stroke sensor 70 that detects the stroke position (or stroke amount) of the rod 52. The stroke position of the rod 52 detected by the stroke sensor 70 is output to the control device 80.

FIG. 8 is a block diagram of the control device 80.
In FIG. 8, the control device 80 receives a detection signal of the stroke sensor 70 and converts it into a digital signal, an analog input unit (A / D converter) 81, for example, an operation switch of an operation panel (not shown) provided in the machine body A digital input unit 82 for inputting an operation signal from 71, a temporary storage unit (RAM) 83 for temporarily storing a detection value or the like detected by the stroke sensor 70 input to the analog input unit 81, programs and constants necessary for control, etc. Is stored in a storage unit (ROM) 84, an arithmetic control unit (CPU) 85 that calculates various command values according to a desired program read from the storage unit 84 based on a detection signal input to the analog input unit 81, and an arithmetic control unit The command value from 85 is input, and a display signal to the display unit 72 provided on the operation panel is calculated and output, or input from the display unit 72 by a touch operation on the screen. A display control unit 86 for inputting operation signals, a digital output unit 87 for inputting command values from the arithmetic control unit 85 and outputting command signals to the solenoid unit 62c of the control valve 62 and other operating devices, and time measurement A timer 88 is provided.

  The storage unit 84 includes a procedure for extending the jack 51 by the detected amount of contraction when the amount of contraction of the rod 52 of the jack 51 detected by the stroke sensor 70 exceeds a set value, and a jack as a result of executing this procedure. A program for causing the arithmetic control unit 85 to execute a procedure for stopping the swinging motion of the moving tooth 43 when 51 does not return to the original position is stored. Further, in the present embodiment, when the amount of contraction of the jack 51 detected by the stroke sensor 70 exceeds the set value, the storage unit 84 stores the grizzly feeder 15 before extending the jack 51 by the detected amount of contraction. A program for causing the arithmetic control unit 85 to execute the procedure for stopping is also stored.

Next, the operation of the jaw crusher of the present embodiment having the above configuration will be described.
When the object to be crushed is put into the hopper 12 by a hydraulic excavator or the like, the thrown object to be crushed is guided onto the grizzly feeder 15 and conveyed toward the crushing device 20 by vibration. At that time, fine grains (slipping etc.) smaller than the gaps between the comb teeth 17 of the grizzly river 18 are guided to the discharge conveyor 25 through the chute 11 from the gaps, and a larger object to be crushed (large lump). Is supplied to the crushing device 20. The object to be crushed supplied to the crushing device 20 is crushed to a predetermined particle size corresponding to the exit gap between the fixed tooth 42 and the moving tooth 43 and introduced onto the lower discharge conveyor 25. The crushed material guided onto the discharge conveyor 25 merges with the fine particles guided through the chute 11 and is conveyed forward (right side in FIG. 1), and adsorbs foreign matter such as reinforcing bars by the magnetic separator 35 in the middle. After being removed, it is discharged out of the machine.

  Here, the crushing reaction force that the moving teeth 43 receive from the object to be crushed during the crushing operation is transmitted to the rod 52 via the toggle plate 44. When the crushing reaction force is within the set value defined by the relief valve 66, the pressure oil in the bottom side chamber 51 a of the jack 51 is sealed in a pipe line between the relief valve 66 and the check valve 63. Therefore, the stroke of the rod 52 of the jack 51 is maintained in the state at that time.

  However, during the crushing operation, for example, a non-crushable foreign material such as a reinforcing bar is supplied to the crushing chamber 49 or the material to be crushed into the crushing chamber 49 becomes excessively supplied, resulting in an overload state. . In this way, if the crushing reaction force applied to the swing jaw 48 exceeds the set value defined by the relief valve 66, the overload protection device 50 is activated and the jack 51 is degenerated as described above. This avoids an overload condition and protects the toggle plate 44 from breakage.

  At this time, in the jaw crusher of the present embodiment, when the overload protection device 50 is activated, the jack 51 is immediately returned to the original position while continuing the crushing operation without interrupting the crushing operation. If the stroke of the jack 51 does not return to the original position during the time, the crushing operation is interrupted.

FIG. 9 is a flowchart showing the airframe control procedure when the controller 80 is overloaded.
9, first, for example, when an operation switch 71 of an operation panel (not shown) is operated and an operation signal instructing start of operation is input to the digital input unit 82, the input operation signal is input in step 100. In accordance with the program stored in the storage unit 84, the arithmetic control unit 85 generates a command signal to the drive device of each operating device (grid feeder 15, crushing device 20, discharge conveyor 25, magnetic separator 35, etc.), and the command signal Is output to each driving device via the digital output unit 87, and each actuating device operates.

  During operation, detection signals from sensors provided in various parts of the machine body are input to the control device 80 at any time (or every set time). When a detection signal from the stroke sensor 70 is input to the analog input unit 81 during operation, the detection value converted into a digital signal is stored in the temporary storage unit 83 and the detection value stored in the temporary storage unit 83 is also determined. The stroke position X of the rod 52 of the jack 51 calculated by the calculation control unit 85 is sequentially stored in the temporary storage unit 83.

  Thus, during operation, the stroke position X of the rod 52 of the jack 51 is monitored by the control device 80, and in the subsequent step 110, the calculated stroke position X of the rod 52 is stored in the storage unit 84. It is determined by the arithmetic control unit 85 whether or not As a result, if it is determined that the stroke position X has not reached the set position X1, the procedure returns to step 100 to continue the current operation state, and it is determined that the stroke position X has reached the set position X1. If so, the procedure proceeds to step 120.

  When the procedure moves to step 120, the control device 80 outputs a stop signal to the feeder drive device 19 to stop the grizzly feeder 15, interrupts the supply of the object to be crushed to the crushing device 20, and moves to step 130. To do.

  In step 130, the control device 80 corrects the stroke position X of the rod 52 to return the rod 52 to the original position. Specifically, the control device 80 generates a command signal for extending the jack 51 and outputs the command signal to the solenoid unit 62 c of the control valve 62 via the digital output unit 87. As a result, the control valve 62 is switched to the communication position 62b, and the outlet side chamber 51a of the jack 51 is pressurized to extend the jack 51.

  In subsequent step 140, the control device 80 compares the detected stroke position X of the rod 52 after correction with the stroke position (original position) X 0 of the rod 52 at the start of operation stored in the temporary storage unit 83. It is determined whether or not two values are equal (the two values are not completely identical, and it is desirable to set an allowable range for the error). As a result, when it is determined that the rod 52 has returned to the original position X0, the procedure returns to step 100, and a command signal for driving the feeder drive device 19 is output, and the grizzly feeder 15 is activated again for crushing. Supply of the material to be crushed to the apparatus 20 is resumed. Even if an overload state occurs until this point, the grizzly feeder 15 is stopped and the supply of the object to be crushed to the crushing device 20 is temporarily performed during the execution of the procedure of Step 120 → Step 130 → Step 140 → Step 100. The operation of the crushing device 20 is continued only by interruption.

  On the other hand, if it is determined in step 140 that the stroke position X of the rod 52 has not returned to the original position X0, the control device 80 moves the procedure to step 150 and moves the rod 52 to the original position based on the measurement time of the timer 88. In order to return to the position X0, in step 130, it is determined whether or not the elapsed time T from the output of the command signal to the solenoid unit 62c exceeds the set time T1. If the set time T1 has not elapsed at that time, the procedure returns to step 130, and a command signal is output again to the solenoid unit 62c to return the rod 52 to the original position X0.

  However, in step 150, if the set time T1 has passed without the rod 52 returning to the original position X0, the control device 80 proceeds to step 160. In step 160, a command signal for stopping the other operation devices (the crushing device 20, the discharge conveyor 25, the magnetic separator 35, etc.) is generated and output to each driving device via the digital output unit 87 to perform the crushing operation. The process is interrupted and the procedure of FIG.

  Although not specifically shown in the flowchart of FIG. 9, the control device 80 sequentially stores the stroke position X of the rod 52 in the temporary storage unit 83 and also displays the control panel display unit 72 and the like via the display control unit 86. A display signal may be output to the operator to sequentially notify the stroke position X of the rod 52 to the operator. Further, instead of sequentially displaying the stroke position X, it may be displayed that the crushing device 20 is in an overload state, that is, that the overload protection device 50 is in operation. In this case, for example, it is conceivable that a visual or audible notification is performed from the time when X ≧ X1 is determined at step 110 to the time when X = X0 is determined at step 140. As the visual notification, for example, it is conceivable to display character information indicating that fact on the display unit 86, or display it using light or color on the display unit 86 or a warning light (not shown). As an auditory notification, a notification by voice or a warning sound can be considered.

According to this embodiment described above, the following various effects can be obtained.
(1) Improvement of productivity In this embodiment, when overload occurs, the jack 51 is retracted and the toggle plate 44 is not broken. Therefore, even if the toggle plate 44 is not replaced, the jack 51 can be returned to the position before the contraction. The crushing operation can be continued. At this time, in the present embodiment, even when the jack 51 is retracted, the operation is not immediately stopped, and only when the jack 51 is returned to the original position while the crushing device 20 is operated and is not returned to the original position. It is judged that it is necessary to interrupt the crushing operation, and the crushing device 20 is stopped. That is, if the jack 51 returns to the state before the contraction, the crushing device 20 is continuously operated until then, and the crushing operation is not interrupted.

  If the crushing operation is interrupted in the event of an overload, for example, if the crushing operation is continued even though relatively small foreign matter is supplied to the crushing chamber 49, the foreign matter is naturally discharged. In this embodiment, the crushing operation can be continued and returned to the normal load state when the crushing operation can be released naturally if the crushing operation is continued simply by falling into an excessive supply state. it can. Thus, according to the present embodiment, productivity can be improved by suppressing unnecessary work interruptions.

  Further, if foreign matter is mixed into the crushing chamber 49 and the overload reaction device 50 is operated and the crushing device 20 is stopped immediately, the material to be crushed remains in the crushing chamber 49. When discharging foreign matter or resuming crushing work, a great deal of labor is required to discharge the object to be crushed from the crushing chamber 49. On the other hand, in the case of the present embodiment, even if a foreign object that needs to stop the crushing device 20 is supplied to the crushing chamber 49, the set time after the overload protection device 50 is activated. Since the crushing device 20 operates in a state where the outlet of the crushing chamber 49 spreads during the lapse of time, it is highly possible that most of the material to be crushed is discharged during that time. This can also be expected to reduce the labor required to interrupt and restart the crushing operation.

  Even if the stroke of the jack 51 changes due to the leakage of pressure oil to the control valve 62, the jack 51, etc., not in the case of falling into an overload state, if the stroke exceeds the set value It is also an advantage that the control procedure of FIG. 9 is executed and the crushing conditions can be returned to the set conditions.

(2) Improving the operational stability of the overload protection device For example, when an overload protection device is constructed using a lock cylinder or the like, the maximum value of the crushing reaction force on the toggle plate (that is, the operating pressure of the overload protection device) is locked. It is defined by the maximum static friction force acting between the cylinder rod and cylinder tube. Therefore, if the overload protection device is activated repeatedly, the maximum static frictional force between the rod and the cylinder tube is reduced accordingly, and the allowable value of the crushing reaction force applied to the toggle plate is less than the originally assumed condition. There is a risk that the overload protection device operates more than necessary and the productivity is lowered.

  On the other hand, in the present embodiment, the maximum value of the crushing reaction force applied to the toggle plate 44 is defined by the biasing force of the spring 66a of the relief valve 66, so that the overload protection device 50 may be repeatedly activated. However, the operating conditions are constant, and it is possible to improve productivity and suppress fluctuations in the particle size of the crushed material. In addition, when the overload protection device 50 is activated, even if the bottom chamber 51 a of the jack 51 is pressurized, the pressure of the pressure oil pipes 61 and 65 may exceed the protection pressure defined by the relief valve 66. Therefore, when the rod 52 is returned to the original position, it is possible to prevent the jack 51 and the toggle plate 44 from being pressurized more than the set value.

  In addition, the lock cylinder uses a tight fitting force as the holding force of the rod, and when the rod is slid, it expands the inner diameter of the cylinder tube and weakens the clamping force to pressurize the rod chamber. When doing so, the holding power of the rod is reduced. On the other hand, in the present embodiment, the holding force of the rod 52 is defined by the spring 62a of the relief valve 66. Therefore, as long as the pressure oil is sealed in the circuit, it changes regardless of whether the jack 51 is operated or not. Absent. Accordingly, in the present embodiment, the crushing device 20 is continuously operated while the set time elapses even at the time of overload. In such a case, the rod 52 can be operated under the same conditions as those at the time of holding.

(3) Simplification of structure When an overload protection device is configured using a lock cylinder, the lock cylinder requires a hydraulic system for expansion and contraction and a hydraulic system for applying a friction force for holding the rod. The drive circuit becomes so complicated. Further, since the lock cylinder itself is an expensive device, the manufacturing cost of the hydraulic drive device also increases.

  On the other hand, in the present embodiment, the holding force of the jack 51 is ensured by the relief valve 66, so that the jack 51 alone is sufficient as the driving device of the overload protection device 50, and the structure of the overload protection device is simplified. Therefore, even when the jack 51, the relief valve 66, etc. deteriorate due to aging, the parts can be easily replaced. Moreover, since the jack 51 is sufficient as a normal thing, it contributes also to the cost reduction of a hydraulic drive device.

(4) Others For example, if a pressure sensor is provided in the bottom chamber 51a of the jack 51 or a pipe line between the relief valve 66 and the check valve 63 so that the internal pressure can be monitored, the rod 52 can be held. The pressure can be confirmed. Therefore, for example, it is possible to adjust the operation accuracy of the overload protection device 50 by monitoring the pressure when the overload protection device 50 is operated and adjusting the biasing force of the spring 66a of the relief valve 66 based on the result. it can.

  As described above, in the present embodiment, when the overload protection device 50 is activated, when the rod 52 of the jack 51 is returned to the original position, the grizzly feeder 15 is stopped in advance and the material to be crushed to the crushing device 20 is transferred. The jack 51 is easily extended by interrupting the supply, but it is not always necessary to stop the grizzly feeder 15 as long as the jack 51 is extended while continuing the crushing operation. The presence or absence of this procedure needs to be examined in advance together with the setting of the length of the set time T1 in FIG. 9, taking into consideration the risk of breakage of the toggle plate 44.

It is a side view showing the whole structure of the jaw crusher concerning one embodiment of the present invention. It is a top view showing the whole structure of the jaw crusher which concerns on one embodiment of this invention. It is a rear view showing the whole structure of the jaw crusher concerning one embodiment of the present invention. It is a front view showing the whole structure of the jaw crusher concerning one embodiment of the present invention. It is a sectional side view showing the internal structure of the crushing device with which the jaw crusher concerning one embodiment of the present invention was equipped. It is a sectional side view showing the internal structure of the crushing device with which the jaw crusher concerning one embodiment of the present invention was equipped. 1 is a hydraulic circuit diagram that extracts and represents an outline of a portion related to driving of a jack in a hydraulic drive device for a jaw crusher according to an embodiment of the present invention. It is a block diagram of a control device provided in a jaw crusher according to an embodiment of the present invention. It is a flowchart showing the body control procedure at the time of the overload by the control apparatus with which the jaw crusher which concerns on one embodiment of this invention was equipped.

Explanation of symbols

15 Grizzly feeder 41 Crusher frame 42 Fixed teeth 43 Moving teeth 44 Toggle plate 47 Eccentric shaft 49 Crushing chamber 51 Jack 55 Hydraulic cylinder 65 Return line 66 Relief valve 70 Stroke sensor 80 Control device

Claims (2)

A crusher frame;
Fixed teeth fixed to the crusher frame;
A moving tooth supported on the crushing device frame via an eccentric shaft so as to form a crushing chamber between the fixed tooth and swing with respect to the fixed tooth;
A jack fixed to the crushing device frame in a space opposite to the crushing chamber of this moving tooth;
A relief valve that regulates the maximum pressure of the return line of pressure oil of the jack, and retracts the jack when a load exceeding the prescribed maximum pressure is applied;
A toggle plate interposed between the jack and the moving tooth;
An urging means for urging the moving tooth toward the jack so that the toggle plate is held between the jack and the moving tooth;
A stroke sensor for detecting the stroke of the jack;
The procedure of extending the jack by the amount of degeneration detected when the amount of degeneration of the jack detected by the stroke sensor exceeds a set value, and the case where the jack does not return to the original position as a result of executing this procedure. A jaw crusher comprising: a control device that executes a procedure for stopping the swinging motion of the moving tooth.   The feeder further includes a feeder that supplies the object to be crushed to the crushing chamber, and the control device detects the amount of reduction detected when the amount of reduction of the jack detected by the stroke sensor exceeds a set value. The jaw crusher according to claim 1, further comprising a step of stopping the feeder before extending the jack only.

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