JPH04137164U - Cylinder end position detection device - Google Patents

Abstract

(57) [Summary] [Purpose] If a construction machine with a crusher attached to the tip of the work attachment performs crushing work with the bucket cylinder in the stroke end state, the bucket cylinder and other parts of the work attachment may be damaged. be. Therefore, it is necessary to stop the bucket cylinder at the cylinder end position, which is slightly before the stroke end. The present invention provides a detection device that can solve the above problems. [Configuration] In the present invention, the proximity sensor is fixed to the side plate at the tip of the arm, while the upper and lower non-detection holes are drilled at the base end of the idler link, and the loading member is fixed in both holes. The plate was formed so that there were no recesses on the outer peripheral surface. In addition, a wiper cylinder was fitted around the outer periphery of the proximity sensor to prevent foreign matter from entering the front side of the proximity sensor. Also, when the harness leading to the proximity sensor is de-energized, an alarm will be issued.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is mainly used for work attachments of construction machines and work vehicles such as hydraulic excavators. This invention relates to a cylinder end position detection device for a hydraulic cylinder installed in a vehicle.

0002

[Conventional technology]

FIG. 10 is a side view of the construction demolition hydraulic excavator 2 to which the crusher 1 is attached. In the figure, 3 is the work attachment, and 4 is the joint boom of work attachment 3. , 5 is a relay boom, 6 is an arm, 7 is an idler link, 8 is a push rod, 9 is a bucket cylinder that rotates the crusher 1 in the front-back direction, and 10 is a building to be demolished. etc. are constructs. Therefore, the crusher 1 is attached to the work attachment 3 of the hydraulic excavator 2. It is attached to the end and can be rotated back and forth by the expansion and contraction of the bucket cylinder 9. That's what I do.

0003

[Problem that the idea aims to solve]

A hydraulic excavator with a crusher attached to the tip of the work attachment is carrying out a bucket series. If you perform crushing work with the cylinder at the end of its stroke, a much greater crushing force will be generated. It exerts a force on the components of the work attachment, such as the bucket cylinder or other work attachment. It may damage various parts of the touchment. For this purpose, the stroke of the bucket cylinder is Detects the cylinder end position slightly, for example, several tens of millimeters before the cylinder end. Various means (not shown) are being considered. This invention solves the above problems The object of the present invention is to provide a cylinder end position detection device that can detect the cylinder end position.

0004

[Means to solve the problem]

This invention is designed to install the idler link on the side plate of the arm at the end of the arm. The proximity sensor is fixedly provided, and the outer peripheral surface is circular on the inner side of the base end of the idler link. A cylindrical ring plate is fixed and installed, and the outer circumferential surface of the ring plate is attached to the idler link rocker. When the bucket cylinder is moved, the proximity sensor can detect it, and the bucket cylinder is connected to the telescopic straw. Proximity sensor and ring when activated at predetermined positions slightly in front of each other. An upper non-detection hole and a lower non-detection hole are installed on the outer periphery of the ring plate, which faces the outer periphery of the plate. A hole is drilled, and the upper and lower non-detection holes are made non-dielectric or non-magnetic, respectively. The loaded loading member is firmly packed into the ring plate so that there are no recesses on the outer circumferential surface of the ring plate. When the cylinder is activated, the proximity sensor detects the upper or lower non-detection hole of the ring plate. When this occurs, the detection signal is input to the controller. In addition, the above proximity sensor A wiper cylindrical body is fitted onto the outer periphery of the ring plate, and the tip edge of the wiper cylindrical body is attached to the outer periphery of the ring plate. The distance between the front surface of the proximity sensor and the outer peripheral surface of the ring plate is different. I sealed it to prevent anything from getting into it. Also, communicates the proximity sensor and the controller. When the harness becomes de-energized, the de-energized signal is input to the controller. This allows the controller to output an alarm generation command signal to the alarm device. It was configured as follows.

[0005]

【Example】

Figure 1 shows a hydraulic excavator 2' equipped with the cylinder end position detection device of the present invention. It is a figure showing circuit 11 for bucket cylinder (9) control. In the figure, the prior art Components that use the same components are given the same reference numerals. 2' is a hydraulic excavator, 3' is the work attachment, 6' is the arm, 7' is the idler link, and 12 is the arm. The proximity sensor 13 is installed near the tip of the excavator 6', and the controller 13 is installed on the hydraulic excavator 2'. 14 is an alarm; 15 communicates between the proximity sensor 12 and the controller 13; The harness 16 is a harness for connecting a plurality of connectors disposed in the middle of the harness 15. 1 connector, 17 is the hydraulic remote control valve for the bucket cylinder, 18 is the bucket cylinder Pilot switching valve for cylinder, 19 is main pump, 20 is pilot pump , 21 and 22 are relief valves, 23 is an opening/closing electromagnetic switching valve, and 24 and 25 are relief valves. The pressure oil supply and discharge pipe 26 is an oil tank. Figure 2 is a partial cutaway of part A in Figure 1. FIG. In the figure, 27 is a side plate at the tip of the arm 6', and 28 is a proximity plate. 29 is the base end of the idler link 7', 30 is the idler link 7' A pin that pivotally supports the base end portion 29. 0 is the axis of the pin 30, and 31 is the base end portion 29. The ring plates 32a and 32b fixed on the inner surface are the outer periphery of the ring plate 31, respectively. 33a and 33b are loading members, respectively. When the bucket cylinder 9 in Fig. 1 is contracted and reaches the cylinder end position, The angular position of the idler link 7', (b) is when the bucket cylinder 9 is extended and the cylinder This is the angular position of the idler link 7' when the idler link 7' reaches the idle position. In addition, the proximity sensor 12 is attached to the side plate 27 of the arm 6'. It is attached to the outside surface.

[0006] Next, FIG. 3 is a partially cutaway plan view of the main part seen from the direction BB in FIG. 2. Figure 4 is , the tip of the arm 6' with the idler link 7' removed in Fig. 3 from C. FIG. FIG. 5 is a side view of the idler link 7' seen from D-D in FIG. It is. FIG. 6 is a detailed view of section E in FIG. 3. In the figure, 34 is an idler link 7' is the bush that is fitted, and 35 is the bush that is fitted to the boss of arm 6'. It is FIG. 7 is a sectional view taken along line FF in FIG. 6. In the figure, 36 is a non- A wiper cylinder 37 made of metal is fixed to the proximity sensor mounting bracket 28 and is attached to the ring plate 31. A wiper plate for removing mud etc. attached to the outer circumferential surface, K is the front side of the proximity sensor 12 and the rear. This is the distance from the outer peripheral surface of the holding plate 31. FIG. 8 is a sectional view taken along line GG in FIG. . FIG. 9 is a diagram seen from the HH direction in FIG. 8.

[0007] Next, the configuration of the cylinder end position detection device of the present invention will be described with reference to FIGS. 1 to 9. Ru. The cylinder end position detection device of the present invention has an arm at the tip of the arm 6'. Install the proximity sensor 12 near the idler link mounting part of the side plate 27 using the proximity sensor mounting bracket. 28, and on the other hand, an external A ring plate 31 having a cylindrical circumferential surface is fixed and attached, and the outer circumferential surface of the ring plate 31 is The proximity sensor 12 is configured to detect when the idler link swings, and the bucket system is Move the cylinder 9 to a predetermined position slightly in front of the telescopic stroke end (not shown). A ring in which the proximity sensor 12 and the outer circumferential surface of the ring plate 31 face each other when the ring plate 31 is activated An upper limit non-detection hole 32a and a lower limit non-detection hole 32b are formed on the outer periphery of the plate 31, respectively. , the upper and lower non-detection holes 32a and 32b are made non-dielectric or non-magnetic, respectively. The loading members 33a and 33b made of resin material, etc., are firmly fixed to the ring plate 31. It is formed so that there is no recess on the outer peripheral surface, and when the bucket cylinder 9 is operated, the proximity sensor 1 2 detects the upper limit non-detection hole 32a or the lower limit non-detection hole 32b of the ring plate 31. The detection signal is input to the controller 13. In addition, the proximity sensor 1 A wiper cylinder 36 is fitted onto the outer periphery of the wiper cylinder 36, and the tip edge of the wiper cylinder 36 is a ring plate. 31 so that the front surface of the proximity sensor 12 and the outside of the ring plate 31 are connected to each other. The gap K between the ring and the surrounding surface was sealed to prevent dirt and other foreign matter from entering. Also, the proximity sensor When the harness 15 that connects the sensor 12 and the controller 13 becomes de-energized. By inputting the de-energization signal to the controller 13, the controller 13 The configuration is such that an alarm generation command signal is outputted to the alarm device 14 from the alarm device 14.

[0008] Next, the operation of the cylinder end position detection device of the present invention will be described. bucket Idler link 7' when the cylinder 9 is retracted and reaches the cylinder end position When the angular position is at the A position as shown in Fig. 2, the proximity sensor 12 and the lower limit non-detection Since the holes 32b face each other, the proximity sensor 12 outputs the detection signal and the controller 13. Next, extend the bucket cylinder 9 and When reaching the end position, the idler link 7' rotates around the axis 0 of the pin 30. It swings by an angle α from the A position to the B position. On the other hand, the outer periphery of the ring plate 31 has an upper The limit non-detection hole 32a is centered on the axis 0 of the pin 30 and forms an angle with the lower limit non-detection hole 32b. A hole is bored in the outer circumferential portion of the ring plate 31 at a position α. Idler link 7' and lin Since the gating plate 31 is integrally fixed, the cylinder erected when the bucket cylinder is extended. In this case as well, the proximity sensor 12 can detect the position of the hand. In the above When the detection signal when the bucket cylinder 9 expands and contracts is input to the controller 13, the control The controller 13 makes the determination and outputs a signal to the solenoid 38 in FIG. Open The closing solenoid switching valve 23 switches to the shutoff oil path position N, so the bucket cylinder 9 is It can be stopped at the cylinder end position. If you perform crushing work in this condition, the bucket will When an overload is applied to the cylinder 9 in either the expansion or contraction direction, the relief valve 2 1, the buffering effect of the bucket cylinder 9 can be exerted.

[0009] In addition, in the present invention, upper and lower non-detection holes 32a are provided on the outer periphery of the ring plate 31. and 32b, and fix filling members 33a and 33b such as resin into both holes, respectively. The outer peripheral surface of the ring plate 31 is formed so that there is no recess, and the proximity sensor 1 A wiper cylinder 36 is fitted onto the outer periphery of the wiper cylinder 36, and the tip edge of the wiper cylinder 36 is a ring plate. 31 so that the front surface of the proximity sensor 12 and the outside of the ring plate 31 are connected to each other. The gap K between the ring and the surrounding surface was sealed to prevent dirt and other foreign matter from entering. Therefore proximity The sensor 12 is capable of accurate detection and also prevents damage to the proximity sensor 12. I can do that.

0010 In addition, the harness 15 that communicates the proximity sensor 12 and the controller 13 is not energized. By inputting the de-energization signal to the controller 13 when the state is reached, An alarm generation command signal is output from the controller 13 to the alarm device 14. Ta. Therefore, the harness 15 may be disconnected or the connector 16 may not be fully connected. The safety of this device is improved because it can be recognized by an alarm when a power outage accident occurs. , reliability, and maintainability can be ensured.

[0011]

[Effect of the idea]

In the cylinder end position detection device of this invention, the proximity sensor is mounted on the side plate at the end of the arm. The resin material is loaded onto the ring plate fixed to the base end of the idler link. By attaching the parts, we were able to create a compact structure. and work When working with a crusher attached to a This prevents the bucket cylinder or other work Damage to each part of the patch can be prevented. It also fits on the outer periphery of the proximity sensor. Then, the tip edge of the wiper cylinder was brought into contact with the outer peripheral surface of the ring plate, which has no recess. Therefore, foreign matter does not enter the space between the front surface of the proximity sensor and the outer peripheral surface of the ring plate. death Therefore, the proximity sensor can perform accurate detection and prevent damage to the proximity sensor. can be done. Also, the harness connecting the proximity sensor and controller is disconnected. or when a power outage accident occurs where the connection in the harness is not complete. The safety, reliability, and maintainability of this equipment can be confirmed by alarms. can be secured.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a hydraulic excavator equipped with a cylinder end position detection device of the present invention and a bucket cylinder control circuit.

FIG. 2 is a partially cutaway detailed view of section A in FIG. 1;

FIG. 3 is a partially cutaway plan view of essential parts as seen from the direction BB in FIG. 2;

FIG. 4 is a view of the tip of the arm in a state where the idler link in FIG. 3 is removed, viewed from C.

FIG. 5 is a side view of the idler link taken along line DD in FIG. 3;

FIG. 6 is a detailed view of section E in FIG. 3;

FIG. 7 is a sectional view taken along line FF in FIG. 6;

8 is a sectional view taken along line GG in FIG. 7. FIG.

9 is a diagram seen from the direction HH in FIG. 8. FIG.

FIG. 10 is a side view of a hydraulic excavator for demolition of structures equipped with a crusher.

[Explanation of symbols]

1 Shredder 3,3’ work attachment 6,6’ arm 7,7’ Idler link 9 Bucket cylinder 12 Proximity sensor 13 Controller 14 Alarm 15 Harness 27 Side plate 31 Ring plate 32a Upper limit non-detection hole 32b Lower limit non-detection hole 33a, 33b loading member 36 Wiper cylinder

Claims (3)

[Scope of utility model registration request] Claim 1: A work attachment is attached to the front part of a construction machine, a crusher is attached to the tip of an arm of the work attachment, the crusher is rotatable in the front and back direction by the expansion and contraction operation of a bucket cylinder, and the bucket This cylinder end position detection device is capable of detecting the required cylinder end position slightly before the end of each cylinder's extension/contraction stroke, and includes a proximity sensor fixed near the idler link attachment part of the arm side plate at the end of the arm. On the other hand, a ring plate with a cylindrical outer surface is fixedly attached to the inner surface of the base end of the idler link,
The outer peripheral surface of the ring plate can be detected by the proximity sensor when the idler link swings, and when the bucket cylinder is operated to a predetermined position slightly before the end of the telescopic stroke, the proximity sensor and the outer peripheral surface of the ring plate are relative to each other. An upper non-sensing hole and a lower non-sensing hole are formed on the outer periphery of the ring plate, respectively, and a non-dielectric or non-magnetic loading member is firmly inserted into the upper and lower non-sensing holes respectively. is formed so that there is no recess on the outer circumferential surface of the ring plate, and when the proximity sensor detects the upper limit or lower limit non-detection hole of the ring plate during operation of the bucket cylinder, the detection signal is input to the controller. Cylinder end position detection device. Claim 2: Utility Model Registration Claims: In the cylinder end position detection device according to claim 1, a wiper cylinder is fitted onto the outer circumference of the proximity sensor, and the tip edge of the wiper cylinder is attached to the outer circumference of the ring plate. What is claimed is: 1. A cylinder end position detecting device, characterized in that the distance between the front surface of the proximity sensor and the outer circumferential surface of the ring plate is sealed to prevent foreign matter from entering. 3. A work attachment is attached to the front part of the construction machine, a crusher is attached to the tip of the arm of the work attachment, the crusher is rotatable in the front and back direction by the expansion and contraction operation of a bucket cylinder, and the bucket This cylinder end position detection device is capable of detecting a required cylinder end position slightly before the cylinder's extension/contraction stroke end, and is capable of detecting the cylinder end position when the harness connecting the proximity sensor and the controller becomes de-energized. A cylinder end position detection device characterized in that the controller outputs an alarm generation command signal to an alarm device when an energization signal is input to the controller.