JPH0733620Y2 - Work equipment lifting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a lifting device for a working device including a pair of left and right lift cylinders, such as a take-up reel in a combine.

(Prior Art) Conventionally, for example, in a combine harvester, crops scraped by a scraping reel are cut by a cutting blade, and cut crops are conveyed from a platform auger to a handling room by a chain conveyor of a feeder house and are screw type. It is designed to be threshed by a handling cylinder or rotor. Such a combine reel can be moved up and down via a lifting arm by a pair of left and right reel lift cylinders mounted on the platform.

One of the pair of left and right lift cylinders is a double-acting type, the other is a single-acting type, and the uppermost position side of the double-acting cylinder and the lowermost position side of the single-acting cylinder are communicated with each other by a communication pipe. I proposed this as a Japanese patent application No. Sho 60-49052.

(Problems to be solved by the invention) According to the lifting device as described above, the single-acting cylinder side may be lifted up due to the rough field in the field during the cutting operation, and the divider and the reel may come into contact with each other. Either the divider or the reel is damaged because the cylinder has no damper effect.

In the lifting device of the working machine of this type, a malfunction often occurs unless the damper function is provided.

(Means for Solving the Problem) Therefore, the technical problem of the present invention is to obtain a lifting device for a working machine including a single-acting cylinder having such a damper effect. One of a pair of left and right lift cylinders to be driven is a double-acting type, the other is a single-acting type, and the uppermost position side of the double-acting cylinder and the lowermost position side of the single-acting type cylinder are connected to each other by a communication pipe. In the above, the piston of the single acting cylinder is provided with a small diameter communication hole.

(Effect of the Invention) According to this technical means, since the piston of the single-acting cylinder is provided with the communication hole, the oil supplied to the single-acting cylinder flows between the piston rod and the cylinder through the communication hole. The impact of the piston rod causes the oil to flow out to the piston surface while the passage resistance is being given in the communication hole, so the impact force is mitigated by the oil between the piston rod and the cylinder, and the work machine is moved up and down. Has the effect of not being damaged. Moreover, since one of the cylinders is a single-acting piston type, there is no buckling or falling of the rod.

(Embodiment) Hereinafter, the entire combine will be described based on an embodiment shown in the drawings.

In FIG. 6, the crop scraped by the scraping reel (1) is mowed by the cutting blade (2), and the cropped crop is scraped by the scraping auger (3), that is, the platform auger to the feeder house (4) chain conveyor. In (5), it is carried to the handling room (6) and threshed in the screw type handling room, that is, the rotary (7). The threshed ones are dropped from the crimp net (8) onto the rocking sorting disc (9) to be sorted.

Those threshed on this rocking sorting board (9) are sorted, but only the long straws are carried toward the rear dust outlet.

In addition, the items sorted by the rocking sorter (9) are sorted by the sorting wind by Kara (10), and the grains fall into the first gutter (11) and the second drop into the second gutter (12). , The grain dropped to the first gutter (11) is carried to the paddy tank via the lifting cylinder, and the second grain dropped to the second gutter is returned to the rocking sorter (9) by the second reduction auger. It has become so.

By the way, the lifting and lowering of the reel (1) in the above combine is performed by the lifting arm (12) as shown in FIG. 5, and the lifting arm (12) is supported by the left and right lifting cylinders (14) (15) of the platform. Move up and down.

By the way, the conventional cylinder is a single-acting type on both the left and right sides as shown in FIG. 2, and the communication small hole (16) for air bleeding has the right cylinder (1
5) is provided at the uppermost position side, which communicates with the lowest position side of the left cylinder (14) through the communication pipe (17), and the air vent valve (18) is located at the uppermost position side of the left cylinder (14). .

Oil is injected from the inlet (19) on the lowest position side of the right cylinder (15), flows into the left cylinder (14) through the air vent communication small hole (16) and the communication pipe (17), and the air vent valve (1
The air is removed from 8).

However, when the piston (20) of the right cylinder (15) has a full stroke, the left and right cylinders communicate with each other through the small hole (16), so that the strokes of the left and right cylinders are likely to have an error.

Also, if the load on the left and right cylinders is significantly different, the oil in the left cylinder (14) will flow into the right cylinder (15) through the small hole (16), leaving the right cylinder (15) stopped at the full stroke position. In some cases, only the left cylinder (14) contracts, resulting in an error (a) as shown in FIG.

Furthermore, the communication eyelets cannot be made large and thus bubbles as the oil passes through.

From the above, the right cylinder (15) in Japanese Utility Model Application No. 60-49052
Is a double-acting type and the left cylinder (14) is a single-acting type.

That is, oil can flow from the inlet (19) into the right cylinder (15) through the passages (22a) and (22b) to the lower side of the piston (20), and further the right cylinder (1
It is also possible to inject oil into the right cylinder (15) from the upper side of the piston (20) from the oil injection valve (24) of the oil injection pipe (23) attached to 5) and the injection port (25) on the uppermost position side of the right cylinder. ing.

Face the inlet (25) of the right cylinder (15) and connect the communication pipe (1
The starting end of 7) is opened (26) in the cylinder, and the end of it is designed to allow oil to flow into the left cylinder (14) through the opening (27). The uppermost position side of the left cylinder (14) There is a valve (18) for bleeding air.

Oil is also pumped (29) by the drive of the engine (31) from the tank (30) through the valve (32) to the pipe (33) to the pilot check (37), pipe (38) and slow return (39). Then it is sent to the inlet (19).

In addition, (36) is a relief valve, and pipe (35) is pipe (33).
Connected to. Now, to bleed air immediately after assembly, remove the reel (1) from the lifting arms (12) (12). Then, attach a weight of about 40 kg to the right lifting arm (12) and place the piston (20) in the lowest position of the cylinder.

At that time, the air vent valve (18) of the left cylinder (14) is opened so that the air in the cylinder can be vented. Next, oil is injected from the oil inlet (19) through the passages (22a) and (22b) into the right cylinder (15) while the relief is being exerted, the piston (20) is pushed up to the uppermost position, and then the oil injection valve (2
4) open. Then, the lubrication valve (2
Oil is injected into the left cylinder (14) through the communication pipe (17) from the oil supply pipe (23) through the upper side of the piston (20) of the cylinder (15) via the (4).

According to the lubrication, the piston rod (2
8) rises and oil finally comes out from the air bleeding valve (18), but when there is no air bubble in the oil, the left cylinder air bleeding valve (18) is closed, and then the right cylinder oiling valve (24) Close.

As a result, the left and right piston rods (28) (21) are aligned at the uppermost position, and the lubrication pipe (23) and the communication pipe (17)
Through this, both cylinders are sealed with a fixed volume of communicating oil.

Since this communicating oil is completely sealed, it is not affected by stroke error or load balance. At the time of air bleeding described above, since the communication port (26) between the right cylinder (14) and the communication pipe (17) is large, it is possible to suppress the generation of bubbles.

By the way, when performing the mowing work using the above-mentioned work implement lifting device, the left cylinder, that is, the single-acting cylinder has no damper effect, so the single-acting cylinder side floats up due to the rough field and the divider and reel come into contact with each other. If this happens, the divider or reel will be damaged.

Therefore, in the present invention, a small communicating hole (41) is provided in the piston (40) of the single acting cylinder (14). In this case, the rod cross-sectional areas are set equal to each other so that the reel is moved up and down horizontally, hydraulic pressure is applied to the right cylinder, that is, the return type cylinder (15), and the left and right cylinders are moved up and down in synchronization with each other.

If the single-acting cylinder is of the single-acting ram type, there is no restriction on the direction in which the rod is pulled out, and the inside of the cylinder easily becomes a negative pressure and can be pulled out.

In order to avoid the above, in the present invention, the single-acting cylinder is a piston type, and the communication hole (41) is provided in the piston (40) to provide oil passage resistance when the rod is pulled out. That is, the oil supplied from the communication pipe (17) and flowing into the cylinder (14) flows out between the piston rod (28) and the cylinder (14) through the communication hole (41), but the piston area is the communication hole (41). Since it is larger than the cross-sectional area of the piston (40), it does not prevent the piston (40) from rising. The oil that enters between the piston rod (28) and the cylinder (14) through the communication hole (41) pulls out the piston (40). At that time, the impact applied to the piston rod flows out to the surface of the piston (40) while passing resistance is given in the communication hole (41), so the impact is mitigated by the oil between the piston rod (28) and the cylinder (14). To be done.

As a result, a damper effect is given to the single-acting cylinder, and the impact between the divider and the reel is alleviated.

[Brief description of drawings]

 FIG. 1 is a structural explanatory view showing the device of the present invention. FIG. 2 is a structural explanatory view showing a conventional device. FIG. 3 is a partial view of the same as above. FIG. 4 is an explanatory view showing a stepped state of the same as above. FIG. 6 is a perspective view showing the device. FIG. 6 is an overall view of the combine. (1) …… Reel (12) …… Lifting arm (14) (15) …… Reel lift cylinder (16) …… Communication small hole for air bleeding (17) …… Communication pipe (18) …… Air bleeding valve ( 20) …… Piston (23) …… Oiling pipe (24) …… Oiling valve (40) …… Piston (41) …… Communication hole

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. One of a pair of left and right lift cylinders for raising and lowering a working machine is a double-acting type, and the other is a single-acting type. The working machine lifting device characterized in that the piston of the single-acting type cylinder has a communication hole of a small diameter, which is communicated with the lowest position side.