JP2005299857A - Automatic grease supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic grease supply device suitably used, in particular, in a hydraulically-driven machinery needing frequent supply of grease, such as a vibrating sieve mounted on the machinery with respect to a device for supplying the grease to a grease supply part of the machinery. <P>SOLUTION: This automatic grease supply device is constituted to feed the grease to a grease supply pipe 7 with a measurement distribution valve 8 by utilizing a pressure of operating oil as a driving source of the machinery. By utilizing the pressure of the operating oil, an electric circuit and a pneumatic circuit for driving the grease supply device become unnecessary, and further by utilizing the pressure of the working oil, the grease can be supplied at a frequency in accordance with operation frequency of the machinery driven by the working oil. Further the machinery can be stopped when a grease storage chamber 11a becomes empty. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a device for supplying grease to a greasing portion such as a pivotal support portion, a bearing portion, and a sliding portion of a mechanical device, and more particularly to the above-described device in a hydraulically driven mechanical device such as a construction machine.

  Grease lubrication is widely used for lubrication of pivots, bearings, sliding parts, etc., which have a relatively slow operating speed. The grease lubrication structure for the grease lubrication part has a structure with a grease nipple for each lubrication part, and a grease supply pipe that guides the grease to a plurality of grease supply parts. There are a structure with a nipple, a structure in which a grease pump of manual, pneumatic drive or electric drive is provided at the base end of a similar greasing pipe. Grease is injected into the grease nipple when necessary using a grease gun. A greasing pipe for guiding grease to a plurality of greasing sections is usually provided with a metering type distribution valve (metering distribution valve).

  The metering valve has a small metering piston in each branch path to which the branch pipe is connected. When the pressure on the grease inflow side increases, the metering piston moves by that pressure, and the amount of grease corresponding to the stroke is supplied. Each branch pipe is extruded. When the pressure on the grease inflow side is released, the measuring piston returns to a standby state. In other words, this type of distributing valve, when grease is supplied by a grease gun or a grease pump, moves the metering piston of each branch passage only once, and sends out a predetermined amount of grease to each branch pipe. After the grease is fed out, the metering piston moved by the pressure on the grease inflow side closes the branch path at the moving end, so that the grease exceeding the predetermined amount is not supplied.

  Grease has a large viscosity and remains attached to the sliding surface and rolling surface of the greasing portion, so that a general mechanical device does not require frequent lubrication. However, when grease is scattered due to vibration or rotational inertia, or when there is a risk of operation failure or seizure due to excessive grease or intrusion due to grease breakage, frequent and reliable lubrication must be performed.

For example, an excavating bucket attached to the tip of a boom of an excavator needs to supply grease to the pivot that performs the swinging motion, but does not require frequent lubrication. Even if a nipple is provided and lubrication is performed with a manual grease gun in a timely manner, there is usually no problem. However, when a bucket equipped with a vibration sieve is installed instead of a normal bucket, frequent lubrication is required for the support part of the vibration sieve and the pivotal support part of the drive device. Accidents such as burn-in occur. In addition, this type of mechanical device has a heavy load and a poor working environment, and vibration buckets are often attached and detached on site, so it is difficult to provide an automatic greasing device that uses electricity or air pressure as a drive source. . For this reason, the vibration bucket or the like has a problem that the apparatus must be stopped in the middle of work and manual greasing work with a grease gun or the like must be frequently performed.
Japanese Patent Laid-Open No. 2003-47913

  However, in reality, it is difficult to perform the greasing work by stopping the machine at regular time intervals during the work. Especially in construction work such as construction work, where the work content varies from site to site, and the work content and the time required for the work vary depending on the situation at the site, it is difficult to work according to a uniform work standard, and the operation of the equipment Since the situation is not uniform, the timing and frequency of greasing must be left to the judgment of the field worker. However, there is a contradiction that the more enthusiastic the site worker is, the easier it is to forget to stop the machine for lubrication. Prone to problems.

  The present invention has been made to solve the problem of damage due to the lack of grease such as a vibration sieve mounted on a construction machine and a problem of shortening the service life, and is particularly applicable to a hydraulically driven mechanical device that requires frequent grease supply. It is an object of the present invention to obtain a suitable automatic grease supply device.

  The present invention solves the above problem by sending grease to a greasing pipe 7 provided with a metering valve 8 by using the pressure of the hydraulic oil that is a drive source of the mechanical device. By using the pressure, there is no need to provide an electric circuit or a pneumatic circuit for driving the greasing device, and by using the pressure of the hydraulic oil, the operating frequency of the mechanical device driven by the hydraulic oil can be reduced. Lubrication is performed at a frequency corresponding to the above. Furthermore, in the present invention, when the grease in the storage chamber 11a becomes empty, it is possible to easily stop the mechanical device.

  That is, the grease automatic greasing device according to the present invention is an automatic grease greasing device for a mechanical device provided with a hydraulic circuit 1 for supplying operating pressure, and the greasing points a, b, c, A grease supply pipe 7 for guiding grease to the cylinder 11 and a cylinder 11 having one chamber 11b sandwiching the piston 12 connected to the hydraulic circuit 1 and the other chamber 11a connected to the metering valve 8 of the grease supply pipe. And an automatic grease supplying device in which the other chamber 11a of the cylinder is a grease storage chamber.

  In the above-described device, every time the pressure of the hydraulic circuit 1 for hydraulic fluid increases, that is, every time the mechanical device driven by the hydraulic fluid is operated, a pivotal support portion, a bearing portion, and a sliding portion provided in the mechanical device. Grease is supplied to locations a, b, and c that require lubrication, such as the part. While the mechanical device is continuously operated, that is, while the pressure of the hydraulic circuit 1 is rising, the branch pipes 9a, 9b,. Since the branch path is closed, only a predetermined amount of grease is supplied to each grease supply unit.

  Each time lubrication is performed, the piston 12 moves by an amount corresponding to the amount of grease required for one lubrication. When the operation stop of the mechanical device is repeated, the lubrication is repeated accordingly, and the piston 12 moves sequentially. When the grease in the storage chamber 11a is consumed, the piston 12 reaches the stroke end (the extended end when the cylinder rod side chamber is used as the storage chamber, and the degenerated end when the head side chamber is used as the storage chamber), and then the grease is supplied. Will not be performed.

  The invention of claim 2 of the present application is an automatic greasing apparatus having the above-described configuration, wherein the hydraulic circuit 1 communicates with the hydraulic oil tank 6 when the piston 12 reaches the stroke end on the storage chamber 11a side. The valve 14 is provided.

  According to the structure of the second aspect, when the grease is consumed and the piston 12 reaches the stroke end, the pressure of the hydraulic circuit 1 is released and the mechanical device is not driven. Therefore, it is possible to prevent the machine device from being operated in a state where grease is not supplied.

  According to a third aspect of the present invention, in the automatic greasing apparatus according to the second aspect, the piston 12 includes a piston rod 13, the pressure release valve 14 is a spring return type normally closed switching valve, The piston rod is mechanically connected to the valve rod 15 of the switching valve.

  In addition to the structure according to claim 3, as another preferable structure, when the piston rod 13 reaches the stroke end, the pilot valve is mechanically operated by the rod, and the pressure is released by the pilot pressure generated thereby. A structure for opening the valve 14 can be exemplified. A structure is also possible in which the limit switch is operated at the stroke end of the piston rod 13 and the solenoid valve is operated by the electrical signal to release the pressure of the hydraulic circuit 1, but an electric circuit is required in addition to the hydraulic circuit 1. It is disadvantageous.

  According to the present invention described above, it is possible to automatically supply grease to a required location at a required timing without using an electrically driven or pneumatically driven grease pump. That is, since the lubrication is performed every time the operation of the mechanical device to be lubricated is stopped, the number of times of greasing increases when the operation is frequently stopped, and the number of times of greasing decreases when the number of operations is decreased.

  Since hydraulic pressure for operating the vibration sieve is naturally supplied to an attachment such as a bucket with a vibration sieve attached to the tip of a boom of a power shovel, for example, a hydraulic circuit 1 is provided. If it is connected to the cylinder 11 for storing grease, the grease is automatically supplied, so that no electrical wiring is required for control, and it is particularly suitable for mechanical devices that are operated in harsh environments and may fail. Less is.

  Further, according to the structures of claims 2 and 3, it is possible to easily stop the operation of the mechanical device when the grease in the storage chamber 11a is consumed, and it is possible to more reliably damage the mechanical device due to the lack of grease. Can be prevented.

  FIG. 1 and FIG. 2 are diagrams schematically showing an embodiment of the present invention. FIG. 1 shows a machine stop state when grease is present in the storage chamber, and FIG. 2 shows a machine when grease is consumed. Indicates the operating state.

  In the figure, 1 is a hydraulic circuit of hydraulic fluid that drives the mechanical device, 2 is a return circuit of the hydraulic fluid, 3 is a hydraulic pump, 4 is an operation valve that stops the operation of the target mechanical device 5, and 6 is This is a hydraulic oil tank. Strainers and relief valves generally provided in the hydraulic circuit are not shown in the figure. 7 is a grease supply pipe, 8 is a metering distribution valve, 9a, 9b... Are branch pipes branched from the metering valve 8, and a, b. 5 is a mechanical device (for example, a vibration sieve device). In the illustrated example, a, b, and c are oil supply locations in the mechanical device 5, and d and e are oil supply locations outside the mechanical device. is there. Reference numeral 10 denotes a hydraulic actuator (for example, a hydraulically driven vibrator) that drives the mechanical device 5.

  A pressure release valve 14 is interposed in the hydraulic circuit 1. The illustrated pressure release valve 14 is a spring return type switching valve. The hydraulic circuit 1 passes between the normally open ports 14 a to 14 c, and the normally closed port 14 b is connected to the return circuit 2. The hydraulic circuit 1 after passing through the pressure release valve 14 is connected to the hydraulic actuator 10 and is connected to the head side chamber 11b of the cylinder 11 through the branch pipe 1a.

  The tip of the piston rod 13 connected to the piston 12 of the cylinder 11 and the tip of the valve rod 15 of the release valve 14 are connected by a seesaw link 17 that swings around a fulcrum 16. Long holes 18 and 19 are provided in the connecting portions of the rods 13 and 15 and the link 17 so that the linear movement of the rods 13 and 15 and the arc movement of the link 17 are smoothly transmitted. The cylinder 11 and the release valve 14 are mounted in such a positional relationship that the inflow port 14a and the normally closed port 14b communicate with each other when the piston 12 of the cylinder reaches the rod end. The rod side chamber 11 a of the cylinder 11 is connected to the inlet of the metering valve 8 by an inflow pipe 20. The inflow pipe 20 is provided with a grease nipple 21 with a check valve.

  The rod side chamber 11a of the cylinder is a grease storage chamber, and grease is supplied from the grease nipple 21 with a grease gun and stored therein. This grease storage operation is performed, for example, at the start of a machine inspection. By supplying the grease to the storage chamber 11a, the piston 12 moves to the stroke end on the head end side.

  When the operation valve 4 is switched from this initial state and the hydraulic pressure of the hydraulic circuit 1 rises, the hydraulic pressure is supplied from the branch pipe 1a to the head side chamber 11b of the cylinder 11 to pressurize the grease in the rod side chamber 11a. The pressurized grease flows through the inflow pipe 20 to the metering / distribution valve 8, and the metering / distribution valve 8 measures the inflowed grease in the branch portions of the individual branch pipes 9a, 9b. Grease the grease supply parts a, b... By a predetermined amount set by the stroke of the piston. The piston 12 of the cylinder moves to the rod end side by the total amount of grease necessary for one lubrication.

  When the operation valve 4 is switched and the hydraulic actuator 10 stops, the pressure in the hydraulic circuit 1 decreases and the grease pressure in the storage chamber 11a also decreases, so that the metering piston of the metering distribution valve 8 returns. Next, when the operation valve 4 is switched to the operation side, the grease supply parts a, b,... Are greased in the same manner, and the piston 12 moves to the rod end side by the total amount of grease to be supplied. To do. That is, every time the hydraulic actuator 10 is operated, the lubrication points a, b,... Are lubricated, and the piston 12 gradually moves toward the rod side stroke end. The valve rod 15 of the opening valve is gradually pushed toward the normally closed port 14c side.

  The cylinder 11 is set to a size that allows the storage chamber 11a to store a sufficient amount of grease necessary for work during a predetermined inspection period (for example, 1 day if daily start inspection is performed). . If grease is fully poured into the storage chamber 11a at the time of inspection, the grease will not run out during operation. If you forget to inject grease at the time of inspection and continue to operate the machine, as shown in FIG. 2, the storage chamber 11a is emptied and the piston 12 reaches the stroke end on the rod side of the cylinder and opens. Since the inflow port 14a and the normally closed port 14b of the valve 14 are communicated and the hydraulic pressure of the hydraulic circuit 1 is bypassed to the return circuit 2, the hydraulic actuator 10 is stopped, and therefore the mechanical device is in a state where grease is not injected. Is prevented from being operated, and damage to the machine due to depletion of grease is prevented.

  As can be understood from the above-described embodiments, according to the present invention, a predetermined amount of grease is supplied to a necessary portion of the mechanical device every time the hydraulically driven mechanical device is stopped. In addition, since this automatic greasing operation is performed without using a control device or an electric or pneumatic drive grease pump, it can be carried out at a low cost, and it is not necessary to provide electric wiring or pneumatic piping. It is also characterized by excellent durability.

The block diagram which shows typically one Embodiment of this invention The same figure as Fig. 1 showing the condition when grease is consumed

Explanation of symbols

1 Hydraulic circuit 6 Hydraulic tank 7 Grease supply line 8 Metering valve
11 cylinders
11a Rod side chamber
11b Head side chamber
12 piston
13 Piston rod
14 Release valve
15 Valve rod
a ~ e Lubrication part

Claims (3)

  An automatic grease supply device for a mechanical device having a hydraulic circuit (1) for supplying a working pressure, and a grease supply pipe for introducing the grease to a grease supply location (a, b, c ...) of the mechanical device ( 7) and a cylinder (11) in which one chamber (11b) sandwiching the piston (12) is connected to the hydraulic circuit, and the other chamber (11a) is connected to the metering valve (8) of the greasing pipe. And the other chamber of the cylinder is a grease storage chamber.   A pressure release valve (14) that communicates the hydraulic circuit (1) to a hydraulic oil tank (6) when the piston (12) reaches a stroke end on the storage chamber (11a) side. The automatic greasing apparatus according to 1.   The piston (12) includes a piston rod (13), the pressure release valve (14) is a spring return type normally closed switching valve, and the piston rod is mechanically connected to the valve rod (15) of the switching valve. The automatic greasing apparatus of Claim 2 connected to.

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