JPH025921Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a monitoring device for refueling the sawing chain of a portable chain saw, which is popular especially for forestry operations such as felling, delimbing, and cutting.

The saw chain of a chain saw slides at high speed in the groove on the outer periphery of the guide plate, so it easily overheats, and saw chips get stuck in the groove, increasing sliding resistance and reducing work efficiency. There are some drawbacks.

To prevent such a situation, it is essential to smoothly supply oil to the groove, and it is necessary to cool the chain and prevent sawing chips from solidifying. This creates the need to monitor the refueling status. As a countermeasure to this problem, it has been proposed to expose a part of the suction pipe of the oil pump to the outside, as disclosed in Japanese Utility Model Application Publication No. 55-83302, but this method may cause oil spills depending on the situation. may not be immediately and reliably recognized.

Therefore, the present invention aims to provide a chain saw that can issue a warning more positively and reliably.

The present invention will be explained in detail below with reference to embodiments shown in the figures.

FIG. 1 is a partially sectional external view of a chain saw according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the gist of the present invention, and shows an enlarged view of the monitoring device of FIG. 1.

The chain saw 1 according to the embodiment is a chain saw that is powered by an engine. The engine is the main body, a machine frame is provided around the machine frame via a vibration isolating member, and a front handle and a rear handle are provided to operate the machine body.

A saw chain guide plate 2 protruding forward is provided on one side of the main body. A saw chain guide groove (not shown) in the guide plate 2 maintains communication with an oil supply hole through the mounting surface of the main body crankcase, allowing oil to be supplied to the peripheral groove of the guide plate 2.

The main body (engine) is equipped with an oil pump 3 in a part of the crankcase, and holes are drilled in the necessary places in the crankcase so that the guide plate 2 can be supplied with oil, but the work on the discharge side of the pump 3 is very difficult. Have difficulty. On the other hand, the suction side of the pump 3 is usually connected to the oil tank 4 through suction passages 5 and 6 made of flexible hoses, so that the work is easy. The present invention is characterized in that the monitoring devices 7 to 16 are interposed on the suction side, and additional work to the ready-made product is possible and easy. The monitoring devices 7 to 16 on the suction side include a sensing device (sensor) that senses the negative pressure inside the suction passages 5 and 6. The outline of this circuit is shown in Figure 2. This sensor 7 has connecting ports 5' and 6' for the suction passages 5 and 6 cut in the middle on one side of a housing 10, and the inner space is horizontally and airtightly divided into two by a diaphragm 11 to form an oil chamber 10L. Air chamber 10H is provided, oil chamber 1
A pressure regulating spring 12 is arranged in the center of 0L.
The diaphragm 11 is deformed by compressing the spring 12 due to the internal negative pressure when oil is sucked into the pump 3 through the suction passages 5 and 6, but the diaphragm 11 has the effect of restoring itself due to the drag force of the spring 12. . An electrical conductor 13 is integrally provided on the air chamber 10H side of the diaphragm 11, and electrical circuit contacts 15, 15 face it.
By the deformation operation of the diaphragm 11, the diaphragm 11 comes into contact with and separates from the conductor 13 to perform a switch operation.

Next, an alarm display device 8 connected to an electric circuit 9 including a power source 16 is provided in a part of the fuselage, so that the oil distribution status can be monitored. The power source 16 may be a power source generated by the power generating device of the main body or a power source such as a dry battery, and the design is flexible.

The effects will be explained below.

When the main body is operated, the sawing chain slides around the chain guide plate 2 at high speed. Since the pump 3 also operates at the same time, the oil in the oil tank 4 is sucked in through the suction passages 5 and 6, passes through the main body crankcase portion, and is supplied to the chain guide plate 2. During this time, the sensor 7 installed in the suction passages 5 and 6 on the pump suction side senses the negative internal pressure, and the diaphragm 11 deforms inward against the spring 12. As a result, the electrical conductor 13 of the diaphragm 11
is separated from the contacts 15, 15 of the electric circuit 9, cutting off electrical conduction. As a result, the alarm display device 8 connected to the circuit 9 indicates that there is no abnormality by turning off the light bulb or the like.

During the next operation, if the oil in the oil tank 4 runs out or is completely consumed, the internal pressure in the suction passage 5 will rise close to atmospheric pressure, and the diaphragm 11 will be restored to its old state by the pushing force of the spring 12. The contacts 15, 15
Since the contact with the conductor 13 is restored, the electric circuit 9 is energized and a light or the like turns on, which is interpreted as an alarm. What to use for the display device 8 is free to design.

As described above, this invention is equipped with a diaphragm type internal pressure sensor on the suction side of the refueling circuit, so it avoids the initial refueling of the pump device becoming unsmooth, is less susceptible to changes in the attitude of the aircraft, and is able to detect slight internal pressure changes. However, it works reliably, and can be modified into existing products, making it a huge contribution to improving the functionality of products.
Furthermore, by installing such a simple monitoring device, there is no need for skill in handling the machine, and the need for careful attention to detail is eliminated, making the machine easy for anyone to use.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional external view of a chain saw according to an embodiment of the present invention. FIG. 2 is an explanatory diagram of the gist of the embodiment of the present invention. 1... Portable chain saw, 2... Saw chain guide plate, 3... Oil pump, 4... Oil tank, 5, 6
... Suction path, 7 ... Sensor, 8 ... Alarm display device, 9 ... Electric circuit.

Claims (1)

[Scope of utility model registration request] A sensor 7 for sensing the internal pressure of the suction passages 5 and 6 is arranged in the suction passages 5 and 6 between the oil pump 3 and the oil tank 4 of the automatic oil supply system passage that refuels the saw chain guide plate 2 of the portable chain saw 1. Contacts 15, 15 are connected to and separated by a diaphragm 11 which divides the inner space of the housing 10 of the sensor 7 into an oil chamber 10L and an air chamber 10H, which constitute a part of the suction passages 5, 6, and the fuselage. A chain saw is connected to an alarm display device 8 provided in a part of the chain saw through an electric circuit 9, and the alarm display device 8 can issue an alarm regarding the refueling state.