Chainsaw apparatus having lubricating system

Abstract

A chainsaw apparatus has a guide bar, a drive sprocket, and endless cutting chain mounted over the guide bar and over the drive sprocket, a first motor drivingly connected to the drive sprocket so as to cause the drive spot sprocket to move the endless chain over the guide bar, the first control device for controlling operation of the first motor and configured to deliver at least one first data representative of an operation of the motor, a storage tank suitable adapted to receive a lubricating fluid therein, a pump cooperative with the storage tank so as to deliver the lubricating fluid toward the guide bar and the endless cutting chain, a second motor drivingly connected to the pump, and a second control device for controlling operation of the second motor on the basis of a lubricating control parameter derived from the first data. The second motor is an electric motor.

Claims

1. A chainsaw apparatus comprising: a guide bar; a drive sprocket; an endless cutting chain mounted over said guide bar and said drive sprocket; a first motor drivingly connected to said drive sprocket so as to cause said drive sprocket to move said endless chain over said guide bar; a first control device for controlling operation of said first motor, said control device being configured to deliver at least one first data representative of an operation of said first motor; a storage tank adapted to receive a lubricating fluid therein; a pump cooperative with said storage tank so as to deliver the lubricating fluid toward said guide bar and said endless cutting chain; a second motor drivingly connected to said pump, said second motor being an electric motor; and a second control device for controlling operation of said second motor by a lubricating control parameter derived from the at least one first data, the at least one data being provided by said first control device, wherein said first motor is an electric motor, wherein the at least one data is a data function of an electric current consumed by said first motor and a data function of a torque of said first motor during operation of the chainsaw apparatus.

2. The chainsaw apparatus of claim 1, further comprising: at least one sensor selected from the group consisting of a temperature sensor, a flow sensor and a level sensor, the temperature sensor delivering at least one second data representative of a temperature of said guide bar, the flow sensor delivering a flow rate of the lubricating fluid, the level sensor delivering a data representative of a lubricating fluid level in said storage tank, the lubricating control parameter being derived further from said second data, the at least one sensor being connected to said second control device so as to deliver the at least one second data to said second control device, said second control device controlling an operation of said second motor as a function of the at least one second data.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) The invention will be better understood when reading the description below, provided solely as an example and with reference being made to the attached drawings.

(2) FIG. 1 is a perspective view of a pole-mounted chain saw to which the invention can be applied.

(3) FIG. 2 is a perspective view with a break-away portion, showing the chain saw equipped with the lubricating device for its cutting elements.

(4) FIG. 3 is a block diagram of the lubricating device of FIG. 2 and an appertaining electric circuit.

DETAILED DESCRIPTION OF THE INVENTION

(5) Reference to the drawings is made to describe an advantageous, although by no means limiting, example of production of the chain saw and the method of implementation of its lubricating system according to the invention.

(6) A pole-mounted chain saw 1 is described hereafter but it is emphasized that the invention is also applicable to hand-held chain saws of all types (with a single handle, a raised handle etc.) intended for all kinds of work (pruning, forestry, sawing of various materials . . . )

(7) FIG. 1 shows a pole-mounted chain saw which has a control handle 2 mounted at the lower end of a tubular pole 3, at the upper portion of which is mounted, in a free-turning manner, a cutting head 4.

(8) The cutting head 4 includes an endless cutting chain 5 mounted at the periphery of a guide bar 6 and a drive sprocket 9. The drive of this cutting chain 5, via the drive sprocket 9, is powered by an electric motor located inside a housing 7 in FIG. 1 and referenced by the number 8 in FIG. 3. One does not exclude the realization of this drive by means of a combustion engine.

(9) As one can see in FIG. 2 in which the pole 3 is partially shown, a lubricating device of the cutting system (guide bar 6, chain 5 and drive sprocket 9) is mounted at the lower end of the pole 3, at the handle 2. This lubricating device designated in its entirety by the reference number 10 includes a storage tank 11 which is intended for containing a quantity of lubricating fluid such as oil and which communicates with a supply duct 12 to deliver this fluid to the cutting head 4. On this duct 12, a pump 13 is connected for the delivery of the lubricating fluid to the cutting head.

(10) According to a first characteristic arrangement of the invention, the pump 13 is coupled to an electric drive motor 13a, which is independent from the drive motor 8 of the cutting chain 5 of the cutting device 5-6 and is an integral part of the tool.

(11) Advantageously, the electric pump 13 is a positive displacement pump capable of delivering the lubricating fluid intermittently, in the form of successive doses, to the cutting head 4. Preferably, it is a peristaltic pump, which has the advantage of being simple, sturdy and reliable. However, the electric pump 13 delivering the lubricating fluid may be constituted by any other type of appropriate pump, such as a diaphragm pump, or a plunger pump, or a vane pump, or a gear pump.

(12) The tank 11, the pump 13 and its electric drive motor 13a are accommodated in the housing delimiting the handle 2, from which exits the aspiration section 12a of the duct 12. The lift section 12b of this duct 12, preferably constituted by a flexible pipe, then advances inside the pole 3. In a manner known as such, it extends into the guide bar 6 in the form of a distribution hole made in the latter and coming out under the chain 5.

(13) According to another important characteristic arrangement, the electric drive motor 13a of the pump 13 is controlled by an appropriately configured electronic card 20, and the chain saw features at least one sensor to be able to transmit, to said electronic card, information relative to at least one parameter or operating factor of said chain saw.

(14) Reference is now made to the block diagram of FIG. 3 to describe more completely the lubrication system and method according to the invention.

(15) Preferably, the drive motor 8 of the cutting chain 5 is constituted by an electric motor, and this electric motor is likewise controlled by an electronic card 15.

(16) A single storage battery 14 of electric energy, preferably constituted by a portable battery, can supply both the motor 13a of the electric pump 13 as well as the electric drive motor 8 of the cutting device 5-6.

(17) The electronic control card 20 of the electric pump receives data concerning the electric current consumed by the electric drive motor 8 of the cutting chain, and/or relating to the torque of said motor 8, via the electronic control card 15 of the latter, during operation of the chain saw.

(18) The electronic control card 20 of electric motor 13a of pump 13 receives and processes data sent from one or several sensors. For instance, the chain saw is equipped with: a sensor 17 capable of transmitting, to the electronic control card 20, data concerning the temperature of the guide bar 6; and/or a sensor 16 capable of transmitting, to said electronic control card 20, data relative to the rate of flow of the lubricating fluid, toward the cutting device 5-6; and a sensor 21 capable of transmitting, to said electronic card 20, data concerning the level of lubricating fluid contained in the tank 11.

(19) The electronic control card 20 of the electric motor 13a of pump 13 may be configured to control the variable speed drive of said pump, on the basis of at least one parameter derived from the data relative to the electric current consumed by the drive motor 8 of the chain saw, to the torque of this motor, and/or derived from the temperature sensor 17, or from the oil flow rate sensor 16, or from the lubrication level sensor 21.

(20) The electronic control card 20 of the electric motor 13a of pump 13 is advantageously configured to command intermittent operation of this pump in order to transmit doses or quantities of lubricating fluid, to the cutting system 5-6.

(21) The electronic control card 20 is configured so that the delivery of successive doses of lubricating fluid is spaced at a substantially constant rate and so that the quantities of lubricating fluid are based on at least one of the aforementioned parameters or operating factors.

(22) The drive pump 13 of the lubricating fluid is constituted by a positive displacement pump, for instance a peristaltic pump, or a diaphragm pump, or a plunger pump, or a vane pump, or gear pump.

(23) Preferably, and as indicated above, the chain saw features sensor 21 capable of detecting an insufficient level of lubricating fluid in the tank 11. The insufficiencies of the oil flow or level, observed by the sensors result in the trigger, via the electronic control card 20, a visual or acoustic signal 19.

(24) In the application of the invention to pole-mounted chain saws (FIGS. 1 and 2), according to which a saw head 4, comprising the various elements of the cutting device 5-6 and of their drive system 8, is mounted at the high end of a pole 3 the lower end of which is equipped with a control handle 2, the storage tank 11 of the lubricating fluid and the electric motor 13a of pump 13 for distributing this lubricating fluid, are installed near the handle 2. A duct 12 for transporting the lubricating fluid connects the storage tank 11 to the cutting device 5-6 via said pump, this duct 11 being preferably housed in the pole 3.

(25) In this application, the electronic control card 20 of the electric motor 13a of pump 13 may be installed near the handle 2, whereas the electronic control card 15 of the drive motor 8 of the cutting chain 5 may be positioned near the cutting head 4.

(26) In other applications, such as the chain saws with a simple handle or with a raised handle, the components of the electronic control cards 15 and 20 may be placed together on a single support and installed near the control handle of the tool.

(27) Advantageously, the chain saw according to the invention also features an arrangement allowing direct actuation of the electric pump 13-13a from a manual control element, for example the trigger 18, that is accessible on the handle 2 of the tool, so that, preferably continuously, oil can be sent to the guide bar/cutting chain assembly 5-6, without passing through the electronic control card 20 of said electric pump 13-13a. Such forced lubrication is, for instance, used to make the oil rise from the tank 11 to the cutting head 5-6 at the first commissioning of the tool, or when the aspiration section 12a is empty, before the actuation of the motor 8, or to obtain a bleed down of the oil distribution orifice made in the guide bar 6.

(28) According to the method of the invention, the electric pump 13-13a for distributing the lubricating fluid is controlled by means of an electronic card 20 on the basis of at least one parameter or operating factor of the chain saw.

(29) According to an advantageous mode of execution, doses of lubricating fluid are sent intermittently to the cutting device 5, 6.

(30) Preferably, in this case, doses of lubricating fluid are sent, while spacing the actuations of these doses at a substantially constant rate, said doses containing quantities of lubricating fluid, which are based on said parameter or operating factor.