JP7123789B2 - chainsaw - Google Patents

Description

The present disclosure relates to a chain saw that includes a fixing member for fixing a guide bar to a body.

Patent Literature 1 describes a chain saw that includes a guide bar attached to a main body and a saw chain stretched over the guide bar. In the chain saw disclosed in Patent Document 1, the guide bar is fixed to the main body by pinching and tightening the guide bar between the male threaded portion projecting from the side surface of the main body and the nut screwed onto the male threaded portion. .

Japanese Patent No. 6137467

When the saw chain of the chain saw is driven, frictional heat generated between the saw chain and the guide bar is transferred to the nut via the guide bar, which may raise the temperature of the nut. .

An object of the present disclosure is to suppress an increase in temperature in a fixing member used to fix a guide bar to a main body.

One aspect of the present disclosure is a chainsaw that includes a body, a guide bar, saw chain, a fixing member, and a control circuit. The main body accommodates therein a driving source configured to generate a driving force by rotating. The guide bar is fixed to the main body so as to protrude from the main body. The saw chain is attached along the outer periphery of the guide bar and is configured to rotate along the outer periphery of the guide bar by driving force generated by the drive source. The fixing member is arranged outside the main body to fix the guide bar to the main body. The control circuit performs a stop process to stop the rotation of the drive source when a protection condition indicating that the member temperature, which is the temperature of the fixed member, is equal to or higher than a preset protection temperature is met, and a protection condition is met. reduction processing for reducing the rotation of the driving source more than in the case where there is no drive source.

The chain saw of the present disclosure configured in this way can stop the rotation of the drive source or reduce the rotation of the drive source when the temperature of the fixed member rises above the protection temperature. Therefore, the chain saw of the present disclosure can suppress the temperature rise of the fixing member due to frictional heat generated between the saw chain and the guide bar.

Further, in one aspect of the present disclosure, the control circuit includes a temperature estimator configured to estimate the member temperature based on the rotation speed of the drive source, and the protection condition is the temperature of the member estimated by the temperature estimator. The temperature may be equal to or higher than the protection temperature. In this way, the chain saw of the present disclosure can suppress the temperature rise of the fixed member without providing a temperature sensor that directly detects the member temperature, thereby simplifying the configuration of the chain saw. can.

Further, in one aspect of the present disclosure, the control circuit includes a heat generation amount estimation unit configured to estimate a member heat generation amount, which is a heat generation amount of the fixed member, based on the rotation speed of the drive source, and the protection condition is Alternatively, the member heat generation amount estimated by the heat generation amount estimating unit may be equal to or greater than a preset protection heat generation amount. In this way, the chain saw of the present disclosure can suppress the temperature rise of the fixed member without providing a temperature sensor that directly detects the member temperature, thereby simplifying the configuration of the chain saw. can.

Further, in one aspect of the present disclosure, the control circuit includes a load determination unit configured to determine whether the load state or the no-load state, and the protection condition is the no-load state and the drive source The no-load drive time during which the motor is driven may be longer than or equal to a preset no-load protection time. A load state is a state in which a worker has started work. A no-load state is a state in which the worker is not working. In this way, the chain saw of the present disclosure can suppress the temperature rise of the fixed member without providing a temperature sensor that directly detects the member temperature, thereby simplifying the configuration of the chain saw. can.

In one aspect of the present disclosure, the control circuit includes a time measurement unit, and the protection condition is that the operation time measured by the time measurement unit is equal to or longer than a preset operation protection time. good too. The time measurement unit is configured to measure the operation time during which the driving operation unit operated by the user is operated to generate the driving force in the driving source. In this way, the chain saw of the present disclosure can suppress the temperature rise of the fixed member without providing a temperature sensor that directly detects the member temperature, thereby simplifying the configuration of the chain saw. can.

Further, in one aspect of the present disclosure, the temperature detection unit configured to detect the temperature of the member is provided, and the protection condition is that the temperature of the member detected by the temperature detection unit is higher than the protection temperature. good. As described above, the chain saw of the present disclosure includes the temperature detection unit that directly detects the member temperature, so it can be accurately determined whether or not the protection condition is satisfied.

In one aspect of the present disclosure, the control circuit includes a level detection unit, and the temperature estimation unit estimates the member temperature according to the tension level so that the higher the tension of the saw chain, the higher the member temperature. You may do so. The level detector is configured to detect a tension level indicating the tension of the saw chain relative to the guide bar. With this, the chain saw of the present disclosure can estimate the member temperature using the tension level, so it can accurately determine whether or not the protection condition is satisfied.

Further, in one aspect of the present disclosure, the control circuit includes a level detection unit, and the heat generation amount estimation unit calculates the member heat generation amount according to the tension level so that the higher the tension of the saw chain, the higher the member heat generation amount. may be estimated. The level detector is configured to detect a tension level indicating the tension of the saw chain relative to the guide bar. With this, the chain saw of the present disclosure can estimate the amount of heat generated by the member using the tension level, so it can accurately determine whether or not the protection condition is satisfied.

Further, in one aspect of the present disclosure, when the member temperature estimated by the member temperature estimating unit exceeds a preset temperature retention determination value, power supply to the control circuit is maintained. A temperature dependent holding section may be provided. Thereby, the chain saw of the present disclosure can store the estimated member temperature until the estimated member temperature becomes equal to or lower than the temperature retention determination value. Therefore, in the chain saw of the present disclosure, even if the operator stops driving the chain saw while the member temperature exceeds the temperature holding determination value and immediately resumes driving the chain saw, the member It is possible to prevent the temperature from being set to the initial value. This allows the chainsaw of the present disclosure to resume estimating the member temperature based on the stored member temperature.

Further, in one aspect of the present disclosure, when the member heat generation amount estimated by the heat generation amount estimation unit exceeds a preset heat generation amount retention determination value, power supply to the control circuit is maintained. may be provided with a calorific value dependent holding unit configured as follows. Thereby, the chain saw of the present disclosure can store the estimated member heat generation amount until the estimated member heat generation amount becomes equal to or less than the heat generation amount holding determination value. Therefore, in the chain saw of the present disclosure, even if the operator stops driving the chain saw in a state where the heat generation amount of the member exceeds the heat generation holding determination value, and immediately after that, the driving of the chain saw is restarted. , the member heating value can be prevented from being set to the initial value. This allows the chain saw of the present disclosure to resume estimating the member heating value based on the stored member heating value.

It is a perspective view showing the whole chain saw composition. 1 is a block diagram showing an electrical configuration of a chain saw; FIG. 4 is a flowchart showing motor control processing of the first embodiment; 4 is a flowchart showing temperature protection determination processing of the first embodiment; 4 is a flowchart showing initial temperature calculation processing; 9 is a flowchart showing motor control processing according to the second embodiment; It is a flow chart which shows temperature protection judgment processing of a 2nd embodiment. It is a flow chart which shows temperature protection judging processing of a 3rd embodiment. It is a flow chart which shows temperature protection judging processing of a 4th embodiment. FIG. 14 is a flowchart showing temperature protection determination processing according to the fifth embodiment; FIG. FIG. 14 is a flowchart showing temperature protection determination processing of the sixth embodiment; FIG. FIG. 12 is a flowchart showing temperature protection determination processing of the seventh embodiment; FIG. FIG. 21 is a flowchart showing temperature protection determination processing of the eighth embodiment; FIG. FIG. 22 is a flowchart showing tension level setting processing of the eighth embodiment; FIG. FIG. 22 is a flowchart showing tension level setting processing of the ninth embodiment; FIG. FIG. 22 is a flowchart showing temperature protection determination processing of the tenth embodiment; FIG. FIG. 22 is a flow chart showing a power holding process of the eleventh embodiment; FIG. FIG. 22 is a flow chart showing a power holding process of the twelfth embodiment; FIG. FIG. 22 is a flowchart showing temperature protection determination processing of the thirteenth embodiment; FIG. FIG. 16 is a flow chart showing temperature protection determination processing of the fourteenth embodiment; FIG. FIG. 16 is a flow chart showing temperature protection determination processing of the fifteenth embodiment; FIG. FIG. 22 is a flowchart showing temperature protection determination processing of the sixteenth embodiment; FIG.

(First embodiment)
A first embodiment of the present disclosure will be described below with reference to the drawings.
As shown in FIG. 1, the chain saw 1 of the present embodiment is a type of hand-held electric power tool. 5.

A bolt 6 fixed to the guide bar 4 is inserted into a through hole (not shown) formed in the main body 5 so as to protrude from the inside to the outside of the main body 5 . The guide bar 4 is fixed to the main body 5 by screwing the bolt 6 into the nut 7 outside the main body 5 . Therefore, the nut 7 is exposed on the outside of the main body 5 so as to be accessible to the user of the chain saw 1 .

The guide bar 4 is a member for rotatably supporting the saw chain 3 together with a sprocket (not shown) provided inside the main body 5 . A motor 10 shown in FIG. 2 is accommodated in the main body 5 . The motor 10 drives the saw chain 3 to move along the outer periphery of the guide bar 4 by rotating a sprocket (not shown).

As shown in FIG. 1, the main body 5 is provided with a first grip 12 and a second grip 14 to be gripped by the left and right hands of the user, respectively.
The first grip 12 has a space for gripping the chain saw 1 above the main body 5 from the front to the rear of the main body 5 when the direction in which the guide bar 4 protrudes from the main body 5 is defined as the front. It is bridged so as to form between them.

The second grip 14 has one end connected to the front side wall of the first grip 12 and the other end connected to the rear end side wall of the main body 5 .
Therefore, the user can hold the first grip 12 above the main body 5 and the second grip 14 on the side of the main body 5 .

A hand guard 16 connected to an emergency stop mechanism of the motor 10 is provided in front of the first grip 12 . A battery pack 8 is detachably attached to the lower end portion at the rear of the main body 5 .

A drive switch 18 that can be pulled by the user's hand holding the first grip 12 is provided on the lower side of the first grip 12 . The drive switch 18 is a trigger switch that is turned on when pulled by the user.

A lock release lever 19 is provided on the upper side of the first grip 12 . When the user pushes down the lock release lever 19, the engagement between the lock release lever 19 and the drive switch 18 is released, and the drive switch 18 becomes operable. Therefore, the user can operate the drive switch 18 with a fingertip by holding the first grip 12 while pressing the lock release lever 19 from above. On the other hand, the user cannot operate the drive switch 18 unless the lock release lever 19 is pushed down.

An operation panel 20 is provided above the first grip 12 . A main power switch 21 and a state display section 22 for displaying the operating state of the chain saw 1 are assembled to the operation panel 20 .

The main power switch 21 is a tact switch that is turned on only when the user is pushing it down. The status display section 22 is composed of two LEDs with different lighting colors. The state display unit 22 displays the operation mode for controlling the motor 10 in a identifiable manner by switching the lighting state of the two LEDs.

As shown in FIG. 2 , the chain saw 1 has a motor drive section 30 . The motor drive unit 30 receives power supply from the battery 9 in the battery pack 8 and drives and controls the motor 10 . In this embodiment, the motor 10 is a 3-phase brushless motor. The motor drive section 30 includes a drive circuit 32 , a gate circuit 34 , a control circuit 36 and a regulator 40 .

The drive circuit 32 is a circuit for receiving power supply from the battery 9 and causing a current to flow through each phase winding of the motor 10 . In this embodiment, the drive circuit 32 is configured as a three-phase full bridge circuit including six switching elements Q1, Q2, Q3, Q4, Q5, Q6. In this embodiment, the switching elements Q1-Q6 are MOSFETs.

In the drive circuit 32, the switching elements Q1 to Q3 are provided between the terminals U, V, W of the motor 10 and the power supply line connected to the positive electrode side of the battery 9. FIG. The switching elements Q4 to Q6 are provided between each terminal U, V, W of the motor 10 and a ground line connected to the negative electrode side of the battery 9. As shown in FIG.

The gate circuit 34 turns on/off the switching elements Q1 to Q6 in the drive circuit 32 in accordance with the control signal output from the control circuit 36, thereby causing a current to flow through each phase winding of the motor 10, thereby driving the motor 10. It is a circuit that rotates.

The control circuit 36 is mainly composed of a microcomputer having a CPU, ROM, RAM and the like. Various functions of the microcomputer are realized by executing a program stored in a non-transitional substantive recording medium by the CPU. In this example, the ROM corresponds to a non-transitional substantive recording medium storing programs. Also, by executing this program, a method corresponding to the program is executed. A part or all of the functions executed by the CPU may be configured as hardware using one or a plurality of ICs or the like. Also, the number of microcomputers constituting the control circuit 36 may be one or more.

The control circuit 36 includes a non-volatile memory 38 for storing the states and usage states of the motor 10 and the battery 9 to be controlled as history information.
The motor drive section 30 includes a battery voltage detection section 42 , a current detection circuit 44 and a temperature sensor 46 . A battery voltage detector 42 detects the voltage of the battery 9 . A current detection circuit 44 detects the current flowing through the motor 10 . The temperature sensor 46 detects the temperature of the motor driving section 30 (hereinafter referred to as controller temperature).

The chain saw 1 also includes a rotation sensor 50 that detects the rotational position and number of rotations of the motor 10, and a temperature sensor 52 that detects the temperature of the bolt 6 fixed to the guide bar 4 (hereinafter referred to as outer shell temperature).

The drive switch 18 , main power switch 21 , state display section 22 , battery voltage detection section 42 , current detection circuit 44 , temperature sensor 46 , rotation sensor 50 and temperature sensor 52 described above are connected to the control circuit 36 .

The battery pack 8 also includes a monitoring circuit (not shown). The monitoring circuit monitors the state of the battery 9 (for example, temperature and cell voltage) and outputs a stop signal to stop discharging from the battery 9 when an abnormality occurs.

The motor drive section 30 includes a data communication section 48 that relays communication between the monitoring circuit of the battery pack 8 and the control circuit 36 . Therefore, the control circuit 36 can receive a stop signal from the battery pack 8 via the data communication unit 48 to stop driving the motor 10 and acquire the state of the battery 9 .

The regulator 40 receives power from the battery 9 , generates a power supply voltage Vcc for operating the control circuit 36 , and supplies power to the internal circuits of the motor driving section 30 .
When the main power switch 21 is pressed, a signal is output to the control circuit 36 and a signal is output to the regulator 40 . Regulator 40 receives a signal from main power switch 21 to generate power supply voltage Vcc, and supplies generated power supply voltage Vcc to control circuit 36 . As a result, the control circuit 36 is activated and executes motor control processing and temperature protection determination processing. Control circuit 36 also outputs a signal to regulator 40 so that regulator 40 continues to supply power supply voltage Vcc. As a result, the regulator 40 continues to generate the power supply voltage Vcc even when the main power switch 21 is released from the pressed state. When the main power switch 21 is pressed while the power supply voltage Vcc is being supplied to the control circuit 36, the control circuit 36 causes the regulator 40 to stop generating the power supply voltage Vcc. Therefore, change the state of the output port of the microcomputer.

First, the procedure of motor control processing executed by the control circuit 36 will be described. The motor control process is a process that is repeatedly executed while the control circuit 36 is operating.
When the motor control process is executed, as shown in FIG. 3, the control circuit 36 first determines in S10 whether or not the drive switch 18 is on. Here, when the drive switch 18 is in the ON state, the control circuit 36 determines in S20 whether or not the temperature protection flag F1 provided in the RAM is set. In the following description, setting a flag means setting the value of the flag to 1, and clearing the flag means setting the value of the flag to 0.

Here, when the temperature protection flag F1 is cleared, the control circuit 36 sets the target rotational speed Rt provided in the RAM to 10000 rpm in S30. Then, in S40, the control circuit 36 calls a motor drive process for driving the motor 10 at the target rotation speed Rt, and once terminates the motor control process. On the other hand, if the temperature protection flag F1 is set in S20, the control circuit 36 proceeds to S50.

Also, in S10, if the drive switch 18 is not in the ON state, the control circuit 36 proceeds to S50.
After shifting to S50, the control circuit 36 sets the target rotation speed Rt to 0 rpm. Then, in S60, the control circuit 36 calls a motor stop process for stopping the driving of the motor 10, and temporarily ends the motor control process.

Next, the procedure of temperature protection determination processing executed by the control circuit 36 will be described. The temperature protection determination process is a process that is repeatedly executed while the control circuit 36 is operating.
When the temperature protection determination process is executed, the control circuit 36 first determines in S110 whether or not the initial temperature calculation completion flag F2 provided in the RAM is set, as shown in FIG. Here, when the initial temperature calculation completion flag F2 is set, the control circuit 36 acquires the value stored in the motor rotation speed Rnow provided in the RAM in S120. The motor rotation speed Rnow stores the motor rotation speed calculated by the control circuit 36 based on the detection result indicated by the detection signal input from the rotation sensor 50 .

Then, in S130, the control circuit 36 acquires the value stored in the current estimated temperature Tnow provided in the RAM. The current estimated temperature Tnow stores the temperature of the nut 7 estimated by the control circuit 36 .

Further, in S140, the control circuit 36 calculates the final temperature based on the motor rotation speed obtained in S120, and stores the calculated final temperature in the final temperature Tfin provided in the RAM. Note that the control circuit 36 estimates the ultimate temperature using, for example, a map or an arithmetic expression that indicates the correspondence relationship between the motor rotation speed and the ultimate temperature.

Further, in S150, the control circuit 36 calculates the difference between the temperature stored in the current estimated temperature Tnow and the final temperature stored in the final temperature Tfin. store in

Further, in S160, the control circuit 36 stores the division value obtained by dividing the value stored in the difference Tdif by a preset coefficient in the temperature change amount Ta provided in the RAM.
Further, in S170, the control circuit 36 stores the added value obtained by adding the value stored in the current estimated temperature Tnow and the value stored in the temperature change amount Ta in the current estimated temperature Tnow.

Then, in S180, the control circuit 36 determines whether or not the value stored in the current estimated temperature Tnow is equal to or greater than a preset temperature protection determination value TH1. Here, if the value stored in the current estimated temperature Tnow is equal to or greater than the temperature protection determination value TH1, the control circuit 36 sets the temperature protection flag F1 in S190, and temporarily terminates the temperature protection determination process. do.

On the other hand, if the value stored in the current estimated temperature Tnow is less than the temperature protection determination value TH1, the control circuit 36 changes the value stored in the current estimated temperature Tnow to the preset value in S200. It is determined whether or not it is equal to or less than the protection cancellation determination value TH2. Here, if the value stored in the current estimated temperature Tnow is equal to or less than the protection release determination value TH2, the control circuit 36 clears the temperature protection flag F1 in S210, and temporarily terminates the temperature protection determination process. do. On the other hand, if the value stored in the current estimated temperature Tnow exceeds the protection release determination value TH2, the temperature protection determination process is once terminated.

Further, when the initial temperature calculation completion flag F2 is cleared at S110, the control circuit 36 executes the initial temperature calculation process at S220, and once terminates the temperature protection determination process.

Next, the procedure of the initial temperature calculation process executed in S220 will be described.
When the initial temperature calculation process is executed, the control circuit 36, as shown in FIG. store in

Then, in S320, the control circuit 36 stores the value stored in the controller temperature Tcnt in the current estimated temperature Tnow. Further, in S330, the control circuit 36 sets the initial temperature calculation completion flag F2 and terminates the initial temperature calculation process.

The chain saw 1 configured as described above includes a main body 5 , a guide bar 4 , a saw chain 3 , a nut 7 and a motor drive section 30 . The main body 5 accommodates therein a motor 10 configured to generate driving force by rotating. A guide bar 4 is fixed to the main body 5 so as to protrude from the main body 5 . The saw chain 3 is attached along the outer periphery of the guide bar 4 and configured to rotate along the outer periphery of the guide bar 4 by the driving force generated by the motor 10 . A nut 7 is arranged outside the body 5 to secure the guide bar 4 to the body 5 . The motor drive unit 30 stops the rotation of the motor 10 when a preset protection condition indicating that the temperature of the nut 7 (hereinafter referred to as nut temperature) is equal to or higher than a preset protection temperature is satisfied. Execute the process.

In this manner, the chain saw 1 can stop the rotation of the motor 10 when the temperature of the nut 7 rises above the protection temperature. Therefore, the chain saw 1 can suppress an increase in temperature of the nut 7 due to frictional heat generated between the saw chain 3 and the guide bar 4 .

Also, the motor drive unit 30 estimates the current estimated temperature Tnow based on the rotation speed of the motor 10 . The protection condition is that the current estimated temperature Tnow is equal to or higher than the temperature protection determination value TH1. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so the configuration of the chain saw 1 can be simplified. .

In the embodiment described above, the motor 10 corresponds to the drive source, the main body 5 corresponds to the main body portion, the nut 7 corresponds to the fixing member, and S10 to S60 and S180 to S210 correspond to processing as the control circuit. .

Further, S110 to S170 and S220 correspond to the processing of the temperature estimating section, the current estimated temperature Tnow corresponds to the member temperature, and the temperature protection determination value TH1 corresponds to the protection temperature.
(Second embodiment)
A second embodiment of the present disclosure will be described below with reference to the drawings. In addition, in the second embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the second embodiment differs from that of the first embodiment in that the motor control process and temperature protection determination process are changed.
First, the procedure of motor control processing of the second embodiment will be described.

When the motor control process of the second embodiment is executed, as shown in FIG. 6, the control circuit 36 first determines in S410 whether or not the drive switch 18 is in the ON state. Here, if the drive switch 18 is in the ON state, the control circuit 36 determines in S420 whether or not the temperature protection flag F1 is set.

Here, when the temperature protection flag F1 is cleared, the control circuit 36 sets the target rotational speed Rt to 10000 rpm in S430, and proceeds to S450. On the other hand, if the temperature protection flag F1 is set, the control circuit 36 sets the target rotational speed Rt to 5000 rpm in S440, and proceeds to S450.

Then, after proceeding to S450, the control circuit 36 calls motor drive processing for driving the motor 10 at the target rotation speed Rt, and temporarily terminates the motor control processing.
If the drive switch 18 is not turned on at S410, the control circuit 36 sets the target rotational speed Rt to 0 rpm at S460. At S470, the control circuit 36 calls a motor stop process for stopping the driving of the motor 10, and once ends the motor control process.

Next, the procedure of temperature protection determination processing according to the second embodiment will be described.
When the temperature protection determination process of the second embodiment is executed, the control circuit 36, as shown in FIG. do.

Then, in S520, the control circuit 36 determines whether or not the value stored in the motor rotation speed Rnow exceeds 9000 rpm. Here, if the value stored in the motor rotation speed Rnow exceeds 9000 rpm, the control circuit 36 stores 20 in the counter change amount ΔC provided in the RAM in S530. transition to

On the other hand, if the value stored in the motor rotation speed Rnow is 9000 rpm or less, the control circuit 36 determines in S540 whether or not the value stored in the motor rotation speed Rnow exceeds 7000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 7000 rpm, the control circuit 36 stores 10 in the counter change amount ΔC in S550, and proceeds to S630.

On the other hand, if the value stored in the motor rotation speed Rnow is 7000 rpm or less, the control circuit 36 determines in S560 whether or not the value stored in the motor rotation speed Rnow exceeds 5000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 5000 rpm, the control circuit 36 stores 5 in the counter change amount ΔC in S570, and proceeds to S630.

On the other hand, if the value stored in the motor rotation speed Rnow is 5000 rpm or less, the control circuit 36 determines in S580 whether or not the value stored in the motor rotation speed Rnow exceeds 3000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 3000 rpm, the control circuit 36 stores -5 in the counter change amount ΔC in S590, and proceeds to S630.

On the other hand, if the value stored in the motor rotation speed Rnow is 3000 rpm or less, the control circuit 36 determines in S600 whether or not the value stored in the motor rotation speed Rnow exceeds 1000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 1000 rpm, the control circuit 36 stores -10 in the counter change amount ΔC in S610, and proceeds to S630.

On the other hand, if the value stored in the motor rotation speed Rnow is 1000 rpm or less, the control circuit 36 stores -20 in the counter change amount ΔC in S620, and proceeds to S630.

Then, in S630, the control circuit 36 stores the added value of the value stored in the heat generation counter Ct provided in the RAM and the value stored in the counter change amount ΔC in the heat generation counter Ct. .

Further, the control circuit 36 determines in S630 whether or not the heat generation counter Ct is underflowing. That is, the control circuit 36 determines whether the value stored in the heat generation counter Ct is smaller than zero. Here, if the value stored in the heat generation counter Ct is smaller than 0, the control circuit 36 determines that the heat generation counter Ct is underflowing, and stores 0 in the heat generation counter Ct in S650. , S660. On the other hand, if the value stored in the heat generation counter Ct is 0 or more, the control circuit 36 determines that the heat generation counter Ct does not underflow, and proceeds to S660.

After shifting to S660, the control circuit 36 determines whether or not the temperature protection flag F1 is cleared. Here, if the temperature protection flag F1 is cleared, the control circuit 36 determines in S670 whether the value stored in the heat generation counter Ct is equal to or greater than a preset temperature protection determination value TH3. to judge whether Here, if the value stored in the heat generation counter Ct is equal to or greater than the temperature protection determination value TH3, the control circuit 36 sets the temperature protection flag F1 in S680, and once terminates the temperature protection determination process. . On the other hand, if the value stored in the heat generation counter Ct is less than the temperature protection determination value TH3, the control circuit 36 once terminates the temperature protection determination process.

If the temperature protection flag F1 is set in S660, the control circuit 36 determines in S690 that the value stored in the heat generation counter Ct is equal to or less than the preset protection cancellation determination value TH4. or not. Here, if the value stored in the heat generation counter Ct is equal to or less than the protection release determination value TH4, the control circuit 36 clears the temperature protection flag F1 in S700, and temporarily terminates the temperature protection determination process. . On the other hand, when the value stored in the heat generation counter Ct exceeds the protection release determination value TH4, the control circuit 36 once terminates the temperature protection determination process.

The chain saw 1 configured as described above includes a main body 5 , a guide bar 4 , a saw chain 3 , a nut 7 and a motor drive section 30 . When a protection condition indicating that the temperature of the nut 7 is equal to or higher than a preset protection temperature is satisfied, the motor drive unit 30 performs reduction processing to reduce rotation of the motor 10 more than when the protection condition is not satisfied. to run.

In this manner, the chain saw 1 can reduce the rotation of the motor 10 when the temperature of the nut 7 rises above the protection temperature. Therefore, the chain saw 1 can suppress an increase in temperature of the nut 7 due to frictional heat generated between the saw chain 3 and the guide bar 4 .

Also, the motor drive unit 30 estimates the heat generation counter Ct based on the rotation speed of the motor 10 . The protection condition is that the heat generation counter Ct is equal to or greater than the temperature protection determination value TH3. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S410 to S470 and S660 to S700 correspond to the processing of the control circuit, S510 to S650 correspond to the processing of the heat generation amount estimator, the heat generation counter Ct corresponds to the member heat generation amount, The temperature protection determination value TH3 corresponds to the protection heat generation amount.

(Third Embodiment)
A third embodiment of the present disclosure will be described below with reference to the drawings. Note that in the third embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chainsaw 1 of the third embodiment differs from that of the first embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing of the third embodiment will be described.

When the temperature protection determination process of the third embodiment is executed, the control circuit 36 first determines in S810 whether or not the drive switch 18 is in the ON state, as shown in FIG. Here, if the drive switch 18 is not in the ON state, the control circuit 36 clears the temperature protection flag F1 in S820. Furthermore, in S830, the control circuit 36 stores 0 in the ON time Ton provided in the RAM, and once ends the temperature protection determination process.

If the drive switch 18 is in the ON state at S810, the control circuit 36 calculates the time elapsed since the drive switch 18 was turned ON (hereinafter referred to as ON time) at S840. The on-time obtained is stored in the on-time Ton.

Then, in S850, the control circuit 36 determines whether or not the value stored in the ON time Ton is equal to or greater than a preset temperature protection determination value TH5. Here, if the value stored in the ON time Ton is equal to or greater than the temperature protection determination value TH5, the control circuit 36 sets the temperature protection flag F1 in S860, and once terminates the temperature protection determination process. . On the other hand, when the value stored in the ON time Ton is less than the temperature protection determination value TH5, the control circuit 36 once terminates the temperature protection determination process.

In the chain saw 1 configured as described above, the motor drive unit 30 measures the ON time Ton during which the drive switch 18 operated by the user to generate the driving force of the motor 10 is operated. The protection condition is that the measured on-time Ton is equal to or greater than a preset temperature protection judgment value TH5. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S820, and S850 to S860 correspond to the processing of the control circuit, S810, S830, and S840 correspond to the processing of the time measuring section, and the ON time Ton corresponds to the operation time. The temperature protection judgment value TH5 corresponds to the operation protection time.

(Fourth embodiment)
A fourth embodiment of the present disclosure will be described below with reference to the drawings. In addition, in the fourth embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the fourth embodiment differs from that of the first embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing according to the fourth embodiment will be described.

When the temperature protection determination process of the fourth embodiment is executed, as shown in FIG. 9, the control circuit 36 first determines in S910 whether or not the motor 10 is being driven. Here, if the motor 10 is not being driven, the control circuit 36 determines in S920 whether or not the drive switch 18 is on. Here, when the drive switch 18 is in the ON state, the control circuit 36 once terminates the temperature protection determination process. On the other hand, if the drive switch 18 is not on, the control circuit 36 clears the temperature protection flag F1 in S930. Furthermore, in S940, the control circuit 36 stores 0 in the drive time Tdr provided in the RAM, and once terminates the temperature protection determination process.

If the motor 10 is being driven at S910, the control circuit 36 calculates the time elapsed since the motor 10 started driving (hereinafter referred to as driving time) at S950. The time is stored in drive time Tdr.

Then, in S960, the control circuit 36 determines whether or not the value stored in the drive time Tdr is equal to or greater than a preset temperature protection determination value TH6. Here, if the value stored in the drive time Tdr is equal to or greater than the temperature protection determination value TH6, the control circuit 36 sets the temperature protection flag F1 in S970, and once terminates the temperature protection determination process. . On the other hand, when the value stored in the drive time Tdr is less than the temperature protection determination value TH6, the control circuit 36 once terminates the temperature protection determination process.

In the chain saw 1 configured as described above, the motor driving section 30 measures the driving time Tdr during which the motor 10 is driven. The protection condition is that the measured drive time Tdr is equal to or greater than a preset temperature protection determination value TH6. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S930, and S960 to S970 correspond to processing as a control circuit, S910 to S930 and S950 correspond to processing as a time measuring unit, and drive time Tdr corresponds to operation time. The temperature protection judgment value TH6 corresponds to the operation protection time.

(Fifth embodiment)
A fifth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the fifth embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the fifth embodiment differs from that of the first embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing of the fifth embodiment will be described.

When the temperature protection determination process of the fifth embodiment is executed, as shown in FIG. 10, the control circuit 36 first determines in S1010 whether or not the drive switch 18 is in the ON state. Here, if the drive switch 18 is not in the ON state, the control circuit 36 determines, in S1020, from the value stored in the ON time Ton provided in the RAM, the elapsed time since the previous temperature protection determination process was completed. The subtracted value obtained by subtracting the value corresponding to the time taken is stored in the ON time Ton.

Then, in S1030, the control circuit 36 determines whether or not the value stored in the ON time Ton is equal to or less than a preset protection cancellation determination value TH7. Here, if the value stored in the on-time Ton is equal to or less than the protection release determination value TH7, the control circuit 36 clears the temperature protection flag F1 in S1040, and once terminates the temperature protection determination process. . On the other hand, when the value stored in the on-time Ton exceeds the protection release determination value TH7, the control circuit 36 once terminates the temperature protection determination process.

In S1010, if the drive switch 18 is in the ON state, the control circuit 36 determines in S1050 the value stored in the ON time Ton provided in the RAM and the value stored in the previous temperature protection determination process. A value obtained by adding a value corresponding to the time that has elapsed since then is stored in the ON time Ton.

Then, in S1060, the control circuit 36 determines whether or not the value stored in the ON time Ton is equal to or greater than a preset temperature protection determination value TH5. Here, if the value stored in the on-time Ton is equal to or greater than the temperature protection determination value TH5, the control circuit 36 sets the temperature protection flag F1 in S1070, and once terminates the temperature protection determination process. . On the other hand, when the value stored in the ON time Ton is less than the temperature protection determination value TH5, the control circuit 36 once terminates the temperature protection determination process.

In the chain saw 1 configured as described above, the motor drive unit 30 measures the ON time Ton during which the drive switch 18 operated by the user to generate the driving force of the motor 10 is operated. The protection condition is that the measured on-time Ton is equal to or greater than a preset temperature protection judgment value TH5. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S1030, S1040, S1060, and S1070 correspond to the processing of the control circuit, S1010, S1020, and S1050 correspond to the processing of the time measurement unit, and the ON time Ton is the operation time. , and the temperature protection determination value TH5 corresponds to the protection time for operation.

(Sixth embodiment)
A sixth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the sixth embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the sixth embodiment differs from that of the first embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing of the sixth embodiment will be described.

When the temperature protection determination process of the sixth embodiment is executed, as shown in FIG. 11, the control circuit 36 first determines in S1110 whether or not the motor 10 is being driven. Here, if the motor 10 is not being driven, the control circuit 36 determines in S1120 whether or not the drive switch 18 is on. Here, when the drive switch 18 is in the ON state, the control circuit 36 once terminates the temperature protection determination process. On the other hand, if the drive switch 18 is not in the ON state, the control circuit 36 determines in S1130 that the value stored in the drive time Tdr provided in the RAM has elapsed since the previous temperature protection determination process was completed. A subtracted value obtained by subtracting the value corresponding to the time is stored in the driving time Tdr.

Then, in S1140, the control circuit 36 determines whether or not the value stored in the drive time Tdr is equal to or less than a preset protection cancellation determination value TH8. Here, if the value stored in the drive time Tdr is equal to or less than the protection release determination value TH8, the control circuit 36 clears the temperature protection flag F1 in S1150, and once terminates the temperature protection determination process. . On the other hand, when the value stored in the drive time Tdr exceeds the protection release determination value TH8, the control circuit 36 once terminates the temperature protection determination process.

If the motor 10 is being driven at S1110, the control circuit 36 changes the value stored in the drive time Tdr and the time elapsed since the previous temperature protection determination process was completed at S1160. The added value obtained by adding the corresponding value is stored in the drive time Tdr.

Then, in S1170, the control circuit 36 determines whether or not the value stored in the drive time Tdr is equal to or greater than a preset temperature protection determination value TH6. Here, if the value stored in the drive time Tdr is equal to or greater than the temperature protection determination value TH6, the control circuit 36 sets the temperature protection flag F1 in S1180, and once terminates the temperature protection determination process. . On the other hand, when the value stored in the drive time Tdr is less than the temperature protection determination value TH6, the control circuit 36 once terminates the temperature protection determination process.

In the chain saw 1 configured as described above, the motor driving section 30 measures the driving time Tdr during which the motor 10 is driven. The protection condition is that the measured drive time Tdr is equal to or greater than a preset temperature protection determination value TH6. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S1140, S1150, S1170, and S1180 correspond to the processing of the control circuit, S1110 to S1130, and S1160 correspond to the processing of the time measurement section, and the drive time Tdr is the operation time. , and the temperature protection determination value TH6 corresponds to the protection time for operation.

(Seventh embodiment)
A seventh embodiment of the present disclosure will be described below with reference to the drawings. In addition, in the seventh embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the seventh embodiment differs from that of the first embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing of the seventh embodiment will be described.

When the temperature protection determination process of the seventh embodiment is executed, as shown in FIG. 12, the control circuit 36 first determines in S1210 whether or not the motor 10 is being driven. Here, if the motor 10 is not being driven, the control circuit 36 determines in S1270 whether or not the drive switch 18 is in the OFF state. Here, if the drive switch 18 is not in the off state, the control circuit 36 once terminates the temperature protection determination process. On the other hand, when the drive switch 18 is in the OFF state, the process proceeds to S1250.

If the motor 10 is being driven at S1210, the control circuit 36 converts the outer shell temperature indicated by the detection signal input from the temperature sensor 52 to the outer shell temperature Tout provided in the RAM at S1220. store in

Then, in S1230, control circuit 36 determines whether or not the value stored in outer shell temperature Tout is equal to or greater than preset temperature protection determination value TH9. Here, if the value stored in the outer shell temperature Tout is equal to or higher than the temperature protection determination value TH9, the control circuit 36 sets the temperature protection flag F1 in S1240, and temporarily terminates the temperature protection determination process. do. On the other hand, if the value stored in outer shell temperature Tout is less than temperature protection determination value TH9, control circuit 36 proceeds to S1250.
Then, in S1250, the control circuit 36 determines whether or not the value stored in the outer shell temperature Tout is equal to or less than a preset protection cancellation determination value TH10. Here, if the value stored in the outer shell temperature Tout is equal to or lower than the protection release determination value TH10, the control circuit 36 clears the temperature protection flag F1 in S1260, and temporarily terminates the temperature protection determination process. do. On the other hand, when the value stored in the outer shell temperature Tout exceeds the protection release determination value TH10, the control circuit 36 once terminates the temperature protection determination process.

The chain saw 1 configured in this manner includes a temperature sensor 52 for detecting the outer shell temperature Tout, and the protection condition is that the outer shell temperature Tout is higher than the temperature protection threshold value TH9. As described above, the chain saw 1 is provided with the temperature sensor 52 that directly detects the temperature of the nut 7, so it can be accurately determined whether or not the protection condition is satisfied.

In the embodiment described above, S10 to S60 and S1210 to S1260 correspond to the processing as the control circuit, the temperature sensor 52 corresponds to the temperature detection section, the outer shell temperature Tout corresponds to the member temperature, and the temperature protection judgment value TH9 corresponds to the protection temperature.

(Eighth embodiment)
An eighth embodiment of the present disclosure will be described below with reference to the drawings. In addition, in the eighth embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the eighth embodiment differs from the first embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing of the eighth embodiment will be described.

When the temperature protection determination process of the eighth embodiment is executed, as shown in FIG. 13, the control circuit 36 first determines in S1310 whether or not the initial temperature calculation completion flag F2 is set. Here, if the initial temperature calculation completion flag F2 is set, the control circuit 36 executes a tension level detection process at S1320 to detect the tension level. The tension level indicates the degree of tension of the saw chain 3 attached to the guide bar 4 . A value indicating the tension level is stored in the tension level Lch provided in the RAM.

Then, in S1330, the control circuit 36 acquires the value stored in the motor rotation speed Rnow in the same manner as in S120.
Also, in S1340, the control circuit 36 acquires the value stored in the current estimated temperature Tnow in the same manner as in S130.

In S1350, the control circuit 36 calculates the ultimate temperature based on the motor rotation speed acquired in S130 and the tension level detected in S1320, and saves the calculated ultimate temperature as the ultimate temperature Tfin provided in the RAM. Store. Note that the control circuit 36 estimates the ultimate temperature using, for example, a map or an arithmetic expression that indicates the correspondence relationship between the motor rotation speed and the tension level and the ultimate temperature.

Further, in S1360, the control circuit 36 calculates the temperature rise coefficient based on the tension level detected in S1320, and stores the calculated temperature rise coefficient in the temperature rise coefficient Tpar provided in the RAM. Note that the control circuit 36 calculates the temperature rise coefficient using, for example, a map or an arithmetic expression that indicates the correspondence relationship between the tension level and the temperature rise coefficient. The temperature rise factor is set to have a negative correlation with the tension level.

In S1370, the control circuit 36 also stores a subtraction value obtained by subtracting the temperature stored in the current estimated temperature Tnow from the final temperature stored in the final temperature Tfin in the difference Tdif.

Further, in S1380, the control circuit 36 stores the value obtained by dividing the value stored in the difference Tdif by the value stored in the temperature increase coefficient Tpar as the temperature change amount Ta.
In S1390, the control circuit 36 adds the value stored in the current estimated temperature Tnow and the value stored in the temperature change amount Ta to the current estimated temperature Tnow store in

Then, in S1400, control circuit 36 determines whether or not the value stored in current estimated temperature Tnow is equal to or greater than temperature protection determination value TH1, in the same manner as in S180. Here, if the value stored in the current estimated temperature Tnow is equal to or higher than the temperature protection determination value TH1, the control circuit 36 sets the temperature protection flag F1 in S1410, and temporarily terminates the temperature protection determination process. do.

On the other hand, if the value stored in the current estimated temperature Tnow is less than the temperature protection determination value TH1, the control circuit 36, in S1420, similarly to S200, determines the value stored in the current estimated temperature Tnow. is less than or equal to the protection cancellation judgment value TH2. Here, if the value stored in the current estimated temperature Tnow is equal to or less than the protection release determination value TH2, the control circuit 36 clears the temperature protection flag F1 in S1430, and temporarily terminates the temperature protection determination process. do. On the other hand, if the value stored in the current estimated temperature Tnow exceeds the protection release determination value TH2, the temperature protection determination process is once terminated.

If the initial temperature calculation completion flag F2 is cleared at S1310, the control circuit 36 executes the initial temperature calculation process at S1440 in the same manner as at S220, and temporarily terminates the temperature protection determination process. do.

Next, the procedure of the tension level detection process executed in S1320 will be described.
When the tension level detection process is executed, the control circuit 36 first determines in S1510 whether or not the motor 10 is being driven, as shown in FIG. Here, if the motor 10 is not being driven, the control circuit 36 clears the tension level detection completion flag F3 provided in the RAM at S1520, and ends the tension level detection processing.

On the other hand, if the motor 10 is being driven, the control circuit 36 determines in S1530 whether or not the tension level detection completion flag F3 is set. Here, if the tension level detection completion flag F3 is set, the control circuit 36 ends the tension level detection process.

On the other hand, if the tension level detection completion flag F3 is cleared, the control circuit 36 acquires the value stored in the motor rotation speed Rnow in S1540 in the same manner as in S120.

Furthermore, in S1550, the control circuit 36 calculates the difference between the maximum value and the minimum value of the motor rotation speed within the most recent fluctuation amount calculation time (for example, 5 seconds) as the motor rotation speed fluctuation, and calculates the calculated motor rotation speed. The variation is stored in the motor speed variation ΔR provided in RAM.

Then, in S1560, the control circuit 36 determines whether or not the value stored in the motor rotational speed variation ΔR is equal to or less than a preset level determination value TH11. Here, if the value stored in the motor rotation speed fluctuation ΔR is equal to or less than the level judgment value TH11, the control circuit 36 acquires the value stored in the motor current Imt provided in the RAM in S1570. do. The value of the motor current indicated by the detection signal input from the current detection circuit 44 is stored in the motor current Imt.

Also, in S1580, the control circuit 36 calculates the tension level based on the motor current acquired in S1570, and stores the calculated tension level in the tension level Lch provided in the RAM. Note that the control circuit 36 calculates the tension level using, for example, a map or an arithmetic expression that indicates the correspondence relationship between the motor current and the tension level.

Then, in S1590, the control circuit 36 sets the tension level detection completion flag F3, and terminates the tension level detection process.
If the value stored in the motor rotation speed fluctuation ΔR exceeds the level judgment value TH11 in S1560, the preset initial value is stored in the tension level Lch in S1600, and the tension level is detected. End the process.

In the chain saw 1 configured as described above, the motor driving section 30 detects the tension level indicating the tension of the saw chain 3 with respect to the guide bar 4 . Then, the motor drive unit 30 estimates the current estimated temperature Tnow in accordance with the tension level so that the current estimated temperature Tnow increases as the tension of the saw chain 3 increases. As a result, the chain saw 1 can estimate the current estimated temperature Tnow using the tension level, so it can accurately determine whether or not the protection condition is satisfied.

In the embodiment described above, S10 to S60 and S1400 to S1430 correspond to processing as a control circuit, S1510 to S1600 correspond to processing as a level detection section, and S1310 to S1390 and S1440 correspond to processing as a temperature estimation section. corresponds to

(Ninth embodiment)
A ninth embodiment of the present disclosure will be described below with reference to the drawings. In addition, in the ninth embodiment, portions different from the eighth embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chainsaw 1 of the ninth embodiment differs from that of the eighth embodiment in that the tension level detection process is changed.
Here, the procedure of the tension level detection process of the ninth embodiment will be described.

When the tension level detection process of the ninth embodiment is executed, as shown in FIG. 15, the control circuit 36 first determines in S1710 whether or not the motor 10 is being driven. Here, if the motor 10 is not being driven, the control circuit 36 clears the tension level detection completion flag F3 in S1720, and ends the tension level detection process.

On the other hand, if the motor 10 is being driven, the control circuit 36 determines in S1730 whether or not the tension level detection completion flag F3 is set. Here, if the tension level detection completion flag F3 is set, the control circuit 36 ends the tension level detection process.

On the other hand, if the tension level detection completion flag F3 is cleared, in S1740 the control circuit 36 calculates the driving time that has elapsed since the motor 10 started driving, and stores the calculated driving time in the RAM. is stored in the driving time Tdr provided in .

Then, in S1750, the control circuit 36 determines whether or not the value stored in the drive time Tdr is equal to or greater than a preset level detection determination value TH12. Here, if the value stored in the drive time Tdr is less than the level detection determination value TH12, the control circuit 36 acquires the value stored in the motor current Imt provided in the RAM at S1760. do.

Further, in S1770, the control circuit 36 compares the value obtained in S1760 with the value stored in the maximum motor current Imax provided in the RAM, and stores the larger value in the maximum motor current Imax.

Then, in S1780, the control circuit 36 stores the preset initial value in the tension level Lch, and terminates the tension level detection process.
Further, in S1750, if the value stored in the drive time Tdr is equal to or greater than the temperature protection determination value TH12, the control circuit 36 determines in S1790 the tension level based on the value stored in the maximum motor current Imax. is calculated, and the calculated tension level is stored in the tension level Lch. Note that the control circuit 36 calculates the tension level using, for example, a map or an arithmetic expression that indicates the correspondence relationship between the maximum motor current and the tension level.
Then, in S1800, the control circuit 36 sets the tension level detection completion flag F3 and terminates the tension level detection process.

In the chain saw 1 configured as described above, the motor driving section 30 detects the tension level indicating the tension of the saw chain 3 with respect to the guide bar 4 . Then, the motor drive unit 30 estimates the current estimated temperature Tnow in accordance with the tension level so that the current estimated temperature Tnow increases as the tension of the saw chain 3 increases. As a result, the chain saw 1 can estimate the current estimated temperature Tnow using the tension level, so it can accurately determine whether or not the protection condition is satisfied.

In the embodiment described above, S1710 to S1790 correspond to the processing of the level detection section.
(Tenth embodiment)
A tenth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the tenth embodiment, portions different from the eighth embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the tenth embodiment differs from that of the eighth embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing according to the tenth embodiment will be described.

When the temperature protection determination process of the tenth embodiment is executed, as shown in FIG. To detect.

Further, in S1920, the control circuit 36 calculates the counter increase rate based on the tension level detected in S1910, and stores the calculated counter increase rate in the counter increase rate Cpar provided in the RAM. Note that the control circuit 36 calculates the counter increase rate using, for example, a map or an arithmetic expression that indicates the correspondence relationship between the tension level and the counter increase rate. The counter increase rate is set to have a positive correlation with the tension level.

Also, in S1930, the control circuit 36 acquires the value stored in the motor rotation speed Rnow in the same manner as in S120.
Then, in S1940, control circuit 36 determines whether or not the value stored in motor rotation speed Rnow exceeds 10000 rpm. Here, if the value stored in the motor rotation speed Rnow exceeds 10000 rpm, the control circuit 36 stores 20 in the counter change amount ΔC in S1950, and proceeds to S2050.

On the other hand, if the value stored in the motor rotation speed Rnow is 10000 rpm or less, the control circuit 36 determines in S1960 whether or not the value stored in the motor rotation speed Rnow exceeds 8000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 8000 rpm, the control circuit 36 stores 10 in the counter change amount ΔC in S1970, and proceeds to S2050.

On the other hand, if the value stored in the motor rotation speed Rnow is 8000 rpm or less, the control circuit 36 determines in S1980 whether or not the value stored in the motor rotation speed Rnow exceeds 6000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 6000 rpm, the control circuit 36 stores 5 in the counter change amount ΔC in S1990, and proceeds to S2050.

On the other hand, if the value stored in the motor rotation speed Rnow is 6000 rpm or less, the control circuit 36 determines in S2000 whether or not the value stored in the motor rotation speed Rnow exceeds 4000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 4000 rpm, the control circuit 36 stores -5 in the counter change amount ΔC in S2010, and proceeds to S2050.

On the other hand, if the value stored in the motor rotation speed Rnow is 4000 rpm or less, the control circuit 36 determines in S2020 whether or not the value stored in the motor rotation speed Rnow exceeds 2000 rpm. do. Here, if the value stored in the motor rotation speed Rnow exceeds 2000 rpm, the control circuit 36 stores -10 in the counter change amount ΔC in S2030, and proceeds to S2050.

On the other hand, if the value stored in motor rotation speed Rnow is 2000 rpm or less, control circuit 36 stores -20 in counter change amount ΔC in S2040, and proceeds to S2050.

Then, in S2050, the control circuit 36 multiplies the value stored in the counter change amount ΔC by the value stored in the counter increase rate Cpar and stores the multiplied value in the counter change amount ΔC.

In S2060, the control circuit 36 also stores the added value of the value stored in the heat generation counter Ct provided in the RAM and the value stored in the counter change amount ΔC in the heat generation counter Ct. Note that when the added value overflows, the upper limit value is stored in the heat generation counter Ct.

Furthermore, the control circuit 36 determines in S2070 whether or not the heat generation counter Ct is underflowing. Here, if the heat generation counter Ct underflows, the control circuit 36 stores 0 in the heat generation counter Ct in S2080, and proceeds to S2090. On the other hand, if the heat generation counter Ct does not underflow, the control circuit 36 proceeds to S2090.

Then, in S2090, the control circuit 36 determines whether or not the temperature protection flag F1 is cleared. Here, if the temperature protection flag F1 is cleared, the control circuit 36 determines in S2100 whether or not the value stored in the heat generation counter Ct is equal to or greater than the temperature protection determination value TH3. Here, if the value stored in the heat generation counter Ct is equal to or greater than the temperature protection determination value TH3, the control circuit 36 sets the temperature protection flag F1 in S2110, and once terminates the temperature protection determination process. . On the other hand, if the value stored in the heat generation counter Ct is less than the temperature protection determination value TH3, the control circuit 36 once terminates the temperature protection determination process.

If the temperature protection flag F1 is set in S2090, the control circuit 36 determines in S2120 whether or not the value stored in the heat generation counter Ct is equal to or less than the protection cancellation determination value TH4. do. Here, if the value stored in the heat generation counter Ct is equal to or less than the protection cancellation determination value TH4, the control circuit 36 clears the temperature protection flag F1 in S2130, and temporarily terminates the temperature protection determination process. . On the other hand, when the value stored in the heat generation counter Ct exceeds the protection release determination value TH4, the control circuit 36 once terminates the temperature protection determination process.

In the chain saw 1 configured as described above, the motor driving section 30 detects the tension level indicating the tension of the saw chain 3 with respect to the guide bar 4 . Then, the motor drive unit 30 estimates the heat generation counter Ct according to the tension level so that the heat generation counter Ct increases as the tension of the saw chain 3 increases. As a result, the chain saw 1 can estimate the heat generation counter Ct using the tension level, so it can accurately determine whether or not the protection condition is satisfied.

In the embodiment described above, S10 to S60 and S2090 to S2130 correspond to the processing of the control circuit, and S1910 to S2080 correspond to the processing of the heat generation amount estimator.

(Eleventh embodiment)
An eleventh embodiment of the present disclosure will be described below with reference to the drawings. Note that in the eleventh embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the eleventh embodiment differs from the first embodiment in that a power holding process is added.
Here, the procedure of the power holding process executed by the control circuit 36 will be described. The power holding process is a process that is repeatedly executed while the control circuit 36 is operating.

When the power holding process is executed, as shown in FIG. 17, control circuit 36 first determines in S2210 whether or not motor 10 is being driven. Here, if the motor 10 is being driven, the control circuit 36 stores 0 in the power supply holding time Tvon provided in the RAM in S2220, and proceeds to S2290.

On the other hand, if the motor 10 is not being driven, the control circuit 36, in S2230, compares the value stored in the power holding time Tvon with the value corresponding to the time that has elapsed since the previous power holding process ended. is stored in the power holding time Tvon.

Then, in S2240, the control circuit 36 determines whether or not the value stored in the power holding time Tvon is equal to or greater than a preset power holding determination value TH13. Here, if the value stored in the power holding time Tvon is less than the power holding determination value TH13, the control circuit 36 proceeds to S2290.

On the other hand, if the value stored in the power retention time Tvon is equal to or greater than the power retention determination value TH13, the control circuit 36 acquires the value stored in the initial temperature Tini provided in the RAM in S2250. do. The initial temperature Tini stores the temperature of the nut 7 estimated by the control circuit 36 based on the controller temperature indicated by the detection signal input from the temperature sensor 46 when the control circuit 36 is activated.

Also, in S2260, the control circuit 36 acquires the value stored in the current estimated temperature Tnow.
Then, in S2270, control circuit 36 determines whether or not the value stored in current estimated temperature Tnow matches the value stored in initial temperature Tini. Here, if they match, the control circuit 36 performs processing to shut down the microcomputer of the control circuit 36 in S2280, and ends the power holding processing.

When the process proceeds to S2290, the control circuit 36 performs processing to maintain the power supply from the regulator 40 to the control circuit 36 in S2290, and temporarily terminates the power retention processing.
In the chain saw 1 configured as described above, the motor driving section 30 keeps the power supply to the control circuit 36 when the current estimated temperature Tnow exceeds the preset initial temperature Tini. As a result, the chain saw 1 can store the current estimated temperature Tnow until the current estimated temperature Tnow becomes equal to or lower than the initial temperature Tini. Therefore, even if the operator stops driving the chain saw 1 while the temperature of the nut 7 exceeds the initial temperature Tini and restarts the driving of the chain saw 1 immediately after that, the current It is possible to prevent the estimated temperature Tnow from being set to the initial value. As a result, the chain saw 1 can resume estimating the temperature of the nut 7 based on the stored current estimated temperature Tnow.

In the embodiment described above, S2210 to S2290 correspond to the processing of the temperature dependent holding section, the current estimated temperature Tnow corresponds to the member temperature, and the initial temperature Tini corresponds to the temperature holding determination value.

(12th embodiment)
A twelfth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the twelfth embodiment, portions different from the eleventh embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the twelfth embodiment differs from that of the eleventh embodiment in that the power holding process is changed.
The power holding process of the twelfth embodiment differs from that of the eleventh embodiment in that S2255 and S2275 are performed instead of S2250 to S2270.

That is, as shown in FIG. 18, when the value stored in the power holding time Tvon is equal to or greater than the power holding determination value TH13 in S2240, the control circuit 36 stores the value in the heat generation counter Ct in S2255. Get the value that is specified.

Then, in S2275, the control circuit 36 determines whether or not the value obtained from the heat generation counter Ct is 0. Here, if the value obtained from the heat generation counter Ct is 0, the control circuit 36 proceeds to S2280. On the other hand, if the value obtained from the heat generation counter Ct is not 0, the control circuit 36 proceeds to S2290.

In the chain saw 1 configured as described above, the motor driving section 30 keeps power supply to the control circuit 36 when the heat generation counter Ct exceeds zero. As a result, the chain saw 1 can store the heat generation counter Ct until the estimated heat generation counter Ct becomes 0 or less. Therefore, even if the operator stops driving the chain saw 1 while the heat generation counter Ct exceeds 0 and restarts the driving of the chain saw 1 immediately after that, the heat generation counter Ct is You can prevent it from being set to the initial value. As a result, the chain saw 1 can resume estimating the heat generation counter Ct based on the stored heat generation counter Ct.

In the above-described embodiment, S2210 to S2290 correspond to the calorific value dependent holding unit, the heat counter Ct corresponds to the member calorific value, and 0 corresponds to the calorific value holding determination value.

(13th embodiment)
A thirteenth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the thirteenth embodiment, portions different from the first embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chain saw 1 of the thirteenth embodiment differs from the first embodiment in that the temperature protection determination process is changed.
Here, the procedure of temperature protection determination processing of the thirteenth embodiment will be described.

When the temperature protection determination process of the thirteenth embodiment is executed, as shown in FIG. 19, the control circuit 36 first determines in S2410 whether or not the drive switch 18 is in the ON state. Here, if the drive switch 18 is not in the ON state, the control circuit 36 clears the temperature protection flag F1 in S2420, and proceeds to S2480.

On the other hand, when the drive switch 18 is in the ON state, the control circuit 36 acquires the value stored in the motor current Imt provided in the RAM in S2430. Then, in S2440, the control circuit 36 determines whether or not the value stored in the motor current Imt is equal to or greater than a preset current determination value TH14. In this embodiment, the current determination value TH14 is a value corresponding to 40A.

Here, if the value stored in the motor current Imt is equal to or less than the current determination value TH14, the control circuit 36, in S2450, stores the value stored in the no-load time Tnl provided in the RAM, A value obtained by adding a value corresponding to the time that has elapsed since the temperature protection determination process of (1) is completed is stored in the no-load time Tnl.

Then, in S2460, the control circuit 36 determines whether or not the value stored in the no-load time Tnl is equal to or greater than the preset temperature protection determination value TH15. In this embodiment, the temperature protection determination value TH15 is a value corresponding to 2 minutes.

Here, if the value stored in the no-load time Tnl is equal to or greater than the temperature protection determination value TH15, the control circuit 36 sets the temperature protection flag F1 in S2470, and once terminates the temperature protection determination process. do. On the other hand, if the value stored in the no-load time Tnl is less than the temperature protection determination value TH15, the control circuit 36 once terminates the temperature protection determination process.

In S2440, if the value stored in motor current Imt exceeds current determination value TH14, control circuit 36 proceeds to S2480.
After shifting to S2480, the control circuit 36 stores 0 in the no-load time Tnl, and once ends the temperature protection determination process.

In the chain saw 1 configured as described above, the motor drive unit 30 determines whether it is in a loaded state where the operator has started working or in a no-loaded state where the operator is not working. The protection condition is that the no-load time Tnl during which the motor 10 is driven in the no-load state is equal to or greater than a preset temperature protection determination value TH15. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S2420, S2460 and S2470 correspond to the processing of the control circuit, and S2410, S2430 to S2450 and S2480 correspond to the processing of the load determination section.

The no-load time Tnl corresponds to the no-load drive time, and the temperature protection determination value TH15 corresponds to the no-load protection time.
(14th embodiment)
A fourteenth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the fourteenth embodiment, portions different from the thirteenth embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chainsaw 1 of the fourteenth embodiment differs from that of the thirteenth embodiment in that the temperature protection determination process is changed.
The temperature protection determination process of the fourteenth embodiment differs from that of the thirteenth embodiment in that S2510 to S2540 are executed instead of S2420 and S2480.

That is, as shown in FIG. 20, in S2410, if the drive switch 18 is not in the ON state, the control circuit 36 proceeds to S2510. In S2440, if the value stored in motor current Imt exceeds current determination value TH14, control circuit 36 proceeds to S2510.

After shifting to S2510, the control circuit 36 determines whether or not the value stored in the no-load time Tnl is zero. Here, when the value stored in the no-load time Tnl is 0, the control circuit 36 once terminates the temperature protection determination process.

On the other hand, if the value stored in the no-load time Tnl is not 0, the control circuit 36, in S2520, determines from the value stored in the no-load time Tnl to A subtracted value obtained by subtracting a value corresponding to the elapsed time is stored in the no-load time Tnl.

Then, in S2530, the control circuit 36 determines whether or not the value stored in the no-load time Tnl is equal to or less than a preset protection cancellation determination value TH16. In this embodiment, the protection cancellation determination value TH16 is a value corresponding to 30 seconds.

Here, if the value stored in the no-load time Tnl is less than or equal to the protection release determination value TH16, the control circuit 36 clears the temperature protection flag F1 in S2520, and temporarily terminates the temperature protection determination process. do. On the other hand, when the value stored in the no-load time Tnl exceeds the protection release determination value TH16, the control circuit 36 once terminates the temperature protection determination process.

In the chain saw 1 configured as described above, the motor drive unit 30 determines whether it is in a loaded state where the operator has started working or in a no-loaded state where the operator is not working. The protection condition is that the no-load time Tnl during which the motor 10 is driven in the no-load state is equal to or greater than a preset temperature protection determination value TH15. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S2460, S2470, S2530 and S2540 correspond to the processing of the control circuit, and S2410, S2430 to S2450, S2510 and S2520 correspond to the processing of the load determination section.

(15th embodiment)
A fifteenth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the fifteenth embodiment, portions different from the thirteenth embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chainsaw 1 of the fifteenth embodiment differs from that of the thirteenth embodiment in that the temperature protection determination process is changed.
The temperature protection determination process of the fifteenth embodiment differs from that of the thirteenth embodiment in that S2610 and S2620 are executed instead of S2410.

That is, as shown in FIG. 21, when the temperature protection determination process of the fifteenth embodiment is executed, the control circuit 36 first determines in S2610 whether or not the motor 10 is being driven. Here, if the motor 10 is being driven, the control circuit 36 proceeds to S2430.

On the other hand, if the motor 10 is not being driven, the control circuit 36 determines in S2620 whether or not the drive switch 18 is on. Here, if the drive switch 18 is not in the off state, the control circuit 36 proceeds to S2480. On the other hand, when the drive switch 18 is in the OFF state, the control circuit 36 proceeds to S2420.

In the chain saw 1 configured as described above, the motor drive unit 30 determines whether it is in a loaded state where the operator has started working or in a no-loaded state where the operator is not working. The protection condition is that the no-load time Tnl during which the motor 10 is driven in the no-load state is equal to or greater than a preset temperature protection determination value TH15. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S2420, S2460 and S2470 correspond to the processing of the control circuit, and S2610, S2430 to S2450 and S2480 correspond to the processing of the load determination section.

(16th embodiment)
A sixteenth embodiment of the present disclosure will be described below with reference to the drawings. Note that in the fifteenth embodiment, portions different from the fourteenth embodiment will be described. The same code|symbol is attached|subjected about a common structure.

The chainsaw 1 of the sixteenth embodiment differs from that of the fourteenth embodiment in that the temperature protection determination process is changed.
The temperature protection determination process of the sixteenth embodiment differs from that of the fourteenth embodiment in that S2710 and S2720 are executed instead of S2410.

That is, as shown in FIG. 22, when the temperature protection determination process of the fifteenth embodiment is executed, the control circuit 36 first determines in S2710 whether or not the motor 10 is being driven. Here, if the motor 10 is being driven, the control circuit 36 proceeds to S2430.

On the other hand, if the motor 10 is not being driven, the control circuit 36 proceeds to S2510.
When the process of S2520 ends, the control circuit 36 determines in S2720 whether or not the drive switch 18 is on. Here, if the drive switch 18 is not in the ON state, the control circuit 36 proceeds to S2530. On the other hand, when the drive switch 18 is in the ON state, the control circuit 36 once terminates the temperature protection determination process.

In the chain saw 1 configured as described above, the motor drive unit 30 determines whether it is in a loaded state where the operator has started working or in a no-loaded state where the operator is not working. The protection condition is that the no-load time Tnl during which the motor 10 is driven in the no-load state is equal to or greater than a preset temperature protection determination value TH15. In this way, the chain saw 1 can suppress the temperature rise of the nut 7 without having a temperature sensor that directly detects the nut temperature, so that the configuration of the chain saw 1 can be simplified.

In the embodiment described above, S10 to S60, S2460, S2470, S2530, S2540, and S2720 correspond to the processing of the control circuit, and S2710, S2430 to S2450, S2510, and S2520 correspond to the processing of the load determination section.

An embodiment of the present disclosure has been described above, but the present disclosure is not limited to the above embodiment, and can be implemented in various modifications.
For example, in the above embodiment, in S320 of the initial temperature calculation process, the current estimated temperature Tnow is initialized with the controller temperature Tcnt. may

A plurality of functions possessed by one component in the above embodiment may be implemented by a plurality of components, or a function possessed by one component may be implemented by a plurality of components. Also, a plurality of functions possessed by a plurality of components may be realized by a single component, or a function realized by a plurality of components may be realized by a single component. Also, part of the configuration of the above embodiment may be omitted. Also, at least part of the configuration of the above embodiment may be added or replaced with respect to the configuration of the other above embodiment.

In addition to the chain saw 1 described above, a system having the chain saw 1 as a component, a program for causing a computer to function as the chain saw 1, a non-transitional physical recording medium such as a semiconductor memory in which the program is recorded, a protection control method, etc. , the disclosure may be implemented in various forms.

DESCRIPTION OF SYMBOLS 1... Chain saw, 3... Saw chain, 4... Guide bar, 5... Main body, 7... Nut, 10... Motor, 36... Control circuit

Claims (8)

a main body housing therein a driving source configured to generate a driving force by rotating;
a guide bar fixed to the main body so as to protrude from the main body;
a saw chain attached along the outer periphery of the guide bar and configured to rotate along the outer periphery of the guide bar by the driving force generated by the drive source;
a fixing member disposed outside the main body and fixing the guide bar to the main body;
a stop process for stopping the rotation of the drive source when a protection condition indicating that a member temperature, which is the temperature of the fixed member, is equal to or higher than a preset protection temperature is met; and a stop process in which the protection condition is not met. a control circuit configured to perform either one of a reduction process for reducing the rotation of the drive source more than the case ,
The control circuit includes a temperature estimator configured to estimate the member temperature based on the rotation speed of the drive source,
The chain saw , wherein the protection condition is that the temperature of the member estimated by the temperature estimation unit is equal to or higher than the protection temperature . a main body housing therein a driving source configured to generate a driving force by rotating;
a guide bar fixed to the main body so as to protrude from the main body;
a saw chain attached along the outer periphery of the guide bar and configured to rotate along the outer periphery of the guide bar by the driving force generated by the drive source;
a fixing member disposed outside the main body and fixing the guide bar to the main body;
a stop process for stopping the rotation of the drive source when a protection condition indicating that a member temperature, which is the temperature of the fixed member, is equal to or higher than a preset protection temperature is met; and a stop process in which the protection condition is not met. a control circuit configured to perform either one of a reduction process for reducing the rotation of the driving source more than the case
with
The control circuit includes a calorific value estimator configured to estimate a member calorific value, which is the calorific value of the fixed member, based on the rotational speed of the drive source,
The chain saw, wherein the protection condition is that the member heat generation amount estimated by the heat generation amount estimation unit is equal to or greater than a preset protection heat generation amount. a main body housing therein a driving source configured to generate a driving force by rotating;
a guide bar fixed to the main body so as to protrude from the main body;
a saw chain attached along the outer periphery of the guide bar and configured to rotate along the outer periphery of the guide bar by the driving force generated by the drive source;
a fixing member disposed outside the main body and fixing the guide bar to the main body;
a stop process for stopping the rotation of the drive source when a protection condition indicating that a member temperature, which is the temperature of the fixed member, is equal to or higher than a preset protection temperature is met; and a stop process in which the protection condition is not met. a control circuit configured to perform either one of a reduction process for reducing the rotation of the driving source more than the case
with
The control circuit includes a load determination unit configured to determine whether the worker is in a loaded state where the worker has started work or a no-load state where the worker is not working,
The chain saw, wherein the protection condition is that the no-load drive time during which the drive source is driven in the no-load state is equal to or longer than a preset no-load protection time. a main body housing therein a driving source configured to generate a driving force by rotating;
a guide bar fixed to the main body so as to protrude from the main body;
a saw chain attached along the outer periphery of the guide bar and configured to rotate along the outer periphery of the guide bar by the driving force generated by the drive source;
a fixing member disposed outside the main body and fixing the guide bar to the main body;
a stop process for stopping the rotation of the drive source when a protection condition indicating that a member temperature, which is the temperature of the fixed member, is equal to or higher than a preset protection temperature is met; and a stop process in which the protection condition is not met. a control circuit configured to perform either one of a reduction process for reducing the rotation of the driving source more than the case
with
The control circuit includes a time measuring unit configured to measure an operation time during which a driving operation unit operated by a user to generate the driving force in the driving source is operated,
The protection condition is that the operating time measured by the time measuring unit is equal to or longer than a preset operating protection time. The chain saw according to claim 1 ,
The control circuit includes a level detection unit configured to detect a tension level indicating a tension level of the saw chain with respect to the guide bar,
The temperature estimating unit estimates the temperature of the member according to the tension level so that the higher the tension of the saw chain, the higher the temperature of the member. The chain saw according to claim 2 ,
The control circuit includes a level detection unit configured to detect a tension level indicating a tension level of the saw chain with respect to the guide bar,
The calorific value estimating unit estimates the member calorific value according to the tension level so that the member calorific value increases as the tension of the saw chain increases. The chain saw according to claim 1 ,
a temperature dependent holding unit configured to hold power supply to the control circuit when the member temperature estimated by the temperature estimating unit exceeds a preset temperature holding judgment value; A chainsaw ready. The chain saw according to claim 2 ,
a calorific value configured to hold power supply to the control circuit when the member calorific value estimated by the calorific value estimating unit exceeds a preset calorific value retention determination value; A chainsaw with a dependent holding part.

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