Work machine

Abstract

To provide a work machine with improved convenience.SOLUTION: A hammer drill 10 includes a motor 26, an impact force applicator 34, a rotational force applicator 54, a trigger 72, an on-lock button 78, and a controller 90. The hammer drill 10 is operable in a plurality of switchable modes, including a first mode and a second mode. When the first mode is selected and the on-lock button 78 is not operated, the controller 90 executes a first control that drives the motor 26 when the trigger 72 is at a first position P1 and stops the motor 26 when the trigger 72 is at a second position P2. When the first mode is selected and the on-lock button 78 is operated, the controller 90 executes a second control that continues driving the motor 26. When the second mode is selected and the on-lock button 78 is operated, the controller 90 executes a third control that is different from both the first control and the second control.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a work machine. [Background technology]

[0002] The hammer drill of Patent Document 1 includes a motor, a trigger lever, an on-lock button, a sensor, and a controller. The controller executes on-lock control when the on-lock button is operated in hammer mode, but does not execute on-lock control in hammer drill mode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2016 / 121458 Summary of the Invention [Problem to be solved by the invention]

[0004] In the hammer drill of Patent Document 1, the on-lock button is used only in hammer mode, and the convenience of having the on-lock button is low.

[0005] An object of the present invention is to provide a work machine with improved convenience. [Means for solving the problem]

[0006] A work machine according to one embodiment is operable in a plurality of switchable modes, including a first mode in which only an impact force is applied to the tool bit, and a second mode in which an impact force and a rotational force are applied to the tool bit. The work machine includes a motor, an impact force application unit, a rotational force application unit, a first operating unit, a second operating unit, and a control unit. The impact force application unit is capable of applying an impact force to the tool bit in a direction along the longitudinal axis of the tool bit upon receiving the driving force of the motor. The rotational force application unit is capable of applying a rotational force to the tool bit about the longitudinal axis upon receiving the driving force of the motor. The first operating unit and the second operating unit are operated by an operator.

[0007] The control unit controls the driving of the motor. When the first mode is selected and the second operating unit is not operated, the control unit executes first control to drive the motor when the first operating unit is located in a first position and to stop the motor when the first operating unit is located in a second position.

[0008] When the first mode is selected and the second operation unit is operated, the control unit executes a second control for continuing to drive the motor even when the first operation unit is located at the second position. When the second mode is selected and the second operation unit is operated, the control unit executes a third control different from both the first control and the second control. [Effects of the Invention]

[0009] According to the present invention, the convenience of the work machine can be improved. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an explanatory view showing an internal configuration of a hammer drill according to a first embodiment. [Figure 2] 2 is a plan view of the hammer drill of FIG. 1 in a state where a second mode is set, as viewed from above. FIG. [Figure 3] 2 is a plan view of the hammer drill of FIG. 1 in a state where a first mode is set, as viewed from above. FIG. [Figure 4] FIG. 4 is an explanatory view showing the internal configuration of the hammer drill of FIG. 3. [Figure 5] 2 is a circuit block diagram showing each component of the hammer drill of FIG. 1. FIG. [Figure 6] 2 is a table summarizing the selected mode, trigger state, on-lock button state, motor drive state, and control state of the hammer drill of FIG. 1. [Figure 7] 2 is a flowchart showing each process executed by the hammer drill of FIG. 1. [Figure 8] FIG. 6 is a circuit block diagram showing each configuration of a hammer drill according to a second embodiment. [Figure 9] 9 is a flowchart showing each process executed by the hammer drill of FIG. 8. [Figure 10] FIG. 10 is a circuit block diagram showing each configuration of a hammer drill according to a third embodiment. [Figure 11] 11 is an explanatory view of a part of the hammer drill of FIG. 10 as seen from behind. FIG. [Figure 12] 11 is an explanatory diagram showing the positional relationship of a trigger, an on-lock button, and a speed change button in the hammer drill of FIG. 10. [Figure 13] 11 is a table summarizing the selection mode, trigger state, on-lock button state, motor drive state, control state, and rotation speed switching by speed change button operation of the hammer drill of FIG. 10. [Figure 14] 11 is a flowchart showing each process executed by the hammer drill of FIG. 10. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, working machines according to first, second, and third embodiments and modifications of the present invention will be described in detail with reference to the drawings. In all drawings referred to in describing the embodiments and modifications, the same or substantially the same configurations and elements will be designated by the same reference numerals. Furthermore, once a configuration or element has been described, it will not be described again, as a general rule.

[0012] [Configuration of the first embodiment] FIG. 1 shows a hammer drill 10 as a work machine according to a first embodiment.

[0013] The hammer drill 10 includes a housing 12, a handle 21, a battery 24, a motor 26, an impact force applying unit 34, a rotational force applying unit 54, a trigger 72, a change lever 76, an on-lock button 78, a Hall IC 84, and a control unit 90. The hammer drill 10 also includes a drill bit D. The housing 12 and the handle 21 form the outer shell of the hammer drill 10.

[0014] The drill bit D is an example of a tool tip that operates by receiving a driving force from the motor 26. The drill bit D is detachably mounted on a tool holding portion 69, which will be described later. The hammer drill 10 can perform chipping, crushing, and drilling operations on a mating material G, such as concrete, by applying only an impact force or applying an impact force and a rotational force to the drill bit D.

[0015] When the drill bit D is attached to the tool holding portion 69, the direction along the central axis CA, which is the long axis of the drill bit D, is defined as the front-rear direction. Directions perpendicular to the front-rear direction are defined as the up-down direction and the left-right direction. The up-down direction and the left-right direction are perpendicular to each other. Note that the up-down direction, front-rear direction, and left-right direction are set merely for the convenience of explanation.

[0016] The hammer drill 10 can operate in a plurality of switchable modes, including a first mode in which only an impact force is applied to the drill bit D, causing the drill bit D to perform an impact motion, and a second mode in which an impact force and a rotational force are applied to the drill bit D, causing the drill bit D to perform a rotational impact motion. Note that while the drill bit D is locked to prevent rotation in the first mode, the hammer drill 10 may also have a third mode in which no rotational force is transmitted to the drill bit D, but the drill bit D is not locked either, allowing the drill bit D to be manually rotated.

[0017] <Housing> The housing 12 has a motor housing portion 14, a mechanism housing portion 16 located above the motor housing portion 14, and a cylinder housing portion 18 extending forward from the mechanism housing portion 16. The housing 12 supports a motor 26. A panel 15 is provided on the rear end surface of the motor housing portion 14. The panel 15 is provided with an indicator lamp 17 (FIG. 5). The indicator lamp 17 is made up of a plurality of LEDs (Light Emitting Diodes). By visually checking the number of lit LEDs for a setting item related to the control of the hammer drill 10, the operator can determine the setting content, setting level, etc. of the item.

[0018] <handle> The handle 21 is made up of a main handle 22 and a sub-handle 23. The main handle 22 is formed in a C-shape when viewed from the left and right. The main handle 22 is connected to the rear end of the motor housing portion 14 and the rear end of the mechanism housing portion 16. The sub-handle 23 extends leftward from the cylinder housing portion 18. The housing 12 and the handle 21 are integrally constructed.

[0019] <Battery> The battery 24 is detachably attached to the lower end of the main handle 22. The battery 24 is connected to a terminal (not shown) provided at the lower end of the main handle 22, thereby enabling power to be supplied to each part of the hammer drill 10.

[0020] <Motor> The motor 26 is accommodated in the motor accommodating portion 14. In other words, the motor 26 is supported by the housing 12. The motor 26 is, for example, a brushless motor. The motor 26 has a stator 27, a rotor 28 arranged inside the stator 27, and an output shaft 29 fixed to the rotor 28.

[0021] The output shaft 29 extends upward through the rotor 28. The output shaft 29 has a central axis CB. The central axis CB is perpendicular to the central axis CA of a cylinder 66 and a retainer sleeve 68, which will be described later. A pinion gear 32 is provided on the upper end of the output shaft 29.

[0022] <Impact force application section> The striking force applying portion 34 has a first drive shaft 36 , a piston 46 , a striker 48 , and a second hammer 52 .

[0023] The first drive shaft 36 is located rearward of the output shaft 29. The first drive shaft 36 extends in the vertical direction. A first gear 38 that meshes with the pinion gear 32 is provided on the first drive shaft 36. An eccentric pin 42 is provided on the upper portion of the first drive shaft 36. The eccentric pin 42 is connected to a piston 46 via a connecting rod 44.

[0024] The piston 46 and the striker 48 are housed in a cylinder 66 (described later) so as to be movable in the front-rear direction. The second hammer 52 is housed in a retainer sleeve 68 (described later) so as to be movable in the front-rear direction.

[0025] The second hammer 52 is provided so as to be able to reciprocate in the front-to-rear direction, straddling the cylinder 66 and the retainer sleeve 68. The piston 46, striker 48, and second hammer 52 are aligned in this order from the rear to the front of the cylinder 66. An air chamber 49 is provided in the cylinder 66 between the piston 46 and the striker 48.

[0026] The drill bit D is attached to the retainer sleeve 68 by being inserted into a tool holding portion 69, which will be described later. When the cylinder 66 and the retainer sleeve 68 rotate, the drill bit D rotates. When a striking force is transmitted from the second hammer 52 to the drill bit D, the drill bit D reciprocates back and forth within a predetermined range.

[0027] In this way, the impact force applying section 34 is able to apply an impact force to the drill bit D in a direction along the major axis (central axis CA) of the drill bit D (front-rear direction) by receiving the driving force of the motor 26.

[0028] <Rotational force applying section> The rotational force applying unit 54 has a second drive shaft 56, a bevel gear 58, a link gear 62, a clutch 64, a cylinder 66, and a retainer sleeve 68. The rotational force applying unit 54 receives the driving force of the motor 26 and is capable of applying a rotational force to the drill bit D about its major axis (central axis CA).

[0029] The cylinder 66 and the retainer sleeve 68 are each made of a cylindrical member. The cylinder 66 and the retainer sleeve 68 are housed in the cylinder housing portion 18. The cylinder 66 and the retainer sleeve 68 have the same center axis CA. A tool holding portion 69 is provided at the front of the retainer sleeve 68. The cylinder 66 and the retainer sleeve 68 are engaged so that they cannot rotate relative to each other. Therefore, when a rotational force is transmitted to the cylinder 66, the cylinder 66 and the retainer sleeve 68 rotate together about the center axis CA.

[0030] The second drive shaft 56 is located forward of the output shaft 29. The second drive shaft 56 extends in the vertical direction. A second gear 57 that meshes with the pinion gear 32 is provided on the second drive shaft 56. A bevel gear 58 is provided on the upper part of the second drive shaft 56. The bevel gear 58 meshes with a link gear 62 that is arranged around a cylinder 66.

[0031] The ring gear 62 is attached to the outer peripheral surface of the cylinder 66 via a slide bearing. The ring gear 62 is freely rotatable relative to the cylinder 66. In addition to the ring gear 62, a clutch 64 is provided on the outer peripheral surface of the cylinder 66. The clutch 64 is provided so as to be rotatable integrally with the cylinder 66. Furthermore, the clutch 64 is slidable in the front-to-rear direction relative to the cylinder 66.

[0032] The position of the clutch 64 in the front-to-rear direction is changed by a change lever 76, which will be described later. Specifically, the change lever 76 is connected to the clutch 64 via a link mechanism 65. When the change lever 76 is rotated, the link mechanism 65 slides the clutch 64 in the front-to-rear direction, thereby positioning the clutch 64 at one of the front end position, the intermediate position, and the rear end position.

[0033] <Trigger> The trigger 72 is an example of a first operating unit operated by an operator. The trigger 72 is provided in the front portion of the main handle 22 so as to be rotatable about a rotation axis K whose axial direction is in the left-right direction. The trigger 72 faces the rear end surface of the mechanism housing portion 16 in the front-rear direction. The trigger 72 is rotatable around the rotation axis K within a range from a first position P1 to a second position P2.

[0034] The first position P1 of the trigger 72 is the position of the trigger 72 when the operator operates the trigger 72. The second position P2 of the trigger 72 is the position of the trigger 72 when the operator does not operate the trigger 72.

[0035] A trigger switch 74 is provided inside the main handle 22, and is switched between an on state and an off state by operating a trigger 72. When an operator operates the trigger 72, the trigger 72 rotates from the second position P2 to the first position P1, and the motor 26 is activated. When the operator releases his or her finger from the trigger 72, and the trigger 72 rotates from the first position P1 to the second position P2 due to the pressing force of a spring (not shown), the motor 26 is stopped.

[0036] Thus, the first position P1 of the trigger 72 is an ON position for turning on the operation of the motor 26. The second position P2 of the trigger 72 is an OFF position for turning off the operation of the motor 26.

[0037] <Striking and rotating motion of the drill bit> The striking and rotating actions of the drill bit D will now be described. When the motor 26 is operated, the rotation of the output shaft 29 is transmitted to the first drive shaft 36 via the pinion gear 32 and the first gear 38. This causes the first drive shaft 36 to rotate. When the first drive shaft 36 rotates, the eccentric pin 42 rotates around the central axis of the first drive shaft 36. In other words, the eccentric pin 42 orbits around the central axis of the first drive shaft 36. As a result, the piston 46 reciprocates within the cylinder 66 in conjunction with the movement of the connecting rod 44.

[0038] When the piston 46 moves backward (away from) the striker 48, the pressure in the air chamber 49 decreases, causing the striker 48 to move backward. On the other hand, when the piston 46 moves forward (approaching) the striker 48, the pressure in the air chamber 49 increases, causing the striker 48 to move forward. The forward-moving striker 48 strikes the second hammer 52. The struck second hammer 52 strikes the drill bit D. In this way, striking force is transmitted to the drill bit D intermittently.

[0039] When the second drive shaft 56 rotates, the bevel gear 58 rotates, causing the ring gear 62 to rotate. The rotation of the ring gear 62 is transmitted to the cylinder 66 via the clutch 64, causing the cylinder 66 and the retainer sleeve 68 to rotate integrally. As a result, striking force is transmitted intermittently and rotational force is transmitted continuously to the drill bit D held in the retainer sleeve 68.

[0040] <Change lever> As shown in Figure 2, the change lever 76 is provided on the upper surface of the housing 12. The change lever 76 is rotatable around a central axis that extends in the vertical direction. When viewed from above, the change lever 76 has a circular outer shape. An indication mark M is provided on the upper surface of the change lever 76 to indicate the rotation position (mode setting position) of the change lever 76.

[0041] As shown in FIG. 1, a magnet 82 is provided at the lower end of a portion of the outer periphery of the change lever 76. The presence or absence of the magnet 82 is detected by a Hall IC 84, which will be described later. The change lever 76 is rotated by an operator to change the position of the clutch 64 in the front-to-rear direction. At this time, the position of the magnet 82 also changes. The change lever 76 is an example of a third operating unit that can switch between a first mode, a second mode, and a third mode, which will be described later. Note that the change lever 76 may be switchable between the first mode and the second mode, but not switchable to the third mode.

[0042] As shown in FIG. 3, when the direction mark M is at a position pointing forward, the control unit 90 (FIG. 1), which will be described later, sets the first mode.

[0043] As shown in Figure 4, when the indication mark M is in a position pointing forward, the clutch 64 is located at the rear end of its range of movement in the fore-and-aft direction. At this time, the clutch 64 is disengaged from the link gear 62 and engaged with the restricting member 67, restricting the rotation of the retainer sleeve 68. Meanwhile, the rotation of the first drive shaft 36 causes the piston 46 to reciprocate within the cylinder 66. In other words, the hammer drill 10 only performs an impact force application operation on the drill bit D.

[0044] As shown in FIG. 2, when the direction mark M is in a position pointing backward, the control unit 90 (FIG. 1) sets the second mode.

[0045] 1, when the indication mark M is in a position pointing rearward, the clutch 64 is located at the front end of its range of movement in the fore-and-aft direction. At this time, the clutch 64 is disengaged from the restricting member 67 and engaged with the link gear 62, causing the motor 26 to rotate the retainer sleeve 68. Furthermore, the rotation of the first drive shaft 36 causes the piston 46 to reciprocate within the cylinder 66. In other words, the hammer drill 10 applies a striking force and a rotational force to the drill bit D.

[0046] 2 is in a rotation position pointing left or right, the control unit 90 (FIG. 1) is set to the third mode. At this time, the clutch 64 is disengaged from both the restricting member 67 and the link gear 62, so the rotational force of the link gear 62 is not transmitted to the retainer sleeve 68. However, the operator can manually rotate the retainer sleeve 68 and the drill bit D by gripping and rotating the tool holding portion 69, etc.

[0047] <Operation mode of hammer drill> The hammer drill 10 shown in FIG. 1 has a first mode, a second mode, and a third mode as examples of operation modes of the hammer drill 10 (in other words, operation modes of the striking force imparting portion 34 and the rotational force imparting portion 54).

[0048] <<First Mode>> 3 and 4, the first mode is a striking mode (hammer mode) in which only the striking force applying portion 34 is driven. In the first mode, a striking force is transmitted to the drill bit D, but a rotational force is not transmitted.

[0049] The first state of the first mode refers to an unlocked state. In the unlocked state, the control unit 90 drives the motor 26 when the trigger 72 is in the first position P1, and stops driving the motor 26 when the trigger 72 is in the second position P2.

[0050] The second state of the first mode is an on-lock state, in which the control unit 90 continues to drive the motor 26 regardless of the position of the trigger 72.

[0051] <<Second mode>> 1 and 2, the second mode is an impact rotation mode (hammer drill mode) in which the impact force application unit 34 and the rotational force application unit 54 are driven. In the second mode, an impact force and a rotational force are transmitted to the drill bit D.

[0052] <<Third Mode>> The third mode is a neutral mode in which neither the impact force applying unit 34 nor the rotational force applying unit 54 is operated. In the third mode, no rotational force is transmitted to the drill bit D, but the rotation of the cylinder 66 is not restricted by the restricting member 67, so the operator can manually grasp and rotate the tool holding unit 69, etc. In other words, the operator can manually rotate the angle of the drill bit D in the rotational direction around the central axis CA.

[0053] <On-lock button> 1 is an example of a second operation unit operated by an operator. The on-lock button 78 can switch the state of a process executed by operating the trigger 72. The on-lock button 78 is, for example, a tactile switch that outputs a signal each time the on-lock button 78 is operated by an operator. The signal output from the on-lock button 78 is received by the control unit 90.

[0054] The on-lock button 78 is located at the upper and rear end of the handle 21. Furthermore, the on-lock button 78 is located rearward of the trigger 72. Since the on-lock button 78 and the trigger 72 are located close to each other in this manner, the operator can operate both the trigger 72 and the on-lock button 78 without changing the way he or she grips the handle 21. In other words, the operability of the hammer drill 10 is improved. The on-lock button 78 is provided with an illumination unit 79 that turns on and off according to predetermined conditions.

[0055] <Hall IC> 4, the Hall IC (Integrated Circuit) 84 is provided in the mechanism housing portion 16 at a position vertically facing the lower end of the change lever 76. The Hall IC 84 is an example of a sensor that detects the presence or absence of the magnet 82 of the change lever 76. The Hall IC 84 detects the magnetic strength of the magnet 82 (presence or absence of the magnet 82) and transmits a signal corresponding to the magnetic strength to the control portion 90.

[0056] When the operator rotates the change lever 76 of the hammer drill 10 to point the indication mark M to the left or right, the operator recognizes that the operation mode of the hammer drill 10 is the third mode.

[0057] On the other hand, the control unit 90 determines whether to operate in the first mode or the second mode using information on the detection result of the magnet 82 obtained by the Hall IC 84. If the detection result indicates that the magnet 82 is present, the control unit 90 sets the operation mode of the hammer drill 10 to the first mode. If the detection result indicates that the magnet 82 is not present, the control unit 90 sets the operation mode of the hammer drill 10 to the second mode.

[0058] <Control unit> 1 is a microcomputer including a processor and memory (not shown). The control unit 90 controls the driving of the motor 26. Specifically, the control unit 90 executes one of the first control, second control, and third control based on a combination of one of a plurality of modes including the first mode, second mode, and third mode described above and the operation of the trigger 72 and the on-lock button 78, respectively.

[0059] <<First Control>> When the first mode is selected and the on-lock button 78 is not operated, the control unit 90 executes a first control to drive the motor 26 when the trigger 72 is located at the first position P1 and to stop the motor 26 when the trigger 72 is located at the second position P2.

[0060] <<Second Control>> When the first mode is selected and the on-lock button 78 is operated, the control unit 90 executes a second control to continue driving the motor 26 (to set the motor 26 in an on-lock state) even when the trigger 72 is located at the second position P2. Note that if the on-lock button 78 is operated again while the control unit 90 is executing the second control, the control unit 90 stops the continuation of driving the motor 26. In other words, the on-lock state of the drive of the motor 26 is released.

[0061] <<Third Control>> When the second mode is selected and the on-lock button 78 is operated, the control unit 90 executes a third control that is different from both the first control and the second control. Note that the control unit 90 executes the third control when the trigger 72 is located at the second position P2 in the second mode. Also, in the second mode, the control unit 90 does not execute the third control when the trigger 72 is located at the first position P1.

[0062] Specifically, the control unit 90 can execute, as an example of the third control, control to switch the rotation direction of the motor 26 and control to switch the rotation mode of the motor 26.

[0063] The control for switching the rotation direction of the motor 26 is a control for switching the rotation direction of the motor 26 between forward and reverse rotation using the inverter circuit 25 (FIG. 5).

[0064] The control for switching the rotation mode of the motor 26 is control for switching between a first rotation mode and a second rotation mode. The first rotation mode is a mode in which the rotation speed of the motor 26 is increased at a first increase rate N1. The second rotation mode is a mode in which the rotation speed of the motor 26 is increased at a second increase rate N2 that is lower than the first increase rate N1. The increase rate of the rotation speed of the motor 26 corresponds to the rate of change of the number of rotations of the motor 26 per unit time. Note that the first increase rate N1 and the second increase rate N2 are not shown in the figures.

[0065] When the second increase rate N2 is set (selected), the rotation speed of the drill bit D increases more slowly when the trigger 72 is turned on, compared to when the first increase rate N1 is set. This makes it less likely that the position of the drill bit D will deviate from the target position of the mating material G.

[0066] The hammer drill 10 can be summarized as follows: The hammer drill 10 can select either a first mode or a second mode, which differ in the operation of the drill bit D. The hammer drill 10 includes a motor 26, a drill bit D driven by the motor 26, a trigger 72 and an on-lock button 78 operated by an operator, and a control unit 90 that controls the operation of the motor 26.

[0067] When the first mode is selected and the trigger 72 is operated, the control unit 90 executes control of the basic operation of driving the motor 26. When the first mode is selected and the on-lock button 78 is operated, the control unit 90 executes control of switching whether or not the basic operation can be continued. When the second mode is selected and the trigger 72 is operated, the control unit 90 executes control other than the control of the basic operation. When the second mode is selected and the on-lock button 78 is operated, the control unit 90 executes control other than the control of the basic operation.

[0068] <Circuit block diagram> FIG. 5 shows a circuit block diagram of the hammer drill 10. The housing 12 includes a main circuit unit 20. The main circuit unit 20 includes an indicator lamp 17, an inverter circuit 25, a motor 26, a power supply circuit 40, a trigger switch 74, an on-lock button 78, a Hall IC 84, a control unit 90, terminals T1 and T2. The battery 24 includes terminals T3 and T4. Terminal T3 contacts terminal T1. Terminal T4 contacts terminal T2. This allows power to be supplied from the battery 24 to each component of the main circuit unit 20.

[0069] The control unit 90 is supplied with power from the power supply circuit 40. The control unit 90 controls the operation or stop of the inverter circuit 25 based on signals sent from the trigger switch 74, the on-lock button 78, and the Hall IC 84. The inverter circuit 25 supplies the power supplied from the battery 24 to the motor 26.

[0070] FIG. 6 summarizes the driving state of the motor 26 (FIG. 1) and the control (control state) executed by the control unit 90 when the trigger 72 (FIG. 1) is turned on or off and the on-lock button 78 (FIG. 1) is turned on or off in each selected mode.

[0071] [Operation of the first embodiment] Each process in the hammer drill 10 shown in Fig. 1 will be described with reference to Fig. 7. Note that for each component of the hammer drill 10, reference will be made to Figs. 1 to 5, and individual figure numbers will be omitted. Each process shown in Fig. 7 is performed by the processor in the control unit 90 reading a processing program from memory, expanding the program in a portion of the memory, and executing the program.

[0072] In step S10, the control unit 90 detects the mode of the hammer drill 10. If the detection result from the Hall IC 84 indicates that the magnet 82 is not present, the control unit 90 sets the operation mode to the first mode. Note that, although the first mode is described here, the operation mode may also be set to the third mode. Furthermore, if the detection result from the Hall IC 84 indicates that the magnet 82 is present, the control unit 90 sets the operation mode to the second mode. Then, the process proceeds to step S12.

[0073] In step S12, the control unit 90 determines whether the set mode is the first mode. If it is the first mode (S12: YES), the process proceeds to step S14. If it is not, that is, if it is the second mode (S12: NO), the process proceeds to step S32.

[0074] In step S14, the control unit 90 determines whether the trigger 72 is in a pulled state (on state) by receiving an on signal or an off signal from the trigger switch 74. If the trigger 72 is in an on state (S14: YES), the process proceeds to step S16. If not (S14: NO), the process proceeds to step S18.

[0075] In step S16, the control unit 90 drives the motor 26. In other words, it rotates the output shaft 29. Then, the process proceeds to step S20.

[0076] In step S18, the control unit 90 receives an ON signal or OFF signal from the on-lock button 78 and determines whether the on-lock button 78 has been operated (whether it is in the ON state or OFF state). If the on-lock button 78 has been operated (S18: YES), the process proceeds to step S12. If the on-lock button 78 has not been operated (S18: NO), the process proceeds to step S12. In other words, there is no difference in the control content whether the on-lock button 78 has been operated or not; in other words, operation of the on-lock button 78 is ignored.

[0077] In step S20, the control unit 90 determines whether the trigger 72 is in the ON state by receiving an ON signal or OFF signal from the trigger switch 74. If the trigger 72 is in the ON state (S20: YES), the process proceeds to step S22. If not (S20: NO), the process proceeds to step S30.

[0078] In step S22, the control unit 90 determines whether the on-lock button 78 has been operated (whether it is in the on state or the off state) by receiving an on signal or an off signal from the on-lock button 78. If the on-lock button 78 has been operated (S22: YES), the process proceeds to step S24. If the on-lock button 78 has not been operated (S22: NO), the process proceeds to step S20.

[0079] In step S24, the control unit 90 continues the driving state of the motor 26. In other words, the driving of the motor 26 is set to an on-lock state, and the process then proceeds to step S26.

[0080] In step S26, the control unit 90 determines whether the trigger 72 is in the ON state by receiving an ON signal or OFF signal from the trigger switch 74. If the trigger 72 is in the ON state (S26: YES), the process proceeds to step S28. If not (S26: NO), the process proceeds to step S28.

[0081] In step S28, the control unit 90 determines whether the on-lock button 78 has been operated (whether it is in the on state or the off state) by receiving an on signal or an off signal from the on-lock button 78. If the on-lock button 78 has been operated (S28: YES), the process proceeds to step S30. If the on-lock button 78 has not been operated (S28: NO), the process proceeds to step S26.

[0082] In step S30, the control unit 90 stops driving the motor 26. In other words, it stops the rotation of the output shaft 29. Then, the process proceeds to step S12.

[0083] In step S32, the control unit 90 determines whether the trigger 72 is in a pulled state (on state) by receiving an on signal or an off signal from the trigger switch 74. If the trigger 72 is in an on state (S32: YES), the process proceeds to step S34. If not (S32: NO), the process proceeds to step S44.

[0084] In step S34, the control unit 90 drives the motor 26. Then, the process proceeds to step S36.

[0085] In step S36, the control unit 90 determines whether the trigger 72 is in a pulled state (ON state) by receiving an ON signal or OFF signal from the trigger switch 74. If the trigger 72 is in an ON state (S36: YES), the process proceeds to step S38. If not (S36: NO), the process proceeds to step S40.

[0086] In step S38, the control unit 90 receives an ON signal or OFF signal from the on-lock button 78 and determines whether the on-lock button 78 has been operated (whether it is in the ON state or OFF state). If the on-lock button 78 has been operated (S38: YES), the process proceeds to step S36. If the on-lock button 78 has not been operated (S38: NO), the process proceeds to step S36. In other words, there is no difference in the control content whether the on-lock button 78 has been operated or not; in other words, operation of the on-lock button 78 is ignored.

[0087] In step S40, the control unit 90 stops driving the motor 26. Then, the process proceeds to step S12.

[0088] In step S44, the control unit 90 determines whether the on-lock button 78 has been operated by receiving an ON signal or OFF signal from the on-lock button 78. If the on-lock button 78 has been operated (S44: YES), the process proceeds to step S46. If the on-lock button 78 has not been operated (S44: NO), the process proceeds to step S12.

[0089] In step S46, the control unit 90 switches the rotation mode of the output shaft 29 (motor 26) from the first rotation mode to the second rotation mode. In other words, the control unit 90 sets a second increase rate N2 lower than the first increase rate N1 as the increase rate of the rotation speed of the motor 26. Then, the process proceeds to step S12.

[0090] Furthermore, if during the above processing, another operation is performed, such as switching the change lever 76 to the third mode (neutral mode), and the control unit 90 receives a signal indicating that processing has ended, the operation of the motor 26 is stopped and the program ends.

[0091] As described above, in the hammer drill 10, when the first mode is selected by the change lever 76 and the on-lock button 78 is not operated, the control unit 90 drives the motor 26 when the trigger 72 is in the first position P1 (on position). Furthermore, the control unit 90 stops the motor 26 when the trigger 72 is in the second position P2 (off position). In this way, the control unit 90 executes the first control.

[0092] When the first mode is selected and the on-lock button 78 is operated, the control unit 90 executes a second control to continue driving the motor 26 even when the trigger 72 is located at the second position P2.

[0093] When the second mode is selected by the change lever 76 and the on-lock button 78 is operated, the control unit 90 executes a third control that is different from both the first control and the second control. In this way, the on-lock button 78, which is used to switch between driving and non-driving of the motor 26 in the first mode, is effectively used as an operating unit for executing the third control in the second mode, thereby improving the convenience of the hammer drill 10.

[0094] The hammer drill 10 is provided with a change lever 76, which allows the operator to freely switch between the first mode and the second mode.

[0095] The hammer drill 10 has a third mode (neutral mode) in which the motor 26 is not driven. The operator can switch between the first mode, the second mode, and the third mode by operating the change lever 76. This allows the angle of the drill bit D in the rotational direction about the central axis CA to be optimized when using the hammer drill 10 in the first mode by changing the angle of the drill bit D in the third mode before using the hammer drill 10 in the first mode (hammer mode).

[0096] In the hammer drill 10, the rotation direction of the motor 26 can be switched by operating the on-lock button 78. As a result, if the drill bit D gets caught on the mating material G during rotation, reversing the rotation direction makes it easier to remove the drill bit D from the mating material G.

[0097] In the hammer drill 10, the control unit 90 switches between the first rotation mode and the second rotation mode as a third control. When the second rotation mode is selected, the rotation speed of the drill bit D increases more gradually than in the first rotation mode when the drill bit D is pressed against the mating workpiece G and then operation is started. This prevents the drill bit D from suddenly rotating at a high speed, making it less likely that the position of the drill bit D will deviate from the target position of the mating workpiece G.

[0098] In the hammer drill 10, in the second mode (hammer drill mode), if the on-lock button 78 is operated when the trigger 72 is in the second position P2 (off state), the third control is executed. In other words, since the third control is executed when the motor 26 is stopped, it becomes easy to change various settings of the hammer drill 10 using the on-lock button 78.

[0099] On the other hand, even in the second mode, the third control is not executed when the trigger 72 is located at the first position P1. Furthermore, in the first mode, the second control is executed when the on-lock button 78 is operated while the trigger 72 is located at the first position P1, but the second control is not executed even when the on-lock button 78 is operated while the trigger 72 is located at the first position P1. In other words, the second control is executed only when the trigger 72 is located at the first position P1, and the third control is executed only when the trigger 72 is located at the second position P2. This makes it less likely that an operator will confuse an operation intended for the second control with an operation intended for the third control. However, in the second mode, the third control may be executed when the on-lock button 78 is operated even when the trigger 72 is located at the first position P1.

[0100] <Summary> In the hammer drill 10, when the first mode is selected and the trigger 72 is operated, the control unit 90 controls the basic operation of driving the motor 26. When the first mode is selected and the on-lock button 78 is operated, the control unit 90 controls whether or not the basic operation can be continued. When the second mode is selected and the trigger 72 is operated, the control unit 90 controls the basic operation. When the second mode is selected and the on-lock button 78 is operated, the control unit 90 controls other controls (auxiliary functions) that are different from the control of the basic operation.

[0101] In this way, the on-lock button 78, which is used to switch whether or not to continue the basic operation in the first mode, is effectively used as an operating unit for executing other controls different from the basic operation in the second mode, thereby improving the convenience of the hammer drill 10.

[0102] [Configuration of the second embodiment] A hammer drill 100 as a work machine according to the second embodiment will be described. Note that the same or similar components as those of the hammer drill 10 (FIG. 1) of the first embodiment will be denoted by the same reference numerals and description thereof will be omitted.

[0103] 8 shows a circuit block diagram of the hammer drill 100. The hammer drill 100 differs from the hammer drill 10 (FIG. 5) in that an acceleration sensor 102 is added.

[0104] The acceleration sensor 102 is provided in the housing 12. The acceleration sensor 102 detects the rotational state of the housing 12 in the circumferential direction about the central axis CA of the hammer drill 100 (FIG. 1).

[0105] In the second mode (hammer drill mode), when the on-lock button 78 is operated while the trigger 72 (FIG. 1) is located at the second position P2 (FIG. 1), the control unit 90 executes a third control. The third control is a control for switching between execution and non-execution of a forced stop mode, which stops the driving of the motor 26 when the acceleration sensor 102 detects that the housing 12 has rotated in the circumferential direction about the longitudinal axis of the drill bit D (FIG. 1). Note that even in the second mode, when the trigger 72 is located at the first position P1, the third control is not executed even if the on-lock button 78 is operated.

[0106] A plurality of third controls are set in the control unit 90 of the hammer drill 100. The plurality of third controls include a control for changing the rotation speed of the motor 26, a control for switching between the first and second rotation modes, a control for switching whether or not the rotation of the motor 26 can continue, a control for forcibly stopping the rotation of the motor 26, and a control for displaying the amount of power that can be supplied to the motor 26. Note that the control for switching whether or not the rotation of the motor 26 can continue is the same as in the first embodiment, and therefore a description thereof will be omitted.

[0107] [Operation of the second embodiment] A portion of the operational processing of the hammer drill 100 shown in Figure 8 will be described with reference to Figure 9. For each component of the hammer drill 10, reference will be made to Figures 1 to 5 and Figure 8, and individual figure numbers will not be given. Each process shown in Figure 9 is performed by the processor in the control unit 90 reading a processing program from memory, expanding the program in part of the memory, and executing the program.

[0108] Note that steps S14 to S30 (FIG. 7) in the first embodiment are executed in the same manner, and therefore illustrations and explanations thereof are omitted. Also, step S44 (FIG. 7) in the first embodiment is replaced with step S45.

[0109] 9, after the second mode (hammer drill mode) is set in steps S10 and S12, the control unit 90 determines in step S32 that the trigger 72 is in the OFF state. In this case, the process proceeds to step S45.

[0110] In step S45, the control unit 90 determines whether the on-lock button 78 has been operated only once by counting the number of times an operation signal has been received from the on-lock button 78. If the on-lock button 78 has been operated once (S45: YES), the process proceeds to step S46. If the on-lock button 78 has been operated two or more times (S45: NO), the process proceeds to step S50.

[0111] In step S50, the control unit 90 determines whether the on-lock button 78 has been operated twice. If the on-lock button 78 has been operated twice (S50: YES), the process proceeds to step S52. If the on-lock button 78 has been operated three or more times (S50: NO), the process proceeds to step S54.

[0112] In step S52, the control unit 90 changes the rate of increase in the rotation speed of the motor 26 from the first increase rate N1 to the second increase rate N2. That is, the control unit 90 switches from the first rotation mode to the second rotation mode. Then, the process proceeds to step S12.

[0113] In step S54, the control unit 90 determines whether the on-lock button 78 has been operated three times. If the on-lock button 78 has been operated three times (S54: YES), the process proceeds to step S56. If the on-lock button 78 has been operated four or more times (S54: NO), the process proceeds to step S58.

[0114] In step S56, the control unit 90 sets the forced stop mode. The forced stop mode is a mode in which the rotation of the motor 26 is forcibly stopped when the acceleration sensor 102 detects an acceleration equal to or greater than a threshold value. Note that in step S56, the motor 26 is not operating, so the forced stop mode is not executed. The control unit 90 simply sets the forced stop mode. Then, the process proceeds to step S12.

[0115] In step S58, the control unit 90 determines whether the on-lock button 78 has been operated four times. If the on-lock button 78 has been operated four times (S58: YES), the control unit 90 proceeds to step S60. If the on-lock button 78 has been operated five times or more (S58: NO), the control unit 90 proceeds to step S12.

[0116] In step S60, the control unit 90 acquires information about the amount of power stored in the battery 24 via the power supply circuit 40 and displays the amount of power that can be supplied to the motor 26 on the indicator lamp 17. For example, the control unit 90 allows the operator to recognize the amount of power by the number of lit LEDs on the indicator lamp 17. Then, the process proceeds to step S12. Note that the conditions for terminating the program are the same as those in the first embodiment, and therefore will not be described here.

[0117] As described above, in the second mode of the hammer drill 100, when the acceleration sensor 102 detects that the housing 12 has rotated in the circumferential direction about the central axis CA, the control unit 90 forcibly stops the rotation of the motor 26. This locks the rotation while the drill bit D is entering the mating material G, thereby preventing the housing 12 of the hammer drill 100 from vibrating (recoil).

[0118] In the hammer drill 100, a plurality of third controls can be set in the control unit 90. For example, at least one of the following can be performed: a control to change the rotation speed of the motor 26, a control to switch whether or not the rotation of the motor 26 can continue, a control to forcibly stop the rotation of the motor 26, and a control to display the amount of power that can be supplied to the motor 26.

[0119] [Configuration of the third embodiment] A hammer drill 110 as a work machine according to the third embodiment will be described. Note that the same or similar components as those of the hammer drill 10 (FIG. 5) and the hammer drill 100 (FIG. 8) of the first and second embodiments will be denoted by the same reference numerals and will not be described again.

[0120] Figure 10 shows a circuit block diagram of the hammer drill 110. The hammer drill 110 differs from the hammer drill 10 (Figure 5) in that a speed change button 112 is added.

[0121] As shown in FIG. 11 , the speed change button 112 is provided on the panel 15 together with the indicator lamp 17, for example. The rotation speed of the motor 26 ( FIG. 10 ) is changed depending on the number of times the speed change button 112 is operated by the operator. In other words, the speed change button 112 is an example of a fourth operating unit. In the hammer drill 110, the rotation speed of the motor 26 can be changed as a third control. Note that, for example, the control unit 90 ( FIG. 10 ) can switch the rotation speed of the motor 26 as a third control when the speed change button 112 is operated in each of the first mode and the second mode.

[0122] As shown in FIG. 12 , point A represents the position on the front surface of trigger 72 that is most likely to receive force from the operator's hand. Point B represents the center position of on-lock button 78. Point C represents the center position of gearshift button 112. Here, length L1 of line segment AB is shorter than length L2 of line segment AC. In other words, on-lock button 78 is located closer to trigger 72 than gearshift button 112.

[0123] 13 summarizes the drive state of the motor 26 (FIG. 1) and the control (control state) executed by the control unit 90 when the trigger 72 (FIG. 1) is turned on or off and the on-lock button 78 (FIG. 1) is turned on or off in each selected mode. Furthermore, FIG. 13 shows a case where the rotation speed is switched by turning on the speed change button 112 (FIG. 10) in each selected mode.

[0124] [Operation of the third embodiment] A portion of the operational processing of the hammer drill 110 shown in Figure 10 will be described with reference to Figure 14. For each component of the hammer drill 110, reference will be made to Figures 1 to 5 and Figure 10, and individual figure numbers will not be given. Each process shown in Figure 14 is performed by the processor in the control unit 90 reading a processing program from memory, expanding it in a portion of the memory, and executing it. Note that a description of steps that are the same as those in the first and second embodiments will be omitted, and only steps that are different from those in the first and second embodiments will be described.

[0125] After the first mode (hammer mode) is set in steps S10 and S12, if it is determined in step S14 that the trigger 72 is in the OFF state, the process proceeds to step S62.

[0126] In step S62, the control unit 90 determines whether the gear shift button 112 has been operated (whether it is in the ON or OFF state) by receiving an ON signal or OFF signal from the gear shift button 112. If the gear shift button 112 has been operated (S62: YES), the process proceeds to step S64. If the gear shift button 112 has not been operated (S62: NO), the process proceeds to step S12.

[0127] In step S64, the control unit 90 switches the rotation number (rotation speed) of the motor 26 from low speed to high speed, or from high speed to low speed, and then proceeds to step S12.

[0128] When the second mode is set and it is determined in step S32 that the trigger 72 is in the OFF state, the process proceeds to step S68.

[0129] In step S68, the control unit 90 determines whether the gear shift button 112 has been operated (whether it is in the ON or OFF state) by receiving an ON signal or OFF signal from the gear shift button 112. If the gear shift button 112 has been operated (S68: YES), the process proceeds to step S70. If the gear shift button 112 has not been operated (S68: NO), the process proceeds to step S12.

[0130] In step S70, as an example of a third control, the control unit 90 switches the rotation number (rotation speed) of the motor 26 from low speed to high speed, or from high speed to low speed, and then proceeds to step S72.

[0131] In step S72, the control unit 90 determines whether the on-lock button 78 has been operated (whether it is in the on state or the off state) by receiving an on signal or an off signal from the on-lock button 78. If the on-lock button 78 has been operated (S72: YES), the process proceeds to step S74. If the on-lock button 78 has not been operated (S72: NO), the process proceeds to step S12.

[0132] In step S74, the control unit 90 switches the rotation mode of the motor 26 from the first rotation mode to the second rotation mode. In other words, the control unit 90 sets the rate of increase in the rotation speed of the motor 26 to a second increase rate N2 that is lower than the first increase rate N1. Then, the process proceeds to step S12. Note that the program termination conditions are the same as those in the first and second embodiments, and therefore will not be described here.

[0133] As described above, in the hammer drill 110, the rotation speed can be changed by operating the speed change button 112 not only in the second mode but also in the first mode, so that the third control can be performed in the first mode.

[0134] Furthermore, in the hammer drill 110, the on-lock button 78 is located closer to the trigger 72 than the speed change button 112, making it easier for the operator to operate the on-lock button 78, which is used more frequently than the speed change button 112.

[0135] [Modification of this embodiment] This embodiment is not limited to the first, second, and third embodiments described above, and it goes without saying that various modifications are possible without departing from the spirit of the present invention. Modifications of this embodiment will be described below.

[0136] The hammer drill 10 does not necessarily have to be provided with the change lever 76. For example, the first mode and the second mode may be switched depending on the number of times the on-lock button 78 is operated before the trigger 72 is operated. Furthermore, the third operating unit is not limited to the change lever 76, and may instead be, for example, a switch that can slide to three positions in the forward / backward or left / right directions, and the first mode, second mode, and third mode may be set at the three positions.

[0137] The hammer drill 10 does not necessarily have to have the third mode. In this case, the change lever 76 only needs to be able to switch between the first mode and the second mode.

[0138] The rotation mode of the motor 26 is not limited to the first increase rate N1 and the second increase rate N2, but may be set to three or more increase rates.

[0139] In the hammer drill 100, a gyro sensor may be used instead of the acceleration sensor 102 to detect the state of the hammer drill 100 and forcibly stop the motor 26. The third control of the hammer drill 100 may be any one of control to change the rotation speed of the motor 26, control to switch between continuing rotation of the motor 26 and not, control to forcibly stop rotation of the motor 26, and control to display the amount of power that can be supplied to the motor 26. Alternatively, any two or three of these auxiliary functions may be used.

[0140] The hammer drill 110 does not necessarily have to be provided with the speed change button 112. Also, the on-lock button 78 may be located farther from the trigger 72 than the speed change button 112. Alternatively, the length L1 and the length L2 may be equal to each other. [Explanation of symbols]

[0141] 10: Hammer drill, 12: Housing, 14: Motor housing, 15: Panel, 16: Mechanism housing, 17: Indicator lamp, 18: Cylinder housing, 20: Main circuit section, 21: Handle, 22: Main handle, 23: Sub-handle, 24: Battery, 25: Inverter circuit, 26: Motor, 27: Stator, 28: Rotor, 29: Output shaft, 32: Pinion gear, 34: Impact force applying section, 36: First drive shaft, 38: First gear, 40: Power supply circuit, 42: Eccentric pin, 44: Connecting rod, 46: Piston, 48: Striker, 49: Air chamber, 52: Second hammer, 54: Rotational force applying section, 56: Second drive shaft, 57: Second gear, 58: Bevel gear, 62: Link gear, 64: clutch, 65: link mechanism, 66: cylinder, 67: restricting member, 68: retainer sleeve, 69: tool holder, 72: trigger, 74: trigger switch, 76: change lever, 78: on-lock button, 79: lighting unit, 82: magnet, 84: hall IC, 90: control unit, 100: hammer drill, 102: acceleration sensor, 110: hammer drill, 112: speed change button, A: point, B: point, C: point, CA: central axis, CB: central axis, D: drill bit, G: mating material, K: rotating axis, M: indication mark, N1: first rise rate, N2: second rise rate, P1: first position, P2: second position, T1: terminal, T2: terminal, T3: terminal, T4: terminal

Claims

1. A work machine that can operate in a plurality of switchable modes including a first mode in which only an impact force is applied to the tool bit, and a second mode in which an impact force and a rotational force are applied to the tool bit, A motor; an impact force applying unit that receives a driving force of the motor and applies an impact force to the tool bit in a direction along the longitudinal axis of the tool bit; a rotational force applying unit that receives a driving force of the motor and applies a rotational force to the tool bit about the longitudinal axis; a first operating unit and a second operating unit operated by an operator; a control unit that controls the driving of the motor; Equipped with The control unit when the first mode is selected and the second operation unit is not operated, a first control is executed to drive the motor when the first operation unit is located at a first position and to stop the motor when the first operation unit is located at a second position; When the first mode is selected and the second operation unit is operated, a second control is executed to continue driving the motor even when the first operation unit is located at the second position; When the second mode is selected and the second operation unit is operated, a third control different from both the first control and the second control is executed.

2. a third operation unit capable of switching between the first mode and the second mode is provided; The work machine according to claim 1 .

3. The third control is a control for switching the rotation direction of the motor. The work machine according to claim 1 .

4. the third control is control for switching between a first rotation mode in which the rotation speed of the motor is increased at a first increase rate and a second rotation mode in which the rotation speed of the motor is increased at a second increase rate that is lower than the first increase rate; The work machine according to claim 1 .

5. a housing for supporting the motor; the third control is control for switching whether or not to execute a forced stop mode, which stops driving of the motor when it is detected that the housing has rotated in a circumferential direction around the major axis of the tool bit; The work machine according to claim 1 .

6. the control unit, in the second mode, executes the third control when the second operation unit is operated while the first operation unit is located at the second position, and does not execute the third control even when the second operation unit is operated while the first operation unit is located at the first position. The work machine according to claim 1 .

7. the control unit, in the first mode, executes the second control when the second operation unit is operated while the first operation unit is located at the first position, and does not execute the second control when the second operation unit is operated while the first operation unit is located at the second position; The work machine according to claim 6.

8. the third control includes at least one of control for changing the rotation speed of the motor, control for switching whether or not the rotation of the motor can be continued, control for forcibly stopping the rotation of the motor, and control for displaying the amount of power that can be supplied to the motor. The work machine according to claim 7.

9. a fourth operating unit is provided, When the fourth operation unit is operated in the first mode, the control unit executes the third control. The work machine according to claim 1 .

10. the second operating unit is located closer to the first operating unit than the fourth operating unit; The work machine according to claim 9.

11. A work machine capable of selecting either a first mode or a second mode in which the operation of the tool bit differs, A motor; the tool bit that operates by receiving the driving force of the motor; a first operating unit and a second operating unit operated by an operator; a control unit that controls the driving of the motor; Equipped with The control unit When the first mode is selected and the first operation unit is operated, control of a basic operation of driving the motor is executed; When the first mode is selected and the second operation unit is operated, a control is executed to switch whether or not the basic operation can be continued; When the second mode is selected and the first operation unit is operated, the control of the basic operation is executed; When the second mode is selected and the second operation unit is operated, a control different from the control of the basic operation is executed.

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