Dust collection system for power tool

Abstract

To prevent operation of one of a power tool and a dust collection attachment from being stopped by battery exhaustion even if the power tool and the dust collection attachment respectively have batteries as power sources.SOLUTION: A dust collection system S for a power tool includes: a hammer drill 1 including a tool body side controller 13 which controls a tool body side DC motor 7 on the basis of, on / off operation of a switch 18, and a tool body side battery pack 26; and a dust collection attachment 60 including a duct 80, a dust box 65, a dust collection fan 94, a dust collection side DC motor 92, a dust collection side controller 96, and a dust collection side battery pack 101. When the dust collection attachment 60 is attached to the hammer drill 1, the tool body side controller 13 and the dust collection side controller 96 are electrically connected to each other. The dust collection side controller 96 uses the tool body side battery pack 26 singly to supply power to the tool body side DC motor 7 and the dust collection side DC motor 92 or uses the dust-collection side battery pack 101 singly to supply power to the tool body side DC motor 7 and the dust collection side DC motor 92.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a dust collection system for a power tool that includes a power tool and a dust collection attachment that is attached to the power tool to collect dust generated during use of the power tool. [Background technology]

[0002] When a workpiece such as concrete or stone is machined using a power tool such as a hammer drill, in order to prevent dust generated from the workpiece from scattering, a dust collection attachment including a suction section for sucking in dust, a dust collection section for storing the sucked dust, and a dust collection motor equipped with a fan for generating suction force is attached to the power tool to form a dust collection system for the power tool, as disclosed in Patent Document 1. The power tool and the dust collection attachment are each provided with a battery as a power source. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] European Patent Application No. 3222386 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional dust collection system for electric power tools, the electric power tool and the dust collection attachment are each powered by their own batteries, and therefore cannot be used if the remaining capacity of the battery drops to a level where the motor cannot be driven. As a result, if the battery runs out during work, the dust collection attachment stops working and only the electric power tool continues to work, or conversely, if the battery runs out, the electric power tool stops working and only the dust collection attachment continues to work, forcing the user to interrupt the work. This also reduces the efficiency of the battery usage.

[0005] Therefore, the present disclosure aims to provide a dust collection system for power tools that can prevent either one from stopping operation due to a dead battery, even if the power tool and the dust collection attachment each have a battery as a power source, and is expected to improve usability and battery usage efficiency. [Means for solving the problem]

[0006] In order to achieve the above object, the present disclosure provides a dust collection system for a power tool, the dust collection system including: a power tool having a switch that is turned ON / OFF; a main unit DC motor; a main unit controller that controls the main unit DC motor based on the ON / OFF operation of the switch; and a main unit battery; The dust collection attachment is attached to an electric power tool to collect dust generated when the electric power tool is used, and includes a suction section, a dust collection section that captures dust sucked through the suction section, a fan that generates suction force in the suction section, a dust collection side DC motor that rotates the fan, a dust collection side controller that controls the dust collection side DC motor, and a dust collection side battery. When the dust collection attachment is attached to the power tool, the main unit controller and the dust collection side controller are electrically connected, and the main unit battery and the dust collection side battery can be used independently by the main unit controller and the dust collection side controller as power sources for the main unit DC motor and the dust collection side DC motor, respectively. Effect of the Invention

[0007] According to the present disclosure, since both batteries can be used independently as power sources for both DC motors, even if the power tool and the dust collection attachment each have a battery as a power source, it is possible to prevent either one from stopping operation due to a dead battery. This improves usability. In addition, since the two batteries can be used in sequence and used up, the battery usage efficiency is also improved. [Brief description of the drawings]

[0008] [Figure 1]1 is a central vertical cross-sectional view of a dust collection system for a power tool; [Diagram 2] FIG. 2 is an enlarged view of the left half of the portion taken along line AA in FIG. [Diagram 3] 4 is a flowchart of an operation control of the power tool dust collection system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] In one embodiment of the present disclosure, the main unit side controller or the dust collection side controller may first use the main unit side battery solely as a power source for both DC motors, and then use the dust collection side battery solely as a power source for both DC motors. According to this configuration, the battery on the main unit side, which often has a larger capacity than the battery on the dust collection side, can be used preferentially. In one embodiment of the present disclosure, the main unit side controller or the dust collection side controller may first use the dust collection side battery solely as a power source for both DC motors, and then use the main unit side battery solely as a power source for both DC motors. According to this configuration, it is possible to suppress a decrease in the remaining capacity of the main battery and ensure a power source when the power tool is used alone. In one embodiment of the present disclosure, the machine side controller or the dust collection side controller may monitor the voltages of both batteries, and when the voltage value of one of the batteries that was previously used solely as a power source for both DC motors falls below a predetermined value at which both DC motors cannot be driven, the other battery may be used solely as a power source for both DC motors. According to this configuration, the two batteries can be used selectively depending on the voltage value, and operation stoppage due to one of the batteries running out can be effectively prevented. In one embodiment of the present disclosure, the dust collection side controller may determine a battery to be used solely as a power source for both DC motors, and when the voltage value of the dust collection side battery falls below a predetermined value, the main unit side controller may determine a battery to be used solely as a power source for both DC motors. According to this configuration, the use of the main unit side battery is reduced, while the operation control of the dust collection system can be continued even if the voltage value of the dust collection side battery drops.

[0010] In one embodiment of the present disclosure, the main unit side battery is attachable / detachable to a main unit side battery mounting section provided on the power tool, and the dust collection side battery is attachable / detachable to a dust collection side battery mounting section provided on the dust collection attachment, and the attachment / detachment structures of each battery on the main unit side battery mounting section and the dust collection side battery mounting section may be the same. According to this configuration, either battery can be attached to the power tool and the dust collection attachment as long as the batteries have the same rated voltage, improving usability. In one embodiment of the present disclosure, even if one of the two batteries is not attached to the battery attachment section, the main unit side controller or the dust collection side controller may use the other battery alone as a power source for both DC motors. According to this configuration, the entire system can be operated with just one battery attached, which leads to further improvement in usability. In one embodiment of the present disclosure, the main unit side controller or the dust collection side controller may be configured to drive the dust collection side DC motor first and then drive the main unit side DC motor in response to an ON operation of the switch. According to this configuration, the dust collection attachment can be operated first to generate suction force, so that dust can be reliably sucked up at the same time as work is performed with the power tool. In one embodiment of the present disclosure, the main unit side controller or the dust collection side controller may stop driving of the dust collection side DC motor after the main unit side DC motor has stopped driving in response to an OFF operation of the switch. According to this configuration, dust can be collected in the dust collecting section without remaining in the dust collection path after the operation of the power tool is stopped. In one embodiment of the present disclosure, a notification unit may be provided that notifies the user when the voltages of the main battery and the dust-collection battery become equal to or lower than a predetermined value. With this configuration, the worker can quickly take action such as replacing or charging both batteries. EXAMPLES

[0011] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a central vertical cross-sectional view showing an example of a dust collection system for a power tool (hereinafter simply referred to as a "dust collection system") S formed by attaching a dust collection attachment 60 to a hammer drill 1, which is an example of a power tool. First, the hammer drill 1 will be described. The hammer drill 1 has an inner housing 2, a motor housing 3, an upper outer housing 4, and a lower outer housing 5 as housings. The inner housing 2 houses a striking mechanism 6 extending in the front-to-rear direction. The motor housing 3 is connected to the lower part of the inner housing 2 and houses a main machine DC motor 7. The main machine DC motor 7 is held in the motor housing 3 with a rotating shaft 8 facing upward. An upper part of the rotating shaft 8 is supported by a bearing 9 held in the inner housing 2, and a pinion 10 provided at the upper end thereof protrudes into the inner housing 2. The upper outer housing 4 covers the outside of the inner housing 2 above the motor housing 3 .

[0012] The lower outer housing 5 has a front tubular portion 11 and a handle portion 12. The front tubular portion 11 covers the outside of the motor housing 3 from below. A machine-side controller 13 equipped with a control circuit board (not shown) is housed in the front tubular portion 11 at the rear of the motor housing 3 in a vertical direction. The machine-side controller 13 includes a CPU mounted on the control circuit board and a memory connected to the CPU, and controls the operation of the hammer drill 1 using these components. A front guide groove 14 is formed in the up-down direction at the center in the left-right direction on the front surface of the front tube portion 11. An upper locking recess 15 for mounting the dust collection attachment 60 is formed above and forward of the front guide groove 14. Horizontal locking recesses 16 for mounting the dust collection attachment 60 are formed on the left and right side surfaces of the front tube portion 11, as shown in Fig. 2. A pair of horizontal guide grooves 17, 17 extending upward from the lower end of the front tube portion 11 are formed in front of and behind the horizontal locking recess 16.

[0013] The handle portion 12 is connected to the lower portion of the front tubular portion 11 and extends rearward, and then extends upward to be connected to the rear end of the upper outer housing 4 . A switch 18 is provided inside the handle portion 12. The switch 18 has a plunger 19 protruding forward. A first machine-side lead wire 20 is connected to the switch 18. The first machine-side lead wire 20 is electrically connected to the machine-side controller 13, and an ON signal generated when the plunger 19 is pressed can be input to the machine-side controller 13. A switch lever 21 is provided in front of the switch 18. The switch lever 21 is provided on the handle portion 12 so as to be swingable back and forth around its lower end. In a normal state, the switch lever 21 is in a protruding position in which the plunger 19 of the switch 18 abuts against it and protrudes forward from the handle portion 12. When the switch lever 21 is pushed rearward from the protruding position, the plunger 19 is pushed in and the switch 18 is turned ON. A connection port 22 that opens downward is provided on the underside of the front tube portion 11 below the main unit controller 13. A female connector 23 is provided facing downward in the connection port 22. A main unit second lead wire 24 is connected to the female connector 23. The main unit second lead wire 24 is electrically connected to the main unit controller 13.

[0014] A main unit side battery mounting section 25 is provided at the bottom of the handle section 12. A main unit side battery pack 26, which serves as a power source, is slid from the rear into the main unit side battery mounting section 25. The main unit side battery pack 26 is an example of the main unit side battery of the present disclosure. The main unit side battery mounting section 25 is provided with a terminal block 27 electrically connected to the attached main unit side battery pack 26. The main unit side third lead wire 28 is connected to the terminal block 27. The main unit side third lead wire 28 is electrically connected to the main unit side controller 13. The main unit side controller 13 receives power from the main unit side battery pack 26 via the main unit side third lead wire 28 and can acquire information related to voltage from the main unit side battery pack 26. The main unit side controller 13 is provided with a main unit side notification lamp 29 exposed on the side of the front tube portion 11. For example, an LED is used for the main unit side notification lamp 29. When the voltage value acquired from the main unit side battery pack 26 falls below a predetermined value previously stored in the memory, the main unit side controller 13 lights or flashes the main unit side notification lamp 29 to notify of a voltage drop. The main unit side notification lamp 29 is an example of a notification means of the present disclosure.

[0015] The striking mechanism 6 has a tool holder 35. The tool holder 35 is rotatably held at the front side of the inner housing 2 and is cylindrical extending in the front-rear direction. Within the inner housing 2, an intermediate shaft 36 is supported at the front side of the rotating shaft 8, and a crankshaft 37 is supported at the rear side in the vertical direction. A gear 38 and a gear 39 are provided on the intermediate shaft 36 and the crankshaft 37, respectively. The gear 38 and the gear 39 are engaged with the pinion 10 of the rotating shaft 8. The intermediate shaft 36 has a first bevel gear 40 at its upper end. A switching sleeve 41 is splined to the tool holder 35. A second bevel gear 42 is rotatably mounted on the rear end of the tool holder 35 behind the switching sleeve 41. The second bevel gear 42 meshes with the first bevel gear 40 of the intermediate shaft 36. The second bevel gear 42 transmits the rotation of the first bevel gear 40 to the tool holder 35 by engaging with the switching sleeve 41 in the retracted position. The forward / rearward position of the switching sleeve 41 can be switched by a switching knob 51 provided on the rear surface of the upper outer housing 4.

[0016] A cylinder 43 is held in the rear of the inner housing 2. The cylinder 43 is inserted coaxially into the rear of the tool holder 35. A piston 44 is housed in the cylinder 43 so as to be movable back and forth. An eccentric pin 45 protrudes from the upper part of the crankshaft 37. The piston 44 and the eccentric pin 45 are connected by a connecting rod 46. A striker 48 is housed in the cylinder 43 in front of the piston 44 via an air chamber 47 so as to be movable back and forth. An impact bolt 49 is provided in the tool holder 35 in front of the striker 48. A bit B inserted into the front end of the tool holder 35 abuts against the impact bolt 49. An operation sleeve 50 for attaching and detaching the bit B is fitted to the front of the tool holder 35.

[0017] In the hammer drill 1, when the switch lever 21 is pushed, the switch 18 is turned ON. When the machine-side controller 13 receives an ON signal of the switch 18 via the machine-side first lead wire 20, it supplies power obtained from the machine-side battery pack 26 to the machine-side DC motor 7 to rotate the rotating shaft 8. Then, the crankshaft 37 rotates, and the piston 44 moves back and forth via the connecting rod 46. As a result, the linked striker 48 strikes the bit B via the impact bolt 49. When the switching sleeve 41 is switched to the backward position by operating the switching knob 51, the hammer drill mode is set in which the rotation is transmitted from the intermediate shaft 36 to the tool holder 35 via the second bevel gear 42. When the switching sleeve 41 is switched to the forward position, the hammer mode is set in which only striking is performed without rotating the tool holder 35.

[0018] Next, the dust collecting attachment 60 will be described. The dust collection attachment 60 has a box-shaped casing 61. The casing 61 includes a main body 62, a front protruding portion 63, and a rear protruding portion 64. The main body 62 extends in the vertical direction, and the front protruding portion 63 extends forward from an upper portion of the main body 62. A dust box 65 is detachably attached to the front side of the main body 62 and the lower side of the front protruding portion 63. The rear protruding portion 64 extends rearward from a lower portion of the main body 62. The main body 62 and the rear protruding portion 64 are attachable to the hammer drill 1. An upper locking protrusion 66 is formed facing upward at the center in the left-right direction on the top surface of the main body 62. The upper locking protrusion 66 is capable of being inserted into an upper locking recess 15 provided in the front cylindrical portion 11 of the hammer drill 1. A locking plate 67 is provided in the vertical direction on the upper rear surface of the main body 62. The locking plate 67 is capable of being locked in a front guide groove 14 provided on the front surface of the front tube portion 11.

[0019] A pair of side plates 68, 68 are provided on both the left and right sides from the rear surface of the main body 62 to the upper surface of the rear protruding portion 64. The front cylindrical portion 11 of the hammer drill 1 is fitted between the side plates 68, 68 from above. A pair of front and rear protrusions 69, 69 are formed on the inner surface of each side plate 68. The protrusions 69, 69 fit into lateral guide grooves 17, 17 provided on the side surface of the front cylindrical portion 11. A vertically extending recess 70 is formed on the outer surface of each side plate 68. A hook plate 71 is housed in the recess 70. The hook plate 71 is a strip-shaped plate that fits into the recess 70 and extends vertically. As shown in FIG. 2, the inside of the middle part is connected to the recess 70 so as to be rotatable around a shaft 72 in the front-rear direction. The lower part of the hook plate 71 is pressed outward to the left and right by a coil spring 73 provided between the hook plate 71 and the inner surface of the recess 70. Therefore, the hook plate 71 is biased to a lock position in which the upper part is tilted inward to the left and right as shown by the solid line in FIG. 2. The upper end of the hook plate 71 is provided with a locking claw 74 that protrudes inward. In the lock position, the locking claw 74 protrudes inward of the side plate 68 through a through hole 75 provided in the recess 70. The locking claw 74 can be locked to the horizontal locking recess 16 of the front tube part 11 at the attachment position of the dust collection attachment 60 to the hammer drill 1. When the lower portion of the hook plate 71 is pressed toward the recess 70, the hook plate 71 tilts to an unlocked position in which the locking claws 74 tilt outward to the left and right of the side plate 68, as shown by the two-dot chain lines in FIG.

[0020] A receiving portion 76 is provided on the upper surface of the rear protruding portion 64. The receiving portion 76 abuts against the lower surface of the front tubular portion 11 at the attachment position of the dust collection attachment 60. A connecting tube 77 is provided on the upper surface of the rear protruding portion 64 behind the receiving portion 76 and protrudes upward. The connecting tube 77 is located in the center of the rear protruding portion 64 in the left-right direction and holds a male connector 78 facing upward. The connecting tube 77 is connected to the connection port 22 on the lower surface of the front tubular portion 11 at the attachment position of the dust collection attachment 60, and connects the male connector 78 to the female connector 23 of the connection port 22.

[0021] A duct 80 is provided in the front protruding portion 63. The front end of the duct 80 opens forward at the front surface of the front protruding portion 63. The duct 80 is routed rearward within the front protruding portion 63 and makes a U-turn within the main body portion 62, with the rear end opening at the front surface of the main body portion 62 below the front protruding portion 63. The front end of the duct 80 is an example of a suction portion of the present disclosure. The dust box 65 is a box-shaped body that is attached to the casing 61 from the front below the front protrusion 63. The dust box 65 is formed by hingedly connecting a lid 81 and a box body 82 at their lower ends. The lid 81 has a filter 83 on its front inner surface, and the box body 82 covers the filter 83 from the front. The dust box 65 is an example of a dust collection section of the present disclosure. A locking shaft 84 is provided in the left-right direction at the lower end of the front surface of the main body 62. A receiving recess 85 is formed in the left-right direction on the lower surface of the box main body 82. The dust box 65 is detachably attached to the casing 61 by engaging the receiving recess 85 with the locking shaft 84 and locking an elastic piece 86 provided on the upper end of the lid 81 to the lower surface of the front protrusion 63. The lid 81 is provided with an inlet 87 on the upper side and an outlet 88 on the lower side. The inlet 87 is connected to the lower end of the duct 80. The outlet 88 is provided on the rear side of the filter 83.

[0022] A motor housing chamber 90 is formed as a partition within the main body 62 behind the outlet 88. When the dust box 65 is attached, the outlet 88 abuts against an opening 91 provided on the front side of the motor housing chamber 90 and is connected to the motor housing chamber 90. A dust-collection-side DC motor 92 is accommodated in the motor housing chamber 90. The dust-collection-side DC motor 92 is held in a position in which a rotating shaft 93 faces downward. A dust-collection fan 94 is fixed to the rotating shaft 93. Exhaust ports (not shown) are formed on the left and right side surfaces of the main body 62 that are radially outward of the dust-collection fan 94. The dust-collection fan 94 is an example of a fan of the present disclosure. The dust-collection side DC motor 92 is connected to positive and negative dust-collection side first lead wires 95, 95. The dust-collection side first lead wires 95, 95 are drawn into the rear protrusion 64 through a partition between the main body 62 and the rear protrusion 64. A dust-collection side controller 96 having a control circuit board (not shown) is provided in the rear protrusion 64. The dust-collection side controller 96 includes a CPU mounted on the control circuit board and a memory connected to the CPU, and controls the operation of the dust collection attachment 60 by using the CPU and the memory. The dust-collection side first lead wires 95, 95 are electrically connected to the dust-collection side controller 96. The dust-collection side controller 96 is electrically connected to the male connector 78 via a dust-collection side second lead wire 97.

[0023] A dust-collection side battery mounting section 100 is provided on the rear protruding section 64. A dust-collection side battery pack 101, which serves as the power source for the dust collection attachment 60, is slid into the dust-collection side battery mounting section 100 from the rear. The mounting structure of the dust-collection side battery pack 101 into the dust-collection side battery mounting section 100 is the same as the mounting structure of the main unit side battery pack 26 into the main unit side battery mounting section 25. The dust-collection side battery pack 101 is an example of a dust-collection side battery of the present disclosure. A terminal block 102 is provided in the dust-collection-side battery mounting section 100 to electrically connect to the mounted dust-collection-side battery pack 101. The terminal block 102 is electrically connected to the dust-collection-side controller 96 via a dust-collection-side third lead wire 103. The dust collection side controller 96 is provided with a dust collection side notification lamp 104 exposed on a side surface of the rear protrusion 64. For example, an LED is used for the dust collection side notification lamp 104. When the dust collection side battery pack 101 is attached to the dust collection side battery attachment section 100, the dust collection side controller 96 monitors the voltage of the dust collection side battery pack 101. When the voltage value of the dust collection side battery pack 101 falls below a pre-stored predetermined value, the dust collection side controller 96 lights or blinks the dust collection side notification lamp 104 to notify of a voltage drop. The dust collection side notification lamp 104 is an example of a notification means of the present disclosure.

[0024] In the dust collection system S configured as described above, with the rear protrusion 64 positioned below the front cylindrical portion 11 of the hammer drill 1, the dust collection attachment 60 vertically moves relative to the hammer drill 1 with the protrusions 69,69 of the side plates 68,68 aligned vertically with the lateral guide grooves 17,17 of the front cylindrical portion 11. Then, the protrusions 69,69 fit into the lateral guide grooves 17,17 from below, and the upper locking protrusions 66 of the main body 62 are inserted into the upper locking recesses 15 of the front cylindrical portion 11 from below. Also, the locking plate 67 of the main body 62 locks into the front guide groove 14 of the front cylindrical portion 11 from below. At this time, the hook plates 71, 71 of the side plates 68, 68 interfere with the front tubular portion 11 moving downward relatively, and swing from the locked position to the unlocked position, allowing the relative movement of the dust collection attachment 60. Then, when the dust collection attachment 60 is in the attachment position, the locking claws 74 of each hook plate 71, which has returned to the locked position, are locked into the lateral locking recesses 16 of the front tubular portion 11. Thus, downward movement of the dust collection attachment 60 relative to the hammer drill 1 is restricted, and attachment of the dust collection attachment 60 is completed. At the same time as this attachment is completed, the connection tube 77 of the rear protrusion 64 is connected to the connection port 22 of the front tube portion 11, and the male connector 78 is connected to the female connector 23. Therefore, the main unit side controller 13 is electrically connected to the dust collection side controller 96 via the main unit side second lead wire and the dust collection side second lead wire.

[0025] The bit B attached to the hammer drill 1 is a dust-suction bit having a dust-suction passage with a suction port opening at the front end at its axis and a hose attachment part (not shown) attached to its outer periphery. Therefore, a flexible hose 105 is connected between the front end of the duct 80 where suction force is generated in the dust collection attachment 60 and the hose attachment part. By connecting the flexible hose 105, a dust collection path R is formed through which air flows across the bit B and the dust collection attachment 60. As shown by the dotted arrow in Fig. 1, this dust collection path R is a path that leads from the bit B through the flexible hose 105, the duct 80, the dust box 65, and the motor housing chamber 90 to the exhaust port.

[0026] When the dust-collection-side controller 96 is electrically connected to the main-machine-side controller 13, it determines whether or not there is a voltage between the main-machine-side battery pack 26 and the dust-collection-side battery pack 101, and selects the battery pack to be used according to the determination result to execute operation control of the dust collection system S. This operation control is executed based on a program stored in advance in a non-transitory computer-readable storage medium including a memory connected to the CPU of the dust-collection-side controller 96. However, in controlling the operation of the dust collection system S, "there is voltage from the battery pack" refers to a case where there is a voltage value (e.g., 36 V) sufficient to drive each of the DC motors 7 and 92. Also, "there is no voltage from the battery pack" refers to a case where there is not a voltage value sufficient to drive each of the DC motors 7 and 92, but there is a voltage value (e.g., 5 V) necessary for the operation of the main unit controller 13 or the dust collection controller 96.

[0027] Hereinafter, the operation control of the dust collection system S will be described with reference to the flowchart of FIG. First, in step (hereinafter referred to as "S") 1, when it is confirmed that the switch 18 is ON due to the pushing operation of the switch lever 21 of the hammer drill 1, the dust-collection side controller 96 judges whether or not there is voltage from the dust-collection side battery pack 101 in S2. If it is judged that there is voltage from the dust-collection side battery pack 101, it judges whether or not there is voltage from the main unit side battery pack 26 in S3. If it is judged that there is voltage from the main unit side battery pack 26, the power source of the main unit side battery pack 26 is also supplied to the dust-collection side controller 96 of the dust collection attachment 60 in S4, and the main unit side DC motor 7 and the dust collection side DC motor 92 are driven by only the power source of the main unit side battery pack 26 in S5 to operate the hammer drill 1 and the dust collection attachment 60. The reason why the main unit side battery pack 26 is used preferentially here is that the main unit side battery pack 26 often has a larger capacity than the dust-collection side battery pack 101.

[0028] The operation of the hammer drill 1 and the dust collecting attachment 60 will now be described in detail. The main unit controller 13 receives an instruction to use the power source of the main unit battery pack 26 from the dust-collection side controller 96 together with an ON signal of the switch 18. Then, the main unit controller 13 supplies power from the main unit battery pack 26 to the dust-collection side controller 96 via the main unit side second lead wire 24 and the dust-collection side second lead wire 97. When power is thus obtained from the dust-collection side controller 96, the dust-collection side DC motor 92 is driven to rotate the rotating shaft 93, which rotates the dust-collection fan 94. Then, negative pressure is created in the dust-collection path R, and a suction force is generated at the tip opening of the bit B. The main-machine-side controller 13 waits for a preset delay time of several seconds after receiving an ON signal from the switch 18, and then supplies power obtained from the main-machine-side battery pack 26 to the main-machine-side DC motor 7. Therefore, the main-machine-side DC motor 7 is driven later than the dust-collection-side DC motor 92, causing the rotating shaft 8 to rotate, thereby rotating the intermediate shaft 36 and the crankshaft 37. Here, regardless of whether the hammer drill mode or the hammer mode is selected, the piston 44 always reciprocates, so that the bit B is struck by the linked striker 48 via the impact bolt 49.

[0029] Dust generated from the workpiece is sucked into the dust suction passage in the bit B and enters the duct 80 via the flexible hose 105. The dust then passes through the dust collection path R into the dust box 65, where it is captured by the filter 83 and stored in the box body 82. When the work is completed, the switch lever 21 is released from the depressed state, and the switch 18 turns OFF. When the main machine controller 13 confirms that the switch 18 is OFF, it stops the power supply to the main machine DC motor 7 to stop the operation of the hammer drill 1. Then, it sends an OFF signal for the switch 18 to the dust collection side controller 96. After confirming that the switch 18 is OFF, the dust collection side controller 96 waits for a preset delay time of several seconds to elapse before stopping the power supply to the dust collection side DC motor 92. Thus, dust remaining in the dust collection path R when the operation of the hammer drill 1 is stopped can be stored in the dust box 65. The dust-collection-side controller 96 confirms in S6 that the switch 18 is OFF, executes a delayed stop of the dust-collection-side DC motor 92, and then ends the operation control. If the determination in S6 shows that the switch 18 is still ON, the process returns to S2 and continues to check whether or not there is voltage in both battery packs 26, 101.

[0030] When the main-side battery pack 26 is used solely as the power source for both DC motors 7, 92 in this manner and the remaining capacity decreases, it is determined in step S3 that there is no voltage from the main-side battery pack 26. Then, in step S7, the dust-collection-side controller 96 also supplies power from the dust-collection-side battery pack 101 to the main-side controller 13 of the hammer drill 1 via the dust-collection-side second lead wire 97 and the main-side second lead wire 24. Therefore, in step S8, the dust-collection-side battery pack 101 is used solely, and the hammer drill 1 and the dust-collection attachment 60 operate only with the power from the dust-collection-side battery pack 101. On the other hand, if it is determined in step S2 that there is no voltage from the dust-collection-side battery pack 101, then in step S9 it is determined whether or not there is voltage from the main-side battery pack 26. If it is determined that there is voltage from the main-side battery pack 26, then in step S10 the main control of operation is switched to the main-side controller 13. Then, in S11, the main machine controller 13 supplies power from the main machine battery pack 26 to the dust collection controller 96 as well, and in S12, operates the hammer drill 1 and the dust collection attachment 60 using only the power from the main machine battery pack 26. If it is confirmed in S9 that there is no power supply to the main battery pack 26, then neither battery pack has any remaining capacity, and so even if the switch 18 is turned ON, the hammer drill 1 and the dust collection attachment 60 will not operate (S13). Therefore, in S14, the main controller 13 lights or flashes the main battery warning lamp 29 and the dust collection warning lamp 104 to notify that both battery packs 26, 101 are dead.

[0031] When removing the dust collection attachment 60 from the hammer drill 1, the lower parts of the left and right hook plates 71, 71 are pushed in to move each hook plate 71 to the unlocked position. Then, each locking claw 74 is released from the lateral locking recess 16 of the front tubular part 11, allowing the dust collection attachment 60 to move relatively. Thus, the dust collection attachment 60 can be moved relatively away from the hammer drill 1 in the opposite direction to that during attachment. Then, the protrusions 69, 69 of the side plates 68, 68 are released from the lateral guide grooves 17, 17 of the front tubular part 11, and the locking plate 67 of the main body part 62 is moved downwardly away from the front guide groove 14. At the same time, the upper locking protrusion 66 of the main body part 62 is removed from the upper locking recess 15 of the front tubular part 11. In this manner, removal of the dust collection attachment 60 is completed. When disposing of the dust stored in the dust box 65, the elastic piece 86 is pushed down to release the engagement with the front protrusion 63. Then, the dust box 65 can be removed from the casing 61 by simply tipping the dust box 65 forward about the engagement shaft 84. When the lid 81 is opened, the dust stored inside the box body 82 can be disposed of.

[0032] The dust collection system S of the above-described embodiment includes a hammer drill 1 having a switch 18 that is operated ON / OFF, a main unit DC motor 7, a main unit controller 13 that controls the main unit DC motor 7 based on the ON / OFF operation of the switch 18, and a main unit battery pack 26. The dust collection system S also includes a dust collection attachment 60 that is attached to the hammer drill 1 to collect dust generated when the hammer drill 1 is used, and has a duct 80, a dust box 65 that captures dust sucked through the suction part of the duct 80, a dust collection fan 94 that generates suction force in the duct 80, a dust collection side DC motor 92 that rotates the dust collection fan 94, a dust collection side controller 96 that controls the dust collection side DC motor 92, and a dust collection side battery pack 101. Then, with the dust collection attachment 60 attached to the hammer drill 1, the main machine side controller 13 and the dust collection side controller 96 are electrically connected, and the main machine side battery pack 26 and the dust collection side battery pack 101 can be used independently by the dust collection side controller 96 as power sources for the main machine side DC motor 7 and the dust collection side DC motor 92, respectively. With this configuration, even if the hammer drill 1 and the dust collection attachment 60 each have a battery pack as a power source, it is possible to prevent the operation of either one from stopping due to the battery running out, thereby improving usability. Also, since the two battery packs 26, 101 can be used in turn until they are used up, the usage efficiency of both battery packs 26, 101 is also improved.

[0033] The dust-collection-side controller 96 first uses the main-unit-side battery pack 26 solely as a power source for both DC motors 7, 92, and then uses the dust-collection-side battery pack 101 solely as a power source for both DC motors 7, 92 (S1 to S8). Therefore, the main unit side battery pack 26, which often has a larger capacity than the dust-collection side battery pack 101, can be used preferentially. The dust collection side controller 96 monitors the voltages of both battery packs 26, 101, and when the voltage value of one of the battery packs 26 (101), which was previously used solely as the power source for both DC motors 7, 92, falls below a predetermined value at which both DC motors 7, 92 cannot be driven, the dust collection side controller 96 uses the other battery pack 101 (26) as the power source for both DC motors 7, 92 (S1 to S12). Therefore, the two battery packs 26, 101 can be used depending on the voltage value, and operation stop due to one of the batteries running out can be effectively prevented. The dust collection side controller 96 determines the battery pack 26 (101) to be used solely as the power source for both DC motors 7, 92, and when the voltage value of the battery pack 26 (101) becomes equal to or lower than a predetermined value, the main unit side controller 13 determines the battery pack 101 (26) to be used solely as the power source for both DC motors 7, 92 (S10 to S12). Therefore, the use of the main-unit-side battery pack 26 is suppressed, while the operation control of the dust collection system S can be continued even if the voltage value of the dust-collection-side battery pack 101 drops.

[0034] The main machine side battery pack 26 is attachable / detachable to the main machine side battery mounting portion 25 provided on the hammer drill 1, and the dust collection side battery pack 101 is attachable / detachable to the dust collection side battery mounting portion 100 provided on the dust collection attachment 60, and the attachment / detachment structures of both the main machine side battery mounting portion 25 and the dust collection side battery mounting portion 100 are the same. Therefore, if the rated voltage is the same, either of the battery packs 26, 101 can be attached to the hammer drill 1 and the dust collection attachment 60, improving usability. When the switch 18 is turned on, the dust-collection-side controller 96 first drives the dust-collection-side DC motor 92 and then drives the main-machine-side DC motor 7 . Therefore, the dust collecting attachment 60 can be operated first to generate suction force, and the suction of dust can be reliably performed simultaneously with the work by the hammer drill 1. When the switch 18 is turned OFF, the dust-collection-side controller 96 stops driving the dust-collection-side DC motor 92 after the main-machine-side DC motor 7 has stopped driving. Therefore, dust can be collected in the dust box 65 without remaining in the dust collection path R after the operation of the hammer drill 1 is stopped. A main unit side notification lamp 29 and a dust collection side notification lamp 104 are provided to notify the user when the voltages of the main unit side battery pack 26 and the dust collection side battery pack 101 fall below a predetermined value. Therefore, the worker can quickly take measures such as replacing or charging both battery packs 26, 101.

[0035] Modifications of the present disclosure will be described below. In the above-described operational control, the battery pack on the main unit side is first used solely as the power source for both DC motors, and then the battery pack on the dust collection side is used solely as the power source for both DC motors. However, the opposite may also be true, in which the battery pack on the dust collection side is first used solely as the power source for both DC motors, and then the battery pack on the main unit side is used solely as the power source for both DC motors. In this case, the remaining capacity of the battery pack on the main unit can be prevented from decreasing, and a power source can be secured when the hammer drill is used alone. In the above-described operation control, a determination is made that there is no voltage when both battery packs do not have a sufficient voltage value to drive both DC motors, but the machine side controller or the dust collection side controller may also determine that there is no voltage even when either one of the battery packs is not attached to the battery attachment section, and use the other battery pack solely as the power source for both DC motors. In this case, the entire system can be operated with just one battery pack attached, which leads to further improvements in usability. Furthermore, the decision of the battery pack to be used solely as a power source is not limited to being based on the voltage value of the battery pack. For example, each battery mounting section may be provided with a detection means such as a sensor or switch for detecting the mounting of a battery pack, and the battery pack to be used solely as a power source may be decided based on whether or not a battery pack is mounted.

[0036] In the hammer drill, the position and orientation of the main DC motor and the main controller are not limited to those in the above embodiment. For example, the main DC motor may be oriented with the rotation shaft facing forward or diagonally forward, and the main controller may be oriented sideways. The position of the main battery attachment can also be changed as needed. The main battery pack can be slid in from the front or side instead of the rear. If two main battery packs are attached, they can be used separately as one main battery and used separately from the dust collection battery. However, the main battery of the present disclosure is not limited to a detachable one like the main battery pack of the above embodiment. For example, the main battery may be one that is non-detachably held in the housing of the power tool and can be charged via a cable. The structure of the striking mechanism is not limited to that of the above embodiment. The operation mode may be one in which a drill mode can be selected. The power tool is not limited to a hammer drill, but may be another power tool such as an electric hammer. In the above embodiment, a dust-collecting bit is used as the tip tool attached to the power tool, but the tip tool does not have to be a dust-collecting bit. In this case, a separate cylindrical attachment that covers the outside of the tip tool may be attached to the tip of the power tool, and a hose attachment part provided on the attachment and the suction part of the dust-collecting attachment may be connected by a flexible hose.

[0037] The attachment direction of the dust collection attachment to the power tool is not limited to the up-down direction, but may be, for example, the front-rear direction. In the dust collection attachment, the position and orientation of the dust collection side DC motor and the position and structure of the dust box are not limited to those in the above embodiment. For example, the dust collection side DC motor may be housed with the rotation shaft facing upward or sideways. The dust collection side DC motor and the fan shaft may be separate, and rotation may be transmitted from the rotation shaft of the dust collection side DC motor to the fan shaft. The dust collecting section is not limited to a dust box, and may be a cyclone structure without a filter. Therefore, the dust collecting path can be changed as appropriate. The dust-collection side battery pack may also be slid onto the dust-collection side battery mounting portion from the front or side instead of from the rear. However, the dust-collection-side battery of the present disclosure is not limited to being detachable like the dust-collection-side battery pack of the above embodiment. For example, the dust-collection-side battery may be held in an undetachable manner in the casing of the dust collection attachment and may be charged via a cable. In the dust collection attachment, the connection part of the flexible hose may be at another position such as the top surface or side surface instead of the front surface of the casing. However, the dust collection attachment may not use a flexible hose. For example, the dust collection attachment may have a cylindrical slide part that protrudes from the casing with a dust collection path provided therein, and a suction port through which a tool tip passes is provided at the tip of the slide part. The notification means is not limited to a lamp, and may be, for example, a display of letters or numbers, a sound such as an electronic tone, or a combination of a lamp and a sound. [Explanation of symbols]

[0038] 1 Hammer drill, 2 Inner housing, 3 Motor housing, 4 Upper outer housing, 5 Lower outer housing, 6 Impact mechanism, 7 Machine side DC motor, 8 Rotating shaft, 11 Front tube, 12 Handle, 13 Machine side controller, 18 Switch, 21 Switch lever, 23 Female connector, 25 Machine side battery attachment part, 26 Machine side battery pack, 29 Machine side warning lamp, 35 Tool holder, 44 Piston a dust collection attachment, 48··striker, 49··impact bolt, 60··dust collection attachment, 61··casing, 62··main body, 65··dust box, 71··hook plate, 78··male connector, 83··filter, 92··dust collection side DC motor, 94··dust collection fan, 96··dust collection side controller, 100··dust collection side battery attachment portion, 101··dust collection side battery pack, 104··dust collection side warning lamp, B··bit, R··dust collection path, S··dust collection system for power tools.

Claims

1. An electric power tool comprising: an ON / OFF switch; a DC motor on the machine side; a controller on the machine side that controls the DC motor on the machine side based on the ON / OFF operation of the switch; and a battery on the machine side. A dust collection system for a power tool, comprising a dust collection attachment attached to the power tool for collecting dust generated when the power tool is used, the attachment having a suction unit, a dust collection unit for capturing dust sucked from the suction unit, a fan for generating suction force in the suction unit, a dust collection side DC motor for rotating the fan, a dust collection side controller for controlling the dust collection side DC motor, and a dust collection side battery, A dust collection system for power tools, characterized in that, with the dust collection attachment attached to the power tool, the main unit controller and the dust collection controller are electrically connected, and the main unit battery and the dust collection battery can be used independently by the main unit controller or the dust collection controller as power sources for the main unit DC motor and the dust collection DC motor, respectively.

2. The dust collection system for power tools according to claim 1, characterized in that the main unit controller or the dust collection controller first uses the main unit battery alone as a power source for both DC motors, and then uses the dust collection battery alone as a power source for both DC motors.

3. The power tool dust collection system according to claim 1, characterized in that the main unit controller or the dust collection controller first uses the dust collection battery alone as a power source for both DC motors, and then uses the main unit battery alone as a power source for both DC motors.

4. The dust collection system for power tools according to any one of claims 1 to 3, characterized in that the controller on the main unit side or the dust collection side controller monitors the voltage of both batteries, and when the voltage of one of the batteries that was previously used alone as the power source for both DC motors falls below a predetermined value that prevents both DC motors from being driven, the other battery is used alone as the power source for both DC motors.

5. The dust collection system for power tools according to claim 4, characterized in that the dust collection side controller determines which battery to be used alone as the power source for both DC motors, and when the voltage value of the dust collection side battery falls below a predetermined value, the main unit side controller determines which battery to be used alone as the power source for both DC motors.

6. The power tool dust collection system according to any one of claims 1 to 3, characterized in that the main unit battery is detachable from the main unit battery mounting section provided on the power tool, the dust collection battery is detachable from the dust collection battery mounting section provided on the dust collection attachment, and the attachment and detachment structures for the batteries in the main unit battery mounting section and the dust collection battery mounting section are the same.

7. The dust collection system for power tools according to claim 6, characterized in that the main unit controller or the dust collection controller uses the other battery alone as a power source for both DC motors even when one of the two batteries is not installed in the battery mounting section.

8. The power tool dust collection system according to any one of claims 1 to 3, characterized in that the main unit controller or the dust collection controller drives the dust collection DC motor first and then the main unit DC motor in response to the ON operation of the switch.

9. The power tool dust collection system according to any one of claims 1 to 3, characterized in that the main unit controller or the dust collection controller stops driving the dust collection DC motor after the main unit DC motor stops driving in conjunction with the OFF operation of the switch.

10. The power tool dust collection system according to claim 4, characterized in that it is provided with notification means for notifying when the voltage of the main unit battery and the dust collection battery falls below a predetermined value.

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