A hand-held percussion electric drill

Abstract

The application discloses a handheld impact electric drill, which comprises a shell and a rotating shaft, a carbon brush assembly matched with the rotating shaft is arranged on the shell, and the carbon brush assembly is connected with the shell through a micro motor; the carbon brush assembly comprises a rotating plate and carbon brushes symmetrically arranged at both ends of the rotating plate; a contact hole is arranged on the carbon brush, a contact assembly matched with the contact hole is arranged in the shell; the contact assembly comprises a contact sheet and a first spring, a magnetic attraction plate is arranged on the contact sheet, and an electromagnet matched with the magnetic attraction plate is arranged in the shell; guide sleeves capable of accommodating the carbon brushes are arranged at both ends of the rotating plate, and a first button and a second button electrically connected with the micro motor and the electromagnet are arranged in the guide sleeves; the application provides a device capable of automatically replacing the worn carbon brushes in the electric drill, the length of the worn carbon brush is automatically detected to automatically replace the carbon brush, the device avoids the trouble of manually disassembling the electric drill for replacement, and the use efficiency of the electric drill is improved.

Description

Technical Field

[0001] This invention relates to the field of electric drill technology, and in particular to a handheld impact drill. Background Technology

[0002] Handheld impact drills, due to their high power, typically use a plug-in power supply instead of lithium batteries. Existing impact drill motors usually have two symmetrically arranged carbon brushes. The carbon brushes are usually pressed onto the shaft by springs and are in contact with the shaft, which is a sliding contact component.

[0003] Carbon brushes are extremely prone to wear because they are in contact with the shaft for extended periods and are made of graphite. Existing carbon brushes are usually located inside the electric drill, and when the carbon brushes need to be replaced, the electric drill housing must be disassembled, which is very inconvenient. Secondly, the degree of wear of carbon brushes is usually judged by human experience, making it impossible to accurately replace worn carbon brushes in a timely manner. Summary of the Invention

[0004] This invention addresses the shortcomings of existing technologies by providing a handheld impact drill.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a handheld impact drill, comprising a housing and a rotating shaft.

[0006] In the above scheme, preferably, the housing is provided with a carbon brush assembly that cooperates with the rotating shaft, and the carbon brush assembly is connected to the housing via a micro motor;

[0007] The carbon brush assembly includes a rotating plate and carbon brushes symmetrically arranged at both ends of the rotating plate.

[0008] The carbon brush is provided with contact holes, and the housing is provided with contact components that mate with the contact holes;

[0009] The contact assembly includes a contact piece and a first spring. The contact piece is provided with a magnetic plate, and the housing is provided with an electromagnet that cooperates with the magnetic plate.

[0010] The rotating plate has guide sleeves at both ends that can accommodate carbon brushes. The guide sleeves are equipped with a first button and a second button that are electrically connected to the WeChat motor and the electromagnet.

[0011] After the carbon brush wears down, the contact piece slides down and contacts the first button and the second button.

[0012] In the above scheme, preferably, the guide sleeve is provided with a clamping assembly for clamping carbon brushes. The clamping assembly includes a clamping rod, a top plate and a first pull rope. The clamping rod is slidably disposed on both sides of the guide sleeve, and a second spring is provided between the top plate and the guide sleeve.

[0013] In the above scheme, preferably, a rope block connected to the first rope is slidably provided on the rotating plate, a groove that cooperates with the rope block is provided on the rotating plate, a third spring is provided between the rope block and the rotating plate, and a guide block for guiding the first rope is provided on the rotating plate.

[0014] In the above scheme, preferably, the pull rope block is provided with a top pin, and the housing is provided with a drive block that cooperates with the top pin. The drive block drives the top pin to slide and pull the first pull rope.

[0015] In the above scheme, preferably, the outer shell is provided with a feeding assembly that cooperates with the guide sleeve. The feeding assembly includes an electric push rod, a vacuum push rod and a feeding box. The feeding box is provided with a plurality of carbon brushes. A fourth spring is provided between the carbon brushes and the feeding box. The feeding box is provided with a clamping plate that cooperates with the carbon brushes.

[0016] In the above scheme, preferably, the electric push rod is provided with a push rod, the vacuum push rod includes a suction cup rod and a cylinder sleeve, the suction cup rod is connected to the push rod, one end of the suction cup rod is provided with a suction cup, and the other end is slidably disposed in the cylinder sleeve, and the suction cup rod is provided with a suction hole that is connected to the suction cup and the cylinder sleeve cavity.

[0017] In the above scheme, preferably, the housing is provided with a third button that cooperates with the top pin, and the third button is electrically connected to the electric push rod.

[0018] In the above scheme, preferably, a first mounting plate is fixed inside the housing, the driving blocks are symmetrically arranged at both ends of the first mounting plate, and the third button is located on the first mounting plate near the inner end of the housing.

[0019] The beneficial effects of the present invention are: the present invention provides a device for automatically replacing worn carbon brushes inside an electric drill. By automatically detecting the length of the worn carbon brush, the device automatically replaces the carbon brush, eliminating the trouble of manually disassembling the electric drill for replacement and improving the efficiency of the electric drill. Attached Figure Description

[0020] Figure 1 This is a front-view stereoscopic structural diagram of the present invention.

[0021] Figure 2 This is a rear-view stereoscopic structural diagram of the present invention.

[0022] Figure 3 This is a partial enlarged structural diagram of point A in the present invention.

[0023] Figure 4 This is a cross-sectional structural diagram of the present invention.

[0024] Figure 5 This is a partial enlarged structural diagram of section B of the present invention.

[0025] Figure 6 This is a cross-sectional view of the clamping component of the present invention.

[0026] Figure 7 This is a three-dimensional structural diagram of the carbon brush assembly of the present invention.

[0027] Figure 8 This is a schematic diagram of the exploded structure of the feeding assembly of the present invention.

[0028] Figure 9 This is a cross-sectional view of the vacuum actuator of the present invention. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: See also Figures 1-9 A handheld impact drill includes a housing 1 and a rotating shaft 2. The rotating shaft 2 is the drill spindle. Carbon brushes that contact and cooperate with the rotating shaft 2 are provided inside the housing 1. This is existing technology and will not be described in detail here.

[0030] The housing 1 is provided with a carbon brush assembly that cooperates with the rotating shaft 2. The carbon brush assembly is rotatably disposed inside the housing 1. Specifically, a micro motor 3 is fixed inside the housing 1. The output end of the micro motor 3 is connected to the carbon brush assembly, that is, when the micro motor 3 is energized, it can drive the carbon brush assembly to rotate. Preferably, the micro motor 3 can drive the carbon brush assembly to rotate 180° once it is energized.

[0031] The carbon brush assembly includes a rotating plate 4 and carbon brushes 5 symmetrically arranged at both ends of the rotating plate 4. The rotating plate 4 is fixedly connected to the output shaft of the micro motor 3. Guide sleeves 11 are fixedly provided at both ends of the rotating plate 4, and the carbon brushes 5 can slide within the guide sleeves 11.

[0032] Initially, the carbon brush 5 at one end of the rotating plate 4 is in contact with the rotating shaft 2. Specifically, one end of the carbon brush 5 is in contact with the rotating shaft 2, and the other end is provided with a contact hole 6. The housing 1 is provided with a contact assembly that cooperates with the contact hole 6. Specifically, the contact assembly includes a contact piece 7 and a first spring 8. The contact piece 7 is provided with a contact rod that cooperates with the contact hole 6. When engaged, the contact rod extends into the contact hole 6, so that the contact piece 7 and the carbon brush 5 are integrally connected. The housing 1 is provided with a metal sheet that is electrically connected to the contact piece 7. The contact piece 7 and the metal sheet are preferably connected by a flexible wire.

[0033] The housing 1 is provided with a second mounting plate 101, on which an electromagnet 10 that can attract the contact piece 7 is fixed. The contact piece 7 is provided with a magnetic suction plate 9 that cooperates with the electromagnet 10 on the side facing the electromagnet 10. That is, when the electromagnet 10 is energized, it can attract the contact piece 7, causing the contact piece 7 to detach from the carbon brush 5. A first spring 8 is provided between the second mounting plate 101 and the contact piece 7. The two ends of the first spring 8 abut against the contact piece 7 and the second mounting plate 101 respectively. That is, when the electromagnet 10 is not energized, the first spring 8 abuts against the contact piece 7, causing the carbon brush 5 to contact the rotating shaft 2. As the carbon brush 5 wears, the contact piece 7 gradually slides closer to the center of the rotating shaft 2.

[0034] The carbon brush 5 is preferably rectangular, and the contact piece 7 is circular. The diameter of the contact piece 7 is preferably larger than the short side of the rectangular carbon brush 5, that is, when the contact piece 7 is engaged with the carbon brush 5, part of it is placed outside the carbon brush 5. The guide sleeve 11 is preferably rectangular and engages with the carbon brush 5. Its upper half is provided with an arc-shaped opening that engages with the contact piece 7, that is, the contact piece 7 can slide a certain distance inside the guide sleeve 11. The guide sleeve 11 is provided with a first button 12 and a second button 13 that engage with the contact piece 7. That is, when the contact piece 7 slides toward the center of the rotating shaft 2, it can contact the first button 12 and the second button 13 to trigger the button. The first button 12 is electrically connected to the micro motor 3, and the second button 13 is electrically connected to the electromagnet 10.

[0035] During use, as the carbon brush 5 wears down, the contact piece 7 gradually slides down until it contacts the first button 12 and the second button 13. At this time, the electromagnet 10 is energized and attracts the contact piece 7, causing the contact piece 7 to disengage from the carbon brush 5. The micro motor 3 then rotates 180° to rotate the intact carbon brush 5 on the other side to one end of the shaft 2. Subsequently, the electromagnet 10 is de-energized, causing the contact piece 7 to contact and engage with the contact hole 6 on the new carbon brush 5 through the elastic force of the first spring 8.

[0036] To prevent the carbon brush 5 from falling off when rotating within the guide sleeve 11, and to ensure that the carbon brush 5 slides only under the force of the first spring 8 during use, the guide sleeve 11 is symmetrically equipped with clamping assemblies for holding the carbon brush 5. Each clamping assembly includes a clamping rod 21, a top plate 22, and a first pull cord 23. The guide sleeve 11 has a sliding cavity. The clamping rod 21 is fixedly connected to the top plate 22, which slidably rests within the sliding cavity. After passing through the guide sleeve 11, the clamping rod 21 can contact the side wall of the carbon brush 5. Figure 6 As shown, one end of the top plate 22 is connected to the clamping rod 21, and the other end is provided with a second spring 24 between it and the cavity wall of the sliding cavity away from the carbon brush 5. The two ends of the second spring 24 abut against the top plate 22 and the cavity wall of the sliding cavity, respectively. One end of the first pull rope 23 is fixed on the top plate 22. When the top plate 22 is not subjected to external force, the second spring 24 abuts against the top plate 22, causing the clamping rod 21 to contact the side wall of the carbon brush 5, thereby fixing the carbon brush 5 in the guide sleeve 11.

[0037] A rope block 31 connected to the first rope 23 is slidably mounted on the rotating plate 4. The rotating plate 4 has a groove 32 that mates with the rope block 31. The rope block 31 is slidably engaged within the groove 32. A third spring 33 is provided between the rope block 31 and the rotating plate 4. A guide block 34 is provided on the rotating plate 4 to guide the first rope 23. Specifically, one end of the first rope 23 is fixed to the top plate 22, and the other end passes through the guide block 34 and is fixedly connected to the rope block 31. Figure 7 As shown, when the pull rope block 31 slides towards the side closer to the guide sleeve 11, it can pull the first pull rope 23, thereby driving the top plate 22 to compress the second spring 24, causing the clamping rod 21 to disengage from the carbon brush 5.

[0038] The upper end of the pull rope block 31 is connected to the first pull rope 23, and the lower end is fixed with a top pin 35. The housing 1 is fixed with a first mounting plate 61. The two ends of the first mounting plate 61 are fixed with driving blocks 36 that cooperate with the top pin 35. That is, when the top pin 35 rotates to the driving block 36, the driving block 36 causes the top pin 35 to slide, thereby driving the pull rope block 31 to slide closer to the guide sleeve 11, thereby unlocking the clamping rod 21. That is, when the carbon brush 5 is in use, the clamping rod 21 does not contact the carbon brush 5. When the rotating plate 4 rotates and causes the driving block 36 to disengage from the top pin 35, the clamping rod 21 contacts the carbon brush 5 and clamps the carbon brush 5, thereby ensuring that neither the new carbon brush nor the old carbon brush falls off when the carbon brush is rotated for replacement. The two ends of the driving block 36 are provided with arc-shaped surfaces that transition with the top pin 35.

[0039] To facilitate the replacement and replenishment of carbon brush 5, the outer surface of the housing 1 is provided with a feeding assembly that cooperates with the guide sleeve 11 at the other end. The feeding assembly includes an electric push rod 41, a vacuum push rod 42, and a feeding box 43. The electric push rod 41 is preferably a miniature push rod, which includes an ejector rod 51. The vacuum push rod 42 includes a suction cup rod 52 and a cylinder sleeve 53. The electric push rod 41 and the cylinder sleeve 53 are both fixed on the outer surface of the housing 1. The ejector rod 51 and the suction cup rod 52 are fixedly connected, that is, the ejector rod 51 and the suction cup rod 52 can slide synchronously. When the electric push rod 41 is energized, it can drive the suction cup rod 52 to move.

[0040] One end of the suction rod 52 is fixed with a suction cup 54, and the other end is slidably disposed in the cylinder sleeve 53 via a piston. The suction rod 52 is provided with a suction hole 55 that communicates with the suction cup 54 and the internal cavity of the cylinder sleeve 53. That is, when the piston slides down, a negative pressure is generated in the cylinder sleeve 53, causing the suction cup 54 to generate an adsorption force.

[0041] The feed box 43 contains several stored new carbon brushes 5, and a fourth spring 44 is provided between the carbon brushes 5 and the feed box 43. Figure 8As shown, the carbon brush 5 is elastically connected to the feed box 43 on the right side via a fourth spring 44. The feed box 43 has a clamping plate 45 on the left side that can hold the carbon brush 5. That is, initially, when the electric push rod 41 pushes the rod 51 to the uppermost position, the carbon brush 5 is clamped in the clamping plate 45 on the left side. After the electric push rod 41 is driven, the suction cup 54 can contact the upper surface of the carbon brush 5, thereby generating an adsorption force to adsorb the carbon brush 5 and further push it into the guide sleeve 11. When the rotating plate 4 rotates, the carbon brush 5 is disengaged from the suction cup 54.

[0042] The first mounting plate 61 has a third button 56 near the rotating shaft 2, which mates with the top pin 35. The third button 56 is electrically connected to the electric push rod 41. Figure 2 The electric push rod 41 is in its initial position. When the rotating plate 4 rotates, the top pin 35 disengages from the third button 56. At this time, the electric push rod 41 is triggered to complete one lifting and lowering cycle. After the rotating plate 4 rotates 180°, the electric push rod 41 pushes the new carbon brush 5 in the feed box 43 into the guide sleeve 11 on that side.

[0043] Using the above-described method of a handheld impact drill: During use, the carbon brush at one end of the rotating shaft 2 is in continuous contact with the rotating shaft 2, and thus gradually wears down, causing the contact piece 7 to slide towards the center of the rotating shaft 2 within the guide sleeve 11. After the carbon brush wears down to a certain extent, the contact piece 7 contacts the first button 12 and the second button 13, triggering the buttons and thus energizing the electromagnet 10, which in turn drives the micro motor 3 synchronously.

[0044] When the electromagnet 10 is energized, it attracts the contact piece 7, causing the contact piece 7 to disengage from the worn carbon brush 5. At the same time, the micro motor 3 rotates, causing the rotating plate 4 to rotate 180°. During the rotation, the clamping assembly disengages from the drive block 36 due to the top pin 35 on the pull rope block 31, thereby clamping the carbon brush 5 with the clamping rod 21, ensuring that the carbon brush inside the guide sleeve 11 does not fall off.

[0045] After rotating 180°, the new carbon brush 5 is placed at one end of the rotating shaft 2, the electromagnet 10 is de-energized again, so that the contact piece 7 contacts the new carbon brush and resumes normal operation;

[0046] While the rotating plate 4 is rotating, the top pin 35 disengages from the third button 56, triggering the electric push rod 41 to complete one lifting and lowering cycle. After the rotating plate 4 rotates 180°, the electric push rod 41 pushes the new carbon brush 5 in the feed box 43 into the guide sleeve 11 on that side.

[0047] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A handheld impact drill, comprising a housing (1) and a rotating shaft (2), characterized in that: The housing (1) is provided with a carbon brush assembly that cooperates with the rotating shaft (2), and the carbon brush assembly is connected to the housing (1) via a micro motor (3); The carbon brush assembly includes a rotating plate (4) and carbon brushes (5) symmetrically arranged at both ends of the rotating plate (4). The carbon brush (5) is provided with a contact hole (6), and the housing (1) is provided with a contact assembly that mates with the contact hole (6); The contact assembly includes a contact piece (7) and a first spring (8). A magnetic plate (9) is provided on the contact piece (7), and an electromagnet (10) that cooperates with the magnetic plate (9) is provided inside the housing (1). The rotating plate (4) has guide sleeves (11) at both ends that can accommodate carbon brushes (5). The guide sleeves (11) are equipped with a first button (12) and a second button (13) that are electrically connected to the micro motor (3) and the electromagnet (10). The contact piece (7) slides down and contacts the first button (12) and the second button (13) after the carbon brush (5) wears down.

2. A handheld impact drill according to claim 1, characterized in that: The guide sleeve (11) is provided with a clamping assembly for clamping carbon brush (5). The clamping assembly includes a clamping rod (21), a top plate (22) and a first pull rope (23). The clamping rod (21) is slidably disposed on both sides of the guide sleeve (11). A second spring (24) is provided between the top plate (22) and the guide sleeve (11).

3. A handheld impact drill according to claim 2, characterized in that: The rotating plate (4) is slidably provided with a rope block (31) connected to the first rope (23), the rotating plate (4) is provided with a groove (32) that cooperates with the rope block (31), a third spring (33) is provided between the rope block (31) and the rotating plate (4), and a guide block (34) is provided on the rotating plate (4) to guide the first rope (23).

4. A handheld impact drill according to claim 3, characterized in that: The pull rope block (31) is provided with a top pin (35), and the housing (1) is provided with a drive block (36) that cooperates with the top pin (35). The drive block (36) drives the top pin (35) to slide and pull the first pull rope (23).

5. A handheld impact drill according to claim 4, characterized in that: The housing (1) is provided with a feeding assembly that cooperates with the guide sleeve (11). The feeding assembly includes an electric push rod (41), a vacuum push rod (42) and a feeding box (43). The feeding box (43) is provided with a number of carbon brushes (5). A fourth spring (44) is provided between the carbon brushes (5) and the feeding box (43). The feeding box (43) is provided with a clamping plate (45) that cooperates with the carbon brushes (5).

6. A handheld impact drill according to claim 5, characterized in that: The electric push rod (41) is provided with a push rod (51). The vacuum push rod (42) includes a suction rod (52) and a cylinder sleeve (53). The suction rod (52) is connected to the push rod (51). One end of the suction rod (52) is provided with a suction cup (54), and the other end is slidably disposed in the cylinder sleeve (53). The suction rod (52) is provided with a suction hole (55) that is connected to the cavity of the suction cup (54) and the cylinder sleeve (53).

7. A handheld impact drill according to claim 6, characterized in that: The housing (1) is provided with a third button (56) that cooperates with the top pin (35), and the third button (56) is electrically connected to the electric push rod (41).

8. A handheld impact drill according to claim 7, characterized in that: The housing (1) is fixedly provided with a first mounting plate (61), the drive block (36) is symmetrically arranged at both ends of the first mounting plate (61), and the third button (56) is located on the first mounting plate (61) near the inner end of the housing (1).

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