Drywall screwdriver

Abstract

The invention relates to a drywall screwdriver with a housing (10), a screw-in depth limiting element (12), a gear unit (14), an output spindle (16), a drive unit (18), and a clutch unit (20) designed to couple and / or decouple a torque transmission from the gear unit (14) to the output spindle (16). It is proposed that a gear element (22) of the gear unit (14) be fixedly connected to at least one clutch element (24) of the clutch unit (20).

Description

State of the art

[0001] Drywall screwdrivers with a housing, with a screw-in depth limiting element, with a gear unit, with an output spindle, with a drive unit and with a coupling unit which is intended to couple and / or decouple a torque transmission of the gear unit to the output spindle are already known. Disclosure of the invention

[0002] The invention relates to a drywall screwdriver with a housing, with a screw-in depth limiting element, with a gear unit, with an output spindle, with a drive unit and with a coupling unit which is intended to couple and / or decouple a torque transmission of the gear unit to the output spindle.

[0003] It is proposed that a gear element of the gear unit be firmly connected to at least one coupling element of the coupling unit. In this context, a "drywall screwdriver" is understood to mean, in particular, a handheld power tool intended, in particular, to process materials such as plasterboard, and preferably to screw screws into materials such as plasterboard. "Intended" is understood to mean, in particular, specially designed, configured, and / or equipped. A "screw-in depth limiting element" is understood, in this context, to mean, in particular, an element intended, at least essentially, to limit the screw-in depth of the drywall screwdriver. In a particularly preferred embodiment, the screw-in depth limiting element has a depth stop.Preferably, the screw-in depth of the screw-in depth limiting element can be configured to be adjustable. However, other limiting parameters that appear appropriate to a person skilled in the art, such as a speed or torque, are also conceivable. The screw-in depth limiting element can be configured electronically, magnetically, optically, or in another way that appears appropriate to a person skilled in the art. In a particularly preferred embodiment, the screw-in depth limiting element is configured mechanically. A "gear unit" is understood in particular to mean a unit that is intended to transform an incoming torque into a different outgoing torque and / or to transform an input speed into a different output speed. Advantageously, this should be understood in particular to mean a gear transmission, more advantageously a spur gear transmission, and especially advantageously a planetary transmission.Furthermore, a "drive unit" should be understood in particular as an electrical and / or mechanical motor unit which, during operation, is advantageously provided for generating a rotary movement. Advantageously, this should be understood in particular as an electric motor. A "clutch unit" should be understood in particular as a unit which is intended to transmit torque and / or prevent torque transmission, wherein the torque is transmitted unchanged via the clutch unit when the clutch unit is closed. Advantageously, this should be understood in particular as a form-locking clutch, particularly advantageously as an engagement clutch. The clutch unit comprises at least two, preferably three clutch elements, wherein preferably two clutch elements are permanently coupled during operation and only partially disengage axially and / or rotate relative to one another in the circumferential direction.A "transmission element" is understood to mean, in particular, an element of the transmission unit that is intended for torque transmission and / or torque variation. Advantageously, this is understood to mean, in particular, a gearwheel, and particularly advantageously, a planetary carrier element. A "clutch element" is understood to mean, in particular, an element that is intended to perform a clutch movement and / or assume a clutch position. The clutch movement can effect engagement and / or disengagement and / or advantageously support engagement and / or disengagement. The clutch position serves, in particular, to transmit a force, in particular a torque, via a positive and / or non-positive connection. The positive and / or non-positive connection is intended, in particular, for transmitting a torque.This is advantageously understood to mean, in particular, a form-fitting coupling element, particularly advantageously a claw coupling element. The design according to the invention advantageously allows for savings in components, installation space, and weight. Furthermore, a small tolerance between the output spindle and a motor spindle can be achieved.

[0004] It is further proposed that the transmission element of the transmission unit be at least partially integrally formed with the at least one clutch element of the clutch unit. "At least partially integrally formed" is to be understood in particular as meaning that at least individual elements and / or individual components of two units are integrally formed with one another. "Integrally formed" is to be understood in particular as meaning at least materially connected, for example, by a welding process, an adhesive process, an injection molding process, and / or another process deemed appropriate by a person skilled in the art, and / or advantageously formed in one piece, such as by production from a single casting and / or by production using a single- or multi-component injection molding process, and advantageously from a single blank. This in turn advantageously allows for savings in components, installation space, weight, and assembly effort.

[0005] It is further proposed that the gear unit comprise at least one planetary gear. The planetary gear preferably comprises at least two, preferably three planetary gears and at least one sun gear or pinion. Furthermore, the planetary gear preferably comprises a planetary carrier element comprising at least two, preferably three bolts intended to support the planetary gears. Furthermore, the planetary gear preferably has at least one ring gear.

[0006] This allows for an advantageously short and compact design of the drywall screwdriver, particularly in the axial direction. Furthermore, the use of a planetary gear unit allows for a particularly robust and cost-effective design of the gear unit. Furthermore, a beneficially symmetrical design and an advantageous transmission of forces and torques from the drive unit via the gear unit to the output spindle can be achieved.

[0007] Furthermore, it is proposed that the planetary gear be designed as a single-stage planetary gear. A "single-stage planetary gear" is understood to mean, in particular, a planetary gear that has a single sun gear and / or a single ring gear and / or a single set of planetary gears, which preferably lie on at least one plane. In particular, this is understood to mean a planetary gear in which a single transmission ratio can be realized.

[0008] The single-stage design of the planetary gear allows for a short and compact design of the drywall screwdriver in the axial direction. Furthermore, components, assembly effort, and assembly costs can be saved in a simple and advantageous way.

[0009] It is further proposed that the coupling element comprise at least one driving element, which is at least partially formed integrally with a planetary carrier element of the planetary gear set. A "planetary carrier element" is understood, in particular, to be an element intended to rotatably receive at least one planetary gear of the planetary gear set, wherein the at least one planetary gear is preferably rotatably received on the planetary carrier element via at least one bolt. The bolt can be formed by a component formed integrally with the planetary carrier element or, particularly advantageously, by a component formed separately from the planetary carrier element and attached to it.Furthermore, a "carrying element" should be understood in particular as an element intended to transmit at least one force and / or one movement across at least one surface to another element and / or to absorb a force and / or movement of another element. This allows for a particularly robust and cost-effective design of a transmission element with a coupling element.

[0010] Furthermore, it is proposed that the planetary carrier element be held directly in the housing via at least one bearing unit. A "bearing unit" is to be understood in particular as a unit that can absorb supporting forces in at least one direction and also enables relative movement between two components with low friction losses. Advantageously, this should be understood in particular as a plain bearing and / or, particularly advantageously, a rolling bearing; however, other bearing units that appear appropriate to a person skilled in the art are also conceivable. The plain bearing advantageously has a material pairing on a sliding surface that has a coefficient of friction, at least on the sliding surface, that is at least smaller than the coefficient of friction that arises when a material of the planetary carrier element and a material of the housing are paired.The term "direct" should be understood in particular to mean that the planetary carrier element is held in the housing via the at least one bearing unit without any intermediate gear and / or housing elements.

[0011] This advantageously allows for a small tolerance between the planetary carrier element and the housing unit. Furthermore, precise guidance of the gear unit can be achieved while requiring minimal installation space.

[0012] It is proposed that an axis of the output spindle and / or an axis of the gear unit correspond to an axis of the drive unit. An "axis" should be understood, in particular, as an axis along a main extension of a component and / or an axis of symmetry and / or an axis of rotation. This advantageously allows for a particularly compact design. Furthermore, it allows for an advantageous shape of the drywall screwdriver. Furthermore, an advantageous transmission of forces and torques can be achieved.

[0013] It is further proposed that the drywall screwdriver have at least one support element, different from a housing element, which at least partially surrounds a ring gear of the planetary gear. A "support element" is understood, in particular, to be an element designed to absorb and / or redirect forces from at least one direction. This advantageously allows forces to be transmitted without additional support forces acting on the ring gear. Furthermore, the ring gear can advantageously center the planetary gear unit.

[0014] It is further proposed that the output spindle be at least partially mounted and / or guided in the gear element of the gear unit. Preferably, the output spindle is at least partially mounted and / or guided in the planet carrier element of the planetary gear. This advantageously allows for a reduced number of components. Furthermore, high precision can be achieved. drawing

[0015] Further advantages will become apparent from the following description of the drawings. The drawings illustrate exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0016] They show: Fig. 1 shows a partial section of a drywall screwdriver according to the invention in a side view, Fig. 2 shows a planet carrier element of the drywall screwdriver according to the invention in a schematic representation and Fig. 3 shows a gear housing, a support element, a ring gear and a cover plate of the drywall screwdriver according to the invention in a schematic exploded view. Description of the embodiment

[0017] In Figure 1A partial section of a drywall screwdriver according to the invention is shown in a side view. The drywall screwdriver has a housing 10. The housing 10 includes a gear housing 56 and a motor housing 58. The gear housing 56 is manufactured in a pot design. The motor housing 58 is manufactured in a shell design. The drywall screwdriver also has a screw-in depth limiting element 12, a gear unit 14, an output spindle 16, a drive unit 18, and a clutch unit 20. The drive unit 18 is designed as a DC motor.

[0018] The screw-in depth limiting element 12 is arranged at an end of the gear housing 56 facing away from the motor housing 58, as viewed in an axial direction 62 of the gear housing 56. The screw-in depth limiting element 12 is detachably connected to the housing 10 of the drywall screwdriver by means of a plug-in connection. The screw-in depth limiting element 12 comprises an adjusting sleeve 66. In addition, the screw-in depth limiting element 12 comprises a depth stop 68. The depth stop 68 is provided to limit the screw-in depth of a screw during a screwing process. The adjusting sleeve 66 is provided to adjust the screw-in depth. Here, the screw-in depth is adjusted manually using the adjusting sleeve 66. To do this, an operator rotates the adjusting sleeve 66 about an axis that corresponds to an axis 38 of the output spindle 16. When the operator rotates the adjusting sleeve 66, the depth stop 68 is moved along the axial direction 62.

[0019] The adjusting sleeve 66 has an internal thread 70. The internal thread 70 extends over a partial area of an inner surface of the adjusting sleeve 66. The depth stop 68 has an external thread 72. The external thread 72 extends over a partial area of an outer surface of the depth stop 68. The external thread 72 of the depth stop 68 and the internal thread 70 of the adjusting sleeve 66 engage with each other when the screw-in depth limiting element 12 is in the assembled state. In the radial direction 74, viewed from the outside inwards, a spring element 76 is arranged in front of the depth stop 68. The spring element 76 presses the depth stop 68 inwards in the radial direction 74. The spring element 76 is arranged in a radially inner recess 78 of the adjusting sleeve 66. The radially inner recess 78 is arranged at an end of the adjusting sleeve 66 facing the depth stop 68 in the axial direction 62.The radially inner recess 78 secures the spring element 76 in the axial direction 62. The spring element 76 presses flanks of the external thread 72 of the depth stop 68 in the radial direction 74 against flanks of the internal thread 70 of the adjusting sleeve 66 in an area that lies opposite the spring element 76 in the radial direction 74. This creates friction between the flanks of the internal thread 70 and the external thread 72. This friction can reliably prevent automatic adjustment of the depth stop 68. In addition, the screw-in depth limiting element 12 has locking elements (not shown) that are provided for dividing the rotation of the adjusting sleeve 66 into individual locking steps. The locking elements can also reliably prevent automatic adjustment of the depth stop 68.

[0020] The adjustment sleeve 66 has a gripping area 80 arranged on an outer side of the adjustment sleeve 66. The gripping area 80 has lamellar elevations 82. The gripping area 80 is provided to increase the grip on the outer side of the adjustment sleeve 66 and thereby make it easier for the operator to rotate the adjustment sleeve 66.

[0021] The depth stop 68 has a stop surface 84, which rests against a surface of a machined workpiece when the screw reaches the screw-in depth set by the operator. The stop surface 84 has an annular cross-section.

[0022] The drywall screwdriver has a tool holder 86. The tool holder 86 is formed by a bit holder. The tool holder 86 has a magnetic element 88 for securely holding an insert tool (not shown) in the tool holder.

[0023] The tool holder 86 has a receiving area 90. The receiving area 90 is designed to receive the insert tool. The receiving area 90 has a hexagon socket contour (not shown in detail). When inserted, the insert tool is held in a rotationally fixed manner in the receiving area 90 of the tool holder 86.

[0024] The output spindle 16 is non-rotatably connected to the tool holder 86. The tool holder 86 is non-rotatably connected to the inserted tool and transfers the kinetic energy to the inserted tool.

[0025] During a screwing-in process, kinetic energy of the drive unit 18 is transferred to the output spindle 16 and thus to the tool holder 86 via the gear unit 14 and the coupling unit 20. The coupling unit 20 is provided to couple and / or decouple a torque transmission from the gear unit 14 to the output spindle 16. A gear element 22 of the gear unit 14 is fixedly connected to a coupling element 24 of the coupling unit 20. The gear element 22 of the gear unit 14 is formed integrally with the coupling element 24 of the coupling unit 20. The gear unit 14 comprises a planetary gear 26. The planetary gear 26 of the gear unit 14 is designed as a single stage. The gear unit 14 has a gear ratio between 3 and 10.

[0026] The coupling element 24 comprises three driving elements 30, 32, 34. The driving elements 30, 32, 34 are formed integrally with the planet carrier element 28 of the planetary gear 26.

[0027] The drive unit 18 comprises a motor spindle 92. In an operating state, the drive unit 18 generates a rotational movement of the motor spindle 92. A gear is arranged on the motor spindle 92. The gear forms a sun gear 94 of the planetary gear 26 of the gear unit 14. In an operating state, the sun gear 94 of the planetary gear 26 meshes with planet gears 96 of the planetary gear 26. In an operating state, the planet gears 96 each rotate about a rotational axis 98 of the planet gears 96. In addition, the planet gears 96 rotate about a rotational axis of the sun gear 94, which corresponds to an axis 42 of the gear unit 14. The axis 42 of the gear unit 14 corresponds to an axis 40 of the drive unit 18. The axis 38 of the output spindle 16 corresponds to the axis 40 of the drive unit 18. The rotation axis of the motor spindle 92 corresponds to the axis 40 of the drive unit 18.

[0028] The planetary gear 26 has a ring gear 46. In an operating state, the planet gears 96 mesh with the ring gear 46 of the planetary gear 26. The ring gear 46 of the planetary gear 26 is arranged in the gear housing 56 of the drywall screwdriver in a rotationally fixed manner relative to the housing 10 of the drywall screwdriver. The drywall screwdriver has a support element 44, which is different from a housing element and surrounds the ring gear 46 of the planetary gear 26. The support element 44 is arranged between the ring gear 46 and the housing 10. The support element 44 is received at its outer diameter in the gear housing 56 and the motor housing 58 without play. The support element 44 connects the gear housing 56 and the motor housing 58 in a sleeve-like manner. The support element 44 is formed by a connecting sleeve. The connecting sleeve is formed by a sheet metal sleeve. The support element 44 engages around the ring gear 46 of the planetary gear 26 with a radial and axial play.The ring gear 46 of the planetary gear 26 has at least one projection 48 in the axial direction 62. The projections 48 are formed on a side of the ring gear 46 facing the screw-in depth limiting element 12. The support element 44 has a collar 50 extending at least partially radially inward, with at least one recess 52. The collar 50 extends inward on a plane that runs orthogonal to the axial direction. Furthermore, the collar 50 has eight recesses 52. The projections 48 of the ring gear 46 engage through the recesses 52 of the collar 50 of the support element 44, into eight recesses 54 of the gear housing 56, whereby the ring gear 46 is fixed in the circumferential direction (see . Figure 3 ).

[0029] The planet carrier element 28 is supported directly in the housing via a bearing unit 36. The bearing unit 36 is pressed onto a radial outer surface of the planet carrier element 28. The bearing unit 36 is formed by a rolling bearing 102. The outer circumference of the bearing unit 36 rests directly on an inner surface of the transmission housing 56. The bearing unit 36 has axial play relative to the inner surface of the transmission housing 56. The bearing unit 36 is partially supported axially on the collar 50 of the support element 44. In the axial direction 62, the bearing unit 36 rests on the transmission housing 56 on a side facing the screw-in depth limiting element 12. On a side facing away from the screw-in depth limiting element, viewed in the axial direction 62, the bearing unit 36 rests on the collar 50 of the support element 44.When a force acts axially on the output spindle 16, the force can be transmitted via the coupling unit 20 to the planet carrier element 28. From the planet carrier element 28, the axial force can be transmitted to the bearing unit 36 via an effective pressure. The bearing unit 36 is supported in the axial direction 62 on the collar 50 of the support element 44, whereby an axial force is transmitted to the support element 44. The support element 44 is supported axially on a cover plate 60. The cover plate 60 is arranged in the motor housing 58. The cover plate 60 is held radially and axially in the motor housing 58 by means of a groove running circumferentially in the motor housing 58. As a result, an axial force can be redirected from the support element 44, via the cover plate 60, to the motor housing 58. Accordingly, a force acting axially on the output spindle 16 can be redirected to the motor housing 58.The ring gear 46 and the support element 44 are at least partially axially supported on the cover plate 60. The ring gear 46 and the support element 44 are axially supported on the cover plate 60 on a side facing away from the screw-in depth limiting element, as viewed in the axial direction 62.

[0030] The planet carrier element 28 has three recesses 104, 106, 108 on a side facing the drive unit 18. Three bolts 110 are guided through the three recesses 104, 106, 108. The three planet gears 96 are in turn mounted on the three bolts 110. Furthermore, the planet carrier element 28 has a recess 112 that runs axially to the axis 38 of the output spindle 16. The output spindle 16 is partially mounted and / or guided in the gear element 22 of the gear unit 14. The output spindle 16 is partially mounted and guided in the planet carrier element 28 of the planetary gear 26. The output spindle 16 is guided for axial movement in the recess 112. The planet carrier element 28 is provided to transmit the rotational movement of the planet gears 96 about the rotation axis of the sun gear 94 to the clutch unit 20.

[0031] On a side of the planet carrier element 28 facing the screw-in depth limiting element 12, a collar 114 is arranged around the recess 112. The three driving elements 30, 32, 34 of the first coupling element 24 are formed on the planet carrier element 28, radially spaced from the collar 114. The driving elements 30, 32, 34 have ramp-shaped runouts 116 on their surfaces facing in the circumferential direction (see Figure 2). The clutch unit 20 has, in addition to the first clutch element 24, a second clutch element 118 and a third clutch element 120. The second clutch element 118 has driving elements 122 on a side facing the first clutch element 24, as well as driving elements 124 on the side facing away from the first clutch element 24. The third clutch element 120 has driving elements 126 on a side facing the second clutch element 118. The driving elements 30, 32, 34, 122, 124, 126 each project out in the axial direction. In an operating state, the first clutch element 24 is driven in rotation directly by the gear unit 14 via the planetary carrier element 28. The second coupling element 118 is seated axially and circumferentially movable on the collar 114 of the planet carrier element 28 and is in engagement with the first coupling element 24. The third coupling element 120 is fixedly connected to the output spindle 16.

[0032] A spring element 128 is arranged between the second coupling element 118 and the third coupling element 120 in the axial direction 62. The spring element 128 is designed as a helical spring. The spring element 128 is provided to hold the second coupling element 118 and the third coupling element 120 in an unactuated state (as in Figure 1 shown) out of engagement. To do so, the spring element 128 presses the second coupling element 118 and the third coupling element 120 apart in the axial direction 62.

[0033] In an actuated state, the operator presses the drywall screwdriver against a workpiece in the axial direction 62. Due to the force exerted by an operator on the drywall screwdriver during a screwing-in process, the third coupling element 120 moves toward the second coupling element 118 against a spring force of the spring element 128. If contact occurs between the second coupling element 118 and the third coupling element 120, the second coupling element 118 is decelerated relative to the first coupling element 24. As a result, the second coupling element 118 is pushed onto the ramp-shaped runouts 116 of the first coupling element 24 and moved against the third coupling element 120, thereby assisting engagement.

[0034] The driving elements 30, 32, 34, 122, 124, 126 of the first clutch element 24, the second clutch element 118, and the third clutch element 120 are designed to bear against one another in an actuated state in a circumferential direction of the rotational movement of the gear unit 14. The driving elements 30, 32, 34 of the first clutch element 24 transmit the rotational movement of the gear unit 14 to the driving elements 122 of the second clutch element 118 and thus to the second clutch element 118. The driving elements 124 of the second clutch element 118 transmit the rotational movement of the gear unit 14 to the driving elements 126 of the third clutch element 120 and thus to the third clutch element 120.

[0035] Once the screw-in depth set by the operator is reached, the stop surface 84 of the depth stop 68 rests against a surface of the workpiece. In this state, the force in the axial direction 62 that the operator exerts on the drywall screwdriver is transmitted via the depth stop 68 to the workpiece, rather than to an insert tool. As a result, the third clutch element 120, which is loaded by the spring element 128, disengages from the second clutch element 118, so that the rotational movement of the gear unit 14 is no longer transmitted to the third clutch element 120 or to an insert tool.

Claims

1. Drywall screwdriver with a housing (10), with a screw-in depth limiting element (12), with a gear unit (14), with an output spindle (16), with a drive unit (18) and with a coupling unit (20) which is intended to couple and / or decouple a torque transmission of the gear unit (14) to the output spindle (16), characterized in that a gear element (22) of the gear unit (14) is fixedly connected to at least one coupling element (24) of the coupling unit (20).

2. Drywall screwdriver according to claim 1, characterized in that the gear element (22) of the gear unit (14) is at least partially formed in one piece with the at least one coupling element (24) of the coupling unit (20).

3. Drywall screwdriver according to one of the preceding claims, characterized in that the gear unit (14) comprises at least one planetary gear (26).

4. Drywall screwdriver according to claim 3, characterized in thatthe planetary gear (26) is designed as a single stage.

5. Drywall screwdriver at least according to claim 3, characterized in that the coupling element (24) comprises at least one driving element (30, 32, 34) which is at least partially formed in one piece with a planet carrier element (28) of the planetary gear (26).

6. Drywall screwdriver at least according to claim 3, characterized in that the planet carrier element (28) is held directly in the housing (10) via at least one bearing unit (36).

7. Drywall screwdriver according to one of the preceding claims, characterized in that an axis (38) of the output spindle (16) corresponds to an axis (40) of the drive unit (18).

8. Drywall screwdriver according to one of the preceding claims, characterized in that an axis (42) of the gear unit (14) corresponds to an axis (40) of the drive unit (18).

9. Drywall screwdriver at least according to claim 3, characterized byat least one support element (44) which differs from a housing element and is intended to at least partially encompass a ring gear (46) of the planetary gear (26).

10. Drywall screwdriver according to one of the preceding claims, characterized in that the output spindle (16) is at least partially mounted and / or guided in the gear element (22) of the gear unit (14).

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