Launching device, rope pulley assembly for a launching device and connecting spring for a rope pulley assembly

Description

[0001] The invention relates to a cable pulley assembly for a starter device for starting an internal combustion engine of a hand-held working device according to the preamble of claim 1 and a starter device with a cable pulley assembly.

[0002] US 2004 / 0177823 A1 discloses a starter device for starting an internal combustion engine. When starting the internal combustion engine, a pulley is set in rotation via a starter rope. The pulley is connected to a damping spring, by means of which the rotational energy of the pulley is transferred to the crankshaft of an internal combustion engine.

[0003] WO 2015 / 072900 A1 discloses a cable pulley with a spring receptacle in which a connecting spring is accommodated. A spiral recess is formed on the peripheral edge of the cable pulley, in which a starter cable is wound. The spring receptacle and the recess overlap both in the axial direction of the rotation axis and in the radial direction.

[0004] US Pat. No. 3,858,566 A also discloses a pulley with a spiral recess connected to a return spring. The recess overlaps the return spring in both the axial and radial directions.

[0005] The invention is based on the object of creating a cable pulley assembly with a compact design.

[0006] This object is achieved by a pulley assembly having the features of claim 1.

[0007] A further object of the invention is to further develop a starter device with a pulley assembly such that the starter device is designed to be compact.

[0008] This object is achieved by a starting device having the features of claim 8.

[0009] For the cable pulley assembly according to the invention, it is provided that the spring mount of the cable pulley and the circumferential recess for receiving a starter cable in the outer circumferential side of the cable pulley overlap both in the axial direction of the rotation axis and in the radial direction of the rotation axis. This makes it possible to save installation space, particularly in the axial and / or radial directions, and to design the cable pulley assembly compact. The cable pulley assembly according to the invention for a starter device for starting an internal combustion engine of a hand-held implement can be designed such that it takes up little installation space in the hand-held implement, allowing the hand-held implement to be designed compactly. This makes the hand-held implement easy to guide and enables comfortable work for the operator.Furthermore, a more compact design, particularly in the radial direction, can improve the cooling air supply to the combustion engine.

[0010] According to the invention, the spring receptacle comprises a spring chamber and a suspension area for connection to the connecting spring, and the suspension area of ​​the spring receptacle and the recess for receiving the starter cable are arranged at least partially adjacent to one another in the axial direction. As a result, the first end of the connecting spring, when suspended in the suspension area, is arranged radially far outwards. When the cable pulley rotates about its axis of rotation, a large torque can be transmitted from the cable pulley to the connecting spring. Furthermore, the extension of the spring receptacle, in particular of the spring chamber, can be large in the radial direction. This allows the installation of large connecting springs. Such springs can transmit large forces.Because the recess in the pulley begins radially inside the spring mount, rather than radially outside as is typical in the prior art, more rope can be accommodated on the pulley with the same pulley diameter. This makes it possible to reduce the pulley diameter while keeping the accommodated rope volume constant. Reducing the pulley diameter allows air to penetrate the starter housing more easily, thus improving cooling of the combustion engine.

[0011] In particular, the suspension area of ​​the spring receptacle has a width measured in the axial direction. In particular, the spring chamber of the spring receptacle has a width measured in the axial direction. The width of the suspension area is advantageously less than 100%, in particular less than 70%, preferably less than 65% of the width of the spring chamber. This allows the connecting spring with its suspension area to be arranged in a space-saving manner in the axial direction next to the recess for receiving the starter cable, while still having a sufficient width to ensure the required stability of the connecting spring.

[0012] In particular, the pulley has a maximum width measured in the axial direction. Advantageously, the width of the recess for accommodating the starter cable, measured in the axial direction on the circumferential side of the pulley, is at least 15%, in particular at least 25%, of the maximum width of the pulley. Thus, the recess provides sufficient space in the axial direction to accommodate the starter cable.

[0013] According to the invention, the connecting spring is suspended with its first end in the suspension area of ​​the spring receptacle and has a maximum width measured in the axial direction. A width of the connecting spring at its first end, measured in the axial direction, is smaller than the maximum width of the connecting spring. The width of the connecting spring at its first end, measured in the axial direction, is in particular smaller than 75%, preferably smaller than 65% of the maximum width of the connecting spring. This makes it possible to accommodate the first end of the connecting spring in a space-saving manner in a suspension area that is comparatively small in the axial direction and, at the same time, to design the spring to be sufficiently stable. It has been shown that spring breakages of the connecting spring generally occur away from their ends.For this reason, the first end of the connecting spring can be designed to be narrower, and the connecting spring can be designed to be sufficiently wide between its ends for high stability.

[0014] The connecting spring is expediently narrower in the circumferential direction around the rotational axis within an angular range of at least 10°, in particular at least 15°, at its first end than the maximum width of the connecting spring. The term "first end of the connecting spring" refers here to an end region of the connecting spring that extends over an angular range of the spring, not just a discrete point. Due to the narrower design of the connecting spring at its first end, a suspension extension at the first end of the connecting spring can be designed sufficiently long in the circumferential direction to establish a secure connection to the cable pulley while simultaneously taking up minimal space in the axial direction.

[0015] In an advantageous development of the invention, the cable pulley has an air guide contour on its circumferential side. Typically, the cable pulley assembly is arranged on the crankshaft of an internal combustion engine such that a fan wheel for conveying cooling air to the cylinder is located between the cable pulley assembly and a cylinder of the internal combustion engine. As the cooling air is conveyed to the cylinder, the air flows past the cable pulley assembly on its way from the outside of the hand-held tool to the cylinder of the internal combustion engine. The air guide contour can positively influence the course of the air flow. Flow resistance can be reduced, and the cooling air can be directed past the cable pulley.

[0016] Preferably, the air guide contour is designed in such a way that the cooling air flow cannot reach components sensitive to contamination, such as the connecting spring.

[0017] For practical purposes, the air guide contour of the pulley is concave in a section along the rotation axis. This allows for better air flow to the impeller and cylinder, while also protecting the connecting spring of the pulley assembly from the ingress of contaminants from the cooling air.

[0018] The connecting spring is advantageously a spiral spring.

[0019] For the starter device according to the invention with a pulley assembly, it is provided that the starter device comprises a coupling device for connecting the pulley to a crankshaft of the internal combustion engine and that a second end of the connecting spring of the pulley assembly is connected in a rotationally fixed manner to the coupling device.

[0020] The coupling device is advantageously a carrier. The carrier completely covers the spring chamber in the axial direction. This protects the spring chamber and, in particular, the connecting spring from contamination, particularly from the cooling air flow. This makes the connecting spring less susceptible to failure and largely maintenance-free.

[0021] In an advantageous development of the invention, the coupling device comprises coupling means for coupling the starter device to the crankshaft of the internal combustion engine, the driver comprises an air guide collar, and the air guide collar is arranged on a side of the driver facing away from the connecting spring in the axial direction. Advantageously, the air guide collar is arranged radially outside the coupling means. The air guide collar can thus protect the coupling means from contaminants from the cooling air flow. This enables a largely trouble-free coupling of the driver via its coupling means to the crankshaft of the internal combustion engine.

[0022] The air guide collar is advantageously conical in at least one section along the rotational axis. This allows the cooling air flow to be conveyed to the fan wheel in a particularly advantageous manner.

[0023] The width of the connecting spring according to the invention at its first end is smaller than the maximum width of the connecting spring. The width of the connecting spring according to the invention at its first end is in particular smaller than 75%, preferably smaller than 65%, of the maximum width of the connecting spring. As already described above, this makes the connecting spring stable and, at the same time, allows it to be connected to a cable pulley while saving installation space.

[0024] An embodiment of the invention is explained below with reference to the drawings. They show: Fig. 1 an exploded view of a starting device, Fig. 2 a partial schematic representation of a section through the starting device from Fig. 1 on a working device, Fig. 3 a perspective view of a pulley assembly of the starter device according to Fig. 1 , Fig. 4 a section through the pulley assembly from Fig. 3 with starter rope, Fig. 5 a perspective view of a connecting spring of the pulley assembly according to Fig. 1 , Fig. 6a side view of the connecting spring according to Fig. 5 , Fig. 7 a perspective view of a driver of the starting device according to Fig. 1 , Fig. 8 a schematic representation of a section through the pulley assembly and the driver from Fig. 1 , Fig. 9a side view of the pulley assembly and the driver from Fig. 8 , Fig. 10 a perspective view of a connecting spring of the pulley assembly according to Fig. 1 and Fig. 11 a schematic representation of a hand-held working device with a starting device.

[0025] Fig. 11 shows a hand-held implement 40, in the exemplary embodiment a motor-driven chainsaw. The hand-held implement can also be another hand-held implement, for example a blower, a brush cutter, a cut-off grinder, or the like. The implement 40 has a housing 46 in which a schematically illustrated internal combustion engine 42 is arranged. The internal combustion engine 42 is preferably a single-cylinder engine, in particular a two-stroke engine or a mixture-lubricated four-stroke engine. The internal combustion engine 42 serves to drive a tool. In the exemplary embodiment, the tool is a saw chain 44 driven in rotation around a guide rail 43. A handle 45 and a handle tube 47 serve to guide the implement 40. A starter device 1 is provided for starting the internal combustion engine 42, which in Fig. 11 is also shown schematically. The starting device 1 is preferably a manually operated pull-cord starter. The starting device 1 comprises a starter handle 41 that protrudes from the housing 46 of the working device 40.

[0026] In Fig. 1 The starter device 1 is shown in detail. The starter device 1 comprises a starter housing 24, a return spring 23, a cable pulley assembly 20, and a coupling device 6. The starter housing 24 advantageously forms part of the housing 46 of the hand-held implement 40.

[0027] The cable pulley assembly 20 consists of a cable pulley 2 and a connecting spring 9. The starter housing 24 has a bearing pin 25. The cable pulley 2 and the coupling device 6 are rotatably mounted on the bearing pin 25. For this purpose, the cable pulley 2 has a hub 3. The bearing pin 25 is inserted through the hub 3. The cable pulley 2 is connected to the starter housing 24 via the return spring 23. In the exemplary embodiment, the return spring 23 is a spiral spring. The return spring 23 is arranged between the starter housing 24 and the cable pulley 2 in a return spring receptacle 38 of the cable pulley 2 and is connected at one end to the starter housing 24 and at its other end to the cable pulley 2 in a rotationally fixed manner. The cable pulley 2 is connected to the coupling device 6 via the connecting spring 9. The connecting spring 9 is a spiral spring. The connecting spring 9 is arranged between the cable pulley 2 and the coupling device 6 in a spring holder 8 of the cable pulley 2.The connecting spring 9 is arranged on the side of the cable pulley 2 facing away from the starter housing 24.

[0028] The starting device 1 is used to start the Fig. 2 shown combustion engine 21. On the pulley 2 is a Fig. 2 The starter cable 26 shown is wound up. A first end of the starter cable 26 is fixed to the cable pulley 2. A second end of the starter cable 26 is led out of the starter housing 24 through a starter connection 27 of the starter housing 24. To start the internal combustion engine 21, the operator pulls the starter handle 41 ( Fig. 11 ), which is fixed to the second end of the starter cable 26. The pull on the starter cable 26 sets the cable pulley 2 in rotation about an axis of rotation 50. The cable pulley 2 rotates about the bearing pin 25. The axis of rotation 50 extends in an axial direction 100. The axial direction 100 runs from the return spring holder 38 of the cable pulley 2 in the direction of the spring holder 8 for receiving the connecting spring 9. The axial direction 100 runs from the cable pulley 2 in the direction of the connecting spring 9. A radial direction 90 extends perpendicular to the axis of rotation 50. The rotational energy of the cable pulley 2 is transferred to the coupling device 6 via the connecting spring 9. The connecting spring 9 serves to dampen jerky and uneven pulling movements.The connecting spring can also be designed to temporarily store energy, allowing the connecting spring to be tensioned by several pulls on the starter cable before the connecting spring releases its stored energy to the crankshaft via the coupling device. In this case, the connecting spring is typically connected to the pulley via a freewheel.

[0029] The coupling device 6 has coupling means 17. In the exemplary embodiment, the coupling device 6 is a driver 15. The coupling means 17 are designed as locking projections on a peripheral region of the driver 15. It can also be provided that the coupling means of the coupling device of the starter device are pawls.

[0030] The internal combustion engine 21 has a crankshaft 18. A fan wheel 28 is connected to the crankshaft 18 in a rotationally fixed manner. The fan wheel 28 engages over the coupling means 17 of the coupling device 6 of the starter device 1 with a cup-shaped projection. Coupling means 22 of the crankshaft 18 are pivotally mounted on this head-shaped projection. In the exemplary embodiment, the coupling means 22 of the crankshaft 18 are pawls. However, it can also be provided that the coupling means of the crankshaft are locking projections or the like. In the exemplary embodiment, the coupling means 22 of the crankshaft 18 are preloaded by springs in the direction of the coupling means 17 of the coupling device 6 of the starter device 1.

[0031] When the starter cable 26 is pulled, the coupling device 6 of the starter mechanism 1 is set in rotation and, via the coupling means 17 of the coupling device 6, designed as locking projections, engages the coupling means 22 of the crankshaft 18, designed as pawls. This causes the impeller 28 and thus the crankshaft 18 to rotate. If the crankshaft 18 rotates faster than the driver 15, the coupling means 22 lose their contact with the coupling means 17, designed as locking projections, of the starter mechanism 1. At this point in time, the starting process is already complete, and the crankshaft 18 is driven by the combustion engine 21.

[0032] The rotation of the pulley 2 during the starting stroke also tensions the return spring 23. After the starter stroke is completed, the pulley 2 is rotated by the return spring 23 in the opposite direction of its rotation when the starter cable 26 is pulled, and the starter cable 26 is wound back onto the pulley 2.

[0033] Fig. 3 shows the cable pulley assembly 20. The connecting spring 9 of the cable pulley assembly 20 is connected to the cable pulley 2 of the cable pulley assembly 20 in a rotationally fixed manner at a first end 12. For this purpose, the connecting spring 9 has a suspension extension 13 at its first end 12. In this context, "first end" refers to a specific area with respect to a circumferential direction 80. The circumferential direction 80 extends in the direction around the rotation axis 50.

[0034] The cable pulley 2 has the spring receptacle 8 for receiving the connecting spring 9. The spring receptacle 8 comprises a spring chamber 11 and a suspension area 10. The suspension area 10 of the spring chamber 11 serves to connect the cable pulley 2 with the connecting spring 9. The suspension area 10 is arranged further away from the rotation axis 50 in the radial direction 90 than the spring chamber 11. As in Fig. 3 As shown, the connecting spring 9 is suspended with its suspension extension 13 in the suspension area 10 of the spring holder 8 of the cable pulley 2. The suspension extension 13 is also shown in Fig. 1 The suspension extension 13 is bent in the exemplary embodiment opposite to the winding direction of the connecting spring 9, i.e. in the circumferential direction 80. The suspension extension 13 forms part of the first end 12 of the connecting spring 9. The connecting spring 9 comprises a base body 32 and the suspension extension 13. The first end of the connecting spring 9 is located on the outside in the radial direction 90. The suspension extension 13 is U-shaped in the exemplary embodiment in a view in the axial direction 100. This is also shown in Fig. 6 The suspension extension 13 can also be angled in a different form from the base body 32. As can be seen from the Fig. 1 and 3As can be seen, the shape of the suspension area 10 of the spring receptacle 8 is adapted to the shape of the suspension extension 13 of the connecting spring 9. Accordingly, the shape of the suspension area 10 of the spring receptacle 8 is essentially L-shaped when viewed opposite the axial direction 100. In the circumferential direction 80, next to the suspension area 10, a receiving space 39 is provided for a knot at the first end of the starter cable 26. The knot of the starter cable 26 and the suspension extension 13 of the connecting spring 9 have essentially the same radial distance from the rotation axis 50.

[0035] As in Fig. 1 As shown, the connecting spring 9 has a second end 19. The second end 19 of the connecting spring 9 lies inward in the radial direction 90. The second end 19 of the connecting spring 9 of the cable pulley assembly 20 is connected in a rotationally fixed manner to the coupling device 6. For this purpose, the driver 15 has a receptacle for the second end 19, designed in a known manner but not shown.

[0036] As in Fig. 3 As shown, the cable pulley 2 has, in its outer circumferential side 4 located in the radial direction 90, a circumferential recess 5 for receiving the starter cable 26. The recess 5 has a recess bottom 29 and recess side walls 30 and 31 opposite one another in the axial direction 100. The recess 5 runs completely around the axis of rotation 50.

[0037] Fig. 4 shows a section through the cable pulley assembly 20 with the starter cable 26 wound on the cable pulley 2. The section plane contains the axis of rotation 50 of the cable pulley 2 and the suspension extension 13 of the connecting spring 9. The spring receptacle 8 and the recess 5 overlap both in the axial direction 100 and in the radial direction 90. The recess 5 and the spring receptacle 8 lie in a common first plane running perpendicular to the axis of rotation 50. The recess 5 and the spring receptacle 8 lie in a common second plane running perpendicular to the radial direction 90. The first plane and the second plane are perpendicular to one another. The spring receptacle 8 and the recess 5 are arranged at the same height both in the axial direction 100 and at the same height in the radial direction 90.

[0038] The suspension area 10 of the spring receptacle 8 and the recess 5 for receiving the starter cable 26 overlap in the axial direction 100. The suspension area 10 and the recess 5 are arranged at least partially adjacent to one another in the axial direction 100. The spring chamber 11 and the recess 5 overlap in the radial direction 90. The spring chamber 11 and the recess 5 are arranged at least partially adjacent to one another in the radial direction 90.

[0039] The suspension area 10 has a width b1 measured in the axial direction 100. The spring chamber 11 has a width b2 measured in the axial direction 100. The width b1 of the suspension area 10 is smaller than the width b2 of the spring chamber 11. The width b1 of the suspension area 10 is smaller than 70% of the width b2 of the spring chamber 11. In the exemplary embodiment, the width b1 of the suspension area 10 is smaller than 65% of the width b2 of the spring chamber 11.

[0040] The cable pulley 2 has a maximum width b3 measured in the axial direction 100. The recess 5 has a width b4 measured on the circumferential side 4 of the cable pulley 2 in the axial direction 100. The width b4 of the recess 5 is at least 15% of the maximum width b3 of the cable pulley 2. In the exemplary embodiment, the width b4 of the recess 5 is at least 25% of the maximum width b3 of the cable pulley 2.

[0041] The width b1 of the suspension area 10 is at least 25% of the maximum width b3 of the rope pulley 2.

[0042] The connecting spring 9 has a maximum width b5 measured in the axial direction 100. The connecting spring 9 has a width b6 measured at its first end 12 in the axial direction 100. In the exemplary embodiment, the width b6 of the connecting spring 9 is measured at its first end 12 in the region of the suspension extension 13. The width b6 of the connecting spring 9 at its first end 12 is smaller than the maximum width b5 of the connecting spring 9. The width b6 of the connecting spring 9 at its first end 12 is smaller than 75% of the maximum width b5 of the connecting spring 9 in the region of the suspension extension 13. In the exemplary embodiment, the width b6 of the connecting spring 9 at its first end 12 in the region of the suspension extension 13 is smaller than 65% of the maximum width b5 of the connecting spring 9.

[0043] The suspension extension 13 has a width b7 measured in the axial direction 100. The width b7 of the suspension extension 13 is smaller than the maximum width b5 of the connecting spring 9. The width b7 of the suspension extension 13 is smaller than 75% of the maximum width b5 of the connecting spring 9. In the exemplary embodiment, the width b7 of the suspension extension 13 is smaller than 65% of the maximum width b5 of the connecting spring 9.

[0044] As in Fig. 6 As shown, the connecting spring 9 is advantageously narrower in the circumferential direction 80 in an angular range α of at least 5° around the axis of rotation 50 than the maximum width b5 of the connecting spring 9. In the exemplary embodiment, the connecting spring 9 is narrower in the circumferential direction 80 in the angular range α of at least 10° than the maximum width b5 of the connecting spring 9.

[0045] As in Fig. 4 As shown, the connecting spring 9 has a maximum radial extension a measured in the radial direction 90, starting from the rotation axis 50. From the overview of the Fig. 1 and 4 It follows that the suspension extension 13 extends in the radial direction 90 over at least 10% of the largest radial extent a of the connecting spring 9. In the exemplary embodiment, the suspension extension 13 extends in the radial direction 90 over at least 15% of the largest radial extent a of the connecting spring 9.

[0046] As in Fig. 4 As shown, the suspension extension 13 of the connecting spring 9 is arranged in the axial direction 100 next to the starter cable 26. In addition to the suspension extension 13, the connecting spring 9 has the base body 32. The base body 32 is located closer to the axis of rotation 100 in the radial direction 90 than the suspension extension 13. The base body 32 of the connecting spring 9 is arranged in the spring chamber 11 of the spring receptacle 8. The recess 5 runs around the base body 32 of the connecting spring 9. The recess 5 encloses the base body 32 of the connecting spring 9. The base body 32 of the connecting spring 9 and the starter cable 26 in the recess 5 are arranged next to one another in the radial direction 90.

[0047] As in Fig. 4 As shown, the cable pulley 2 has an air guiding contour 14 on its circumferential side 4. The circumferential side 4 of the cable pulley 2 runs in the circumferential direction 80 around the axis of rotation 50. The air guiding contour 14 is advantageously concave in a section along the axis of rotation 50. This means that the air guiding contour 14 is concave in a direction perpendicular to the axis of rotation 50 when viewed from outside the cable pulley 2. The air guiding contour is concave 90° opposite to the radial direction when viewed from outside the cable pulley 2.

[0048] The cable pulley 2 has a first outer surface 33 and a second outer surface 34 in the axial direction 100. The first outer surface 33 and the second outer surface 34 form end faces of the cable pulley 3 facing away from each other with respect to the axial direction 100. The first outer surface 33 faces away from the connecting spring 9. The second outer surface 34 faces the connecting spring 9. The second outer surface 34 lies adjacent to the suspension area 10 of the spring receptacle 8 in the axial direction 100, and the first outer surface 33 lies adjacent to the recess 5 of the cable pulley 2 in the axial direction 100. The air guiding contour 14 extends in the circumferential side 4 of the cable pulley 2 up to the second outer surface 34 of the cable pulley 2. The air guiding contour 14 of the cable pulley 2 runs almost completely around the axis of rotation 50. As in Fig. 3 As shown, the air guide contour 14 is interrupted in the circumferential direction 80 only by the suspension area 10 of the spring retainer 8 and the receiving space 39 for the knot of the starter cable 26. The suspension area 10 and the receiving space 39 are located directly adjacent to one another in the circumferential direction 80 and form a common circumferential section. The air guide contour 14 is interrupted in the circumferential direction 80 only at this one common circumferential section.

[0049] The Figuren 5 and 10 show the connecting spring 9 in a schematic, perspective view. From the overview of the Fig. 5 und 6 It can be seen that the connecting spring 9 in the exemplary embodiment has the maximum width b5 in the area of ​​its base body 32, except in the angular range α. At its first end 12, between the area of ​​the base body 32 with maximum width b5 and the suspension extension 13, the connecting spring 9 has a transition surface 35. The width of the connecting spring 9 in the area of ​​the transition surface 35 increases, starting from the suspension extension 13 up to the area of ​​the base body 32 of the connecting spring 9 with maximum width b5, with respect to the circumferential direction 80. In particular, the width of the connecting spring 9 increases continuously in the area of ​​the transition surface 35. The increase can be linear or non-linear. In the exemplary embodiment, the increase is non-linear, as in Fig. 10 The transition surface 35 connects the area of ​​the base body 32 of the connecting spring 9 with maximum width b5 with the suspension extension 13 of the connecting spring 9. It may be expedient to also provide a change in the width of the connecting spring 9 at the inner, second end 19 of the connecting spring 9.

[0050] Fig. 7 shows the driver 15 in a perspective view. The driver 15 has an air guide collar 16. As in Fig. 1 As shown, the air guide collar 16 is arranged on a side of the driver 15 facing away from the connecting spring 9. The air guide collar 16 is arranged outside the coupling means 17 in the radial direction 90.

[0051] Fig. 8 shows a section through the pulley assembly 20 with the driver 15 arranged on the pulley assembly 20. The section plane includes the rotation axis 50.

[0052] The contour 36 of the air guide collar 16 is shown with a dashed line. The contour 36 of the air guide collar 16 runs conically in a section along the rotation axis 50. In this case, the driver tapers in the axial direction 100. It can also be provided that the contour of the air guide collar runs concavely in a section along the rotation axis 50, at least in one section. Such a profile is shown under the reference numeral 37 with a dashed line in Fig. 8 marked.

[0053] The driver 15 completely covers the spring chamber 11 of the spring holder 8 in the axial direction 100. The suspension area 10 of the spring holder 8 advantageously projects at least partially in the radial direction 90 beyond the driver 15. This is also shown in Fig. 9 shown.

Claims

1. Rope-pulley assembly for a starting apparatus for starting a combustion engine of a hand-held implement, comprising a rope pulley (2) and a connecting spring (9), wherein a first end (12) of the connecting spring (9) is connected in a rotationally conjoint manner to the rope pulley (2), wherein the rope pulley (2) has an axis of rotation (50) extending in an axial direction (100), wherein the rope pulley (2) has in its circumferential side (4) situated at the outside in a radial direction (90) an encircling depression (5) for receiving a starting rope (26), and wherein the rope pulley (2) has a spring receptacle (8) for receiving the connecting spring (9), wherein, when seen both in the axial direction (100) and in the radial direction (90), the spring receptacle (8) and the depression (5) overlap, wherein the spring receptacle (8) comprises a spring chamber (11) and a fitting region (10) for connection to the connecting spring (9), wherein the fitting region (10) and the depression (5) are arranged so as to be situated adjacent to one another at least partially in the axial direction (100), wherein the connecting spring (9) is fitted by way of the first end (12) into the fitting region (10) of the spring receptacle (8), wherein the connecting spring (9) has a maximum width (b5) measured in the axial direction (100), characterized in that a width (b6), measured in the axial direction (100), of the connecting spring (9) at the first end (12) thereof is less than the maximum width (b5) of the connecting spring (9).

2. Rope-pulley assembly according to Claim 1, characterized in that the fitting region (10) has a width (b1) measured in the axial direction (100), in that the spring chamber (11) has a width (b2) measured in the axial direction (100), and in that the width (b1) of the fitting region (10) is less than 100%, in particular less than 70%, preferably less than 65%, of the width (b2) of the spring chamber (11).

3. Rope-pulley assembly according to Claim 2, characterized in that the rope pulley (2) has a maximum width (b3) measured in the axial direction (100), and in that a width (b4), measured in the axial direction (100) on the circumferential side (4) of the rope pulley (2), of the depression (5) is at least 15%, in particular at least 25%, of the maximum width (b3) of the rope pulley (2).

4. Rope-pulley assembly according to one of Claims 1 to 3, characterized in that, at its first end (12), the connecting spring (9) is narrower than the maximum width (b5) of the connecting spring (9) in an angular range (α) of at least 5°, in particular of at least 10°, in the circumferential direction (80) about the axis of rotation (50).

5. Rope-pulley assembly according to one of Claims 1 to 4, characterized in that the rope pulley (2) has an air-guiding contour (14) on its circumferential side (4).

6. Rope-pulley assembly according to Claim 5, characterized in that the air-guiding contour (14) is concave in a section along the axis of rotation (50).

7. Rope-pulley assembly according to one of Claims 1 to 6, characterized in that the connecting spring (9) is a spiral spring.

8. Starting apparatus having a rope-pulley assembly according to one of Claims 1 to 7, characterized in that the starting apparatus (1) comprises a coupling device (6) for connecting the rope pulley (2) to a crankshaft (18) of the combustion engine (21), and in that a second end (19) of the connecting spring (9) of the rope-pulley assembly (20) is connected in a rotationally conjoint manner to the coupling device (6).

9. Starting apparatus according to Claim 8, characterized in that the coupling device (6) is a driver (15).

10. Starting apparatus according to Claim 8 or 9, characterized in that the driver (15) completely covers the spring chamber (11) in the axial direction (100).

11. Starting apparatus according to one of Claims 8 to 10, characterized in that the coupling device (6) comprises coupling means (17) for coupling the starting apparatus (1) to the crankshaft (18) of the combustion engine (21), in that the coupling device (6) comprises an air-guiding collar (16), in that the air-guiding collar (16) is arranged on a side of the coupling device (6) that faces away from the connecting spring (9), and in that the air-guiding collar (16) is arranged radially outside the coupling means (17).

12. Starting apparatus according to Claim 11, characterized in that the air-guiding collar (16) is conical at least in one portion in a section along the axis of rotation (50).

13. Rope-pulley assembly according to one of Claims 1 to 7 or starting apparatus according to one of Claims 8 to 12, characterized in that the width (b6), measured in the axial direction (100), of the connecting spring (9) at its first end (12) is less than 75% of the maximum width (b5) of the connecting spring (9).

14. Rope-pulley assembly or starting apparatus according to Claim 13, characterized in that the width (b6), measured in the axial direction (100), of the connecting spring (9) at its first end (12) is less than 65% of the maximum width (b5) of the connecting spring (9).