ELECTRICAL STARTER SYSTEM FOR THE RETROFIT OF MOTORCYCLES

Abstract

An electrical starter system and construction kit for retrofitting Harley-Davidson motorcycles built from 1936 to 1957 with a mechanical starting device. The starter system includes a clutch device that can be coupled to the transmission main shaft for transmitting rotary motion having at least one starter gearwheel, a clutch hub, a clutch cage that can be or is attached to the hub for transmitting a rotary motion and an electrical starter motor with a starter shaft pinion that can be driven by the electrical motor for engaging the starter gearwheel. The starter gearwheel is or can be mechanically coupled to the clutch hub for transmitting a rotary motion to the hub. Preferably, a gearwheel/hub adapter is disposed between and couples the clutch hub and the starter gearwheel. The adapter is or can be coupled to the starter gearwheel and the clutch hub and is or can be coupled to a transmission main shaft of the motorcycle.

Claims

1. An electrical starter system, particularly an electrical starter construction kit for the retrofit of motorcycles of the Harley-Davidson brand built from 1936 to 1957 with a mechanical starting device, which starter system includes the following: a clutch device (89) that can be coupled to the transmission main shaft (2) of the motorcycle for transmitting rotary motion, having at least one starter gearwheel (8), a clutch hub (4) and a clutch cage (91) that can be or is attached to the latter for transmitting a rotary motion; furthermore an electrical starter motor (32) with a starter shaft pinion (24) that can be driven by the electrical starter motor (32) for engaging in the starter gearwheel (8) of the clutch device (89), characterized in that the starter gearwheel (8) is or can be mechanically coupled to the clutch hub (4) for transmitting a rotary motion to the clutch hub (4).

2. The starter system according to claim 1, characterized in that the coupling is implemented by welding or another positive, frictional, or cohesive connection or adaptation.

3. The starter system according to claim 1, characterized in that a gearwheel/hub adapter (6) is disposed between the clutch hub (4) and the starter gearwheel (8) for coupling the same to one another, which adapter is or can be coupled in a rotationally rigid manner to the starter gearwheel (8) and the clutch hub (4), and is connected or can be coupled in a rotationally rigid manner to a transmission main shaft (2) of the motorcycle.

4. The starter system according to claim 3, characterized in that the adapter (6) is implemented with an annular disc (6a) from whose inner edge or end face one or more projections (6b) extend towards the clutch hub (4) whose inner diameter (4a) is adapted to the projection(s) (6b) (6b) complementary to the frictional, form-fitting, or cohesive engagement.

5. The starter system according to claim 3, characterized by one or more driving elements (6c) configured in the adapter (6) which are disposed for torque-transmitting engagement with the transmission main shaft (2) of the motorcycle.

6. The starter system according to claim 1, characterized in that the starter gearwheel (8) is arranged or its outer diameter is dimensioned such that it can be covered by an outer primary cover or a primary drive gearbox of the motorcycle.

7. The starter system according to claim 1, characterized by an output pinion (82) that can be mounted to the crankshaft (83) of the motorcycle and is designed with a projection or extension of such thickness and orientation that an offset of the primary chain drive (84) on the transmission main shaft (2) of the motorcycle is compensated by said thickness and orientation such that the primary chain drive (84) of the motorcycle is flush in a plane corresponding to the offset.

8. The starter system according to claim 1, wherein a first or bottom holding part (12) and a second or top holding part (18) are provided for fastening the starter motor (33) to a motorcycle frame (85) or transmission base plate (97) of the motorcycle, wherein the first holding part (12) is configured for connecting to the motorcycle frame (85), the second holding part (18) is configured for connecting to the starter motor (33), and both holding parts (12, 18) are configured for connecting to one another, characterized in that the bottom or first holding part (12) is a plate-like holding element for flat support on, and connection to, the motorcycle frame (85) or the transmission base plate (97) of the motorcycle, wherein a fastening projection associated with the second holding part (18) projects away from a free flat side of the plate-like holding element of the first holding part (12), having an extension of 20% to 90% of the longitudinal dimension of the holding element (12).

9. The starter system according to claim 8, characterized in that the first or second holding part (12, 18) is/are produced as cast parts or made by iron casting.

10. The starter system according to claim 8, characterized in that the first holding part and the second holding part connected to it (12, 18) are configured for being mounted to a position that is located on the retrofitted motorcycle perpendicular to the longitudinal axis in the direction of travel between the starter motor (32) and a gearwheel of a secondary drive (92) of the motorcycle.

11. The starter system according to claim 1, having a magnetic switch (34), characterized in that the electric motor (32) and the magnetic switch (34) are arranged one below the other.

12. The starter system according to claim 1, characterized by a battery support device (71) for bottom-gripping or supporting the battery (74) of the motorcycle, wherein the battery support device (71) is adjusted to prevent a mechanical collision with the top holding part (18) or the starter motor casing (33).

13. The starter system according to claim 1, characterized by a chain tensioning device (50) configured for fastening to the transmission base plate (97) or to a crankshaft casing (81) of the motorcycle for retensioning the primary chain (84).

14. A motorcycle equipped, retrofitted, or provided with an electrical starter system according to any one of the preceding claims.

Description

BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS

[0025] Further details, features, feature combinations, effects and advantages of the invention can be derived from the following description of the invention and the drawings. Wherein

[0026] FIG. 1 is a perspective exploded view showing the assembly of the starter gear on the clutch hub

[0027] FIG. 2 is a partial perspective exploded view of the starter construction kit with starter motor and brackets

[0028] FIG. 3 is a perspective view of the modified battery bracket according to the invention with the battery installed

[0029] FIG. 4 is a lateral perspective view of the primary chain drive as built from 1955 to 1957

[0030] FIG. 5 is a lateral view of a Harley-Davidson motorcycle as built from 1936 to 1954

[0031] FIG. 6 is a cross sectional view of the electrical starter perpendicular to the longitudinal axis in the direction of travel of a Harley-Davidson motorcycle as built from 1936 to 1957

[0032] The cover as part of the primary drive gearbox is not shown in any of the drawings for the sake of clarity.

DETAILED DESCRIPTION

[0033] According to FIG. 1, the modified clutch hub 4 is seated on the transmission main shaft 2. The clutch hub 4 is an original component of Harley-Davidson processed within the meaning of the invention such that its cylindrical diameter 4a is concentrically enlarged (not shown). The gearwheel adapter 6, consisting of an annular disc 6a and a projection 6b seated on said annular disc 6a in the direction of the clutch hub 4, follows in positive fit with the clutch hub 4. The adapter 6 can be slid into the clutch hub 4 until it reaches the annular disc 6a. The adapter 6 itself has an inner cone (not shown) which tapers to the left in the direction of travel. It is slid in a form-fitting manner onto an outer cone on the transmission main shaft 2 (not shown). In addition, the adapter 6 has an axial or axially parallel drive slot 6c with which the adapter 6 can be connected in a rotationally rigid manner via an inserted wedge 7 with the transmission main shaft 2. One half of said wedge 7 is inserted in a groove of the transmission main shaft 2, the other half in the drive slot 6c of the adapter 6. The clutch hub 4, the adapter 6, and the starter gear 8 are concentrically welded to one another (welded connection is not shown). These components welded to each other are finally fixed to an outer thread 2a on the left end in the direction of travel of the transmission main shaft 2 using a clutch nut 9, wherein said clutch nut 9 engages behind the projection 6b of the adapter 6.

[0034] According to FIG. 2, two brackets 12, 18 are associated with the starter motor. The bottom T-shaped bracket 12 is screwed onto a transmission base plate 97 (see FIG. 6) using a hexagon head bolt 14 and a flat head bolt 16 on the plate-shaped holding element 12a. The top bracket 18 with its bell cap 18a, which is optionally visible from the outside, is screwed onto a fastening projection 12b in the center and to the bottom bracket 12 using two hex head bolts 14 and a perforated plate 20 in between. Two integral, complementary or congruent fastening flanges 12c and 18b which extend from the top cover 18 downwards or from the bottom cover 12 upwards, respectively, are for example used for the screwed connection. The starter shaft 22 of the starter motor, on which the starter shaft pinion 24 is seated, is inserted in this bell cap 18a and slidably supported in a friction bearing 26, for example designed as a bronze bushing. The actual starter motor and its casing 33 are screwed to the top bracket 18 using two hexagon socket screws 30. The shaft 22 is connected via an internal transmission together with an intermediate shaft 28 to the rotor in the electric motor 32. The magnetic switch 34 which supplies the electric motor 32 with the magnetic field is located above the electric motor 32 in the casing 33 of the starter motor. A start button 38 is either located directly in the magnetic switch 34 or on the handlebar of the motorcycle. The electrical connection of the starter motor 33 is implemented with an additional cable stop 36 and a cable guide 42, which is fastened to the casing 33 by means of a perforated plate 40 having a passage 40a that is congruent with the cable guide 42.

[0035] In a preferred embodiment according to FIG. 3, the new battery bracket 70 according to the invention supports the battery 74 in the center of the horseshoe-shaped oil tank 95 (see FIGS. 5 and 6). The battery 74 and its insulation 72 are fastened with two bolts 76 and a clamping bracket 75 to a battery support plate 71. The design of the battery support plate 71 with two curved right angles 71a and the resulting overall orientation of the battery bracket 70 prevent a collision with the top holding part 18 and/or the starter motor casing 33. A sheet metal bracket 78 is screwed to the battery support plate 71 and welded to the welding points 78a on the oil tank. This allows direct fixation between the battery bracket 70 and the oil tank 95. The battery support plate 71 can be fixedly screwed to the rigid frame 85 of the motorcycle and the rear fender. (see FIG. 5):

[0036] According to FIG. 4, a primary chain tensioner 50 as designed for the motorcycles of construction years 1955 to 1957 is provided. A fixing part 52, e.g. made of sheet metal with a circular cutout 52a concentrical to the crankshaft 83 on the crankshaft casing 81 is screwed on for mounting the primary chain tensioner 50 (see FIG. 5, but it shows the embodiment from paragraph [0030]). The fixing part 52 is screwed onto a fastening device 55 via an intermediate piece 54 using two hex head bolts 53, and an anchor plate 56 is seated on said fastening device by means of two flat head bolts 57 and two guides 58 (the lower one of the two screwed connections is not visible). The actual height adjustable chain tensioner 61 is mounted onto said anchor plate 56 using, for example, a hexagonal chain tensioning screw 59 and a chain tensioning nut 60. A chain tensioner plate 62 is attached to this chain tensioner 60 using the chain tensioning screw 59, and the chain tensioning shoe 65 is fastened to said plate using two chain tensioning shoe bolts 63 and a perforated plate 64. The primary chain 84 is slidably supported on said chain tensioning shoe 65 (see FIG. 5). Since the chain tensioning shoe 65 is height adjustable, the primary chain 84 can be retensioned, particularly to counteract wear and tear. This also ensures that a transmission 87 with clutch 89 can always remain at the same position in the rigid frame 85 despite the inevitable lengthening of the chain, and that therefore the starter shaft pinion 24 can always access the starter gear 8 at the same position.

[0037] In another embodiment (shown in FIG. 5 in the installed condition) for the motorcycles built from 1936 to 1954, the primary chain tensioner 50 is fastened by screwing onto the transmission base plate 97.

[0038] FIG. 5 shows the central section of a Harley-Davidson motorcycle that is representative of the motorcycles built from 1936 to 1957. The inner and outer covers of the primary drive system are hidden in FIG. 5 to make the primary drive system visible. The implementation with the engine 80 and the transmission 87 as physically separated assemblies is typical of motorcycles built in these years. The actual engine 80 is connected to the primary drive system in the crankshaft casing 81 via the crankshaft 83. The output pinion 82 which has a different design depending on the construction year period (panhead or knucklehead engine), is seated on the crankshaft 83. To create extra space on the transmission main shaft 2 for the additional starter gear 8, as described in paragraph [0017], the entire clutch 89 is offset by about 8 mm to the left in the direction of travel on the transmission main shaft 2. For the output pinion of the primary chain 84 on the transmission main shaft 2 to be positioned flush in one plane with the output pinion 82 of the engine 80, the output pinion 82 of the engine 80 must comprise a projection or extension of such a thickness that the gear ring of the output pinion 82 is offset by the same distance. The rotating output pinion 82 transmits its kinetic energy via the primary chain 84 onto the transmission main shaft 2 on which the clutch 89 is seated. During the starting process, power transmission is effected from the clutch 89 to the engine 80. The clutch 89 comprises the clutch cage 91 that is visible here and the modified clutch hub 4 hidden behind it in this view (see FIG. 1) and connects the primary drive chain 84 via the transmission 87 with a secondary drive 92. The latter is used for driving the rear wheel, as is known per se. When the outer cover of the primary drive system is installed, the bell cap 18a (see FIG. 2) of the top bracket 18 is the only component of the retrofit kit that is clearly visible, since the primary chain tensioner 50 remains hidden behind the outer cover. One can see that this in particular is a Harley-Davidson motorcycle built in the period from 1936 to 1954 in that the primary chain tensioner 50 shown in FIG. 5 is mounted to the transmission base plate 97 on the rigid frame 85 and not to the crankshaft casing 81. It is apparent that the starter motor 33 or the top bracket 18, respectively, do not collide with the modified battery bracket 70 which fixes the battery 74 in the center of the horseshoe-shaped oil tank 95 because the maximum permissible installation height is complied with.

[0039] FIG. 6 illustrates the layout of the electrical starter system within the rigid frame 85. It is apparent that, due to the design and arrangement of the bottom bracket 12, the top bracket 18, the electric motor 32, and the magnetic switch 34, the available space can be utilized such that the transmission base plate 97, the oil tank 95, and the primary drive system with its primary chain 84 can be kept as original components or equivalent replacement components specific to the respective construction year. This makes it possible to start the engine like before mechanically using the kick starter 99 on the transmission main shaft 2, or electrically by transmitting the rotary motion of the electric motor 32 to the starter gear 8.

[0040] The electrical starter construction kit for a method of retrofitting motorcycles of the Harley-Davidson brand built from 1936 to 1957 with an electrical starter system always includes the following components: a modified and completely welded together clutch (reference symbols 4, 6, 8), an electrical starter motor with a mechanical and electronic installation device (12-42), a modified battery bracket (70-78 without 74). Furthermore, the construction kit includes a specific output pinion 82 depending on the respective assembly and an adapted primary chain tensioner 50. The primary chain tensioner 50 for the construction year period from 1955 to 1957 (reference symbol 50-65) is mounted to the crankshaft casing 81, the one for the construction year period from 1936 to 1954 is mounted to the transmission base plate 97. The method for retrofitting is structured as follows:

[0041] In preparation for the retrofitting method, the existing battery 74 is removed and the engine oil is drained from the oil tank 95. The following parts are removed one after the other: rear wheel, rear fender, oil tank 95, clutch actuator, outer cover of the primary drive gearbox, clutch 89, primary drive and the existing tensioning screw for the primary chain 84. The existing battery bracket removed from the oil tank 95 and destroyed in the process.

[0042] The battery support plate 71 is welded to the oil tank 95. The already welded together modified clutch hub 4 is slid onto the transmission main shaft 2 and used as a template for a cutout along the starter gear 8 on the inner cover of the primary drive gearbox. Then another cutout for the bell cap 18a of the top bracket 18 is made on the inner cover of the primary drive gearbox. Finally, other respective recesses must be made on the inner cover for mounting the primary chain tensioner 50.

[0043] After the transmission 87 has been removed from the transmission base plate 97, the bottom bracket 12 is screwed onto the transmission base plate 97 using the supplied and existing screws (14, 16) and nuts. In motorcycles built from 1936 to 1954, the primary chain tensioner 50 is additionally screwed onto the transmission base plate 97.

[0044] The transmission 87 and the oil tank 95 can be reinstalled after mounting the bottom bracket 12. After reassembly specific to the construction year of the inner primary cover, the modified clutch hub 4 is completed with the remaining components of the clutch 89, e.g. the clutch cage 91. When assembling the clutch hub 4, the wedge 7 is first inserted in the groove provided for it on the transmission main shaft 2. Then the adapter 6 can be slid in a form-fitting manner to the outer cone of the transmission main shaft 2 and the wedge 7. Then the clutch nut 9 can be used to tighten the modified clutch hub 4 on the male thread 2a of the main shaft to a torque of more than 100 Newton meters. The supplied output pinion 82 is installed and put into operation together with the clutch 89 using methods of established practice.

[0045] Then the top bracket 18 of the starter motor 33 can be screwed onto the bottom bracket 12. If required, a cutout can be made on the rear fender using a template. Finally, the electrical cables are installed and the motorcycle can be completely returned to operation in accordance with established practice.

LIST OF REFERENCE SYMBOLS

[0046] 2 Transmission main shaft [0047] 2a Thread on the transmission main shaft [0048] 4 Modified clutch hub [0049] 4a Inner diameter of the modified clutch hub [0050] 6 Gearwheel adapter [0051] 6a Annular disc of the gearwheel adapter [0052] 6b Projection of the gearwheel adapter [0053] 6c Driving element of the gearwheel adapter [0054] 7 Wedge [0055] 8 Starter gear [0056] 9 Clutch nut [0057] 12 Bottom bracket [0058] 12a Plate-like holding element of the bottom bracket [0059] 12b Fastening projection of the bottom bracket [0060] 12c Fastening flange of the bottom bracket [0061] 14 Hexagon head bolt [0062] 16 Flat head bolt [0063] 18 Top bracket [0064] 18a Bell cap of the top bracket [0065] 18b Fastening flange of the top bracket [0066] 20 Perforated plate [0067] 22 Starter shaft [0068] 24 Starter shaft pinion [0069] 26 Bronze bushing [0070] 28 Intermediate shaft [0071] 30 Hexagon socket screw [0072] 32 Electric motor [0073] 33 Starter motor (casing) [0074] 34 Magnetic switch [0075] 36 Cable stop [0076] 38 Start button [0077] 40 Perforated plate [0078] 40a Passage through the perforated plate [0079] 42 Cable guide [0080] 50 Primary chain tensioner [0081] 52 Fixing part [0082] 52a Circular cutout of the fixing part [0083] 53 Hexagon head bolts [0084] 54 Intermediate piece [0085] 55 Fastening device [0086] 56 Anchor plate [0087] 57 Flat head bolts [0088] 58 Guide [0089] 59 Chain tensioning screw [0090] 60 Chain tensioning nut [0091] 61 Height-adjustable chain tensioner [0092] 62 Chain tensioning plate [0093] 63 Chain tensioning shoe screws [0094] 64 Perforated plate [0095] 65 Chain tensioning shoe [0096] 70 Battery bracket [0097] 71 Battery support plate [0098] 71a Curved right angles in the battery support plate [0099] 72 Insulation [0100] 74 Battery [0101] 75 Clamping bracket [0102] 76 Bolt [0103] 78 Sheet metal bracket [0104] 78a Welding section of the sheet metal bracket for fastening to the oil tank [0105] 80 Engine [0106] 81 Crankshaft/engine casing [0107] 82 Engine output pinion [0108] 83 Crankshaft [0109] 84 Primary chain [0110] 85 Rigid frame [0111] 87 Transmission [0112] 89 Clutch [0113] 91 Clutch cage [0114] 92 Secondary drive [0115] 95 Horseshoe-shaped oil tank [0116] 97 Transmission base plate [0117] 99 Kick starter