JPS59117938A - Drive - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a drive device, in particular for a windshield wiper of a motor vehicle, which comprises an electric drive motor and a gearing driven by the motor.

[Technical background of the invention]

The rotation produced by the windshield wiper across the window plane to be cleaned in a given time unit must be within a magnitude of the order of the number of pendulum movements. The upper limit of this magnitude is imposed, on the one hand, by the occupants to ensure that the windshield wipers do not move too quickly and disturb them, and, on the other hand, to ensure that the wiper rubber and windshield bearings do not wear out too rapidly. It is determined. The lower limit is determined so that the driver can still have good visibility in heavy rain and when driving at high speeds.

In order to obtain a suitable rotational speed, the number of revolutions of the motor shaft per unit time must be reduced by means of a gear mechanism so that a pendulum motion number can be obtained.

For this reason, some of the drives known in the art are designed in such a way that the speed reduction is effected by a gear mechanism, in which the gear elements, ie the parts of the gear member in the gear mechanism, are constituted by gear wheels of different dimensions. In another drive, the reduction is performed by a worm gear, which has a worm and a worm wheel connected to a motor. In this way, the speed reduction at 11504 can be achieved with high efficiency. However, drive devices equipped with a worm gear having a driven gear mechanism as another speed reduction means are also known. As far as drives with rotating motor shafts are concerned, the pendulum gearing h° can be provided with a crank and a follower made up of gears or segments with teeth. The various designs depend on the desired speed reduction and the desired dimensions of the passenger equipment.

German Patent Publication No. 0 827 30 863 discloses a rotary driven shaft with two gear elements of different dimensions formed as gear wheels, i.e. the shaft of a reduction gear, which are injection molded together to form a plastic gear member. A drive device is described. Therein, the larger gear meshes with a gear member formed as a worm with a shaft made of metal material, on which shaft there are seven gear elements.
° Injection molded into the shape of Rustic's worm teeth. The low force gear meshes with the output gear of a reduction gearing system having a metal core onto which a toothed section of plastic material is injection molded. Polyoxymethylene is often used as plastic material)1
used as.

The drive system is made of plastic on the gear element. There is an advantage in reducing weight by using more materials, thus also saving energy. Furthermore, it is easier and cheaper to manufacture than a gear member made only of metal. As is well known, the thermal conductivity of plastic materials is much lower than that of metal materials, and the coefficient of thermal expansion is much larger than that of metal materials. Therefore, when the drive motor is restrained from rotating for a long time,
Parts, elements and components made of plastic material are locally heated to a considerable extent, resulting in a temperature increase, and it is not possible to carry away the heat quickly enough. Due to the expansion of the plastic material caused by the temperature increase and due to the continuous stress, at least the tooth section or the tooth section of the worm undergoes a change in shape and therefore the gearing and consequently the entire drive. no longer functions reliably. Furthermore, the mechanical properties of plastic materials are highly time dependent. This is suitable for newer cars with large windshields and rear windows (necessary to operate the windshield's arms, transmitting greater force over a longer period of time). This is why this type of drive device is suitable for this purpose.

The cylindrical structure gear is used as a gear element in a drive device that attempts to transmit a larger motor output.

Laminated structure gears are made of layered plastic, usually made of duroplastic or woven fabric.
Gears made of thermoplastic plastic reinforced with human body. They have higher mechanical strength and heat load carrying capacity than gears made entirely of plastic.

11-layer structures 41'j are available on the market in the form of plates or gears, they have several alternating layers of plastic (A-material) and fabric in their thickness, and are not coated by milling or other means. The desired profile, for example teeth, can only be provided by complicated manufacturing methods.

The production of this laminated shaft + wheel gear is therefore very expensive.

[Purpose of the invention]

It is an object of this invention to have high efficiency over a long period of time despite the use of plastic material for the gear member, which gear member can withstand continuous heat and , or to develop a drive device of the fi type mentioned at the beginning that can withstand mechanical loads. The plastic material used also allows the production of gear elements with low manufacturing tolerances.

[Summary of the invention]

This problem is solved according to the invention by using a thermoplastic Kazenphi 9-part polyamide as the plastic material. A gear element can be made of this plastic material, which meets all the above-mentioned requirements and outperforms metal, even if previously metal had to be used. All gear parts can therefore be made entirely from this plastic material. However, it is also advantageous to use this plastic material only on the gear element, or only on the teeth of the gear element. This is because they are subject to particularly strong distortions since rJ /r > first ta It). The carbon fiber reinforcement of the additive provides mechanical strength and good thermal stability as well as reduced friction and sagging, thus resulting in a good sliding crystallization, and hence this part of the rod. It only causes a little bit of wear and tear on non-brothers.

Since the subsequent shrinkage is small (13), the combination of polyamide and additive can be used for gear parts or gear elements.
It is particularly dimensionally accurate and stable. Other additives, such as Ranu fibers and minerals, cannot be used as readily for the parts of the gear element that are intermeshed and move relative to each other due to their j' friction properties. Thermoplastic carbon fiber sleeves + iji 71"! J amide bamboo can be processed by injection molding.

Their high stability allows the gear members to be of much smaller dimensions, thus increasing the profitability of the proposed invention by 117+i'+t.

For example, thermoplastic carbon fiber reinforced polyamide is available on the market as a granular molding material made by BASF (→Ultramld VO7513).
It is sold under the name. It consists of polyamide 66 with 20% by weight carbon fiber reinforcement. Gear members were made very successfully from this material, however, gear members with smaller 11 carbon fiber reinforcements also met the aforementioned requirements when tested. Heat stabilized against 1 part by weight of YJE Liamide 66 containing 200 parts by weight of carbon fiber reinforcement before processing to ensure that no defects appear in practice despite the low content of carden fibers. It is recommended to incorporate 1 to 3 parts of polyamide 66. Heat-stabilized polyamide 66 is commercially available, for example, as a granular molding material by BASF under the name Shun Ultramid A3W.

The coefficient of friction of one component of suitably thermoplastic carbon fiber reinforced polyamide made according to the present invention is further reduced by adding a lubricating agent of polynato2fluoroethylene,2(Dfiled molydimolybdenum). Possibly then additional lubrication is no longer necessary and the clearance therefore allows the production of a maintenance-free gearing.

As is clear from the above description, the invention can be used in all types of gearing, and it is suitable for driving rotary or pendulous windshield wipers.

As described in the embodiment described in claim 5, the drive device is an electric 1WD having a rotating shaft! l1Jj
It has a motor and a reduction gear configured as a one-stage worm gear. However, it should be pointed out that the present invention is not limited to this 441i gear device #i.

The output wheel of many conventional drives can be brought to a parked position in the windshield via control means that cooperate with the switch contacts of the wiper circuit. The output gear made of the material according to the invention produces electrical conduction,
The electrical conduction is present to a lesser extent due to the inclusion of carpin fibers and is undesirable for windshield wipers that are effectively connected to the driven wheel. In order to avoid this, it is first proposed to connect the driven wheel and the control means in a form-fit, in which a disc made of electrically insulating material is used. Connected to a 7 ohm fit to the driven wheel. Form-closure can be effected therein by suitable pinhole connections.

The driven wheel can then be made of homogeneous material.

Traditionally, control means have been injection molded onto the driven wheel. New aspects include a die for the driven wheel.
) can be the same for many different types and drives and can be combined with different n control means. This enables simple and economical fabrication of different drive gears.

Especially considering smaller drives with low motor power, it is advantageous to manufacture the driven gear and driven shaft as an integral piece of this material.
') It is reasonable even if amides are relatively expensive. This is because only a small amount of material is required, especially if the gear is constructed as a spoke gear. The high mechanical stability allows this type of gear body design even when the gear thickness is small. Gears are usually pressed onto steel shafts, which is significantly cheaper than carbon fiber reinforced polyamide shafts. However, one embodiment of the invention saves presses and
This embodiment is economically reasonable.

Another embodiment h[11 is an extruder consisting of two driven gears of homogeneous material, namely a core made of a gas-insulating material and an edge made of one of the materials according to the invention! I
IIJ1'4! (To produce the east. If the drive motor is generated by the gear device 1' as described
Means for transmitting the torque reduced by j'' are themselves connected to the core part in a known manner.
If the t1 cape means are installed, no unwanted current will be transmitted to the windshield wiper. Since this design requires only a small amount of carbon fiber reinforcement for the toothed edges, the cost of the driven wheel can also be limited.

Preferably, the core and edge are interconnected in a form-fitting manner by teeth. This type of connection can be made more quickly than with one piece of material, for example by locking the two parts by gluing. In order to avoid the flow of current from the control means via the edges to other gear parts, in this case the worm meshing therewith, it is proposed to dimension the control means to be smaller than the core.

In order to prevent the core part and the edge part from coming out of the gear due to mechanical or thermal loads, it is advantageous if the characteristic data of the core part, in particular the coefficient of thermal expansion, are slightly different from those of the edge part. An electrically insulating material with similar property data as heat dissipation oJ'plastic carbon fiber reinforced polyamide must be used.

Of course, the teeth of the worm are also based on this invention.
01 and a worm shaft made of another material.
, when + is added, the characteristic data of the drive device must also closely match. This applies in particular to the coefficient of thermal expansion.

When only a few mold machines or molds are used for production, Zolast® resin material can be processed in the same way as thermoplastic carbon fiber reinforced polyamide and preferably injection molded. It is particularly advantageous to use it as electrically insulating material. For this purpose, the use of thermoplastic glass fiber reinforced polyamides, in particular polyamide 66, is proposed, the content of glass fiber reinforcement being approximately twice the content of reinforcement in carbon fiber reinforced polyamides. This is because it aligns physical data. Additionally, this material has specific lubricating materials that can be used for d'1' lubrication of polyamides. It is thus ensured that the chemical data are also consistent in this regard.

Furthermore, it is proposed to make the entire worm from thermoplastic carbon fiber reinforced polyamide, as the excellent qualities of the material make it suitable for use in the worm shaft even under torsional and bending strains. If desired, the worm shaft can be made of thermoplastic carbon fiber reinforced polyamide with a greater proportion of carbon fiber reinforcement than the worm teeth to withstand the highest mechanical loads.

In other types of gearing, the use of thermoplastic carbon fiber reinforced polyamide can also be considered for other gear components such as cranks and the like. This results in a drive that saves weight compared to metal cranks and the like and therefore consumes less power than conventional drives. The relatively high cost of thermoplastic carbon fiber reinforced polyamides currently limits this type of implementation. This is because there is a risk that the drives will not be available at competitive prices.

[Act of the Invention/1i1) Example] Hereinafter, an embodiment will be described in detail with reference to the attached drawings. However, the present invention is not limited to these examples.

Electric FA with rotor 9, stator 8 and current collector 7
, <A moving motor 1 is inserted into a cylindrical motor container 6. The motor shaft 1 protrudes from the motor container 6, and is a gear member generally indicated by 10. The gear member 10 consists of a worm shaft 11 having a worm (worm teeth) 12, and is housed in a gear container 5 attached to the motor container 6 with a flange.

The worm 12 is shown as a whole by 20 and is separated by gear members 20 and 1.
This gear member 20 is made of Noranutik's worm wheel 22, and is connected to the driven shaft 21 of the gear mechanism.
It is injection molded on top and has radial teeth 22a. IBIA subject? It1. A lever 90 is fixed to the other end of the + shaft 21 so as to prevent twisting movement relative to the shaft, and is part of the twin 4- link mechanism and is a well-known mechanism for windshield wipers (not shown). are connected by twin ball bearings 99. The worm wheel 22 is designed as a gear with spokes 23;
Therein, the spokes 23 are arranged on the side 2 facing the driven shaft 2.
4 and the driven shaft 21 are located alternately on the side 25 where there is no surface [7],
They are interconnected by webs extending over the entire wall thickness H of the worm wheel 22. On its side 25 not facing the driven shaft 2, the worm wheel 22
is connected to the metal stop control disc '11oo, and 3
Hole 2 through which lugs 1θ1 pass through the worm wheel 22
6 and is holding it on the other side 24. The parking control disc 100 is Waino! - operates in conjunction with a movable contact of a switch of the circuit, which movable contact is mounted on the cover 5a of the gear container 5 and is not shown in the figure.
? - contact the stay control disc 100 when the nui, chi is in its off position;

What is important in this invention is that the worm wheel 32 (g(', I
N and the worm wheel 22 in Figure 2)
Polyamide 66 with carbon fiber reinforcement
The whole is made up of. The worm wheel 32 has good thermal conductivity and a low coefficient of thermal expansion (approximately one-fourth that of the s9 IJ oxymethylene used to date). When the motor shaft 1 is restrained for a long time, the teeth 32m of the worm wheel are far from deforming suddenly like the teeth 22a.

The low coefficient of thermal expansion allows the inter-axle spacing of gear members 30 and 10 to be fixed to a smaller tolerance than the inter-axle spacing C of conventional gear members 20 and 10 (FIG. 1). -a I can do it. This results in better bonding and results! Improve power transmission. Furthermore, the worm wheel 32 has a low density and high mechanical stability, therefore the worm wheel 2
The wall thickness H can be made thinner than 2. Moreover, it has good sliding properties, so that its teeth 32a are subject to very low lΔ wear. The worm wheel 32 is pressed onto a driven shaft 41 of steel, as shown in FIG. Since the reinforcements create a low electrical conductivity in the worm wheel 32, a circular insulating disc 120 of polyoxymethylene is disposed between the worm wheel and the hold control disc 100, details of the insulating disc 120. is shown in FIG. 5.As shown in FIG.
20 covers the entire circular area 35 of the worm wheel 32;
As shown in FIG.
The adjacent surfaces of the insulating disc 120 abut and are congruently disposed such that there is no spacing greater than 0.28 between the peripheral edge 122 of the insulating disc 120 and that of the dwell control disc 100. Insulating disc 120 is secured by lugs 101 of parking control disc 100, which extend through holes 36 and into worm wheel 32. Therefore, the parking control disk 100
to the worm wheel 32 and from there to the driven shaft 41 and to the windshield Y.P-, W.? - it is prevented that undesired mains voltages can be transmitted when the switch is activated;

The gear member 40 in FIG. 6 and FIG.
1 disc and without the insulating disc are shown. These two parts are constructed in a manner similar to that shown in FIGS. 3-5. Gear part A 440 is made of 10% by weight carbon fiber reinforcement RS B 71 Hilyamide 66
In one step, the integral part C is molded,
Therefore, the worm wheel 42 and the moving wheel 4) are made of the same material. Hence the gear? -1μ
The shrine 40 is particularly simple (- it can be manufactured without +4y attachment of the wheel and the shaft, and therefore a reduction in price is achieved.The gear i, 1μ material t, l, especially the eaves HA, Therefore, in addition to the advantages of the previously described embodiments, even better efficiency can be obtained (7) and thus even more energy is saved.

It's the gear member 50 shown in Figures 8 and 24-9.
fJk 1! The IΔ sacroaxis, U1, is made of copper phase.

The worm wheel 52 is constructed using two homogeneous materials and includes a core portion 53 of polyamide 66 containing 20% by weight glass fiber reinforcement and a toothed edge portion 52t. It is arranged around the drive shaft 51 in the radial direction and is pressed thereto. The edges 52m are also made of polyamide 66 with 10% carbon fiber reinforcement. In addition to the teeth of the worm wheel that are provided to mesh with the worm, the edge 52a has teeth 52 connected to teeth 53a of the core portion 53 in a 7 ohm fit.
It has b. This is because polyamide 66 containing 20% by weight glass fiber reinforcement is first injection molded into a mold having the profile of a core section 53, which is then placed in another mold having the shape of a worm wheel 52. He was
It is then injection molded surrounded by polyamide 66 containing 10% carbon fiber reinforcement.

Due to the physical properties, in particular the matching coefficients of thermal expansion of the two materials, a reliable bonding of the core part 53 and the edge part 52a to each other is ensured even under high thermal and mechanical conditions. .

A parking control disk is directly fixed to this worm wheel 52 in a known manner. This is because the material used for the core portion 53 is not electrically conductive. The diameter of the stop control disc is often determined on this stop side (t, J, between the i111 disc and the toothed edge 52h, so that the current flows to the toothed edge and from there to the gear member 10). The size is such that only a gap of approximately 2 mm is left to avoid this.

The gear member 10 is a car whose worm 12 is at least heated. Made of fiber-reinforced polyamide.

Due to its excellent four-dimensional properties, it is proposed to manufacture the entire gear member 10 from this type of material.

It is also possible to consider making a motor of thermoplastic carbon fiber reinforced polyamide. However, in this case the current collector 7 cannot be injection molded directly onto the motor shaft 1, as is the case with some conventional plastic motor shafts, as this would result in a short circuit. However, the motor shaft 1 can be manufactured as an integral part with the gear member 10.

Although the present invention has been described above in relation to a specific device, these descriptions are merely illustrative and do not limit the technical scope of the invention as set forth in the claims.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a drive of conventional design with an electric drive motor and a reduction gear; FIG. 3 is a top view of the gear member of the first embodiment according to the invention, and FIG. 4 is a cross section taken along line A-H in FIG. 3.
Figure 5 is a detailed view of a part of Figure 4, Figure 6 is a cross-sectional view along
The figure is a top view of the gear member of the second actual Afi example of this invention,
7 is a sectional view taken along line A-H in FIG. 6, FIG. 8 is a top view of a gear member according to a third embodiment of the present invention, and FIG. 9 is a sectional view taken along line A-H in FIG. FIG.ノ...Motor shaft, 5...Gear container, 6...Motor container, 7...Hayabusa'iR: child, 8...Nutator, 9...
...Rotor, No.0...Gear part 47.7 J...Worm shaft, 12...A-m, 20...Gear member, 2
No... Driven shaft, 22... Worm wheel, 23
...Shawk, 30...Gear)''<1144.3.
9... Worm wheel, 40... Gear member, 42
... Worm wheel, 50 ... Gear part 4K, 52
... Worm wheel, 53 ... Core part, 100.
... Stall control disc, 120... Insulated same root. 1 person for the disturbance (+11 patent attorney Suzue Takehiko Fi)
'g, θ F labor, g Federal Republic of Germany 7129 Bratzkenheim Meimsheim Birhelm Schmidtstrasse 16

Claims (1)

[Claims] (1) It is equipped with a drive motor and a gear device driven by this motor, and this gear device performs rotational motion at different angular velocities around the rotation axis assigned to it. at least one gear element is attached to each rotation, the gear element having at least one gear element in its tooth area;
At least one of the gear elements Ai+ is in mesh with another gear element, and at least one of the teeth in mesh with the other gear element is made of a plastic material; A drive device characterized in that it is made of Phino-f reinforced polyamide. (2) The drive device according to claim 1, characterized in that the noranutic material is polyamide 66 containing 5 to 20% by weight, preferably 10 to 9% by weight, of a carbon fiber reinforcing material. Cq0(3) plasti, material is 20
Polyamide 6 with heavy carbine fiber reinforcement material
1 to 3 parts of heat-stabilized holamide 66 to 1 part of 66
Claim 2, characterized in that it consists of a mixture of
The drive device described in Section 1. (4) The 7' Ranuchik material is a lubricant of the evening moon, preferably containing 1 to 2 parts by weight of molybdenum (Mf) or 5 to 15 parts by weight of polytetrafluoroethylene. A drive device according to claim 2 or 3, characterized in that: (5) an electric drive motor and a rotating shaft (1) of this motor;
The gear member (10) has a worm shaft (11), on which a worm (12) is attached, which is connected to the second gear part. Worm wheels assigned to (32, 42, 52
) is arranged on the drive shaft of the worm wheel, and the worm fg4 (32, 42, 52
) is characterized in that at least its toothed edges (32a, 42a, 52a) are made of thermoplastic carbon fiber reinforced polyamide.
5. The seating device according to any one of paragraphs 1 to 4. (6) The worm wheel (s2, 4-z, s2) is controlled by the control means (100) that cooperates with the switch contact (110) of the windshield w/l- to stay at the position 1^ of the windshield w/l-.
Claim 5 is characterized in that it is configured so that it can be rotated to a position where
'rl drive device. (7) Worm wheel (42) and driven shaft (41)
) and a gear member made of a carpin fiber-reinforced polyamide of the same thermal ii J plasticity, especially 5 to 20%, preferably 1 d%, preferably lO
made of polyamide 66 containing fiber reinforced material, -
The control means (100) is made of a rod piece, and the control means (100) is connected to the worm wheel (4, 9) through the rlL gas insulation disc (12θ).
7. The driving device fg' according to claim 5 or 6, wherein ill<tl is connected by a form fit. (8) The worm wheels (32) are all made of the same thermoplastic carbon fiber reinforced polyamide, especially from 5 to 20
The weight, preferably 10 weight, is made of polyamide 66 containing fiber reinforcing material, and the control means (1
7. Device according to claim 5, characterized in that the worm wheel (32) is connected in a form fit with the worm wheel (32) via a disc (120) made of an insulating material. (9) Device according to claims 7, d and 8, characterized in that the control means (100) extend over a smaller area than the insulating disc (120). The OI worm wheel (52) has a core part (53) arranged radially around the axis (5), the core part being made of an electrically insulating material and arranged around the core part (53). radial toothed edges (62a,b)
The toothed edge is made of a thermoplastic carpin fiber-reinforced polyamide, especially polyamide 66 containing 5 to 20% carbon fiber reinforcing material, preferably 10% by weight 51%. (52)
is connected to a direct control means (100).
? N motion device h0(1υ :fllJ busy(1 means(1
00) is smaller than the core part (53) by 4Hp at l/i. The edges (5,'a,b) of the worm wheel with teeth (52b + 5 J a )
Claim 10: The driving device f, , J7゜Q, ν'rir is interconnected to the frame fit by. , property data of gas insulating, stunning and thermoplastic carpin fiber reinforced polyamides, especially
The lr4 sign is that the number of jJ grains is the maximum and there is only a slight difference! Articles 10 to 12 of Section 111α of the 1st Permissible Claim “1 self-mounted drive device. 14. Drive device according to claim 13, characterized in that the electrically insulating material is a thermoplastic glass fiber-reinforced polyamide, in particular from 10 to 40 mm. parts, preferably 2
Issue containing 0% by weight of glass fiber reinforcement material? 15. The drive device according to claim 14, wherein the drive device is Riamid 66. OQ The wall thickness H) of the worm wheel (32, 42, 52) is reduced compared to the worm wheel (22) made of unreinforced planutic material. Any of the self-mounted drive devices as set forth in Clause 15. (1) The drive device according to any one of claims 5 to 15, characterized in that the worm wheels (32, 42, 5, 9) are formed as gears with spokes. 01 Worm The drive device according to any one of Items 5 to 15 of Patent No. 1, X+, characterized in that the gear member formed by the worm shaft and the worm shaft is entirely made of thermoplastic carden fiber reinforced polyamide. Worm tooth portion (1
19. The drive device according to claim 18, wherein the drive device is thicker than that of item 2).