EP1611346B1 - Attachable rod ignition coil - Google Patents

Description

The invention relates to an attachable pencil ignition coil for a motor vehicle with an ignition coil part comprising a spark plug receptacle, which is designed for fastening the pencil ignition coil to an SAE head of a spark plug.

Likewise, the invention relates to an attachable pencil ignition coil having an ignition coil part and an adapter with a spark plug receptacle, which is designed for attachment of the pencil ignition coil to an SAE head of a spark plug.

It is known to screw rod ignition coils after plugging on the spark plug directly to the engine block to prevent loosening of the connector. Recently, however, plugged-on pencil ignition coils are used instead of the screwed pencil ignition coils, which allow a simpler and thus more cost-effective installation.

Furthermore, pencil ignition coils are common, in which the attachment to the spark plug via an intermediate adapter. The adapter is manufactured separately from the pencil ignition coil and then, if necessary, also during assembly, connected to the pencil ignition coil. These adapters are manufactured for different spark plugs or different plug shaft lengths in different sizes, so that the same ignition coil part can be used for all versions. Since these directly plugged and rigidly locked ignition coils screwing on the engine is unnecessary, resulting in savings in assembly and maintenance.

However, it has been found in practice that in exceptional cases unintentional damage to the pencil ignition coil can occur. z. B. when the pencil ignition coil is plugged in the manual assembly with excessive force. In such an overuse hairline cracks can occur on or in the pencil ignition coil, so that it can lead to malfunction.

DE 199 31 979 A1 relates to a spark plug connector for transmitting the ignition current to a spark plug of an internal combustion engine. In this case, an additional contact element is provided, which is biased by means of a spring element with respect to a front-side connecting piece of the spark plug. However, this is about a spark plug connector, which is the tail of a high voltage cable for connection to a coil assembly.

US Pat. No. 6,491,531 B1 relates to a connector between an ignition coil and a spark plug. The connector should be merged with the ignition coil to a pre-assembly. This pre-assembly is placed in a continued set-up, so that ultimately the pre-assembly is placed on the ignition coil.

US 2001/0045800 A1 relates to a high voltage connector assembly of an ignition device for an internal combustion engine. It is a high voltage cable, wherein a spring element for generating a predetermined pressure, which is to provide a secure electrical connection, is present.

US 4,090,125 discloses an ignition system in which a sensor or detector is to be integrated in a shielded arrangement on the transformer.

US 5,535,736 relates to an arrangement consisting of a coil and a spark plug. This is to be installed as a one-piece unit, but still allow easy access to the spark plug. In doing so, sealants should not be damaged. There are provided elastomeric portions for sealing and friction mounting of the spark plug.

US 5,685,282 relates to an ignition device for an internal combustion engine. In this case, a spark plug is connected via an adapter arrangement with an ignition coil. Vibrations that lead to poor electrical connections should be avoided by providing spring elements for improved electrical contact.

US 6,192,873 B1 discloses a pluggable ignition coil which is to be connected via a spring with a spark plug, not shown or described in detail. In this case, a Frontalkontaktierung is provided, wherein a spring is the better electrical contact.

US 4,831,995 relates to an integrated ignition-transformation assembly for the cylinder of a controlled ignition heat engine. In this case, a spring is provided for better production of the electrical contact.

FR 2624559 A3 relates to an ignition coil, especially for racing engines. Again, a resilient device is provided to ensure proper electrical contact between a sliding part and the spark plug.

The invention is based on the problem to provide a pencil ignition coil that can be easily and safely mounted without the risk of damage.

To solve this problem, it is provided according to the invention in an attachable pencil ignition coil of the type mentioned above, that in the area of the spark plug receptacle of the ignition coil part a shock absorbing element which is formed when plugging the spark plug on the SAE head is arranged, which is disc-shaped.

Likewise, the problem is solved in a pencil ignition coil with an adapter in that between the ignition coil and the adapter and / or the adapter and the spark plug recording a plugging the spark plug arranged on the SAE head shocks damping element is arranged, which is disc-shaped.

The shock absorbing element absorbs the force peaks, which have previously led to damage or destruction of the ignition coil. In this way, the pencil ignition coil is mechanically relieved and the impact energy or at least a substantial portion of the impact energy is absorbed by the shock absorbing element. By the recorded deformation work, a part of the kinetic energy is consumed when attaching the pencil ignition coil. In addition, a counterforce is generated, which is noticed by the person who mounted the ignition coil, so that it reduces their effort. Thus, in the attachable pencil ignition coil according to the invention an accidental violent plugging is prevented, whereby damage can be avoided.

It is particularly advantageous if the shock-absorbing element is deformable upon insertion of the pencil ignition coil on the spark plug with energy consumption.

Even greater protection against failures is achieved when the adapter and ignition coil member are axially movable along a damping path relative to each other. This development of the invention has the advantage that energy can be absorbed along the entire damping path. The shock-absorbing element can be designed so that the attachment force increases continuously. This results in a gradual transmission of power from the ignition coil on the adapter so that sudden acting force peaks that could lead to damage to the components can be avoided.

In the case of the pencil ignition coil according to the invention, provision can be made for a socket to be formed on the adapter or on the ignition coil part, into which socket portion of the respective other part designed in the same manner can be inserted. Preferably, the socket is formed on the adapter. In this socket, the plug-in section used the ignition coil. By using different adapters, it is possible to use the same ignition coil part for different spark plug variants or different plug shaft lengths, which in turn leads to cost savings.

In an alternative embodiment of the pencil ignition coil according to the invention it can be provided that the shock-absorbing element or possibly a second shock-absorbing element is arranged in the region of the spark plug receptacle. The shock absorbing member may be disposed either between the ignition coil part and the adapter or in the region of the spark plug receptacle of the adapter. It is also possible to combine both variants, so that the adapter has a total of two shock absorbing elements. If the shock absorbing element is arranged in the region of the spark plug receptacle, it can be comparatively easily inserted or pressed into the bottom area of the spark plug receptacle. At this point, a circumferential groove may be provided in which the shock absorbing element can be kept.

The adapter can be advantageously made of metal or a metal alloy, in particular of a brass alloy, which has a good electrical conductivity. It can also be provided to combine different metals, for. As a hard metal with a soft.

It is advisable to arrange the shock-absorbing element axially aligned. In this arrangement, it can optimally exert its damping function, since it lies in an axis with the acting Aufsteckkraft.

The shock absorbing element is preferably made of a rubber or silicone material. In principle, however, other materials such as plastic, metal, ceramic or sintered material, with which the required damping effect can be achieved. Different materials can also be combined, conceivable z. B. a shock absorbing element made of rubber that is provided on one or both sides with a metal layer.

Particularly preferred is a shock-absorbing element which is electrically conductive, so that it can transmit the ignition current. In this way, the generation of unwanted sparks between the spark plug head and the plugged-on component (adapter or ignition coil part) can be effectively prevented.

A particularly good damping effect is achieved because the shock-absorbing element is disc-shaped. Such shaped elements are flush with the adapter or the ignition coil, so that a good power transmission is ensured. In addition, they have the advantage that they are easy and inexpensive to produce.

Fig. 1

ein erstes Ausführungsbeispiel der erfindungsgemäßen Stabzündspule, bei dem das Stöße dämpfende Element im Bereich der Zündkerzenaufnahme angeordnet ist;

Fig. 2

ein zweites Ausführungsbeispiel der erfindungsgemäßen Stabzündspule, bei dem das Stöße dämpfende Element zwischen dem Zündspulenteil und dem Adapter angeordnet ist;

Fig. 3

ein drittes Ausführungsbeispiel der erfindungsgemäßen Stabzündspule, bei dem das Stöße dämpfende Element in der Zündkerzenaufnahme angeordnet ist; und

Fig. 4

ein viertes, nicht zur Erfindung gehöriges Ausführungsbeispiel der Stabzündspule, bei dem das Stöße dämpfende Element als Druckfeder ausgebildet ist.

Further advantages and details of the invention will become apparent from the embodiments described below and with reference to the drawings. Showing:

Fig. 1

a first embodiment of the pencil ignition coil according to the invention, in which the shock-absorbing element is arranged in the region of the spark plug receptacle;

Fig. 2

a second embodiment of the pencil ignition coil according to the invention, wherein the shock absorbing member between the ignition coil and the adapter is arranged;

Fig. 3

a third embodiment of the pencil ignition coil according to the invention, in which the shock-absorbing element is arranged in the spark plug receptacle; and

Fig. 4

a fourth, not belonging to the invention embodiment of the pencil ignition coil, in which the shock absorbing element is designed as a compression spring.

In the Fig. 1 to 4 identical components are provided with the same reference numerals.

Fig. 1 shows a first embodiment of the invention, in which the shock-absorbing element is arranged in the region of the spark plug, in a partially sectioned side view.

The pencil ignition coil 1 consists essentially of a Zündspulenteil 24 which is connected to an electronic circuit, not shown, for generating the ignition signal and a housing 5, which protects the inner components and electrically isolated. The Stabzündspule 1 is connected via cable connections, not shown, to other motor units. At the lower end of the ignition coil part 24 is a spark plug receptacle 25, which is plugged onto a spark plug 3.

The ignition coil part 24 and the housing 5 of the pencil ignition coil 1 are fixedly connected to each other, so that impact forces that occur when attaching the pencil ignition coil 1 to the spark plug 3 are transmitted undamped.

At the free end of the ignition coil part 24 there is a spring 13, which in the installed state rests positively against the SAE head of the spark plug 3 and prevents the unintentional release of the ignition coil part 24 from the spark plug 3.

The ignition coil part 24 has in the region of the spark plug receptacle 25 on a circumferential groove 16, in which a disc-like shock-absorbing element 17 is inserted, which is held in the groove 16 positively. The shock absorbing member 17 is made of a rubber material which is electrically conductive.

When the rod ignition coil 1 is fitted with its ignition coil part 24 on the spark plug 3, the force is transmitted from the SAE head of the spark plug 3 via the shock absorbing member 17 to the ignition coil 24. Once the shock absorbing member 17 abuts the head of the spark plug 3, For example, part of the energy used to fit the pencil ignition coil 1 is converted into damping work.

Fig. 2 shows a second embodiment of the invention, in which the shock absorbing member between the ignition coil and the adapter is arranged. As in Fig. 2 can be seen, the pencil ignition coil 1 is attached to the adapter 2 on a spark plug 3. The items are shown in a partially sectioned side view.

The pencil ignition coil 1 consists essentially of an ignition coil part 4, which is connected to an electronic circuit, not shown, for generating the ignition signal and a housing 5, which protects the internal components and electrically isolated. The Stabzündspule 1 is connected via cable connections, not shown, to other motor units.

The pencil ignition coil 1 is connected to the adapter 2 via a male or snap-in connection. In the end region of the ignition coil part 4, a bolt-like plug-in section 6 is formed, which has a circumferential groove 7.

The bolt-like plug-in section 6 is inserted into a receiving opening of the adapter 2. This connector is secured by a securing element 10, which is formed in the illustrated embodiment as a resilient retaining ring. In Fig. 2 is shown to the right of an imaginary center line, that the securing element is held on the outside of the adapter 2 in a groove. Links of an imaginary center line is shown that this groove of the adapter 2 is interrupted in a section, so that the resilient securing element 10 is located at this point within the receiving opening of the adapter 2 and reduces its cross-section. When plugging the adapter 2 with the plug-in portion 6 of the ignition coil 4, the fuse element is first pressed outward until it is in the groove 7 of the plug-in portion after plugging. This prevents inadvertent release of the two parts, at the same time the plug-in portion 6 of the ignition coil 4 and the adapter 2 are vertically displaceable relative to each other. The displaceable distance corresponds the width of the groove 7, the in Fig. 2 is denoted by the letter d. This distance is used when attaching the pencil ignition coil 1 to the spark plug 3 for damping a shock generated during assembly. The distance d is typically 2 mm.

The adapter 2 is formed in its upper region as a socket 11, the diameter of which is adapted to the diameter of the plug-in section 6. The socket 11 has a circular cross-section in the illustrated embodiment. The opposite side of the adapter 2 is designed as a spark plug receptacle 12. In a section along the circumference of the adapter 2 is a spring 13, which rests positively in the installed state of the SAE head of the spark plug 3 and prevents the release of the adapter of the spark plug 3.

Between the end of the plug portion 6 and the bottom of the socket 11, a shock absorbing member 14 is arranged. This element 14 has the shape of a thick disc and abuts on its circumference on the inside of the socket 11. The shock absorbing member 14 is made of a rubber material.

When the pencil ignition coil 1, which is connected to the adapter 2, is plugged onto the spark plug 3, the power is transmitted from the ignition coil 4 via the fuse element 10 to the adapter 2. Since the ignition coil 4 and the adapter 2 are not rigidly connected, takes place First, a virtually force-free relative displacement, the of the in Fig. 2 shown position and in the course of which the drawn attenuation path d decreases, since the plug-in section 6 is moved further into the adapter 2 into it. Since the end face 15 of the plug-in section 6 rests on the surface of the shock-absorbing element 14, the plug-in section 6 can only be pushed further into the socket 11 of the adapter 2 when the shock-absorbing element 14 is simultaneously compressed. In this way, a part of the energy that is expended for attaching the pencil ignition coil 1 is converted into damping work. In particular, high force peaks, usually at the impact of two Body occur, avoided. At the same time, an increasing counterforce is generated, which the person who mounts the pencil ignition coil 1 feels. This increase in force is interpreted by the person as a signal that the pencil ignition coil is correctly attached.

The ignition coil part 4 can be pushed further into the socket until the securing element 10 abuts against the upper edge of the groove 7. In this way, the power transmission from the ignition coil 4 via the fuse element to the adapter 2 take place.

Fig. 3 shows a third embodiment of the invention, in which the shock-absorbing element is arranged in the spark plug receptacle. The adapter 2 has, in the region of the spark plug receptacle 12, a peripheral groove 16 into which a disk-like shock-absorbing element 17 is inserted. The element 17 is held in the groove 16 positively. Since the shock absorbing member 17 is substantially thinner than the shock absorbing member 14, and the damping path is reduced accordingly. The position of the shock-absorbing element 17 within the spark plug receptacle 12 is selected so that it rests in the installed state on the end face of the SAE head 18 of the spark plug 3. Alternatively, it is also possible to provide the shock absorbing member 17 separately from the adapter 2, so that the customer or the mechanic who attaches the pencil ignition coil must first secure the shock absorbing member 17 in the plug receptacle 12 of the adapter 2. However, it is preferred to provide the adapter 2 on the manufacturer side with the shock-absorbing element 17.

When mounting the pencil ignition coil 1, the power is transmitted from the ignition coil 4 via the fuse element 10 to the adapter 2. When the shock absorbing member 17 within the spark plug receptacle 12 comes into contact with the head 18 of the spark plug, the shock is damped, so that no strong impact on the sensitive components of the pencil ignition coil 1 is transmitted.

Fig. 4 shows a fourth, not belonging to the invention embodiment in which the shock absorbing element is designed as a compression spring. The . Ignition coil part 19 has a central recess 20 which is opposite to a recess 21 of the adapter 22 in the installed state. The ignition coil part 19 is connected via the securing element 10 with the adapter 22. In the free space formed from the recesses 20 and 21, a compression spring 23 is used, which exerts a compressive force on the end faces of the recesses 20 and 21. Since the compression spring 23 is installed with a certain biasing force, it is ensured that the ignition coil part 19 is electrically connected to the adapter 22 at any time via the compression spring 23. During operation, the ignition current flows through the compression spring 23. If a shock or a force peak occurs during assembly, this event can be absorbed by the compression of the compression spring 23, which absorbs part of the impact energy. Due to the recycling of material, a part of the energy is destroyed, the remaining part of the energy is then converted by the extension of the compression spring 23 back into shifting work.

Claims (10)

1. Mountable rod ignition coil having an ignition coil part, comprising a spark plug receptacle for attaching the rod ignition coil to an SAE head of a spark plug, wherein a discoid shock absorbing element (17) is arranged in the region of the spark plug receptacle (25) of the ignition coil part (24) for absorbing shocks which occur when the spark plug receptacle (25) is mounted onto the SAE head.
2. Mountable rod ignition coil having an ignition coil part and an adapter which has a spark plug receptacle for attaching the rod ignition coil to an SAE head of a spark plug, wherein a discoid shock absorbing element (14, 17, 23) is arranged between the ignition coil part (4) and the adapter (2) and/or the adapter (2) and the spark plug receptacle (12) for absorbing shocks which occur when the spark plug receptacle (12) is mounted onto the SAE head
3. Rod ignition coil according to claim 2,
   characterised in that
   the adapter (2) and the ignition coil part (4) are movable relative to each other along a damping path in the axial direction.
4. Rod ignition coil according to either claim 2 or claim 3,
   characterised in that
   a socket (11) is formed on the adapter (2) or on the ignition coil part (4), into which socket a correspondingly formed, diametrically opposed plugging portion (6) of the respective other part can be inserted.
5. Rod ignition coil according to any of claims 2 to 4,
   characterised in that
   the shock absorbing element (17) or optionally a second shock absorbing element is arranged in the region of the spark plug receptacle (12).
6. Rod ignition coil according to any of claims 2 to 5,
   characterised in that
   the adapter (2) can be produced from metal or a metal alloy, in particular a brass alloy.
7. Rod ignition coil according to any of the preceding claims,
   characterised in that
   the shock absorbing element (14, 17, 23) can be deformed by energy dissipation when the rod ignition coil (1) is mounted onto the spark plug (3).
8. Rod ignition coil according to any of the preceding claims,
   characterised in that
   the shock absorbing element (14, 17, 23) is arranged in axial alignment.
9. Rod ignition coil according to any of the preceding claims,
   characterised in that
   the shock absorbing element (14, 17) consists of one material from among plastics material, rubber, silicone, metal, ceramic, sintered material, or of a combination of these materials.
10. Rod ignition coil according to any of the preceding claims,
    characterised in that
    the shock absorbing element (14, 17) is electrically conductive.

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