JP6085580B2 - Method for manufacturing ignition coil for internal combustion engine - Google Patents

Description

  The present invention relates to a method for manufacturing an ignition coil for an internal combustion engine, and more particularly to the structure formation of an ignition coil for an internal combustion engine.

  In recent years, an internal combustion engine used for an automobile or the like employs a direct ignition system in which an ignition coil is provided in each plug hole. A material suitable for this ignition coil structure is selected from the viewpoint of use environment or durability. For example, a thermoplastic resin such as a polyamide resin or a polyester resin is used (Japanese Patent Laid-Open No. 2001-352012). .

  Of these, “PA6, PA66” for the polyamide resin, “PBT” for the polyester resin, “modified PPE”, etc. as other thermoplastic resins are representative examples.

JP 2001-352012 A

  An ignition coil for an internal combustion engine is required to impregnate the periphery of the secondary coil with a thermoplastic resin without gap so that the periphery of the secondary coil that generates a high voltage (several tens of kV) is reliably insulated. However, as long as Patent Document 1 is read, there has not been sufficiently described a device for distributing the thermoplastic resin moderately in a narrow gap such as between the windings of the secondary coil.

  Further, a production method in which a supercritical fluid is dissolved in a thermoplastic resin and the viscosity of the thermoplastic resin is adjusted is also conceivable. However, in such a manufacturing method, unless the pressure of the mold cavity into which the thermoplastic resin is introduced is appropriately adjusted, the supercritical fluid dissolved in the resin is vaporized and voids are generated around the secondary coil.

  In view of the above problems, an object of the present invention is to provide an ignition coil manufacturing method capable of forming a resin-impregnated body around a secondary coil with high quality.

In order to solve the above problems, the present invention provides the following method for manufacturing an ignition coil for an internal combustion engine. That is, a preloading step for applying a preload to the cavity space in which a secondary coil is set in the cavity, and a resin supplying step for introducing a molten material mixed fluid obtained by melting a supercritical fluid into the cavity space after the preloading step; In the method of manufacturing an ignition coil for an internal combustion engine that implements
In the resin supply step, the molten material mixed resin fluid is introduced into the cavity space while continuing pressure control to avoid gasification of the supercritical fluid,
In the preloading step, the preload is controlled by introducing gas,
The gas is introduced into the cavity space through the resin discharge gate by being introduced into the subcavity.

A preloading step for applying a preload to the cavity space in which a secondary coil is set in the cavity; and a resin supplying step for introducing a molten material mixed fluid obtained by melting a supercritical fluid into the cavity space after the preloading step; In the method of manufacturing an ignition coil for an internal combustion engine that implements
  In the resin supply step, the molten material mixed resin fluid is introduced into the cavity space while continuing pressure control to avoid gasification of the supercritical fluid,
  The cavity includes a resin charging gate, a resin discharging gate provided at a position different from the resin charging gate, and a subcavity communicated with the resin discharging gate.
  In the resin supply step, the molten substance mixed resin fluid flows from the resin charging gate to the resin discharge gate, and the molten substance mixed resin fluid is guided to the subcavity.

Moreover, in the said manufacturing method, it is preferable that a negative pressure is given to the inside of the said cavity when the said resin supply process advances.

Preferably , the internal volume of the subcavity is controllable.

Preferably, in the preloading step, the preload is controlled by introducing gas.

Preferably, the preloading step uses a gas having the same composition as the main component of the supercritical fluid.

Preferably, in the preloading step, the gas is carbon dioxide.

Preferably, after the resin supply step, a solid phase step of solidifying the molten material mixed resin fluid is performed while continuing pressure control to avoid gas phase formation of the supercritical fluid.

  According to the method for manufacturing an ignition coil for an internal combustion engine according to the present invention, the insulating structure around the secondary coil employs a physical property adjusting method for dissolving the supercritical fluid in the thermoplastic resin and adjusting the viscosity of the thermoplastic resin. Is done. For this reason, in the step of impregnating the secondary coil with the insulating resin, the viscosity of the thermoplastic resin is adjusted to be low, so that the thermoplastic resin reliably reaches the peripheral gap portion of the secondary coil.

  In addition, according to this manufacturing method, the following merits are given to the resin casting apparatus that realizes this. That is, since the thermoplastic resin produced by the physical property adjustment manufacturing method is formed only in the structural region around the secondary coil, the pressurizing volume for adjusting the cavity pressure is remarkably reduced. For this reason, in the resin casting apparatus of the manufacturing method, the required output of the compressor or the like is suppressed to the minimum as the pressurization volume decreases, and the apparatus is freed from an increase in size and cost.

  Further, according to such a manufacturing method, since the cavity pressure is appropriately controlled, it is possible to introduce the molten material mixed resin fluid into the cavity space while maintaining the pressure control that avoids the vaporization of the supercritical fluid. Become. For this reason, the manufacturing method provides a high-quality product in which voids are eliminated as much as possible for the resin-impregnated body of the secondary coil.

The figure explaining the assembly process of the secondary coil which concerns on embodiment. The figure explaining the resin formation process of the secondary coil which concerns on embodiment. The figure explaining the low voltage | pressure component assembly process which concerns on embodiment. The figure explaining the low voltage | pressure component assembly process which concerns on embodiment. The figure explaining the clothing process which concerns on embodiment. The figure explaining the impregnation process among the manufacturing processes of the ignition coil which concerns on embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an assembly process of a secondary coil according to the present embodiment. In the manufacturing process, first, a secondary bobbin 110 is prepared, and a conductive wire is wound around the secondary bobbin 110 to form a secondary coil 111. A relay terminal 112 is provided at a predetermined location of the secondary bobbin 110. The output terminal of the secondary coil 111 is connected to one end of the relay terminal 112, and the high voltage terminal 113 is electrically connected to the other end. That is, when a steep magnetic field change occurs inside the winding of the secondary coil 111, the secondary coil 111 generates an induced voltage thereby, and this is transferred from the high-voltage terminal 113 to a subsequent conduction part (such as a spark plug). Output.

  After this step, a molten material hybrid resin is formed in the peripheral region of the secondary coil 111 (see FIG. 2). In this resin forming process, a molten material mixed resin fluid obtained by dissolving a supercritical fluid in a liquid phase thermoplastic resin is used, and the solidified insulating structure (molten material mixed resin 114) is melted by the supercritical fluid. In this state, it is solid-phased. That is, in the resin formation step, the viscosity of the thermoplastic resin in the liquid phase is reduced by using a supercritical fluid (process by physical property adjustment manufacturing method). A structure made of the secondary coil 111 and the molten material hybrid resin may be referred to as a high-pressure part structure 120.

  A resin casting apparatus with a supercritical fluid (hereinafter sometimes referred to as a supercritical casting apparatus) is a device that takes charge of the resin forming process (impregnation process and solid phase process), and generates and discharges a supercritical fluid. And a normal injection molding machine. Among them, the mechanism that generates and discharges the supercritical fluid is a tubular part that draws the polymer solution from the injection molding machine, and the temperature at which the molten material reaches the supercritical fluid (the state in which the temperature and pressure reach the critical point). A supercritical fluid generating part that controls the pressure, an injector part that discharges an appropriate amount of this supercritical fluid into the tube of the tubular part, and the like. In addition, a mold gate is connected to the discharge destination of the tubular part, and the cavity communicates with the internal cavity via the gate. Further, the cavity formed in the mold is appropriately subjected to pressure control by a compressor and temperature control by a heater.

  In the supercritical casting apparatus having such a configuration, a polymer (insulating resin) solution is output from an injection molding machine, and a predetermined ratio of supercritical fluid is charged into the resin fluid. At this time, the supercritical fluid is melted into the resin fluid, and a molten material mixed resin fluid is generated. On the other hand, the pressure in the cavity of the mold is controlled by a compressor, and the molten material mixed resin fluid is supplied to the cavity (impregnation step).

  As described above, according to the method for manufacturing the ignition coil 100 for the internal combustion engine according to the present embodiment, the insulating structure around the secondary coil 111 dissolves the supercritical fluid in the thermoplastic resin, and the viscosity of the thermoplastic resin is increased. A method for adjusting physical properties is used. For this reason, in the step of impregnating the secondary coil 111 with the thermoplastic resin (molten material mixed resin fluid), the viscosity of the thermoplastic resin is reduced as expected, so that the thermoplastic resin ( The molten material hybrid resin is surely distributed.

  Thereafter, the supercritical casting apparatus gradually lowers the temperature of the molten material hybrid resin fluid by controlling the temperature of the mold, and finally solidifies the resin fluid to form a molten material hybrid resin. (Solid phase step). In this solid phase forming step, pressure control in the cavity is performed simultaneously with temperature control, and the cooling operation is advanced so that the molten material corresponding to the supercritical fluid does not undergo gas phase transformation.

  Based on Henry's law, when the supercritical fluid is nitrogen, when the ratio Rate1 of nitrogen (mol) to the base polymer (kg) is “Rate1 <0.0425 × P (MPa)”, dissolution in the polymer Nitrogen is said not to undergo gas phase transformation (ie, firing). Further, when the Rate 2 of carbon dioxide (mol) with respect to the base polymer (kg) is “Rate 2 <0.17 × P (MPa)”, it is said that the dissolved carbon dioxide in the polymer does not substantially undergo gas phase transformation. In the present embodiment, the ratio of the molten material is set to about several percent. In particular, when oxygen dioxide is used as a supercritical fluid, the dissolved amount in the resin base material is larger than that of nitrogen, so that the degree of freedom in adjusting the ratio of the molten material is increased. For this reason, when carbon dioxide is used as the supercritical fluid, it is possible to easily adjust the fluidity of the molten material mixed resin fluid in view of the degree of freedom.

  As shown in this example, by cooling while keeping appropriate conditions for the cavity pressure, the supercritical casting apparatus can cause the resin to move from the liquid phase to the solid phase without firing the molten material related to the supercritical fluid. It becomes possible to transform into a state. According to this, since no void is generated around the secondary coil in the process of cooling the molten material mixed resin fluid, the quality of the insulating structure around the secondary coil is maintained.

  The intermediate product for which the solid-phase process has been completed is then put into a low-pressure part assembly process in which low-pressure parts are mounted around the secondary coil (see FIGS. 3 and 4). The low-voltage component according to the present embodiment includes a terminal relay body 131, closed magnetic circuit cores 132 to 133, a central core 134, a primary coil 135, and a connector structure 136 (not shown in FIGS. 3 and 4). It means that.

  The terminal relay body 131 is made of an insulating structure, and is provided with a receiving space for receiving the high-voltage part structure 120 described above. The accommodation space is provided with a communication hole with the outside, and the high voltage terminal 113 of the assembled high voltage section structure 120 can be connected to the external conduction structure through the communication hole. In addition, the insulating structure of the terminal relay body 131 is formed with a flange so as to surround the accommodation space, and low voltage components such as the closed magnetic circuit cores 132 to 133, the connector structure 136, and the igniter 137 are disposed on the flange.

  Further, the high-voltage unit structure 120 is provided with an insertion hole that penetrates the inside of the secondary coil 111, and the central iron core 134 and the primary coil 135 are respectively inserted into the insertion holes. Therefore, the primary coil 135 is disposed as a wound body around the assembled central iron core 134, and the secondary coil 111 is provided as a wound body on the outer periphery thereof. Each of these components is electrically insulated from each other by the insulating structure. Further, among these configurations, closed magnetic circuit iron cores 132 to 133 are disposed at the end of the central iron core 134, and a coil assembly is formed by these overall configurations.

  A connector structure 136 (not shown) and an igniter 137 are disposed beside the coil assembly. Each coil of the coil assembly is appropriately connected to a connector terminal provided in the connector structure 136 or a terminal provided in the igniter 137. The connector terminal is provided with a power supply terminal, a signal terminal, a ground terminal, and the like. Among these, the power supply terminal is conducted to the primary coil 135, and the signal terminal relays the drive signal to the power transistor in the igniter. That is, in the electromagnetic circuit configured as described above, when an ignition signal (pulse) is applied to the signal terminal, a primary current is temporarily generated in the series circuit of the primary coil 135 and the power transistor, and the timing at which the primary current is cut off. Then, a high voltage (several tens of kV) is output from the secondary coil 111. In an internal combustion engine such as an automobile, an ignition signal is continuously given in accordance with the control rotational speed, and the ignition coil is continuously driven in accordance with this.

  The intermediate product for which the low-pressure component assembly process has been completed is then put into a coating process for coating the outer peripheral insulating resin 140 (see FIG. 5). The outer peripheral insulating resin 140 is cast with a mold so as to cover all or part of the low-pressure components described above. As shown in the figure, the outer peripheral insulating resin 140 according to the present embodiment is laminated and coated so as to cover a part of the connector structure 136, and is laminated so that no other low-pressure parts are exposed. For example, in the case of the molten material hybrid resin 114, a part of the molten material hybrid resin 114 is covered with the terminal relay body 131, and the other part is covered with the outer peripheral insulating resin 140. An insulating structure is formed. However, this is only one embodiment. For example, if the induced voltage of the secondary coil can be reliably insulated by the molten material mixed resin 114, a structure in which the resin 114 is exposed from the outer peripheral insulating resin 140 is used. May be given.

  The outer peripheral insulating resin 140 is formed without a supercritical fluid when it is cast. That is, the resin casting apparatus according to the outer peripheral insulating resin 140 does not require a mechanism for mixing the supercritical fluid into the solution of the outer peripheral insulating resin 140. This resin casting apparatus may be an injection molding apparatus or a transfer mold molding apparatus. However, in the transfer mold forming apparatus, the melted insulator can be pressed and injected at a low pressure, so that it will be easy to mold with an appropriate arrangement without destroying the arrangement of the low-pressure components.

  Note that, in the molten substance hybrid resin, the content of the supercritical fluid is set to about several percent, but it is considered that the difference in thermal expansion coefficient with respect to the base polymer not containing this is not large. Therefore, it is preferable in terms of avoiding thermal stress that the base material polymer (main organic composition) is the same in the molten substance hybrid resin and the outer peripheral insulating resin. For example, when a PBT (Polybutylene Terephthalate) molten substance hybrid resin is used, it is preferable that the outer peripheral insulating resin is also PBT (Polybutylene Terephthalate) to form the structure of the ignition coil. Moreover, when using the molten substance hybrid resin of PA (Polyamide), it is good to form the structure of an ignition coil also as outer periphery insulating resin as PA (Polyamide).

  As described above, according to the manufacturing method according to the present embodiment, two types of insulation structure (melted material hybrid resin 114) by the physical property adjustment manufacturing method and insulating structure (peripheral insulating resin 140) without the physical property adjustment manufacturing method are used. The insulating structure is formed as an ignition coil. Therefore, the insulating structure (molten substance hybrid resin 114) by the physical property adjustment manufacturing method is formed in a limited region with respect to the entire ignition coil 100.

  According to such a manufacturing method, the molten substance hybrid resin 114 obtained by the physical property adjustment manufacturing method is formed in a limited structural region, and thus the pressurizing volume in which the cavity pressure is to be adjusted is remarkably reduced. For this reason, in the resin casting apparatus of the manufacturing method, the required output of the compressor or the like is suppressed to the minimum as the pressurization volume decreases, and the apparatus is freed from an increase in size and cost.

  In particular, the high-voltage part structure 120 according to the present embodiment is formed with the molten material hybrid resin 114 limited to the periphery of the secondary coil 111 and the periphery of the relay terminal 112 and the high-voltage terminal 113. Accordingly, the supercritical casting apparatus is limited in the casting volume as much as possible, so that the required output of the compressor can be suppressed, and the pressure-resistant structure of the compressor peripheral piping and valves can be lowered.

  In FIG. 6, the above-described resin forming step is described in more detail. In the figure, carbon dioxide gas is used as the supercritical fluid, and PA (Polyamide / polyamide resin) is used as the base material of the molten material hybrid resin. That is, PA (Polyamide / polyamide resin) is used as a base material polymer, and carbon dioxide gas as a supercritical fluid is melted thereon to generate a molten material mixed resin fluid. The reason why carbon dioxide gas is used as a supercritical fluid in the present embodiment is that the carbon dioxide gas contributes to improvement of fluidity at the interface with the molten material mixed fluid in the cavity.

  As described above, the resin forming process includes the impregnation process in which the periphery of the secondary coil is impregnated with the molten material mixed resin fluid, and the molten material mixed resin fluid is solidified without foaming the molten material by performing pressure control and temperature control. And a solid phase forming step. Among these, the impregnation step according to FIG. 6 is a preload step (see FIG. 6A) in which the secondary coil peripheral pressure is set in advance before the resin is charged, and the molten material hybrid resin is supplied to the secondary coil after the preload step And a resin supplying step (see FIG. 6B).

  In the preloading step, first, a secondary coil is set inside the cavity C1 formed in the mold, and a cavity space is formed as a gap space between the secondary coil and the cavity wall. In this preloading process, before supplying the resin, carbon dioxide is introduced by a compressor to increase the cavity pressure (internal pressure in the cavity space) and appropriately set the secondary coil peripheral pressure (ie, preload). deep. According to this, when the molten material mixed resin fluid is discharged into the cavity via the resin charging gate G (during the resin supply process), the resin fluid is exposed to an environment of sufficient pressure. Sudden foaming at the interface with the resin fluid is suppressed, and the insulation structure around the secondary coil is maintained in high quality. In this step, the carbon dioxide gas Q is pressurized and injected from the facing side of the resin charging gate G in order to form a counter pressure in the cavity.

  Thus, in this embodiment, since the cavity pressure is appropriately controlled, the molten material mixed resin fluid can be introduced into the cavity space while maintaining the pressure control for avoiding the vaporization of the supercritical fluid. It becomes possible. For this reason, the method for manufacturing an ignition coil for an internal combustion engine according to the present embodiment provides a high-quality product in which voids are eliminated as much as possible for the resin-impregnated body of the secondary coil. In this embodiment, when the resin is filled from the counter pressure state to the extent that the resin is filled, a negative pressure is applied to the cavity. According to this, the resin is urged to flow to a portion of the cavity space that is not filled with resin, and as a result, the insulating structure around the secondary coil is maintained in high quality. The timing for applying the negative pressure is appropriately determined according to conditions such as the mold temperature, the resin injection pressure, the cavity space volume, and the cross-sectional area of the cavity space. It is good to specify.

  Further, in the solid phase process performed after the resin supply process, it is preferable to maintain a pressure state that avoids the vaporization of the supercritical fluid, and to cool and solidify the molten material mixed resin fluid. Thereby, in the cooling period, the opportunity for the supercritical fluid to be deposited as voids is lost, so that the resin impregnated body manufactured according to this process becomes a high-quality product without voids.

  Further, in this method, it is preferable to use an apparatus in which the subcavity C2 adjacent to the cavity C1 (main cavity) is used and the cavity C1 and the subcavity C2 are communicated with each other through the resin discharge gate J. According to this, when the molten substance mixed resin fluid is injected into the cavity space only from the resin charging gate G, the resin discharge gate J provided at a position different from this is the flow destination of the molten substance mixed resin fluid. Therefore, in the resin supply process, the molten material mixed resin fluid flows from the resin charging gate G to the resin discharging gate J, and the resin fluid is guided to the subcavity C2 through the resin discharging gate J. .

  In general, depending on the peripheral structure of the secondary coil, the resin flow rate when the molten material mixed resin fluid is introduced may be locally increased, so that the molten material mixed resin fluid causes a local and temporary pressure drop. Sometimes. However, in the present embodiment, since the subcavity C2 is provided at the destination of the molten substance hybrid resin fluid, the bubbled molten substance is collected in the subcavity C2. The resin structure formed by the subcavity C2 is an end material cut off from the high-voltage part structure 120, but does not affect the quality of the insulating structure around the secondary coil. In this way, the high-voltage unit structure 120 is formed with a high-quality insulating structure without a void or the like around the secondary coil (see FIG. 6C).

  Further, since the main cavity C1 is filled with the resin fluid before the subcavity C2, the cavity C1 (that is, the portion corresponding to the resin impregnated body used as a product) is affected by the change in pressure of the gas. Reduced risk. For this reason, in the cavity C, a resin-impregnated body without voids is manufactured.

  In particular, in such a manufacturing method, the carbon dioxide gas Q is preferably introduced into the cavity space via the resin discharge gate J. According to this, the structure of the mold and its peripheral devices is simplified without providing a separate gas supply path. More preferably, if the inside of the sub-cavity and the discharge port of the compressor (the compressor supplying carbon dioxide) are communicated with each other, the carbon dioxide gas can be easily supplied to the cavity space simply by supplying carbon dioxide gas from the compressor. It becomes possible to give to.

  The subcavity C2 is preferably provided with a volume adjustment mechanism so that its internal volume can be changed. According to this, even when the condition of the main cavity C1 changes or when the size of the secondary coil changes, the cavity volume is changed according to this condition change, and the internal volume of the subcavity is always set to a preferable state. can do.

  Further, the above-described subcavity C2 may have a control function for the volume adjusting mechanism. Regarding the pressure control of the cavity space, there is a case where the pressure control response is better when the internal volume of the cavity (the total volume of the cavity C and the subcavity) is controlled than the control by the compressor. If such a volume adjustment mechanism is provided, it is possible to cause a sudden pressure increase, so that an accidental pressure shortage occurring in the cavity is immediately compensated, and the occurrence of defects due to this incidental event can be avoided. .

  The matrix polymer (main organic composition) of the molten material hybrid resin may be replaced with PBT (Polybutylene Terephthalate) or modified PPE (Modified-Polyphenylen Eether). Here, when examining PBT (Polybutylene Terephthalate), it is clear from the chemical composition structure that water absorption is low, and the bond between PBT molecules is strengthened. On the other hand, PA (Polyamide) has high water absorption because it has a hydrophilic group (amide group). That is, when both are compared, PA (Polyamide) has a larger intermolecular distance that constitutes the polymer, and exhibits better fluidity when the solution resin is charged. In particular, this advantage is significant for PA6 and PA66. Furthermore, since PA (Polyamide) is less likely to be hydrolyzed than PBT (Polybutylene Terephthalate), it is understood that it is suitable for use as a structure.

  DESCRIPTION OF SYMBOLS 100 Ignition coil for internal combustion engines, 110 Secondary spool, 111 Secondary coil, 112 Relay terminal, 113 High voltage terminal, 114 Molten material hybrid resin, 120 High pressure part structure, 122-123 Closed magnetic circuit iron core, 124 Center iron core, 125 Primary coil, 126 Connector structure, 140 Perimeter insulation resin.

Claims (8)

A preloading step for applying a preload to the cavity space in which the secondary coil is set in the cavity, and a resin supplying step for introducing a molten material mixed fluid obtained by melting a supercritical fluid into the cavity space after the preloading step are performed. In the method of manufacturing an ignition coil for an internal combustion engine,
In the resin supply step, the molten material mixed resin fluid is introduced into the cavity space while continuing pressure control to avoid gasification of the supercritical fluid,
In the preloading step, the preload is controlled by introducing gas,
The method of manufacturing an ignition coil for an internal combustion engine, wherein the gas is introduced into the cavity space through a resin discharge gate by being introduced into the subcavity. A preloading step for applying a preload to the cavity space in which the secondary coil is set in the cavity, and a resin supplying step for introducing a molten material mixed fluid obtained by melting a supercritical fluid into the cavity space after the preloading step are performed. In the method of manufacturing an ignition coil for an internal combustion engine,
In the resin supply step, the molten material mixed resin fluid is introduced into the cavity space while continuing pressure control to avoid gasification of the supercritical fluid,
The cavity includes a resin charging gate, a resin discharging gate provided at a position different from the resin charging gate, and a subcavity communicated with the resin discharging gate.
In the resin supply step, the molten material mixed resin fluid flows from the resin charging gate toward the resin discharge gate, and the molten material mixed resin fluid is guided to the subcavity. Manufacturing method of ignition coil. 3. The method of manufacturing an ignition coil for an internal combustion engine according to claim 1, wherein a negative pressure is applied to the inside of the cavity when the resin supply process proceeds.   4. The method of manufacturing an ignition coil for an internal combustion engine according to claim 1, wherein an internal volume of the subcavity is controllable. 5.   The method for manufacturing an ignition coil for an internal combustion engine according to any one of claims 1 to 4, wherein the preloading step controls the preloading by introducing gas.   The method for manufacturing an ignition coil for an internal combustion engine according to any one of claims 1 to 5, wherein the preloading step uses a gas having the same composition as a main component of the supercritical fluid. .   The method of manufacturing an ignition coil for an internal combustion engine according to claim 6, wherein the preloading step uses carbon dioxide as the gas.   The solid phase step of solidifying the molten material mixed resin fluid is performed after the resin supply step, while continuing pressure control to avoid gasification of the supercritical fluid. The manufacturing method of the ignition coil for internal combustion engines as described in any one of thru | or 7 thru | or 7.

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