Air filter mounting structure in air conditioning device

Abstract: In an air conditioning device (A) having an air passage device (1) that extends inside an instrument panel (P) in a lateral direction of the body of a motor vehicle, the air passage device (1) has a substantially L-shaped slit (17) for attachment and detachment of an air filter (9), the slit (17) being formed from a first slit (17₁) opening downwardly and a second slit (17₂) opening rearwardly of the vehicle body and a gap (18) is provided between the second slit (17₂) and a front end portion of a glove box (G). This permits a rectangular or square air filter (9) to be attached to and detached from the slit (17) without interfering with the glove box (G), while being rotated slightly along the floor and toe board of the compartment.

Description: The field of the present invention is air filter attachment and detachment structures in air conditioning devices used for a motor vehicle, wherein the air conditioning device has an air passage means that is disposed inside an instrument panel having a glove box facing a compartment of the motor vehicle, the air passage means being located forwardly of the glove box in a body of the motor vehicle and extending laterally of the vehicle body, and wherein an air filter of a rectangular or square plate shape is attached to and detached from the air passage means through an air filter attachment and detachment slit provided in the air passage means. A known air filter provided in an air passage means of an air conditioning device for a motor vehicle has an element made of electrified fiber material and operates to purify the air being introduced into the compartment, by causing dust in the air to be adsorbed onto the element by means of static electricity. The air passage means of such air conditioning device is, however, disposed generally at a lower portion of an instrument panel that is located forwardly of a front passenger seat in the vehicle body and a glove box is mounted on a side of the air passage means close to the compartment. Therefore, the replacement of the air filter must be conducted from below the instrument panel so as not to interfere with the glove box. The distance between the lower surface of the instrument panel and the floor is, however, small and moreover, a toe board is provided continuously from the floor so as to rise upwardly at a forward inclination relative to the floor, so that it is difficult to attach and detach the air filter from below the instrument panel without any special contrivance. Figs. 9-11 show conventional air filter attachment and detachment structures according to the prior art. According to the prior art, it has been proposed conventionally to construct the air filter into a one 01 that is foldable at a plurality of hinge means 01 1 , as shown in Figs. 9 and 10. This air filter 01 has been attached to and detached from an air filter attachment and detachment slit 06 1 formed at a lower surface of air passage means 06 inside an instrument panel 05 while being passed through a space defined among a glove box 02, a floor 03 and a toe board 04. In another known system, as shown in Fig 11, an air filter 01 having notches 01 2 , 01 3 , 01 4 formed at its outer periphery is used, and this air filter 01 has been attached to and detached from at an air filter attachment and detachment slit 06 1 provided at a lower surface of air passage means 06 while being rotated. In case of the first mentioned conventional measure, however, the provision of a plurality of hinge means 01 1 not only makes the structure complicated and raises the production cost but also reduces the effective area of the said element of the air filter 01, leading to an increase in resistance against the air passage and a reduction in the dust trapping and collecting effect. In the latter measure, the provision of the notches 01 2 , 01 3 , 01 4 reduces the effective area of the element of the air filter 01 thereby to increase the resistance against the air passage and lower the trapping effect but also reduces the yield for the element of the air filter 01 at the time of manufacturing. Moreover, in both the measures, it is difficult to visually recognize the air filter attachment and detachment slit 06 1 of the air passage means 06 from the side of the compartment so that there is a problem in the efficiency in performing the attaching and detaching operation of the air filter 01. The present invention has been proposed in view of these circumstances and an object thereof is to facilitate the operation of attaching and detaching an air filter of a rectangular or square plate shape to and from a slit formed at an air passage means of an air conditioning device. According to the invention there is provided an air filter attachment and detachment structure in an air conditioning device for a motor vehicle, wherein said air conditioning device has an air passage means that is disposed inside an instrument panel having a glove box facing a compartment of the motor vehicle, said air passage means being located forwardly of said glove box in the body of said motor vehicle and extending laterally of the vehicle body, and wherein an air filter of a rectangular or square plate shape is attachable to and detachable from said air passage means through an air filter attachment and detachment slit provided in said air passage means, said air filter attachment and detachment slit being formed into a substantially L-shape having a first slit opening downwardly and a second slit opening rearwardly of said vehicle body, said first and second slits being connected to each other, a predetermined gap being provided between said second slit and a front end portion of said glove box. With the above arrangement, even when the air filter is simply formed as a rectangular or square plate shape for the purpose of reducing the production cost and enhancing the dust trapping effect, the air filter can still easily be attached and detached without interfering with the glove box. Furthermore, since the second slit which opens rearwardly of the vehicle body can be recognized visually from the compartment side, the replacement of the air filter with a new one can be done easily while visually confirming the position of the air filter attachment and detachment slit. Preferred embodiments of the invention will now be described by way of example only and with reference to the accompanying drawings, in which: Fig. 1 is a perspective view showing the state of an air conditioning device mounted at an instrument panel, according to a first embodiment of the invention; Fig. 2 is a view showing a diagrammatic structure of the air conditioning device; Fig. 3 is a perspective view of an essential portion of the air conditioning device; Fig. 4 is an explanatory view of the operation of the first embodiment; Fig. 5 is an explanatory view of the operation of a modified form of the first embodiment; Fig. 6 is a view corresponding to Fig. 3 but showing a second embodiment; Fig. 7 is a view corresponding to Fig. 3 but showing a third embodiment; Fig. 8 is a view corresponding to Fig. 3 but showing a fourth embodiment; Fig. 9 is a view corresponding to Fig. 4 but showing a conventional air filter attachment and detachment structure; Fig. 10 is a view seen in the direction of arrows 10-10 of Fig. 9; and Fig. 11 is a view corresponding to Fig. 4 but showing another conventional air filter attachment and detachment structure. Figs. 1 to 5 show a first embodiment according to the present invention. As shown in Figs. 1 to 3, an air conditioning device A of a motor vehicle has its essential portion accommodated inside an instrument panel P which is disposed forwardly of a front passenger seat S (a left side seat in this embodiment). A glove box G is provided on a side of the instrument panel P that faces or is opposed to the compartment. The air conditioning device A comprises an air passage means 1 extending laterally from left to right within the instrument panel P, and there are provided at an upstream end or left end of the air passage means 1 an outside air introduction port 3 for introducing air from outside the compartment and an inside air introduction port 4 for introducing air from inside the compartment which are selectively opened by an intake damper 2. A blower 5 is provided at a location downstream of the intake damper 2 and comprises a motor 6 and a fan 7. The blower 5 operates to feed under pressure the air, that has been taken in through the outside air introduction port 3 or the inside air introduction port 4, toward a cooling unit 8 to be described later. The cooling unit 8 comprises an air filter 9 on the upstream side and an evaporator 10 on the downstream side. The air filter 9 has an element 9 2 of electrified fiber material assembled inside a frame member 9 1 of a rectangular shape and the element 9 2 acts, by means of static electricity, to adsorb and eliminate dust in the air flowing in the passage means 1. Refrigerant in a mist condition of a low temperature and a low pressure is supplied to the evaporator 10 through a compressor, capacitor, liquid tank and an expansion valve, which are not shown, to cool the air passing through the air passage means 1. A heater core 11 is provided at a location downstream of the cooling unit 8 and supplied with water for cooling an engine through a water valve 12. The heater core 11 is disposed in the air passage means 1 so as to interrupt or cover a part of the sectional area of the passage and by adjusting the angle of an air mix damper 13 swung within the passage means the ratio of air passing the heater core 11 and air not passing the core 11 can be changed in a desired fashion. At locations in the air passage means 1 downstream of the heater core 11, a DEF discharge port 14, a VENT discharge port 15 and a HEAT discharge port 16 are provided so as to be open to proper portions within the compartment. As apparent from Figs. 3 and 4, on a portion of the air passage means 1 having a rectangular cross section in which the air filter 9 is to be mounted, there are provided a first slit 17 1 opening downwardly and extending longitudinally of the vehicle body, and a second slit 17 2 which opens rearwardly (toward the compartment) and extends vertically. The rear end of the first slit 17 1 and the lower end of the second slit 17 2 are connected to each other and those slits cooperatively define an air filter attachment and detachment slit 17 of an L-shape. When the air filter 9 is mounted to the air filter attachment and detachment slit 17, an L-shaped cover member 9 3 formed on the frame member 9 1 of air filter 9 is fitted to the slit 17 without any gap left therebetween. A predetermined gap 18 is formed between the second slit 17 2 and a front end portion of the glove box G for avoiding interference between the air filter 9 and the glove box G at the time of attaching and detaching the air filter 9 to and from the slit 17. The operation of the above embodiment according to the invention now will be described below. The outside air which has been introduced from the outside air introduction port 3 or the inside air which has been introduced from the inside air introduction port 4 by means of the blower 5 is fed inside the air passage means 1 toward the cooling unit 8 and, after having had dust removed therefrom by flowing through the air filter 9, is further passed through the evaporator 10 for dehumidification and cooling. The air mix damper 13 is swung to a predetermined position between a solid line position and a dotted line position shown in Fig. 2 dependent on a selected air conditioning mode, that is, cooling mode, heating mode, antifogging mode or the like, whereby the air having passed the evaporator 10 only and thereby having been dehumidified and cooled and the air having passed the evaporator 10 and then passed the heater core 11 and heated up are mixed with each other at a predetermined ratio. The mixed air is discharged from a predetermined one of DEF port 14, VENT port 15 and HEAT port 16 into the compartment. The air filter 9 which has been contaminated by the operations of the air conditioning device A is replaced with a new one by utilizing the above-mentioned air filter attachment and detachment slit 17 provided in the air passage means 1. In the process of attaching the air filter 9 to the air filter attachment and detachment slit 17, it is only required that the air filter 9 of a rectangular plate shape be held with its longer side standing vertically and, in this state, inserted into a place between the floor 19 and the glove box G and thereafter, the lower edge of the air filter 9 be rotated or pushed upwardly along the toe board 20. With these steps, the air filter 9 with its cover member 9 3 passes through the first slit 17 1 in a direction from the lower surface of the air passage means 1 and also through the second slit 17 2 and the gap or spacing 18 between the front end portion of glove box G and the rear surface of air passage means 1, whereby finally the air filter 9 is attached inside the air passage means 1 with its longer side laid horizontally. The detachment of the air filter 9 can be conducted in an order reversed to the just mentioned order. In addition, if the gap 18 is enlarged at a lower portion thereof toward the glove box G, as shown in Fig. 5, the air filter 9 can be attached to and detached from the slit 17 very easily by holding the filter 9 in a horizontally laid-down state but with its front side lifted up slightly. As has been described above, since the air filter attachment and detachment slit 17 provided in the air passage means 1 is formed into an L-shape having a first slit 17 1 and a second slit 17 2 and a gap 18 is formed between the second slit 17 2 and the front end portion of glove box G, the air filter 9 can have the simplest, rectangular shape, to reduce the production cost and enhance the dust trapping effect, while assuring an easy handling of the air filter 9 in attaching and detaching operations. Furthermore, the second slit 17 2 of the slit 17 is opened toward the compartment side and thus can be recognized visually so that the efficiency in the replacement work of the air filter 9 can be enhanced by easily confirming the position of the air filter attachment and detachment slit 17 visually. The present invention has been described above in detail by referring to one embodiment. The invention should, however, not be limited thereto but can be modified in various ways in design. Though the air filter 9 is mounted in the cooling unit 8 in the above-described first embodiment, the air filter 9 can instead be attached to any other appropriate portion in the air passage means 1, for example. More specifically, in a second embodiment shown in Fig. 6, an air filter attachment and detachment slit 17 of an identical structure to that of the first embodiment is formed in a heater duct 21 and the air filter 9 is attached to and detached from this slit 17. In a third embodiment shown in Fig. 7, an air filter attachment and detachment slit 17 is formed at an outlet of the blower 5 which is located at a portion upstream of the cooling unit 8. A fourth embodiment of Fig. 8 has an air filter attachment and detachment slit 17 formed in the air passage means 1 at a location directly downstream of the outside air introduction port 3 and inside air introduction port 4. Incidentally, it should be noted that the air filter 9 is not limited to ones of oblong rectangular shape but may be of other shapes, such as a regular square. Furthermore, the invention is naturally applicable to a case wherein the front passenger seat is located on the right side in the motor vehicle.

Claims: An air filter attachment and detachment structure in an air conditioning device (A) for a motor vehicle, wherein said air conditioning device has an air passage means (1) that is disposed inside an instrument panel (P) having a glove box (G) facing a compartment of the motor vehicle, said air passage means (1) being located forwardly of said glove box (G) in the body of said motor vehicle and extending laterally of the vehicle body, and wherein an air filter (9) of a rectangular or square plate shape is attachable to and detachable from said air passage means (1) through an air filter attachment and detachment slit (17) provided in said air passage means (1) characterised in that said air filter attachment and detachment slit (17) is in the form of a substantially L-shape having a first slit opening downwardly (17 1 ) and a second slit opening rearwardly (17 2 ) of said vehicle body, said first and second slits being connected to each other, a predetermined gap (18) being provided between said second slit and a front end portion of said glove box (G). A structure as claimed in claim 1, wherein said air filter (9) has a cover member (9 3 ) of a substantially L-shape which fits in said air filter attachment and detachment slit (17) without a gap left therebetween.

Inventors: ESAKI HIDENORI, WATANABE YOSHIHIRO, ESAKI, HIDENORI, WATANABE, YOSHIHIRO, ESAKI, HIDENORI, C/O K.K. HONDA GIJUTSU KENKYUSHO, WATANABE, YOSHIHIRO, K.K. HONDA GIJUTSU KENKYUSHO
Applicants: HONDA MOTOR CO LTD, HONDA GIKEN KOGYO KABUSHIKI KAISHA
Application year: 1995
Main classification: B60H3
IPC codes: B60H3, B60H1