Weather strip and apparatus and process for manufacturing the same

Abstract: A weather strip (S1) including a plurality of weather strip portions having different circumferential length and being integrally formed as a unit. Such a weather strip (S1) is manufactured by molding a starting product of the weather strip and subsequently forming or shaping the starting product. The forming of the starting product is applied on partly or throughout the entire length thereof.

Description: The present invention relates to a weather strip and apparatus and process for manufacturing the same, and more particularly, the invention relates to a irregular shaped weather strip or a weather strip which includes a plurality of portions having different circumferential length or different cross-sectional configurations and apparatus and process for manufacturing the same. The door of an automobile is provided with a weather strip to seal a clearance formed between the door and the body so that entry of raindrops and the like is effectively prevented. The clearance formed between the door and the body is not generally uniform; therefore, the door is conventionally provided with a weather strip which includes a plurality of portions having different circumferential length or different cross-sectional configurations each other, so that such a clearance is sufficiently sealed to prevent entry of raindrops and the like. In some of weather strips provided on automotive doors, the outer circumferential length of a portion positioned on the frame portion of the door is different from that of a portion positioned on the panel portion of the door. Such a weather strip, when the door is closed, acts as a member to encourage the stabilization of the door and to enhance sealing performance between the door and the body. A conventional process for manufacturing the irregular shaped weather strip comprises the steps of molding a plurality of weather strip fractions having different circumferential length each other produced by extruding procedure, fitting the fractions into bonding dies and bonding the fractions at the ends to produce a weather strip. Thus, since the conventional process for manufacturing the irregular shaped weather strip includes a step of bonding the weather strip fractions at the ends, the weather strip as produced has a plurality of joining portions. A problem usually associated with the conventional process is that the produced weather strip exhibits undesirable awkward appearance. Another problem usually associated with the conventional process is that the produced weather strip tends to be broken at the joining portions. A further problem usually associated with the conventional process is that a variety of molding dies and bonding dies are required to produce the weather strip, and these dies have to be replaced whenever the design of the weather strip is changed. This may lead to increased working time. A still further problem usually associated with the conventional process is that the process includes many number of basic steps to produce the weather strip, thereby causing increased working time and labour cost. It is an object of the invention to provide a weather strip which may exhibit a good appearance and has desirable strength. It is another object of the invention to provide a manufacturing process of the weather strip in which the problem associated with the conventional process is eliminated. It is a further object of the invention to provide apparatus for manufacturing the weather strip suitable for practising the process. US-A-4 851 067 discloses an irregularly-shaped weather strip in accordance with the prior art portion of claim 1. This prior weather strip, when viewed in section, has a hollow portion and extending from that hollow portion, a projecting flange, the shape and length of which is varied to change the cross-sectional form of the weather strip by forming a slit through the flange and then rejoining the flange, either with an overlap or with part of the flange removed. This prior weather strip does nothing to overcome the problem of the variable spacing between the door and the door frame and around various parts of the periphery of the door which can most efficiently be sealed by having the hollow portions of the weather strip at different parts of the door of different cross-sectional dimensions. The present invention appreciates how a weather strip can be integrally formed with different parts end-to-end, each part having a hollow cross-section with a different cross-sectional shape, particularly adapted to the gap to be sealed at a particular location around the door periphery. The present invention, as characterised in claim 1, provides a weather strip which has been formed integrally, as by a continuous extrusion, with different portions of the length of the strip being provided with hollow portions of different cross-sections providing a very rugged and reliable weather strip, when mounted in an automotive vehicle. US-A-4 851 067 also provides the basis for the prior art portions of process claims 6 and 9 and for the apparatus claims 10 and 14. The process as claimed in claim 6 can be carried out using the apparatus of claim 10 and relates to manufacture of the weather strip of the invention in which the whole length of the hollow portion of the strip is slit during extrusion, with that slit being widened where the hollow portion is required to have a small dimension, the slit subsequently being joined and seamed together to provide the resulting product of claim 1. Claims 9 and 14 relate to an alternative form of the invention where the part of the weather strip having a hollow portion of greatest dimension is unslit and it is only that portion or those portions of the weather strip which are required to have a smaller cross-sectional dimension for their hollow portion which have material removed therefrom to form a slit which is subsequently joined to provide the finished integral article. With the present invention, the portions of the weather strip are integrally formed as a unit, thereby offering the advantage that the weather strip exhibits a good appearance and has desirable strength and the process includes less basic steps to produce the weather strip, thereby offering the advantage that the working time is decreased. Also, as the apparatus may include no end-to-end bonding die and less moulding dies, the cost of the apparatus is remarkably decreased. The present invention will be further described by way of non-limitative example, with reference to the accompanying drawings, in which:- FIG. 1 is a fragmentary perspective view of an automobile of which a door is provided with a weather strip of the present invention; FIG. 2 is a plan view of the door; FIG. 3 is an elevatlonal view of the weather strip provided on the door; FIG. 4 is a view showing the relation between the door and an opening edge of a body of the automobile; FIG. 5 is a fragmentary perspective view of the weather strip; FIG. 6 is a fragmentary sectional view of apparatus according to a first embodiment of the present invention under the condition that an starting product is being molded; FIG. 7 is a fragmentary sectional view of the apparatus under the condition that a first portion is being formed; FIG. 8 is a fragmentary sectional view of the apparatus under the condition that a second portion is being formed; FIG. 9 is a perspective view of the apparatus; FIG. 10 is a perspective view of the apparatus under the condition that a second portion is being formed; FIG. 11 is a view showing a position of a cutter when the first portion is formed; FIG. 12 is a view showing a position of a cutter when the second portion is formed; FIGS. 13 and 14 are elevatlonal views of a fixed forming roll and a movable forming roll, respectively; FIG. 15 is a fragmentary perspective view of a weather strip which can be produced by the present invention; FIG. 16 is a fragmentary sectional view of apparatus according to a second embodiment of the present invention under the condition that the starting product or the first portion is being molded; FIG. 17 is an elevational view of the apparatus under the condition that the starting product or the first portion is being molded; FIG. 18 is a fragmentary sectional view of the apparatus under the condition that a second portion is being formed; FIG. 19 is an elevational view of the apparatus under the condition that the second portion is being formed; FIG. 20 is a perspective view of FIG. 16; FIG. 21 is a perspective view of FIG. 18; FIG. 22 is a rear elevational view of a movable forming die; FIG. 23 is a front elevational view of a fixed and a movable forming die; FIG. 24 is a sectional view taken along lines X-X of FIG. 23; FIG. 25 is a sectional view of the weather strip into which a cutter is penetrated; FIG. 26 is a sectional view of the weather strip on which a slit is formed; FIG. 27 is a sectional view of the cutter; FIG. 28 is an elevational view of apparatus according to a third embodiment of the present invention under the condition that a first portion of another weather strip is being molded; FIG. 29 is a sectional view of the first portion of the weather strip; FIG. 30 is an elevational view of the apparatus under the condition that a second portion of the weather strip is being formed; FIG. 31 is a sectional view of the second portion of the weather strip; FIG. 32 is an elevational view of the apparatus under the condition that a third portion of the weather strip is being formed; FIG. 33 is a sectional view of the third portion of the weather strip; FIG. 34 is a sectional view of a first portion of still another weather strip which can be produced by the present invention; FIG. 35 is a sectional view of a second portion of the weather strip; FIG. 36 is a view showing the difference between the configurations of the first and second portions of the weather strip; and FIG. 37 is a perspective view of the weather strip. Detailed Description of the Preferred Embodiment Referring now to FIGS. 1 to 5, shown therein is a irregular shaped weather strip S1 according to the present invention which is applicable to a door 1 of an automobile. Further, for convenience in terminology, the irregular shaped weather strip will be called a "weather strip" in the following description. In FIG. 4, phantom lines I', II', III' and IV' correspond to sectional views of a body 2 taken along lines I-I, II-II, III-III and IV-IV in FIG. 2, respectively. As will be observed from FIG. 4, the cross-sectional configuration of an opening edge 2a of the body 2 which faces to a door opening 3 is not generally uniform, that is, the cross-sectional configuration of a portion facing to a frame portion 1a of the door 1 is different from that of a portion facing to a panel portion 1b of the door 1. As shown in FIGS. 1 and 3, the weather strip S1 is annularly provided on an inner surface of the door 1. The weather strip S1 includes a first portion S1a positioned on the door frame portion 1a and a second portion S1b positioned on the door panel portion 1b. The outer circumferential length or outer configuration of the first and second portions S1a, S1b are sized to effectively seal a clearance formed between the door 1 and the opening edge 2a of the body 2 when the door 1 is closed. The first and second portions S1a, S1b are integrally formed as a unit to form a transitional portion S1t therebetween. The outer circumferential length of the first portion S1a is of a size sufficiently greater than that of the second portion S1b so that the amount of deformation of the first portion S1a is greater than that of the second portion S1b when the door 1 is closed. With this construction, when the door 1 is closed, the biasing force against the opening edge 2a of the body 2 due to the deformation of the weather strip S1 is increased in the first portion S1a. The different degree of the biasing force allows for enhancement of the stabilization of the door 1 and the sealing performance between the door 1 and the body 2. The weather strip S1 is an integrally formed member but is bonded at both ends to form a connecting portion 4 when it is provided on the door 1, as shown in FIG. 3. Referring now to FIGS. 6 to 14, shown therein is apparatus for manufacturing the weather strip S1 according to a first embodiment of the invention. The apparatus includes a molding die 5. The front end surface 5a of the molding die 5 is formed with an opening 7 into which a projection P having a width W1 is projected (FIGS. 6 to 9). As will be recognized, the opening 7 is configured substantially to the outer configuration of a starting product S1' (FIGS. 6 to 8) as described hereinafter. As shown in FIG. 9, the molding die 5 is provided with a core member 8 which is axially inserted into the opening 7 so as to contact the lower edge of the projection P, thereby to provide on the molding die 5 with an extruding opening 7a through which a molding material may be extruded (FIG. 9). The core member 8 is partially projected from the front end surface 5a of the molding die 5 over a desired length. The projected portion of the core member 8 is formed with shoulder portions 8a, 8b at one side surface thereof to forwardly diminish the circumferential length thereof. As shown in FIGS. 7, 8 and 10, the apparatus includes a fixed forming roll 9 and a movable forming roll 11 which are positioned adjacent to the shoulder portions 8a, 8b of the core member 8, respectively. The movable forming roll 11 may be reciprocally moved in the direction perpendicular to the axis of the core member 8. As shown in FIGS. 13 and 14, the fixed forming roll 9 and the movable forming roll 11 are configured to the outer configuration of a portion C1a of the first portion S1a and a portion C1b of the second portion S1b, respectively. The front end surface 5a of the molding die 5 is provided with a hydraulic cylinder 12 with a rod 12a. The free end of the rod 12a is fixedly provided with a cutter 13. When the cylinder 12 is actuated, the rod 12a is projected to move the cutter 13 in the direction perpendicular to the axis of the core member 8. As shown in FIG. 9, the core member 8 is provided with an opening 14 through which the cuter 13 is vertically inserted, thereby to permit the reciprocal movement of the cutter 13 without interfering with the core member 8. The weather strip S1 is manufactured by the above-described apparatus. As will be appreciated, if the forming rolls 9, 11 is not included in the apparatus, when a molding material is extruded from the extruding opening 7a of the molding die 5, the starting product S1' is formed, as shown in FIG. 6. The starting product S1' is provided with a slit 6 formed longitudinally thereto and having a width of W1. The slit 6 is formed by projection P. In a typical operation to form the weather strip S1, as shown in FIG. 7, the starting product S1' is advanced to pass between the fixed forming roll 9 and the shoulder portion 8a where a side portion of the starting product S1' is shaped by the roll 9 to form the first portion S1a of the weather strip S1. In this step, the movable forming roll 11 is sufficiently apart from the core member 8 so as not to affect the first portion S1a. Also, the rod 12a of the cylinder 12 is retracted to align the cutter 13 to the projection P so that the cutter 13 remains in the slit 6 on the starting product S1' (FIGS. 7, 9 and 11). When the first portion S1a is formed, the slit 6 on the starting product S1' is disappeared to longitudinarily form an abutting portion on the first portion S1a. The abutting portion is simultaneously bonded to form a seam 15 (FIG. 13). This step is continued until the desired length of first portion S1a is obtained. After the step for forming the first portion S1a is completed, the movable forming roll 11 is moved to a forming position (FIG. 8) so that a second starting product S1' is shaped to form the second portion S1b. As will be easily understood, before the forming roll 11 is moved to a forming position, the rod 12a of the cylinder 12 is projected to move the cutter 13 (FIGS. 8 and 12). When the starting product S1' is advanced, the cutter 13 partly cut off a thin piece 18 from the staring product S1' to form an enlarged slit 6' having a width W2 greater than the width W1 of the slit 6. The thin piece 18 cut off from the starting product S1' is collected and discarded as waste (FIG. 10). As will be appreciated, the width W2 is substantially equal to the deformation distance of the starting product S1' which is given by the both forming rolls 9, 11. As shown in FIG. 8, the starting product S1' is advanced to pass between the fixed forming roll 9 and the shoulder portion 8a where a side portion of the starting product S1' is shaped by the roll 9 where the width W2 of the slit 6' is reduced to form an intermediate slit 6'' having a width of W3. The starting product S1' is subsequently introduced between the movable forming roll 11 and the shoulder portion 8b of the core member 8 where the side portion of the starting product S1' is further shaped by the roll 11 to form the second portion S1b. When the second portion S1b is formed, the intermediate slit 6'' remained on the starting product S1' is disappeared to longitudinarily form an abutting portion on the first portion S1b. The abutting portion is simultaneously bonded to form a seam 15 (FIG. 14). This step is continued until the desired length of second portion S1b is obtained. The apparatus may also include a conditioning roll 16 which is adapted for conditioning the surface of the area to be bonded, and a planing roll 17 which is positioned downstream of the roll 16 and is adapted for planing the surface of the area. These rolls 16, 17 cooperate to produce the seam 15 having excellent regurality and uniformity. The preferred embodiment herein described may be modified as follows, for example. 1) A pair of movable forming rolls 11 may be used to form a weather strip which includes three portions having different circumferential length each other. It is to be understood that in such a case, the core member 8 is provided with three shoulder portions. 2) The cutter 13 may be operated even when the first portion S1a is formed so that the cut off piece 18 is obtained as a continuous piece extending over the entire length of the weather strip S1, thereby to facilitate an operator to handle the cut off piece. 3) The space formed between the rolls 9, 11 and the core member 8 may be smaller than the thickness of the wall of the starting product S1' to enhance the weather strip S1 in quality. 4) As shown in FIG. 15, the weather strip to be formed may be of a configuration as designated by S5. As will be understood, the rolls 9, 11 have to be replaced by the other rolls. Referring now to FIGS. 16 to 27, shown therein is apparatus for manufacturing the weather strip S1 according to a second embodiment of the invention. As shown in FIGS. 16 to 23, the apparatus includes a molding die 50 of which the front surface 50a is provided with a circular base plate 60. The front surface 60a of the base plate 60 is formed with an opening 70 which is configured substantially to the outer configuration of the first portion S1a of the weather strip S1. The front surface 60a of the base plate 60 is provided with a fixed forming die 80 and a movable forming die 90 engageable with the die 80. The front face 60a of the base plate 60 is also provided with a guide member 100 to guide the movable forming die 90 (FIG. 21). The fixed forming die 80 has a notch 80a which is configured to the outer configuration of the first portion S1a excepting the portion C1a at the rear surface of the die 80. Also, the fixed forming die 80 is partly provided with inclined surfaces 80c, 80d so that the notch 80a is configured to the outer configuration of the second portions S1b excepting the portion C1b at the front surface of the die 80 (FIGS. 17, 19, 20 and 23). The movable forming die 90 has a notch 90a comprising of an inclined surface. The notch 90a is configured to the outer configuration of the portion C1a of the first portion S1a at the rear surface of the die 90 and is configured to the outer configuration of the portion C1b of the second portion S1b at the front surface of the die 90 (FIGS. 17, 19, 20 and 22). As will be understood, the fixed and movable forming dies 80, 90 have inclined upper abutting surfaces 80b, 90b, respectively. Therefore, when the fixed and movable forming die 80, 90 are completely engaged each other, an opening 310 is formed therebetween (FIG. 19). The opening 310 is configured to the outer configuration of the first portion S1a at the rear surface of the engaged dies 80, 90 and is configured to the outer configuration of the second portion S1b at the front surface of the engaged dies 80, 90. As shown in FIGS. 16 and 18, the molding die 50 is provided with a core member 120 which is axially inserted into the opening 70, thereby to provide the base plate 60 with an annular extruding opening 70a through which a molding material is extruded to form a starting product S1''. The core member 120 has an outer configuration identical with the inner configuration of the first portion S1a of the weather strip S1 so that the configuration of the extruding opening 70a is identical with the cross sectional configuration of the first portion S1a. The core member 120 passes through between the notches 80a, 90a of the dies 80, 90 and partially projects from the front surface of the dies 80, 90. The core member 120 is provided with a shoulder portion 120a at one side surface thereof to diminish the circumferential length thereof for forming a diminished portion 120b which has an outer configuration identical with an inner configuration of the second portion S1b of the weather strip S1. Also, the shoulder portion 120a is positioned in alignment with the notches 80a, 90a and is inclined so as to substantially be parallel to the wall surface of the notch 90a. Therefore, when the fixed and movable forming dies 80, 90 are completely engaged with each other, the dies 80, 90 cooperate with the core member 120 to form a forming opening 110 therebetween. As will be recognized, the forming opening 110 has a configuration identical with the cross sectional configuration of the first portion S1a at the rear surface of the engaged dies 80, 90 and has a configuration identical with the cross sectional configuration of the second portion S1b at the front surface of the engaged dies 80, 90. As shown in FIGS. 23 and 24, the fixed forming die 80 is provided with a vertical groove 130 which extends from the upper surface of the die 80 into the notch 80a of the die 80. Also, the forming die 80 is formed with an aperture 140 which communicates with the groove 130 and opens in the front surface of the die 80. A cutter 150 is slidably received in the vertical groove 130, having a discharging aperture 150a from which a cut off piece (described hereinafter) is discharged. The weather strip S1 is manufactured by the above described apparatus. As shown in FIGS. 16, 17 and 20, under the condition that the movable molding die 90 is apart from the fixed molding die 80 and that the cutter 150 is upwardly shifted so as not to project into the notch 80a, a molding material is extruded from the extruding opening 70a formed between the opening 70 of the base plate 60 and the core member 120 where the starting product S1'' is continuously formed. As will be easily understood, the cross sectional configuration of the starting product S1'' is identical with that of the first portion S1a of the weather strip S1. Therefore, the starting product S1'' is used as the first portion S1a of the weather strip S1 without applying any forming procedure. Thus, the first portion S1a may be formed only through an extruding operation. This step is continued until the desired length of first portion S1a is obtained. After the desired length of first portion S1a is formed, the movable forming die 90 is moved to be engaged with the fixed forming die 80 so that the starting product S1'' following to the first portion S1a is shaped to form the second portion S1b (FIGS. 18, 19 and 21). As will be easily understood, before the movable forming die 90 is engaged with the fixed forming die 80, the cutter 150 is downwardly shifted so that the end portion of the cutter 150 is projected into the notch 80a (FIGS. 19 and 25). When the starting product S1'' extruded from the extruding opening 70a is advanced, the cutter 150 may partly cut off a thin piece 170 from the starting product S1'' to longitudinary form a slit 160 on the starting product S1'' (FIG. 26). The thin piece 170 cut off from the starting product S1'' is discharged from the aperture 150a and the discharging aperture 140 (FIGS. 21 and 27). As will be appreciated, the width of the slit 160 is substantially identical with the deformation distance of the starting product S1'' which is given by the forming die 90. As shown in FIG. 18, the starting product S1'' formed with the slit 160 is advanced to pass the forming opening 110 formed between the notches 80a, 90a of the forming dies 80, 90 and the core member 120. When the starting product S1'' is passed through the forming opening 110, the side portion of the starting product S1'' is shaped. Thus, the second portion S1b is effectively formed because the forming opening 110 is configured as above. When the second portion S1b is formed, the slit 160 on the starting product S1'' is disappeared to longitudinary form an abutting portion on the formed first portion S1b. The abutting portion is simultaneously bonded to form a seam (not shown). This step is continued until the desired length of second portion S1b is obtained. Some embodiments modified from the second embodiment will now be described with reference to FIGS. 28 to 37, wherein only parts different from those shown in FIGS. 16 to 27 will be explained. FIGS. 28 to 33 shows a third embodiment modified from the second embodiment. Apparatus and process of the third embodiment may produce a weather strip S2 including a first portion S2a (FIG. 29), a second portion S2b (FIG. 31) and a third portion S2c (FIG. 33) which have different outer circumferential length and cross sectional configurations relative to each other. As will be appreciated from FIGS. 29 and 31, in such a weather strip S2, the circumferential length of the second portion S2b is considerably shorter than that of the first portion S2a. As shown in FIGS. 28, 30 and 32, the apparatus includes a fixed forming die 210 and a pair of movable forming dies 220, 230 and also includes a movable cutting die 270. In a typical operation to form the weather strip S2, under the condition that the movable forming dies 220, 230 and the movable cutting die 270 are apart from the fixed forming die 210, a molding material is extruded to form the first portion S2a of the weather strip S2 (FIG. 28). After the desired length of first portion S2a is formed, the movable forming dies 220, 230 are moved to be engaged with the fixed forming die 210 for forming the second portion S2b of the weather strip S2 (FIG. 30). Subsequently, the movable cutting die 270 is moved to a desired position to cut off a part of the weather strip (corresponding to a projecting portion 280 of the second portion S2b), thereby to form the third portion S2c of the weather strip S2 (FIG. 33). FIGS. 34 to 37 shows a fourth embodiment modified from the second embodiment. Apparatus and process of the fourth embodiment may produce a weather strip S3 including a first portion S3a and a second portion S3b. In producing procedure of the weather strip S3, a pair of slits 260 are formed on the extruded member (not shown) following to the second portion S2a before forming the second portion S3b. As will be easily understood, the apparatus includes a pair of cutters (not shown) to form the slits 260. The preferred embodiments herein described are intended to be illustrative of the invention and not to limit the invention to the precise form herein described. They are chosen and described to explain the principles of the invention and their application and practical use to enable others skilled in the art to practice the invention.

Claims: An irregularly-shaped weather strip for attachment to an automobile door (1) to seal a clearance space between the door (1) and a perimeter opening (3) in an automobile body (2), said weather strip (S1) comprising first and second parts (S1a,S1b) integrally formed end-to-end and having different cross-sections, each of said first and second parts respectively comprising a hollow portion, characterised in that the cross-sectional area of the respective hollow portions of the first and second parts (S1a,S1b) are different with the external and internal circumferential lengths of the cross-section of the hollow parts of the first part (S1a) being different from the external and internal circumferential lengths of the cross-section of the hollow portion of the second part (21b). A weather strip as claimed in claim 1, wherein said second cross-sectional area, said second outer circumstantial length and said second inner circumferential length are less than said equivalent dimensional parameters of said hollow portion of the first part (S1a). A weather strip as claimed in claim 1 or 2, wherein the wall thickness of the hollow parts of the first and second parts (S1a,S1b) of said weather strip (S1) is substantially uniform. A weather strip as claimed in claim 1, 2 or 3, wherein more than two of said integrally formed weather strip parts (S1a,S1b) are provided, each with a differing cross-sectional area. A weather strip as claimed in claim 1, 2, 3 or 4, wherein at least the second (S1b) of the parts has a hollow portion, the wall of which comprises a longitudinally extending seam (15). A process of manufacturing an irregularly-shaped weather strip (S1) comprising a first weather strip part (S1a) having a first cross-sectional area and at least one hollow weather strip part (S1b) integrally formed end-to-end with said first weather strip part (S1a) and having a second cross-sectional area, comprising the steps of extruding a moulding material from an extruding opening (7a) formed on a moulding die (5) to produce a starting product (S1') of the weather strip including a hollow portion, said starting product being provided with a slit (6) extending longitudinally thereof with part of the starting product having the width of said slit (6) increased along a length equivalent to the second weather strip part (S1b) prior to the sides of the slit (6) being brought together to form a longitudinal seam (5) with the second longitudinal part (S1b) having a smaller cross-sectional area than the first longitudinal part, characterised in that said longitudinal slit (6) is formed through the wall surrounding the hollow portion of the starting product (S1'), in that the slit starting product is caused to pass a first forming roll (9) to form the first weather strip part (S1a) and simultaneously to close the slit (6) for forming a seam (5) on the first weather strip part (S1a), in that following extrusion of a length of the starting product, equal to that of the first weather strip part (S1a), the width of the slit (6) in the starting product (S1') is increased and such starting product for the second weather strip part (S1b) is deformed while passing the first forming roller (9), partly to deform the starting product (S1') and simultaneously to narrow the width of the spread slit (6) and in that the partly deformed starting product is caused to pass a second forming roll (11), downstream of the first forming roll (9) to close the hollow portion of the second weather strip part (S1b) to form the seam (5) in the second weather strip hollow portion, the hollow portion of the second weather strip part having a cross-sectional area, an outer circumferential length and an inner circumferential length less than the equivalent dimensional parameters of the hollow portion of the first weather strip part. A process according to claim 6, wherein said starting product (S1') is partly cut off along said slit (6) before passing said first forming roll (9). A process according to claim 6 or 7, wherein the further step is provided of conditioning or planing the surface of said weather strip after forming said seam on said weather strip. A process of manufacturing an irregularly-shaped weather strip comprising a first weather strip part (S1a) having a first cross-sectional area and at least one second weather strip part (S1b) integrally formed end-to-end with said first weather strip part (S1a) and having a second cross-sectional area, comprising the steps of extruding a moulding material from an extruding opening (70a) formed on a moulding die (50) to produce a starting product of the weather strip (S1) including a hollow portion, said starting product being provided with a slit extending longitudinally thereof with part of the starting product (S1'') having material removed from said slit along a length equivalent to the second weather strip part prior to the sides of the slit being brought together to form a longitudinal seam with the second longitudinal part (S1b) having a smaller cross-sectional area than the first longitudinal part (S1a), characterised in that after a length of the starting product (S1'') equal to that of the first weather strip portion part (S1a) is unslit and after it has been extruded, a longitudinal slit is cut in the wall surrounding the hollow portion of the starting product (S1'') to form the second part (S1b) of the weather strip, said strip of starting product (S1'') being passed through a forming opening (110) provided on a forming die (80,90,120) to deform the slitted starting product to form the second weather strip part (S1b) with the hollow portion thereof having a cross-sectional area, an outer circumferential length, and an inner circumferential length less than the equivalent dimensional parameters of the hollow portion of the first weather strip part (S1a) and simultaneously to close the slit for forming a seam on the hollow portion of the weather strip part. Apparatus for manufacturing an irregularly-shaped weather strip comprising a first weather strip part (S1a) having a first cross-sectional shape and at least one second hollow weather strip part (S1b) integrally formed end-to-end with said first weather strip portion and having a second cross-sectional shape, comprising: a moulding die (5) having an opening (7); a core member (8) inserted in said opening (7) of said moulding die (5), said core member (8) cooperating with said moulding die (5) to form an extruding opening (7a) therebetween for moulding a starting product (S1') of the weather strip having a hollow portion; slit forming means (P,13) for providing a longitudinal slit (6) of variable width through said starting product (S1') and forming walls for bringing the edges of the slit (6) together and joining them to form a longitudinal seam (15); characterised in that a projection (P) projects into said opening (7) and has an edge contacted by said core (8) whereby said projection (P) is adapted to provide the slit (6) through the wall of the hollow portion of said starting product (S1'), in that the forming means also comprises a cutter (13) capable of cutting material (18) from the starting product (S1'') for widening the slit (6), and in that said core member (8) projects from the front surface of said moulding die (5) over a desired length, the projecting portion of said core member (5) being provided with shoulder portions (8a,8b) forwardly to diminish the circumferential length of said core member, a first forming roll (9) being positioned adjacent to said upstream shoulder portion (8a) for closing the slit (6) when forming the first weather strip part (S1a); and a second forming roll (11) for closing the slit (6) when forming the second weather strip part (S1b) being positioned adjacent to said downstream shoulder portion (8b) so as to be movable toward and away from said downstream shoulder portion (8b). Apparatus as claimed in claim 10, further comprising a conditioning roll (16). Apparatus as claimed in claim 10 or 11, further comprising a planing roll (17) for smoothing the seam (15) after the joining of the edges of said slit (6). Apparatus as claimed in claim 10, 11 or 12, wherein two of said second forming rolls (11) are provided. Apparatus for manufacturing an irregularly-shaped weather strip (S1) comprising a first weather strip part (S1a) having a first cross-sectional shape and at least one second weather strip part (S1b) integrally formed end-to-end with said first weather strip part (S1a) and having a second cross-sectional shape, the weather strip (S1) having a hollow portion extending lengthwise thereof, the apparatus comprising: a moulding die (50) having an opening (70); a core member (120) inserted in said opening (70) of said moulding die (50, said core member (120) cooperating with said moulding die (50) to form an annular extruding opening (70a) therebetween for moulding a starting member (S1'') of a weather strip (S1) having a hollow portion extending lengthwise thereof; cutter means (150) partly to cut material from that portion of said starting member (S1'') to form said second weather strip part (S1b) for forming a slit (160) therethrough, and means (80,90) for joining the edges of said slit (160), characterised in that said core member (120) projects from the front surface of said moulding die (50) over a desired length, the projected portion of said core member (120) being provided with a shoulder portion (120a) forwardly to diminish the circumferential length of said core member; first and second forming dies (80,90), the second die being engageable with the first forming die, are positioned in alignment with said shoulder portion (120a) of said core member (120); said first and second forming dies (80,90) being cooperable with said core member (120) to form an annular forming opening (110) when said first forming die (80) is completely engaged by said second forming die (90), and in that the outer configuration of said forming opening (110) at the rear surface of said engaged forming dies (80,90) is different from that at the front surface of said engaged forming dies. Apparatus as claimed in claim 14, wherein said second forming die is divided into two parts (220,230). Apparatus as claimed in claim 14 or 15, further comprising as said cutter means a cutting die (270) to cut off a part of said starting member (S1'').

Inventors: ARIMA HIDETOSHI, ARIMA, HIDETOSHI
Applicants: TOKAI KOGYO CO LTD, TOKAI KOGYO KABUSHIKI KAISHA
Application year: 1990
Main classification: B60J10
IPC codes: B29C47, B60J10