JP6769815B2 - Manufacturing method of foam molded product, foam molded product and bumper absorber - Google Patents

Description

The present invention relates to a method for producing a foam molded product, a foam molded product, and a bumper absorber.

A bumper absorber, which is a foam molded body, is arranged in the bumper of the vehicle as a shock absorbing member. In recent years, a tube-type collision detection device for vehicles has been proposed that detects a collision with a pedestrian or the like by using a tube member arranged in a groove of a bumper absorber. For example, a vehicle collision in which a detection tube is housed in a groove of a bumper absorber, and a holding portion for holding the detection tube is formed in a part of the groove on the upper side of the vehicle and the lower side of the vehicle in a part in the longitudinal direction. The detection device is disclosed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-279666

In the vehicle collision detection device described in Patent Document 1, a holding portion for holding the detection tube is formed in the groove portion of the bumper absorber on the upper side surface of the vehicle and the lower side surface of the vehicle in a part in the longitudinal direction. .. When a bumper absorber having a holding portion is formed by filling a mold with foam beads, air collects in a region at the tip of the holding portion, which is an opening end of the groove, and the foam beads do not wrap around well in the region. It may not be filled. As a result, the beads do not reach the protrusion-shaped holding portion (negative angle portion) formed at the opening end of the groove portion, so that the tube arranged in the groove portion of the bumper absorber may fall off without being held. There is. Therefore, in order to preferably hold the tube or the like arranged in the foam molded body such as the bumper absorber, the generation of air pools in the above region is suppressed, and the bead can be sufficiently introduced to the negative angle portion. A method for producing a foam molded product such as an absorber is desired.

The present invention has been made in view of the above-mentioned conventional problems, and is a method for producing a foamed molded article capable of suppressing air accumulation in a negative corner portion and introducing foamed beads to the negative corner portion, and a negative angle portion. It is an object of the present invention to provide a foam molded article and a bumper absorber in which foam beads are introduced up to a corner portion (undercut portion).

In the method for producing a foamed molded product according to claim 1, a mold for molding a foamed molded product having a groove and having a protruding negative angle portion (undercut portion) at an opening end portion on both side surfaces of the groove portion. When the foam beads are filled inside, the air in the region is discharged from the hole provided in the mold so as to face the region where the opposite surface of the negative angle portion is formed in the mold, and the inside of the mold is filled. filled the foamed beads were heat sealing to produce a foamed molded article, the expanded molded, respectively provided on opposite surfaces of the negative angle portion, to have a protruding portion attributed to the hole ..

According to the above configuration, when the foam beads are filled in the mold by discharging the air in the region where the negative angle portion (undercut portion) of the foamed molded product is formed in the mold from the holes provided in the mold. Foamed beads can be introduced into the region. As a result, in the foamed molded product obtained by the above-mentioned manufacturing method of the foamed molded product, the air accumulation in the negative corner portion (undercut portion) is suppressed and the foamed beads reach the negative corner portion (undercut portion). , The tube or the like arranged in the groove of the foamed molded product is prevented from falling off.
Further, in the method for producing a foam molded product, a foam molded product having a protrusion due to a hole (for example, a bumper absorber) may be produced. With this configuration, it is possible to more preferably suppress the tube or the like arranged in the groove of the foamed molded product from falling off.

According to the present invention, a method for producing a foamed molded article capable of suppressing air accumulation in a negative angle portion and introducing foamed beads to the negative angle portion (undercut portion), and a negative angle portion (undercut portion). It is possible to provide a foam molded product and a bumper absorber into which foam beads have been introduced.

It is sectional drawing which shows that the bumper absorber is molded using a pair of molds consisting of a concave mold and a convex mold in the manufacturing method of the bumper absorber which concerns on one Embodiment of this invention. (A) is a sectional view of a concave type and a convex type used in the method for manufacturing a bumper absorber according to an embodiment of the present invention, and (b) is a sectional view of the concave type and the convex type when the concave type and the convex type are molded. c) is an enlarged view of the dotted line portion of (a). It is a schematic block diagram of the bumper absorber obtained by one Embodiment of this invention. (A) is a sectional view taken along line AA of the bumper absorber shown in FIG. 3, (b) is a sectional view taken along line BB of the bumper absorber shown in FIG. 3, and (c) is a protruding portion at a negative angle. It is a cross-sectional view taken along the line AA of the bumper absorber shown in FIG. 3 in the case where is formed. It is sectional drawing of the bumper absorber obtained by another embodiment of this invention. It is sectional drawing which shows that the bumper absorber is molded using a pair of molds consisting of a concave mold and a convex mold in the manufacturing method of the bumper absorber which is the comparison object of this invention.

In the present specification, the numerical range indicated by using "~" indicates a range including the numerical values before and after "~" as the minimum value and the maximum value, respectively.

Hereinafter, embodiments of the method for producing a foamed molded article of the present invention will be described in detail.

Hereinafter, a method for producing a foam molded article according to an embodiment of the present invention will be described. The method for producing an effervescent molded product of the present embodiment includes a groove portion, and is provided in a mold for forming a foam molded product having a protruding negative angle portion (undercut portion) at an opening end portion on both side surfaces of the groove portion. When the foamed beads are filled, the air in the region is discharged from the holes provided in the mold so as to face the region in which the negative angle portion is formed in the mold, and the foam filled in the mold. The beads are heat-fused to produce a foamed molded product.

In the method for producing a foamed molded product of the present embodiment, air in a region where a negative angle portion (undercut portion) of the foamed molded product is formed in the mold is discharged from a hole provided in the mold into the mold. Foam beads can be introduced into the region when filling the foam beads. As a result, in the foamed molded product obtained in the present embodiment, air accumulation in the negative corner portion (undercut portion) is suppressed, and the foam beads are thoroughly (filled) in the negative corner portion (undercut portion). Therefore, it is possible to prevent the tube arranged in the groove of the foamed molded product from falling off. Therefore, for example, it is possible to obtain a bumper absorber which is a foam molded product capable of preferably holding a tube in a groove.

<Manufacturing method of bumper absorber>
Hereinafter, the method for producing the foam molded product of the present embodiment will be described in more detail. In the following embodiment, the method of molding the bumper absorber, which is a foam molded product, will be described with reference to the drawings, but the foam molded product is not limited to the bumper absorber.

In the method for manufacturing a bumper absorber of the present embodiment, for example, the bumper absorber 10 is molded by using a pair of molds consisting of a concave mold 1 having a concave shape and a convex mold 2 having a convex shape as shown in FIGS. To do. Specifically, as shown in FIG. 1, a pair of molds composed of a concave mold 1 and a convex mold 2 is filled with foam beads, and the foam beads filled in the pair of molds are heat-sealed to be negative. A bumper absorber 10 having corner portions (undercut portions) 10A and 10B can be formed. The pair of molds 1 and 2 can be mounted on an in-mold foam molding machine by a conventionally known method and used.

As shown in FIG. 2A, the concave mold 1 is a mold having a concave shape, and the convex mold 2 is a mold having a convex shape. As shown in FIG. 2B, a pair of molds composed of a concave mold 1 and a convex mold 2 is molded to form a molding space 3 in the pair of molds. Further, the molding space 3 formed in the pair of molds by mold clamping is filled with foamed beads, and the foamed beads filled in the pair of molds are heated and fused to form a negative angle portion (undercut portion). The bumper absorber 10 provided with 10A and 10B is molded.

The concave mold 1 has a concave shape, and the molding space 3 for molding the bumper absorber 10 having the negative angle portions (undercut portions) 10A and 10B is formed by molding with the convex mold 2. There is no particular limitation. Further, the concave shape 1 has a filling hole (not shown) for filling the molding space 3 for molding the bumper absorber 10 with foamed beads, and a supply hole for supplying steam for heating, foaming and fusing the foamed beads to each other. (Not shown), the molding space 3 may be provided with an exhaust hole or the like for discharging the air in the molding space 3 such as the pumped air used when filling the foam beads.

The convex mold 2 has a convex shape, and the molding space 3 for molding the bumper absorber 10 having the negative angle portions (undercut portions) 10A and 10B is formed by molding with the concave mold 1. There is no particular limitation. For example, the convex shape 2 has groove portions 2c and 2d for forming negative angle portions (undercut portions) 10A and 10B in the bumper absorber 10 on both side surfaces 2a and 2b of the convex shape. Further, in the grooves 2c and 2d, the side surfaces 2e and 2g of the convex shape on the tip direction side are inclined in the tip direction, and the lengths of the side surfaces 2e and 2g are in the direction opposite to the tip direction side of the convex shape. It is smaller than the length of the side surfaces 2f and 2h. Further, the convex shape 2 extends from the chamber surface C toward the tip of the convex shape, branches toward the bottom surface of the groove portions 2c and 2d, and penetrates from the chamber surface C of the convex shape 2 to the groove portions 2c and 2d through the discharge hole 2j. Be prepared. The chamber is a space for charging working fluids such as steam and cooling water in foam molding in the mold. In the present embodiment, the concave chamber 1A is on the back side of the concave mold 1 and the convex chamber 1A is convex on the back side of the convex mold 2. A mold chamber 2A is formed (see, for example, Japanese Patent Application Laid-Open No. 2001-79870).

The convex mold 2 is provided with the discharge hole 2j, so that when the concave mold 1 and the convex mold 2 are molded, the groove portions 2c and 2d which are the regions where the negative angle portions (undercut portions) 10A and 10B of the bumper absorber 10 are formed. The air can be exhausted. As a result, when the molding space 3 is filled with the foamed beads, the foamed beads can be suitably introduced into the groove portions 2c and 2d, and the air pool in the groove portions 2c and 2d can be suppressed. Therefore, by using the convex mold 2, it is possible to mold the bumper absorber 10 in which the tube is prevented from falling off when the tube is arranged in the groove portion. The discharge method is not particularly limited, and examples thereof include a method of sending air from the filling machine together with the foam beads into the mold and discharging the air by the pressure difference thereof, a method of discharging (sucking) with a decompression pump, and the like.

When the molding space 3 is filled with foamed beads, the molding space is formed from the discharge hole 2j provided in the concave mold 1 so as to face the region where the negative angle portions (undercut portions) 10A and 10B are formed in the pair of molds. The air in the region where the negative angle portions 10A and 10B of the bumper absorber 10 in No. 3 are formed is discharged.

The base resin constituting the foamed beads filled in the molding space 3 formed in the pair of the concave mold 1 and the convex mold 2 is not particularly limited, and is, for example, a polyolefin resin, a polystyrene resin, and a polystyrene resin. Examples include styrene-modified polyolefin-based resins. Among these, the use of a polyolefin resin is preferable from the viewpoints of cushioning property, chemical resistance, heat resistance, strain recovery rate after compression, and easy recycling.

The polyolefin-based resin is not particularly limited, and examples thereof include polypropylene-based resins and polyethylene-based resins. Examples of polypropylene-based resins include propylene homopolymers, ethylene / propylene copolymers, ethylene / propylene / 1-butene copolymers, and the like. Examples of the polyethylene-based resin include high-density polyethylene-based resin, medium-density polyethylene-based resin, low-density polyethylene-based resin, linear low-density polyethylene-based resin, and more specifically, ethylene / 1-butene co-weight. Combined, ethylene / 4-methyl-1-pentene copolymer and the like can be mentioned. The above-mentioned copolymer may be a random copolymer or a block copolymer.
The method for producing the foamed beads is not particularly limited, and conventionally known production methods can be mentioned. As an example, in the case of polyolefin-based resin foam beads (foamed particles), the production methods disclosed in International Publication No. 2009/075208, JP-A-2006-117842, etc. can be mentioned, and polystyrene-based resin foam beads can be used. For example, the production methods disclosed in JP-A-2003-201360, JP-A-2014-118474, etc. can be mentioned (described as "preliminary foamed particles" in the patent document), and styrene modified. Quality Polyolefin-based resin foamed beads (foamed particles) include, but are not limited to, the production methods disclosed in JP-A-2008-239794 and the like.
The foamed beads thus obtained can appropriately contain or coat additives such as flame retardants, antistatic agents, and colorants by a conventionally known method.
The particle size of the foamed beads is not particularly limited and may be, for example, 1 mm to 10 mm, but from the viewpoint of mold filling property, 1 mm to 5 mm is preferable, and 1 mm to 3 mm is more preferable.
The expansion ratio of the expanded beads is not particularly limited and may be, for example, 3 to 90 times, but from the viewpoint of mechanical strength and moldability, 5 to 60 times is preferable, and 5 to 40 times is preferable. Double is more preferable.
Such foamed beads are commercially available, for example, as Eperan-PP and Eperan-XL manufactured by Kaneka Corporation, and are easily available.

As a molding method (in-mold foam molding method) in the method for producing a foam molded article of the present invention, a conventionally known molding method described in JP-A-2001-79870 can be adopted. A pair of concave and convex molds are closed to form a molding space, foamed beads are sent from the raw material tank into the molding space through a filling device to fill the molding space, and then the foamed beads in the molding space are steamed. There is a method of heating with, fusing the foamed beads together, integrating them, and then cooling them, and then opening a pair of molds to take out the foamed molded product. More specifically, the description will be given according to the present embodiment or a comparison target.

After filling the molding space 3 with foamed beads, the foamed beads filled in the molding space 3 are heat-sealed to mold the bumper absorber 10. At this time, for example, water vapor may be supplied to the molding space 3 through a supply hole provided so as to penetrate the bottom surface of the concave mold 1, and the foamed beads may be heated, foamed (expanded), and fused to each other.

After the heating and fusion of the foamed beads filled in the molding space 3 is completed, the foamed beads are cooled, and the mold clamping of the pair of molds 1 and the convex mold 2 is released to take out the bumper absorber 10 which is a foamed molded product. be able to.

On the other hand, a method for producing a bumper absorber to be compared with the present invention will be described with reference to FIG. The pair of molds 21 and the convex 22 shown in FIG. 6 are different from the pair of molds 1 and 2 shown in FIGS. 1 and 2 in that the convex 22 is not provided with a discharge hole. To do. Further, FIG. 6 shows a case where the foamed beads are filled in the molding space formed from the concave mold 21 and the convex mold 22.

In the manufacturing method of the bumper absorber to be compared, since the convex type 22 having no discharge hole is used, when the foamed beads 31 are filled in the molding space formed from the concave type 21 and the convex type 22, the negative angle portion ( The air reservoir regions 3a and 3b, which are the undercut portions), are formed, and the foam beads 31 are not introduced into the air reservoir regions 3a and 3b, or the filling density of the foam beads 31 in the air reservoir regions 3a and 3b is other than the regions 3a and 3b. Is smaller than the area of. As a result, when the foamed beads 31 are filled in the molding space formed from the concave shape 21 and the convex mold 22 and then the foamed beads 31 are heat-sealed to form the bumper absorber, the foamed beads are formed in the negative angle portion (undercut portion). A bumper absorber is obtained in which 31 is not sufficiently perfect. However, in the method for manufacturing the bumper absorber of the present embodiment, as described above, it is possible to obtain a bumper absorber in which the foamed beads are sufficiently well-developed in the negative angle portion (undercut portion).

<Bumpa absorber>
The bumper absorber 10 obtained by the method for manufacturing the bumper absorber of the present embodiment has a concave groove portion 10a as shown in FIGS. 3 and 4A, and has an open end on the side surface 10b and 10c of the groove portion 10a. Negative angle portions (undercut portions) 10A and 10B having a protruding shape are provided. Note that FIGS. 3 and 4 show a state in which the tube 11 is arranged in the groove portion 10a of the bumper absorber 10. In FIG. 4, FIG. 4A is a sectional view taken along line AA of the bumper absorber shown in FIG. 3, and FIG. 4B is a sectional view taken along line BB of the bumper absorber shown in FIG. The bumper absorber obtained by the method for manufacturing a bumper absorber of the present embodiment may have at least a part of the structure shown in FIG. 4A in the longitudinal direction (left-right direction in FIG. 3), which will be described later. As described above, the structure shown in FIG. 4A and the structure shown in FIG. 4B may be provided in the longitudinal direction.

As shown in FIG. 4A, the tube 11 is brought into contact with the groove portion 10a of the bumper absorber 10 by bringing the tube 11 into contact with the bottom surface of the groove portion 10a of the bumper absorber 10 and the negative angle portions (undercut portions) 10A and 10B. Is arranged. At this time, since the foamed beads are well-developed in the negative angle portions (undercut portions) 10A and 10B of the bumper absorber 10, the tube 11 is suitably held by the groove portion 10a of the bumper absorber 10, and the tube 11 is held by the bumper absorber 10. It is suppressed to drop out from.
Further, as shown in FIG. 4C, a configuration in which a convex trace (protruding portion) 10d caused by the discharge hole 2j is formed on the facing surfaces of the negative angle portions (undercut portions) 10A and 10B is configured. This is a preferred embodiment because the tube 11 is more suppressed from falling off from the bumper absorber 10. The number of convex traces in one negative angle portion (undercut portion) also depends on the length of the negative angle portion (undercut portion) (the length of the negative angle portion in the longitudinal direction of the absorber in FIG. 3) and the like. However, 1 to 8 pieces are preferable, 2 to 5 pieces are more preferable, and 2 to 3 pieces are further preferable.

The bumper absorber 10 obtained by the method for manufacturing the bumper absorber of the present embodiment may be used, for example, in a vehicle collision detection device.

For example, the width of the protrusion-shaped tips of the negative angle portions (undercut portions) 10A and 10B in the bumper absorber 10 is 1.5 mm to 3 mm in the depth direction of the groove portion 10a, and the depth of the groove portion 10a is 10 mm to It may be 15 mm. The shape of the side surface and the bottom surface of the groove portion 10a excluding the negative angle portions 10A and 10B is not limited to a rectangular shape, and may be a polygonal shape, a circular shape, or the like.
The hole diameter of the discharge hole 2j is not particularly limited as long as the discharge hole can be formed, and is preferably 0.3 mm to 2 mm, more preferably 0.5 mm to 1.5 mm, and further preferably 0.8 mm to 0.8 mm. It is 1.2 mm. Within this range, air can be easily discharged, foam beads tend to be less likely to be clogged in the discharge holes, maintainability is improved, and the diameter and height of the convex traces described below ( Length) tends to be easy to control. The hole shape of the discharge hole 2j is not limited to a circular shape, and may be a rectangular shape, a polygonal shape, or the like. The convex trace of the discharge hole depends on the hole shape of the mold surface of the discharge hole 2j. For example, if the hole shape of the mold surface is circular, the convex trace becomes close to a cylindrical shape and its diameter is large. It is preferably 0.3 mm to 2 mm, more preferably 0.5 mm to 1.5 mm, and even more preferably 0.8 mm to 1.2 mm. The height (length) of the cylindrical shape is preferably 0.1 mm to 5 mm, more preferably 0.5 mm to 3 mm, and further preferably 1 mm to 2 mm.

Further, when the tube 11 is brought into contact with the bottom surface and the negative angle portion (undercut portion) 10A and 10B of the groove portion 10a of the bumper absorber 10 and the tube 11 is arranged in the groove portion 10a, the outer wall surface and the groove portion of the tube 11 It is preferable that a gap is formed between the side surface 10b of the 10a and the bottom surface of the groove portion 10a, and between the outer wall surface of the tube 11 and the side surface 10c of the groove portion 10a and the bottom surface of the groove portion 10a. For example, as shown in FIG. 4A, a gap is formed on the upper side surrounded by the outer wall surface of the tube 11, the side surface 10b of the groove portion 10a, and the bottom surface of the groove portion 10a, and the outer wall surface of the tube 11 and the groove portion 10a are formed. It is preferable that a gap formed between the side surface 10c and the bottom surface of the groove 10a is formed on the lower side. As a result, a gap in which the tube 11 is deformed is secured in the groove portion 10a of the bumper absorber 10. For example, when the bumper absorber 10 holding the tube 11 is used as a vehicle collision detection device, the vehicle and a pedestrian or the like The tube 11 is appropriately deformed (for example, deformed up and down) at the time of a collision, and the collision detection accuracy is excellent.

On the other hand, as shown in FIG. 5, when at least a part of the outer wall surface of the tube 11 is brought into contact with the wall surface of the groove portion of the bumper absorber 20 and the tube 11 is arranged in the groove portion, the outer wall surface and the groove portion of the tube 11 In the bumper absorber 20 in a form different from the above-described embodiment in which there is no or almost no gap between the wall surface and the wall surface, the gap in which the tube 11 is deformed is hardly secured in the groove. When the bumper absorber 20 is used as a vehicle collision detection device, the tube 11 may not be properly deformed when a vehicle collides with a pedestrian or the like, and the collision detection accuracy may decrease. Therefore, as shown in FIG. 4A, the bumper absorber has a deformable gap between the wall surface (bottom surface and side surface) of the groove portion 10a of the bumper absorber 10 and the outer wall surface of the tube 11. It is preferable that the tube 11 is brought into contact with the bottom surface of the groove portion 10a and the negative angle portions 10A and 10B of the 10 to hold the tube 11. In the bumper absorber 20 shown in FIG. 5, it is preferable that the material is soft so that the tube 11 can be easily deformed.

The tube 11 is a member held in the groove portion 10a of the bumper absorber 10. Examples of the material of the tube 11 include synthetic rubber such as ethylene propylene rubber and silicon rubber. The cross-sectional shape of the tube 11 is not limited to a circle, and may be a polygon such as a quadrangle.

Hereinafter, the configuration of the bumper absorber as viewed from the vertical direction (vertical direction of the vehicle) and the horizontal direction (vehicle width direction) will be described in more detail with reference to FIG. As shown in FIG. 3, the bumper absorber 10 has a groove formed along the left-right direction, and the tube 11 is arranged in the groove portion 10a formed along the left-right direction.

As shown in FIGS. 3 and 4A, the bumper absorber 10 has regions in which negative angle portions (undercut portions) 10A and 10B are formed on both side surfaces of the groove portions 10a formed along the left-right direction. A plurality of 5's may be provided along the left-right direction, and the plurality of regions 5 may be located at predetermined intervals. As a result, the bumper absorber 10 can more preferably hold the tube 11.

Further, as shown in FIGS. 3 and 4B, the bumper absorber 10 has a negative angle portion having a protrusion shape at the opening end portions of both side surfaces of the groove portion 10a formed along the left-right direction. A plurality of non-existing regions 6 may be provided along the left-right direction, and the plurality of regions 6 may be located at predetermined intervals. Since the negative angle portion (undercut portion) is not formed in the region 6, the tube 11 is not in contact with both side surfaces of the groove portion 10a in the region 6, and the outer wall surface of the tube 11 and the side surface of the groove portion 10a are in contact with each other. Gap 6a and 6b can be formed between them. As a result, for example, when the bumper absorber 10 holding the tube 11 is used as a vehicle collision detection device, the tube 11 is deformed more appropriately (for example, deformed up and down) when the vehicle collides with a pedestrian or the like, and the collision is detected. Better in accuracy.

Further, as shown in FIG. 3, the bumper absorber 10 is formed along the left-right direction with the region 5 in which the negative angle portions 10A and 10B are formed on both side surfaces of the groove portion 10a formed along the left-right direction. Regions 6 having a protrusion shape and not having a negative angle portion may be alternately provided along the left-right direction at the open end portions on both side surfaces of the groove portion 10a. As a result, when the bumper absorber 10 holds the tube 11 more preferably and the bumper absorber 10 holding the tube 11 is used as a vehicle collision detection device, the collision detection accuracy is more excellent.
Although the bumper absorber and its manufacturing method have been described above as an example of the foam molded product and its manufacturing method, the present invention is not limited thereto.

1 concave type 2 convex type 2j discharge hole (hole)
3 Molding space 10, 20 Bumper absorber (foam molded product)
10A, 10B Negative angle part 10d Convex trace (protruding part)

Claims (4)

When the foam beads are filled in a mold for molding a foam molded product having a groove portion and having a protruding negative angle portion (undercut portion) at the opening ends on both side surfaces of the groove portion, the said in the mold. The air in the region is discharged from the hole provided in the mold so as to face the region where the opposite surface of the negative angle portion (undercut portion) is formed.
The foamed beads filled in the mold are heat-fused to produce a foamed molded product.
The expanded molded article, respectively provided on opposite surfaces of the negative angle portion, the manufacturing method of the foamed molded to have a protrusion that attributed to the hole. The method for manufacturing a foamed molded product according to claim 1, wherein the protruding portions protrude from each other . The foam beads are heat-fused and fused,
A foam molded product having a groove portion, having a protruding negative angle portion at an opening end portion on both side surfaces of the groove portion, and having a protruding portion formed in the negative corner portion and projecting toward an opposite surface. The foam beads are heat-fused and fused,
A groove portion extending in the vehicle width direction is provided, a protrusion-shaped negative corner portion is provided at an opening end portion on both side surfaces of the groove portion, and a protrusion portion formed in the negative corner portion and projecting toward an opposing surface. Bumpa absorber equipped with.