Utility Vehicle

This application claims priority to Japanese Patent Application No. 2024-061327 filed Apr. 5, 2024, the disclosure of which is hereby incorporated by reference in its entirety.

The present invention relates to a utility vehicle including a muffler configured to reduce exhaust noise of the engine.

Japanese Patent No. 6655970 discloses a utility vehicle including a cargo box at a back portion of the vehicle body, an engine below the cargo box, and a muffler configured to reduce exhaust noise of the engine.

The above utility vehicle includes a muffler cover attached to and held by the body frame or the muffler to reduce heat transferred from the muffler to the cargo box above the muffler or other components around the muffler. Attaching the muffler cover to the body frame requires the cargo box to be high in position to secure the distance between (i) the muffler cover and engine accessories and (ii) the cargo box, thereby making it difficult to load and unload a cargo. Attaching the muffler cover to the muffler causes the muffler cover to cover the entire muffler and capture heat from the muffler inside, thereby overheating, for example, the surface of the muffler cover. Further, the muffler cover held by the muffler lets rattling noise be made by two or more muffler cover segments bolted to each other.

The present invention provides a utility vehicle including a muffler cover that does not require the cargo box to be high in position, that is not overheated, and that causes no rattling noise.

A utility vehicle according to the present invention includes: a body of the utility vehicle; a cargo box at a back portion of the body; an engine below the cargo box; a muffler disposed below the cargo box and configured to reduce exhaust noise of the engine; and a muffler cover covering the muffler and including: an upper cover segment covering an upper portion of the muffler; and a lower cover segment covering a lower portion of the muffler, the upper cover segment and the lower cover segment being separately attached to the muffler and apart from each other.

The above configuration allows the upper and lower cover segments to be attached to and held by the muffler separately and as uncoupled from each other. This allows the muffler cover to cover the muffler without causing rattling noise or requiring the cargo box to be high in position.

With the above configuration, the upper and lower cover segments to be apart from each other by a gap for letting heat from the muffler escape from the muffler cover, preventing heat from remaining inside the muffler cover and thereby preventing the muffler cover from being overheated.

The utility vehicle may preferably be configured such that the upper cover segment has a first length along a length of the muffler which first length is larger than the length of the muffler, and the lower cover segment has a second length along the length of the muffler which second length is smaller than the length of the muffler.

With the above configuration, the upper cover segment covers an upper portion of the muffler over its entire length, whereas the lower cover segment covers a lower portion of the muffler over a length smaller than the entire length of the muffler. The above configuration thus uses the upper cover segment to reduce heat transferred from the muffler upward, for example, to the cargo box, and allows heat to be easily dissipated from the muffler downward to prevent heat from remaining inside the muffler cover.

The utility vehicle may preferably be configured such that the lower cover segment corresponds in position to a portion of the muffler which portion is between a lengthwise center of the muffler and a front end of the muffler.

With the above configuration, the lower cover segment covers a front end portion of the muffler from below which front end portion tends to be heated by exhaust gas from the engine. This inhibits engine accessories below the muffler from being heated by heat dissipated by the muffler.

The description below deals with an example embodiment of the present invention with reference to drawings.

The embodiment described below is a utility vehicle.show arrow F to indicate the forward direction relative to the vehicle body and arrow B to indicate the backward direction relative to the vehicle body.show arrow U to indicate the upward direction relative to the vehicle body and arrow D to indicate the downward direction relative to the vehicle body.shows arrow L to indicate the leftward direction relative to the vehicle body, which corresponds to the front side of, and arrow R to indicate the rightward direction relative to the vehicle body, which corresponds to the back side of. The lateral direction relative to the body corresponds to the width of the vehicle body.

illustrates a utility vehicle for multiple purposes such as cargo transport and recreation. The utility vehicle includes a body frame, a pair of left and right front wheels, a pair of left and right rear wheels, and a body. The front wheelsare held by a front portion of the body frame, and are turnable and drivable. The rear wheelsare held by a back portion of the body frame, and are drivable. The utility vehicle includes a driver sectiondisposed at a portion of the bodywhich portion is between the front wheelsand the rear wheels. The driver sectionincludes a front driver sectionA, a back driver sectionB, and a roll-over protective structure (ROPS)that defines respective driver spaces of the front and back driver sectionsA andB. The front driver sectionA includes a driver's seatand a steering wheelfor use to change the direction of the front wheels. The utility vehicle includes a cargo boxand a motor sectionat a back portion of the body.

The motor sectionis, as illustrated in, below the cargo boxand, as illustrated in, includes an engine, a continuously variable transmission device, and a transmission. The continuously variable transmission deviceis configured to receive motive power from the engineand continuously vary the motive power. The transmissionis configured to receive motive power from the continuously variable transmission device, adjust the motive power with use of gears, and transmit the resulting motive power to the front and rear wheelsand. The continuously variable transmission deviceis coupled to respective lateral portions of the engineand the transmission. The continuously variable transmission deviceincludes an endless rotary belt (not illustrated in the drawings) and belt pulleys (not illustrated in the drawings) each with an adjustable belt winding diameter to vary received motive power. The transmissionis backward of the engine.

As illustrated in, the motor sectionincludes an exhaust ductextending from the engine, a first mufflerconnected to the exhaust duct, and a second mufflerconnected to the first muffler. As illustrated in, the second mufflerincludes two attachment sectionsat a lower back portion. The transmissionincludes a supportwith which the attachment sectionsare locked. The transmissionholds a back portion of the second muffler. The enginedischarges exhaust gas through the exhaust ductinto the first muffler, which cleans the exhaust gas with use of a catalyst and discharges the resulting exhaust gas into the second muffler, which discharges the exhaust gas through a discharge cylinder(see) while muffling exhaust noise.

Exhaust Duct The exhaust duct, as illustrated in, includes (i) two upstream exhaust duct sectionsconnected to respective exhaust sectionsof the engineand (ii) a downstream exhaust duct sectionmerging the upstream exhaust duct sectionswith each other and connecting the upstream exhaust duct sectionsto the first mufflerand provided with a COsensorconfigured to detect carbon dioxide discharged from the engine.

The upstream exhaust duct sectionsextend from the respective exhaust sectionsforward relative to the body, then leftward relative to the body along its width, and then backward relative to the body in the front-back direction (hereinafter referred to as “lengthwise”) relative to the body to reach the downstream exhaust duct section. The upstream exhaust duct sectionsare arranged vertically relative to the body. The upstream exhaust duct sections, specifically, each include (i) a starting end portionand a terminal end portioneach extending lengthwise relative to the body and (ii) an intermediate portioninterposed between the starting and terminal end portionsandand extending widthwise relative to the body. The intermediate portionand terminal end portionof each upstream exhaust duct sectionare arranged vertically relative to the body. The upstream exhaust duct sectionsmay alternatively be arranged lengthwise or widthwise relative to the body.

As illustrated in, the downstream exhaust duct sectionis backward of the upstream exhaust duct sectionsand extends lengthwise relative to the body.

Exhaust Duct Cover and First Muffler Cover As illustrated in, the motor sectionincludes an exhaust duct covercovering the exhaust ductand configured to reduce the amount of heat that the exhaust ductdissipates and that is transferred to, for example, the cargo box. The motor sectionincludes a first muffler covercovering the first mufflerand configured to reduce the amount of heat that the first mufflerdissipates and that is transferred to, for example, the cargo box. As illustrated in, the motor sectionincludes a second muffler covercovering the second mufflerand configured to reduce the amount of heat that the second mufflerdissipates and that is transferred to, for example, the cargo box.

As illustrated in, the exhaust duct cover, which covers the exhaust duct, covers both the upstream exhaust duct sectionsand the downstream exhaust duct section. The exhaust duct coverfor the present embodiment covers only the intermediate portionand terminal end portionof each upstream exhaust duct sectionand the entire downstream exhaust duct section. The exhaust duct covermay alternatively cover the entire upstream exhaust duct sections.

The exhaust duct cover, as illustrated in, includes two exhaust duct cover segmentsopposite to each other across the diameter of each of the upstream exhaust duct sectionsand the downstream exhaust duct section. The exhaust duct coverfor the present embodiment includes a pair of upper and lower exhaust duct cover segmentsopposite to each other across the diameter of each of the upstream exhaust duct sectionsand the downstream exhaust duct section.

The description below assumes that the exhaust duct coverincludes a first exhaust duct cover segmentand a second exhaust duct cover segment

As illustrated in, the first exhaust duct cover segmentcovers the upstream and downstream exhaust duct sectionsandfrom above, whereas the second exhaust duct cover segmentcovers the upstream and downstream exhaust duct sectionsandfrom below. The first exhaust duct cover segmenthas an opening through which the COsensorprotrudes.

As illustrated in, the first muffler cover, which covers the first muffler, includes two muffler cover segmentsopposite to each other across the diameter of the first muffler. The first muffler coverfor the present embodiment includes a pair of upper and lower muffler cover segmentsopposite to each other across the diameter of the first muffler.

The description below assumes that the first muffler coverincludes a first muffler cover segmentand a second muffler cover segment

As illustrated in, the first muffler cover segmentcovers the first mufflerfrom above, whereas the second muffler cover segmentcovers the first mufflerfrom below. As illustrated in, the first mufflerincludes an exhaust port, and the second muffler cover segmenthas a back portion provided with an exhaust port coverintegral with the second muffler cover segmentand covering the exhaust portfrom below.

As illustrated in, the first muffler cover segmentis integral with the first exhaust duct cover segment, whereas the second muffler cover segmentis integral with the second exhaust duct cover segment

The exhaust duct coverand the first muffler coverare attached respectively to the exhaust ductand the first muffleron the basis of a structure illustrated in drawings such as.

The motor section, as illustrated in, includes a first supportattached to the upstream exhaust duct sections, a second supportattached to the downstream exhaust duct section, and a third supportattached to the exhaust portof the first muffler.

Specifically, as illustrated in, the first supportis a ring around the respective intermediate portionsof the upstream exhaust duct sections. The first supportincludes two arch-shaped first support segments including respective couplerswelded to the intermediate portions, so that the first supportis held by the upstream exhaust duct sectionswith use of the couplers

As illustrated in, the second supportis a ring around the downstream exhaust duct section, and includes two arch-shaped second support segments including respective couplerswelded to the downstream exhaust duct section, so that the second supportis held by the downstream exhaust duct sectionwith use of the couplers

As illustrated in, the third supportis a ring around the exhaust portof the first muffler, and includes two arch-shaped third support segments including respective couplerswelded to the exhaust port, so that the third supportis held by the first mufflerwith use of the couplers

As illustrated in, the motor sectionincludes a first fastening bandand a second fastening bandeach serving to attach the exhaust duct coverto the exhaust ductand a third fastening bandserving to attach the first muffler coverto the first muffler. The exhaust duct coverand the first muffler coverare attached respectively to the exhaust ductand the first muffleras illustrated in.

Specifically, the first exhaust duct cover segmentis placed above the upstream exhaust duct sectionsand the downstream exhaust duct sectionto bring an inner side portion into contact with the first and second supportsand, so that the first exhaust duct cover segmentis supported by the first and second supportsfrom inward. The second exhaust duct cover segmentis placed below the upstream exhaust duct sectionsand the downstream exhaust duct sectionto bring an inner side portion into contact with the first and second supportsand, so that the second exhaust duct cover segmentis supported by the first and second supportsfrom inward.

As illustrated in, the first fastening bandis fitted around respective portions of the first and second exhaust duct cover segmentsandwhich portions correspond to the first supportand is fastened with use of a fastening screwto fix the first and second exhaust duct cover segmentsandto the first support. As illustrated in, the second fastening bandis fitted around respective portions of the first and second exhaust duct cover segmentsandwhich portions correspond to the second supportand is fastened with use of a fastening screwto fix the first and second exhaust duct cover segmentsandto the second support. The exhaust duct coveris attached to the exhaust ductwith use of the first and second fastening bandsandand the first and second supportsand. As illustrated in, the first exhaust duct cover segmentis provided with two fixing membersfor fixing the respective first and second fastening bandsandfrom outward to prevent displacement.

The first muffler cover segmentis placed above the first mufflerto bring an inner side portion into contact with the third support, so that the first muffler cover segmentis supported by the third supportfrom inward. This placement is simultaneous with the placement of the first exhaust duct cover segmentabove the upstream exhaust duct sectionsand the downstream exhaust duct sectionto be supported by the first and second supportsand. The second muffler cover segmentis placed below the first mufflerto bring an inner side portion into contact with the third support, so that the second muffler cover segmentis supported by the third supportfrom inward. This placement is simultaneous with the placement of the second exhaust duct cover segmentbelow the upstream exhaust duct sectionsand the downstream exhaust duct sectionto be supported by the first and second supportsand.

As illustrated in, the third fastening bandis fitted around respective portions of the first and second muffler cover segmentsandwhich portions correspond to the third supportand is fastened with use of a fastening screw(see) to fix the first and second muffler cover segmentsandto the third support. The first muffler coveris attached to the first mufflerwith use of the second and third fastening bandsandand the second and third supportsand. As illustrated in, the first muffler cover segmentis provided with a fixing memberfor fixing the third fastening bandfrom outward to prevent displacement.

As illustrated in, the second muffler cover, which covers the second muffler, includes an upper cover segmentand a lower cover segment.

As illustrated in, the upper cover segmentextends circumferentially around an upper portion of the second muffler. As illustrated in drawings such as, the second mufflerhas an upper circumferential portion provided with two or more upper cover supportsto which the upper cover segmentis attached with use of respective coupling bolts. The upper cover segmentis held by the second mufflerin such a manner as to cover an upper portion of the second muffler.

As illustrated in, the lower cover segmentis below a lower portion of the second muffler. As illustrated in drawings such as, the second mufflerhas a lower circumferential portion provided with two or more lower cover supportsto which the lower cover segmentis attached with use of respective coupling bolts. The lower cover segmentis held by the second mufflerin such a manner as to cover a lower portion of the second muffler.

As illustrated in, the upper and lower cover segmentsandare separately attached to the second mufflerwith gapsbetween the upper and lower cover segmentsandwhich gapsserve to let heat dissipated by the second mufflerescape from the second muffler cover.

As illustrated in, the upper cover segmenthas a length Lalong the length of the second muffler, whereas the second mufflerhas a length L, the length Lbeing larger than the length L. The lower cover segmenthas a length Lalong the length of the second mufflerwhich length Lis smaller than the length L. The upper cover segmentcovers the second mufflerover its entire length, whereas the lower cover segmentcovers the second mufflerover a length smaller than the entire length of the second muffler.

As illustrated in, the lower cover segmentcorresponds in position to a portion of the second mufflerwhich portion is between its lengthwise center C and its front end. The lower cover segmentcovers a front end portion of the second mufflerfrom below which front end portion tends to be heated by exhaust gas from the engine.

(1) The embodiment described above is an example in which the upper cover segmenthas a length Llarger than the length Lof the second muffler. The present invention is, however, not limited to such a configuration: The length Lmay be equal to or smaller than the length L.

(2) The embodiment described above is an example in which the lower cover segmenthas a length Lsmaller than the length Lof the second muffler. The present invention is, however, not limited to such a configuration: The length Lmay be larger than or equal to the length L.

(3) The embodiment described above is an example in which the lower cover segmentis between the center C of the second mufflerand its front end. The present invention is, however, not limited to such a configuration: The lower cover segmentmay be between the center C of the second mufflerand its back end.

(4) The embodiment described above includes a first muffler, but may alternatively exclude the first muffler.

(5) The embodiment described above includes an exhaust duct coverand a first muffler cover, but may alternatively exclude the exhaust duct coverand the first muffler cover.