| WO/2005/007364 | VEGETATION PRUNING DEVICE |
| WO/2005/006840 | VEGETATION PRUNING DEVICE |
| JP08312740 | POWER TRANSMISSION DEVICE AND PORTABLE TYPE WORKING MACHINE USING THE DEVICE |
KIM, Geon hee (466-42, Guro-dong Guro-gu, Seoul 152-050, KR)
| Claims [1] A portable saw, comprising: a driving rotating body which is rotatably provided in a first side of a saw body; an idle rotating body which is rotatably provided in a second side of the saw body; an endless chain belt which is connected with the driving rotating body and the idle rotating body; a connecting member whose first side is connected with the endless chain belt to move together with the endless chain belt and a second side has a projection to perform a linear movement in a linear area of the endless chain belt and a rotational movement in a curved area by being placed in a center of a radius of curvature of the endless chain belt; a saw blade which is coupled with the projection to reciprocate; a power transmitting means which is connected to the driving rotating body to transmit a rotational force; and a holder which is coupled with the saw body to fix a power input means connected to the power transmitting means. [2] The portable saw according to claim 1, wherein the endless chain belt comprises a chain, and the driving rotating body and the idle rotating body comprise chain sprockets. [3] The portable saw according to claim 1, wherein the endless chain belt comprises a timing belt, and the driving rotating body and the idle rotating body comprise timing pulleys. [4] The portable saw according to claim 1, wherein the endless chain belt comprises a metal belt which has grooves at predetermined intervals, and the driving rotating body and the idle rotating body comprise sprockets having teeth inserted into the grooves. [5] The portable saw according to one of claims 1 to 4, wherein the power transmitting means comprises a bevel gear which has an output bevel gear coupled with a central shaft of the driving rotating body and an input bevel gear rotatably provided in the holder to be engaged with the output bevel gear. [6] The portable saw according to claim 5, wherein the power input means comprises a rotating bar which has a spline rod rotatably provided in a grip bar and formed with a gear tooth in an end part in an axial direction, and the holder comprises a bar installation part having an installation hole to insert the grip bar thereinto and a fixing member fixing the grip bar inserted into the installation hole, and a seating member which is coupled with the saw body and has a space to accommodate the bevel gear therein. [7] The portable saw according to claim 6, wherein the input bevel gear comprises a spline insertion part which has a gear tooth in an axial direction to insert the spline rod in an internal circumference, and the bar installation part comprises an elastic gap formed in the installation hole and the fixing member comprises a fixing bolt to be coupled to the elastic gap. [8] The portable saw according to claim 5, wherein a guide means is provided in the saw body to guide a reciprocation movement of the saw blade. [9] The portable saw according to claim 8, wherein the guide means comprises a guide member which has a first side fixed to a front end part of the saw blade and is provided in a moving direction of the saw blade; a lateral guide roller member which is rotatably provided in the guide member and the saw blade to prevent the saw blade from shaking left and right; and an upper guide roller member which is rotatably provided in the guide member and the saw blade to prevent the saw blade from shaking up and down. [10] The portable saw according to claim 9, wherein the guide member comprises a fixing plate provided in the front end part of the saw body, a connecting plate having a first side connected to the fixing plate and a guide plate connected to a second side of the connecting plate and having a saw blade path therein; the lateral guide roller member comprises at least a pair of first lateral guide rollers facing each other in the front end part of the saw body and guiding opposite sides of the saw blade and at least a pair of second lateral guide rollers facing each other in the saw blade path of the guide plate and guiding the opposite sides of the saw blade, and the upper guide roller member comprises a first upper guide roller which is provided in the front end part of the saw body and adhered to an upper part of the saw blade and a second upper guide roller which is provided in the saw blade path of the guide plate and adhered to the upper part of the saw blade. [11] The portable saw according to claim 10, wherein a guide groove is depressed in opposite lateral sides of the saw blade in a lengthwise direction, and the first and second lateral guide rollers have guide rings in an external circumference to be inserted into the guide groove. |
Technical Field
[1] Apparatuses consistent with the present invention relate to a portable saw, and more particularly, to a portable saw which has a simple configuration, provides good cutting performance and is compatible with various devices by a reciprocating saw blade with a simple endless chain belt. Background Art
[2] While manual type saws had been used in logging or cutting down trees, a power saw has been widely used as it provides convenience and efficiency.
[3] The power saw is classified into a rotating power saw, a chain power saw and a crank type power saw depending on a driving method.
[4] A driving shaft of a motor in the rotating power saw is connected to a circular, rotating saw blade which rotates by a rotational force of the motor to cut off an object. The rotating power saw has a limited range of sizes in cutting off an object by employing the circular rotating saw blade. Also, the rotating power taw is less portable as it should be fixed to an additional workstation to be used.
[5] A chain type power saw cuts off an object by a rotating chain type saw blade mounted with a cutting bite. Even though the chain type power saw is highly portable, it employs a special saw blade, raising manufacturing costs. Also, as the cutting bite is exposed to the outside, there can be potential accidents.
[6] A crank type power saw includes a rotating wheel to rotate by a rotational force of a motor and a link to be connected with the rotating wheel to convert rotational movement into reciprocation movement and cut an object. However, if the reciprocating distance of the saw blade increases, the diameter of the rotating wheel should increase accordingly. As a result, the power saw becomes larger and portability deteriorates, causing a complex configuration and lowered cutting performance.
[7] The foregoing conventional power saws include an additional driving means such as a motor to drive the saw blade, increasing size and weight. Then, a user may not easily use the power saws which are not very portable. Also, the power saws require high manufacturing costs.
[8] In most cases, a weeder is used together with the power saw. For example, a user should remove scrubs and weeds at the same time while logging or forming and maintaining pasture. Thus, a user needs to have both a power saw and a weeder to work, causing inconvenience and raising costs. Disclosure of Invention Technical Problem
[9] Accordingly, it is an aspect of the present invention to provide a portable saw which has a simple configuration and provides good cutting performance by a reciprocating saw blade with a simple endless chain belt.
[10] Also, it is another aspect of the present invention to provide a portable saw which is affordable and easy to use by being installed in various driving devices even without an additional driving means.
[11] Further, it is another aspect of the present invention to provide a portable saw which is easily installed in a weeder to cut timber as well as removing weeds if necessary.
[12] Additional aspects and advantages of the general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the general inventive concept. Technical Solution
[13] The foregoing and/or other aspects of the present invention can be achieved by providing a portable saw comprising a driving rotating body which is rotatably provided in a first side of a saw body; an idle rotating body which is rotatably provided in a second side of the saw body; an endless chain belt which is connected with the driving rotating body and the idle rotating body; a connecting member whose first side is connected with the endless chain belt to move together with the endless chain belt and a second side has a projection to perform a linear movement in a linear area of the endless chain belt and a rotational movement in a curved area by being placed in a center of a radius of curvature of the endless chain belt; a saw blade which is coupled with the projection to reciprocate; a power transmitting means which is connected to the driving rotating body to transmit a rotational force; and a holder which is coupled with the saw body to fix a power input means connected to the power transmitting means.
[14] The endless chain belt comprises a chain, and the driving rotating body and the idle rotating body comprise chain sprockets.
[15] The endless chain belt comprises a timing belt, and the driving rotating body and the idle rotating body comprise timing pulleys.
[16] The endless chain belt comprises a metal belt which has grooves at predetermined intervals, and the driving rotating body and the idle rotating body comprise sprockets having teeth inserted into the grooves.
[17] The power transmitting means comprises a bevel gear which has an output bevel gear coupled with a central shaft of the driving rotating body and an input bevel gear rotatably provided in the holder to be engaged with the output bevel gear.
[18] The power input means comprises a rotating bar which has a spline rod rotatably provided in a grip bar and formed with a gear tooth in an end part in an axial direction, and the holder comprises a bar installation part having an installation hole to insert the grip bar thereinto and a fixing member fixing the grip bar inserted into the installation hole, and a seating member which is coupled with the saw body and has a space to accommodate the bevel gear therein.
[19] The input bevel gear comprises a spline insertion part which has a gear tooth in an axial direction to insert the spline rod in an internal circumference, and the bar installation part comprises an elastic gap formed in the installation hole and the fixing member comprises a fixing bolt to be coupled to the elastic gap.
[20] A guide means is provided in the saw body to guide a reciprocation movement of the saw blade.
[21] The guide means comprises a guide member which has a first side fixed to a front end part of the saw blade and is provided in a moving direction of the saw blade; a lateral guide roller member which is rotatably provided in the guide member and the saw blade to prevent the saw blade from shaking left and right; and an upper guide roller member which is rotatably provided in the guide member and the saw blade to prevent the saw blade from shaking up and down.
[22] The guide member comprises a fixing plate provided in the front end part of the saw body, a connecting plate having a first side connected to the fixing plate and a guide plate connected to a second side of the connecting plate and having a saw blade path therein; the lateral guide roller member comprises at least a pair of first lateral guide rollers facing each other in the front end part of the saw body and guiding opposite sides of the saw blade and at least a pair of second lateral guide rollers facing each other in the saw blade path of the guide plate and guiding the opposite sides of the saw blade, and the upper guide roller member comprises a first upper guide roller which is provided in the front end part of the saw body and adhered to an upper part of the saw blade and a second upper guide roller which is provided in the saw blade path of the guide plate and adhered to the upper part of the saw blade.
[23] A guide groove is depressed in opposite lateral sides of the saw blade in a lengthwise direction, and the first and second lateral guide rollers have guide rings in an external circumference to be inserted into the guide groove.
Advantageous Effects f 24] Α-'portaB-e. 1 saw h accordiηg to the present invention can< be compatibly <ϋsed by being connected to vaϋcious devices even without an addition " al,iMving means such.as a motor, .reducesf,s , ize';and weight by reciprocatmg;a,sa;w*ila v dB ayith an endlessjchaSn " bejt and a pair ofirotating bodies for 'portability and easy use/arid is'raanufactured'with affordable costs. [25] Particulariy, as the portable saw accordϊngto the presenύnvermon is.easily mounted in a/yveederremoving' weeds, it can, cut timber as;w.ell a^removirig weeds ey.en without an.additi(j|5ai f&ιwer-saw,
BrieTDescription of the Drawings
[26] These and other aspects and advantages of the present general inventive concept will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompany drawings of which:
[27] FIG. 1 is a perspective view of a portable saw according to an exemplary embodiment of the present invention;
[28] FIG. 2 is an exploded perspective view of the portable saw according to the exemplary embodiment of the present invention;
[29] FIG. 3 illustrates use of the portable saw according to the exemplary embodiment of the present invention;
[30] FIG. 4 is a schematic cross-sectional view of the portable saw according to the exemplary embodiment of the present invention;
[31] FIG. 5 is a longitudinal-sectional view to describe a guide structure of a saw blade of the portable saw according to the exemplary embodiment of the present invention; and
[32] FIGS. 6 A to 6C illustrate an endless chain belt, a driving rotating body and an idle rotating body which apply to the portable saw according to the exemplary embodiment of the present invention.
Best Mode for Carrying Out the Invention
[33] Reference will now be made in detail to the embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.
[34] FIG. 1 is a perspective view of a portable saw according to an exemplary embodiment of the present invention. FIG. 2 is an exploded perspective view of the portable saw according to the exemplary embodiment of the present invention. FIG. 3 illustrates use of the portable saw according to the exemplary embodiment of the present invention.
[35] Referring to FIGS. 1 and 2, a portable saw according to the exemplary embodiment of the present invention includes a saw body 110, a driving rotating body 120, an idle rotating body 130, an endless chain belt 140, a connecting member 150, a saw blade 160, a power transmitting means 170 and a holder 180.
[36] The portable saw according to the present invention receives power from an external power input means to be driven instead of having an additional power transmitting means such as a motor. Thus, the portable saw may be compatibly installed in various driving devices.
[37] A power input means 220 may vary as long as it transmits power to the power transmitting means 170. In the exemplary embodiment of the present invention, however, the power input means 220 is as in FIG. 3 to be connected with a weeder 200 that is widely used to remove weeds. For example, the weeder 200 includes an engine 210, the power input means 220 to transmit rotating power from the engine 210 to a driving part and a cutter rotatably connected to the power input means 220. The power input means 220 includes a grip bar 221 which is shaped like a pipe and a rotating bar 222 which is rotatably provided in the grip bar 221 and having a spline rod 222a formed with a gear tooth at an end part thereof in an axial direction. According to the present exemplary embodiment, after the cutter is removed from the weeder 200, the grip bar 221 of the power input means 220 is inserted into and fixed to the holder 180 (to be described later), and the rotating bar 222 is connected to the power transmitting means 170 to reciprocate the saw blade 160.
[38] Referring to FIG. 2, the saw body 110 accommodates therein the driving rotating body 120, the idle rotating body 130, the endless chain belt 140, the connecting member 150 and the saw blade 160 while the holder 180 having the power transmitting means 170 is connected to the saw body 110. The saw body 110 includes left and right saw bodies 111 and 112 which are separable.
[39] A replacement hole 113 may be formed in the saw body 110. The replacement hole
113 is elongated and formed in a lateral side of the saw body 110 to replace the saw blade 160 therethrough.
[40] The driving rotating body 120 is rotatably provided in a front of the saw body 110 to be rotated by power from the power transmitting means 170 while the idle rotating body 130 is rotatably provided in a rear side of the saw body 110.
[41] The endless chain belt 140 is connected between the driving rotating body 120 and the idle rotating body 130 and rotates by rotating force from the driving rotating body 120.
[42] The connecting member 150 converts rotational movement of the endless chain belt
140 to a translation motion to move the saw blade 160 back and forth. A first side of the connecting member 150 is connected to the endless chain belt 140 to move together therewith while a second side thereof is free and has a projection 151 connected to an internal end part of the saw blade 160.
[43] The connecting member 150 is installed toward a closed space formed by the endless chain belt 140. The projection 151 which is formed in the second side of the connecting member 150 performs a linear movement in a linear area of the endless chain belt 140 and a rotational movement in a curved area by being placed in a center of the radius of curvature of the endless chain belt 140. The projection 151 protrudes to be placed on a central line (a virtual line from a central shaft of the driving rotating body 120 to a central shaft of the idle rotating body 130) between the driving rotating body 120 and the idle rotating body 130.
[44] A cutting tooth 161 is formed in a lower side of a plate in a lengthwise direction of the saw blade 160 to perform a cutting operation. A projection insertion hole 162 is drilled in an internal end part of the saw blade 160 to insert the projection 151 of the connecting member 150 thereinto. Guide grooves 163 are formed in opposite lateral sides of the saw blade 160 in a lengthwise direction.
[45] The power transmitting means 170 transmits rotational force to the driving rotating body 120 and may vary as long as it rotates driving rotating body 120 by the power from the external power input means 220. Here, the power transmitting means 170 includes a bevel gear.
[46] The bevel gear includes an output bevel gear 171 which is coupled with a central shaft 121 of the driving rotating body 120 and an input bevel gear 172 which is rotatably provided in the holder 180 to be perpendicularly engaged with the output bevel gear 171. The input bevel gear 172 includes a spline insertion part 172a which has a gear tooth in an axial direction so as to insert the spline rod 222a of the power input means 220 therethrough.
[47] The holder 180 is coupled to the saw body 110 to fix the power input means 220 connected to the power transmitting means 170. The holder 180 includes a bar installation part 181 to connect the power input means 220 and a seating part 182 to be coupled with the saw body 110.
[48] The bar installation part 181 includes an installation hole 181a to insert the grip bar
221 of the power input means 220 thereinto and a fixing member 183 to fix the grip bar 221 inserted into the installation hole 181a. A bearing 184 is provided in the installation hole 181a to rotatably support the input bevel gear 172.
[49] The bar installation part 181 includes an elastic gap 185 which is cut and formed in the installation hole 181a while the fixing member 183 includes a fixing bolt to be coupled with the elastic gap 185. If the fixing bolt is fastened, the elastic gap 185 becomes smaller and the grip bar 221 inserted into the installation hole 181a is pressed and fixed. If the fixing bolt is unfastened, the elastic gap 185 widens and the grip bar 221 is released.
[50] The seating part 182 has a space to accommodate the bevel gear therein. A plurality of coupling holes is formed in a circumference of the seating part 182 to insert a coupling member 186 coupled to the saw body 110 thereinto. A bearing 187 is provided in the space of the sating part 182 to rotatably support the central shaft 121 of the driving rotating body 120. As the installation angle of the seating member 182 can be adjusted by changing a coupling direction when coupled with the saw body 110, the coupling angle of the power input means 220 may easily be adjusted. Mode for the Invention
[51] FIG. 4 is a schematic cross-sectional view of the portable saw according to the exemplary embodiment of the present invention. FIG. 5 is a longitudinal- sectional view to describe a guide structure of a saw blade 160 of the portable saw according to the exemplary embodiment of the present invention.
[52] Referring to FIGS. 2 and 4, the portable saw according to the present exemplary embodiment includes a guide means 190 to guide a reciprocation movement of the saw blade 160. The guide means 190 includes a guide member 191 whose first side is fixed to a front end part of the saw body 110 to be provided in a moving direction of the saw blade 160, a lateral guide roller member 192 which is rotatably provided in the guide member 191 and the saw body 110 to prevent the saw blade 160 from shaking left and right and an upper guide roller member 193 which is rotatably provided in the guide member 191 and the saw body 110 to prevent the saw blade 160 from shaking up and down.
[53] The guide member 191 includes a fixing plate 191a provided in the front end part of the saw body 110, a connecting plate 191b whose first side is connected to the fixing plate 191a and a guide plate 191c connected to a second side of the connecting plate 191b and having a saw blade path therein. The guide member 191a acts as a safety device protecting a user from the saw blade 160 while working, as well as guiding the movement of the saw blade 160.
[54] The lateral guide roller member 192 includes at least a pair of first lateral guide rollers 192a facing each other in the front end part of the saw body 110 and guiding lateral sides of the saw blade 160, and at least a pair of second lateral guide rollers 192b facing each other in the saw blade path of the guide plate 191c and guiding the lateral sides of the saw blade 160.
[55] The first and second lateral guide rollers 192a and 192b are engaged to the saw body
110 and the guide plate 191c while a guide ring 192c which is inserted into the guide grooves 163 of the saw blade 160 protrudes from an external circumference of the first and second lateral guide rollers 192a and 192b. As shown in FIG. 5, as the guide grooves 163 are asymmetrically inserted into lateral sides of the saw blade 160, the guide rings 192c are also asymmetrically formed in the first and second lateral guide rollers 192a and 192b.
[56] The upper guide roller member 193 includes a first upper guide roller 193a which is provided in the front end part of the saw body 110 and adhered to the upper part of the saw blade 160 and a second upper guide roller 193b which is provided in the saw blade path of the guide plate 191c and adhered to the upper part of the saw blade 160. The first and second upper guide rollers 193a and 193b have grooves in a center thereof to insert the upper part of the saw blade 160 thereinto. Steppers are formed in opposite sides of the grooves to prevent the saw blade 160 from being separated from the first and second upper guide rollers 193a and 193b.
[57] FIGS. 6A to 6C illustrate the endless chain belt 140, the driving rotating body 120 and the idle rotating body 130. FIG. 6 is a perspective view of an example of a chain driving method. FIG. 7 is a front view of an example of a timing belt driving method. FIG. 8 is a front view of an example of a metal belt driving method.
[58] As shown in FIG. 6, the endless chain belt 140 includes a chain 141 which is connected with the driving rotating body 120 and the idle rotating body 130. The driving rotating body 120 and the idle rotating body 130 include chain sprockets 121 and 131. The chain 141 can transmit power accurately, can be manufactured in a desired length and equipped with the connecting member 150. Thus, the chain 141 may be a representative example of the endless chain belt 140 according to the present invention.
[59] As shown in FIG. 7, the endless chain belt 140 includes a timing belt 142 which is connected with the driving rotating body 120 and the idle rotating body 130. The driving rotating body 120 and the idle rotating body 130 may include timing pulleys 122 and 132. The timing belt 142 generally includes an elastic material such as rubber. The timing belt 142 is closely adhered to the timing pulley so as to reduce noise and vibration.
[60] As shown in FIG. 8, the endless chain belt 140 includes a metal belt 143 which has grooves at predetermined intervals. The driving rotating body 120 and the idle rotating body 130 which are connected with the metal belt 143 may include sprockets 123 and 133 having teeth inserted into the grooves. The metal belt 143 includes a metal plate which is strong and elastic to thereby enhance strength and durability compared with the timing belt including rubber material.
[61] Hereinafter, the operation of the portable saw according to the exemplary embodiment of the present invention will be described.
[62] As shown in FIG. 3, after the cutter is removed from the weeder 200, the grip bar 221 is pressedly inserted into the installation hole 181a of the holder 180 so that the spline rod 222a of the rotation bar 222 is fitted in the spline insertion part 172a formed in the input bevel gear 172. Then, if the fixing member 183 is coupled to the grip bar 221, the elastic gap 185 of the holder 180 becomes smaller and the grip bar 221 is pressed and fixed to an internal circumference of the installation hole 181a.
[63] If the engine 210 of the weeder 200 is driven at this phase, the rotational force is transmitted to the input bevel gear 12 through the rotation bar 222, and the connected output bevel gear 171 rotates. The driving rotating body 120 which is coupled with the output bevel gear 171 moves together with the output bevel gear 171.
[64] If the driving rotating body 120 rotates, the endless chain belt 140 rotates as shown in
FIG. 4. The connecting member 150 which is coupled with the endless chain belt 140 performs a linear movement in a linear area of the endless chain belt 140 and rotational movement in a curved area by being placed in the center of the radius of curvature of the endless chain belt 140. Thus, the saw blade 160 which is connected with the projection 151 of the connecting member 150 moves back and forth to perform a cutting operation. That is, the projection 151 performs a translational motion along a virtual line from the central shaft of the driving rotating body 120 to the central shaft of the idle rotating body 130 to reciprocate the saw blade 160.
[65] The saw blade 160 is supported and guided by the first and second lateral guide rollers 192a and 192b from both lateral sides while moving back and forth. Thus, the saw blade 160 does not shake. Also, the upper part of the saw blade 160 is supported and guided by the first and second upper guide rollers 193a and 193b not to shake up and down.
[66] A portable saw according to the presentinverition can be compatibly used by being connected i to various -devices even-without an additional driving means such as a motor, reduces size ana a-saw ' blade with an.endless chain belt and a pair of rotating bodies f©r J p6rfability and easy use and is manufacturcd-with af ¬ fordable costs.
[67] Particular Y, as the portable saw accordingitoΛheφresent invention is easily mounted in a feeder removing' weeds, itican.cut'.timber-as well as ^ remoying weeds^even without an additioπalrpowef saw.
[68] Although a few exemplary embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.