Wood planing machine provided with a cutter locking device

A wood planing machine includes a machine base having first and second mounting sides. First and second pairs of posts are fixed on the machine base at the first and second mounting sides, respectively. A cutter carriage is disposed above the machine base, and has opposite end portions mounted respectively, vertically and movably on the posts. A cutter unit has first and second shaft portions journalled to the first and second end portions of the cutter carriage. The second shaft portion is formed with a first engagement section. A cutter locking device includes a locking plate mounted movably on the second end portion of the cutter carriage, and having a vertical plate portion disposed adjacent to the second shaft portion, and a horizontal plate portion disposed below the second shaft portion and formed with a second engagement section. A biasing unit biases the locking plate to move upwardly on the second end portion of the cutter carriage to an upper position to engage the first and second engagement sections, thereby preventing rotation of the cutter unit relative to the carriage. The locking plate is movable forcibly to a lower position to disengage the first and second engagement sections from each other.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The invention relates to a wood planing machine, more particularly to a
 wood planing machine provided with a cutter locking device for locking a
 cutter unit when the cutter unit is at a non-operative state.
 2. Description of the Related Art
 Referring to FIG. 1, a conventional wood planing machine is shown to
 include an elongated machine base 10, first and second pairs of posts 100,
 a cutter carriage 11, vertical first and second threaded rods (not
 visible), carriage fastening means, an elongated cutter unit 12, and a
 cutter locking device 17.
 As illustrated, the machine base 10 has opposed first and second mounting
 sides spaced apart from each other in a longitudinal direction, and
 opposed feed-in and take-out sides spaced apart from each other in a
 transverse direction. The first and second pairs of posts 100 are fixed on
 the machine base 10 at the first and second mounting sides, respectively.
 The cutter carriage 11 is disposed above the machine base 10, and has first
 and second end portions 110 mounted respectively, vertically and movably
 on the first and second pairs of posts 100 for moving the cutter carriage
 11 along the posts 100, thereby adjusting height of the cutter carriage 11
 relative to the machine base 10.
 The carriage fastening means fastens releasably the carriage 11 on the
 first and second pairs of posts 100 after adjusting the height of the
 carriage 11 relative to the machine base 10.
 The cutter unit 12 is disposed to extend in the longitudinal direction, and
 has first and second shaft portions 120 journalled to the first and second
 end portions 110 of the cutter carriage 11.
 The cutter locking device includes an inverted L-shaped locking member 17
 mounted pivotally on an outer surface of the second end portion 110 of the
 cutter carriage 11 above the second shaft portion 120 via a pivot pin 171,
 a pair of engagement grooves 121 formed in an outer surface of the second
 shaft portion 120 in a radial direction, and a biasing unit 18 which
 biases a first arm portion 172 of the locking member 17 to rotate about
 the pin 171 in a direction in such a manner that an engaging tongue 173 of
 a second arm portion 174 engages one of the engagement grooves 121 in the
 cutter unit 12, thereby preventing rotation of the cutter unit 12 relative
 to the carriage 11 and disposing the cutter unit 12 at a locked position.
 The cutter carriage 11 further includes a waste passage 15 formed in an
 outer surface of the second end portion 110 thereof at an elevation above
 the second shaft portion 120, and a waste collection member 16 which is
 inserted removably into the waste passage 15 for guiding waste that
 results from operation of the cutter unit 12 and which presses the first
 arm portion 172 of the locking member 17 against biasing action of the
 biasing unit 18, thereby removing the engaging tongue 173 from the
 engagement groove 121 and correspondingly permitting rotation of the
 cutter unit 12 relative to the cutter carriage 11, and disposing the
 cutter unit 12 at an unlocked position.
 One disadvantage that results from the use of the aforesaid conventional
 wood planing machine resides in that the locking member 17 is mounted
 pivotally on the carriage 11, thereby affecting adversely the locking
 effect thereof.
 SUMMARY OF THE INVENTION
 Therefore, the object of this invention is to provide a wood planing
 machine which is provided with a cutter locking device which is clear of
 the aforementioned drawback that results from the use of the conventional
 wood planing machine.
 Accordingly, the wood planing machine of the present invention includes an
 elongated machine base, first and second pairs of posts, a cutter
 carriage, carriage fastening means, an elongated cutter unit, and a cutter
 locking device. The machine base has a top surface, opposed first and
 second mounting sides spaced apart from each other in a longitudinal
 direction, and opposed feed-in and take-out long sides spaced apart from
 each other in a transverse direction. The first and second pairs of posts
 are fixed on the top surface of the machine base at the first and second
 mounting sides, respectively. The cutter carriage is disposed above the
 machine base, and has first and second end portions mounted respectively,
 vertically and movably on the first and second pairs of posts for moving
 the cutter carriage along the posts, thereby adjusting height of the
 cutter carriage relative to the machine base. The carriage fastening means
 fastens releasably the carriage on the first and second pairs of posts
 after adjusting the height of the carriage relative to the machine base.
 The cutter unit is disposed to extend in the longitudinal direction, and
 has first and second shaft portions journalled to the first and second end
 portions of the cutter carriage. The second shaft portion is formed with a
 first engagement section. The cutter locking device includes a locking
 plate and a biasing unit. The locking plate is mounted movably and
 vertically on an outer surface of the second end portion of the cutter
 carriage, and has a vertical plate portion disposed adjacent to the second
 shaft portion, and a horizontal plate portion which extends integrally,
 laterally and outwardly from a lower end of the vertical plate portion so
 as to be disposed below the second shaft portion and which is formed with
 a second engagement section. The biasing unit biases the locking plate to
 move upwardly on the outer surface of the second end portion of the cutter
 carriage to an upper position to engage the first and second engagement
 sections, thereby preventing rotation of the cutter unit relative to the
 carriage. The locking plate is movable forcibly against biasing action of
 the biasing unit to a lower position so as to disengage the first and
 second engagement sections from each other, thereby permitting rotation of
 the cutter unit relative to the carriage.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
 Referring to FIGS. 2 and 3, the preferred embodiment of a wood planing
 machine of this invention is shown to include an elongated machine base
 20, first and second pairs of posts 26, a cutter carriage 21, carriage
 fastening means 23, an elongated cutter unit 22, and a cutter locking
 device 30.
 As illustrated, the machine base 20 has opposed first and second mounting
 sides 201 spaced apart from each other in a longitudinal direction, and
 opposed feed-in and take-out long sides spaced apart from each other in a
 transverse direction.
 The first and second pairs of posts 26 are fixed on the top surface of the
 machine base 20 at the first and second mounting sides 201, respectively.
 The cutter carriage 21 is disposed above the machine base 20, and has first
 and second end portions 210 mounted respectively, vertically and movably
 on the first and second pairs ofposts26 for moving the cutter carriage 21
 along the posts 26, thereby adjusting height of the cutter carriage 21
 relative to the machine base 20.
 The carriage fastening means 23 is provided on the cutter carriage 21, and
 is operably connected to the first and second pairs of posts 26 for
 fastening the carriage 21 to the posts 26 after height adjustment of the
 cutter carriage 21 by virtue of rotation of two threaded rods 27 which are
 mounted rotatably on the machine base 20 (see FIG. 3). Since the structure
 of the carriage fastening means 23 is not pertinent to the present
 invention, a detailed description thereof will be omitted herein for the
 sake of brevity.
 The cutter unit 22 is disposed to extend in the longitudinal direction, and
 has first and second shaft portions 220 journalled to the first and second
 end portions 210 of the cutter carriage 21 in such a manner that the
 second shaft portion 220 is exposed to the second end portion 210 of the
 cutter carriage 21. The second shaft portion 22 is formed with a first
 engagement section 221. Preferably, the first engagement section 221 of
 the cutter unit 22 is shaped as an axially extending projection that has
 two opposed vertical side surfaces.
 The cutter locking device 30 includes a locking plate 31, and a biasing
 unit 32. The locking plate 31 is mounted movably and vertically on an
 outer surface of the second end portion 210 of the cutter carriage 21, and
 has a vertical plate portion 314 which is disposed adjacent to the second
 shaft portion 220, and a horizontal plate portion 315 which extends
 integrally, laterally and outwardly from a lower end of the vertical plate
 portion 314 so as to be disposed below the second shaft portion 220 and
 which is formed with a second engagement section 312. The second
 engagement section 312 of the locking plate 31 is shaped as a notch that
 engages fittingly the projection of the cutter unit 22. The biasing unit
 32 biases the locking plate 31 to move upwardly on the outer surface of
 the second end portion 210 of the cutter carriage 21 to an upper position
 to engage the first and second engagement sections 221,312, thereby
 preventing rotation of the cutter unit 22 relative to the carriage 21. The
 locking plate 31 is movable forcibly against biasing action of the biasing
 unit 32 to a lower position so as to disengage the first and second
 engagement sections 221,312 from each other, thereby permitting rotation
 of the cutter unit 22 relative to the carriage 21.
 In the preferred embodiment, the carriage 21 further includes a waste
 passage 24 formed therein at an elevation above the second shaft portion
 220, and a waste collecting member 25 disposed removably in the waste
 passage 24 and adapted to collect waste resulting from operation of the
 cutter unit 22 when the locking plate 31 is at the upper position.
 The cutter locking device 30 further includes a plate-retention port 213
 formed in the outer surface of the second end portion 210 of the carriage
 21 above the second shaft portion 220 and in communication with the waste
 passage 24. The locking plate 31 further has a fixed insert element 311
 that extends perpendicularly from an upper end of the vertical plate
 portion 314 and into the plate-retention port 213 in the carriage 21 and
 that is capable of being pushed downwardly by the waste collecting member
 25 to the lower position, as shown in FIGS. 4 and 5. The waste collecting
 member 25 can be removed from the waste passage 24 when the cutter unit
 220 is not in operation. Under such a condition, the locking plate 31 is
 biased by virtue of the biasing unit 32 to the upper position, as best
 shown in FIGS. 6 and 7.
 The carriage 21 further includes a vertical plate-sliding slot 211 formed
 in the outer surface of the second end portion 210 of the carriage 21
 within which the vertical plate potion 314 of the locking plate 31 is
 slidably disposed, and a spring-mounting stub 36 fixed in a bottom surface
 of the sliding slot 211. The biasing unit 32 includes a compression spring
 which is disposed in the sliding slot 211 and which has a lower end that
 is fixed to the spring-mounting stub 36 and an upper end that is fixed to
 a horizontal protrusion 313 on the vertical plate portion 314 below the
 insert element 311 and that biases the locking plate 31 to the upper
 position. Preferably, a vertical plate cover 33 is mounted removably on
 the outer surface of the second end portion 210 of the carriage 21 by
 means of screws 34 which engage threaded holes 212 in the carriage 21 so
 as to conceal the sliding slot 211.
 With this invention thus explained, it is apparent that numerous
 modifications and variations can be made without departing from the scope
 and spirit of this invention. It is therefore intended that this invention
 be limited only as indicated in the appended claims.