JP5166071B2 - Caster locking mechanism and folding table - Google Patents

Description

  The present invention is suitable for, for example, a folding mechanism for a caster of a folding table, reduces the number of parts and simplifies the configuration, and operates the caster locking mechanism in conjunction with the folding operation of the top plate. The present invention relates to a lock mechanism for a caster and a folding table, which can realize a reliable and quick operation of the locking mechanism and can ensure safety in use of the folding table.

  For example, a caster is attached to the lower part of the movable folding table or chair leg, and a lock mechanism having a braking function is provided on the caster to restrain movement of the folding table or chair when used. To ensure safety in use.

  Among these, as a locking mechanism for the folding table caster, a caster shaft fixed to an attachment such as a folding table and a pair of left and right wheels on both sides of the caster shaft are pivotally attached to the caster shaft. A support yoke for rotatably mounting, an operating shaft that is slidably mounted vertically through the caster shaft, and linked to the unfolding operation of the top plate via a link member or wire, and an operating shaft A pivot lock portion attached to the lower end of the wheel, a sawtooth brake lock receiving portion formed on the inner surface of the wheel, and pivotally attached to the support yoke, and engages the brake lock receiving portion to restrain the rotation of the wheel. Some include a lock piece having a turning lock receiving portion and a spring for urging the lock piece in the unlocking direction.

  The lock mechanism of the caster operates the link member and the wire in conjunction with the unfolding operation of the top plate, and moves the operating shaft to the link member and displaces the lock piece against the elasticity of the spring. The lock receiving portion is engaged with the brake lock receiving portion to restrain the rotation of the wheel, and the engagement between the turning lock receiving portion and the brake lock receiving portion is released by the elasticity of the spring, so that the wheel can be rotated ( For example, see Patent Document 1).

  However, this caster has a large number of parts and the structure becomes complicated and expensive, and the lock mechanism of the caster connects one end of a link member or wire to a hole formed in the upper end portion of the operating shaft, Since the other end is linked to the unfolding operation of the top plate, it is necessary to bend the link member or wire around the operating shaft due to the structure of the folding table. There is a problem that the moving range is widened and comes into contact with an adjacent member, so that the displacement of the top plate cannot be reliably and smoothly transmitted to the link member or the wire.

  Further, as another lock mechanism of the caster, a pair of wheels are arranged on the left and right in a frame pivotably attached to the lower part of the support shaft, and disc-shaped engagement teeth are provided inside the wheels, An operation pin is attached to the inside of the support shaft so as to be movable up and down, and the operation pin is urged so as to be movable upward. The body is fixed, the upper end of the operation pin is arranged to be engageable with the cam body, the engagement gear is fixed to the lower part of the support shaft, and the braking arm can be rotated inside the frame The brake arm is linked to the lower end of the operating pin, and the support arm brake body is provided on the brake arm so as to be rotatable coaxially. The support arm brake body is engaged with the engaging gear. There is one in which a wheel braking body that is detachably disposed and attached to a braking arm is detachably disposed on the engagement gear.

  The lock mechanism of the caster rotates the operation lever, moves the cam body to the operation lever, pushes down the operation pin, engages an adjustment bolt with the operation pin, and engages the support shaft braking body with the engagement lever. The wheel engages with the combined gear to brake the turning of the frame, and the engagement end of the wheel brake member is engaged with the engagement gear to brake the rotation of the wheel (for example, see Patent Document 2). ).

  However, this caster has a large number of parts and is complicated and expensive, and the lock mechanism of the caster rotates and restores the wheel by rotating the operation lever, which is unnatural. There was a problem that the operation lever was forced to operate in a posture.

  As another caster locking mechanism, a single operation lever is provided on the lower surface of the table top plate, one end of the wire is connected to the operation lever, and the other end is provided at the lower end of the leg. In addition, there is one in which the four casters are locked and unlocked by locking and unlocking the operation lever in association with a lock device of four casters (see, for example, Patent Document 3).

  However, the lock device of the caster has a large number of parts, has a complicated structure and is expensive, and the lock mechanism requires an operation lever operation separately from the folding operation of the top plate. There is a problem that the operation is troublesome and the operation of the operation lever is often forgotten, and the safety when the table is used is impaired.

Japanese Patent No. 3190919 Japanese Patent No. 3252266 JP 2007-131239 A

  The present invention solves such a problem, and is suitable for, for example, a lock mechanism of a caster of a folding table, reduces the number of parts, simplifies the configuration, and cooperates with the folding operation of the top plate. It is an object of the present invention to provide a caster lock mechanism and a folding table that can operate the lock mechanism of the caster, realize a reliable and prompt operation of the lock mechanism, and ensure safety in use of the folding table. To do.

According to the first aspect of the present invention, there is provided a caster shaft that can be fixed to the lower end portion of the leg column, a movable shaft that is slidably disposed inside the leg column , a slidably inserted into the caster shaft, and an upper A lock pin urged movably to the caster, a housing rotatably mounted on the caster shaft, a pair of wheels rotatably supported on the housing, and a plurality of engagement teeth provided inside the wheel a lock cam which is pivoted rotatably to the side surface of the wheel, one end arranged to be engaged with the lower end portion of the lock pin and having said engagement teeth and disengageable possible locking claw, leg support post caster comprising a movable member, the arranged rotatably on side of - of the locking mechanism, telescopic displaceably disposed an upper end of the movable shaft to the top of the leg post, movable upper portion of the movable shaft It is connected to one side of the member so as to be able to rotate, and is attached to the leg post. One end of the link strut is rotatably connected, the other end of the link strut is rotatably connected to the other side of the movable member, and a knock pin engageable with the lock pin is connected to the lower end of the movable shaft. The knock pin is provided so as to be interlocked with the displacement of the movable member, and the knock pin is spaced apart above the lock pin when the caster is unlocked, and can be engaged with the upper end of the lock pin when the caster is locked. The upper end of the movable shaft is connected to one side of the movable member, and the other side of the leg strut and the movable member is pivotally connected to both end portions of the link column, so that the rotational displacement of the movable member is used as the movable shaft. Compared to the conventional mechanism that transmits the displacement of the movable member via the wire cable and multiple links, the locking and unlocking operation of the caster is reliably and promptly performed. I can do it To solve the troublesome to perform the operation and the operation of the movable member separately, caster - locking and unlocking operation in conjunction with the displacement of the movable member is reliably and quickly performed so.
According to the invention of claim 2, an arc shaped leaf spring is integrally formed on the side surface of the housing, and one end portion of the leaf spring is disposed so as to be engageable with the inside of the one end portion of the lock cam, thereby reducing the number of parts. In addition to simplification, the caster can be reliably locked and unlocked.

According to a third aspect of the present invention, there is provided a lock pin that is slidably inserted into a caster shaft fixed to the lower end portion of the leg column and urged to move upward, and a movable pin that is movably disposed inside the leg column. A shaft, a housing rotatably mounted on the caster shaft, a pair of wheels rotatably supported on the housing, a plurality of engagement teeth provided on the inside of the wheels, and a side surface of the wheel. rotatably the pivotally mounted, it can engage to place the one end to the lower end of the lock pin and the lock cam having the engaging teeth and disengageable possible locking claw, pivotable upper side of the leg support post In the folding table provided with the top plate, the upper end portion of the movable shaft is provided to be extendable and displaceable above the leg column, and the upper end portion of the movable shaft can be rotated to one side of the top plate. And one end of the link strut is pivotably connected to the leg strut, The other end of the link support is connected to the other side of the top plate so as to be rotatable, and a knock pin that can be engaged with the lock pin is connected to the lower end of the movable shaft, and the knock pin is provided so as to be interlocked with the displacement of the top plate. The knock pin is disposed so as to be spaced above the lock pin when the caster is unlocked, and can be engaged with the upper end of the lock pin when the caster is locked. The upper end of the movable shaft is located on one side of the top plate. And the other side of the leg column and the top plate are connected to both ends of the link column, and the rotational displacement of the top plate is transmitted to the movable shaft, which is reliably transmitted to the lock pin via the knock pin. Compared with the conventional mechanism that transmits the displacement of the top plate via a bull or multiple links, the caster can be locked and unlocked reliably and quickly, and the trouble of performing separate operation and operation of the top plate is eliminated. And casters Click and unlock operates in conjunction with the displacement of the top plate are reliably and quickly perform so.
According to a fourth aspect of the present invention , an arc shaped leaf spring is integrally formed on the side surface of the housing, and one end portion of the leaf spring is disposed so as to be engageable with the inside of the one end portion of the lock cam to reduce the number of parts. In addition to simplification, the caster can be reliably locked and unlocked .

According to the first aspect of the present invention, the upper end portion of the movable shaft is provided so as to be extendable and displaceable above the leg column, and the upper end portion of the movable shaft is rotatably connected to one side of the movable member and is linked to the leg column. One end of the support column is rotatably connected, the other end of the link support member is rotatably connected to the other side of the movable member, a knock pin engageable with the lock pin is connected to the lower end of the movable shaft, The knock pin is provided so that it can be interlocked with the displacement of the movable member, and the knock pin is spaced apart above the lock pin when the caster is unlocked, and can be engaged with the upper end of the lock pin when the caster is locked. Therefore, the upper end of the movable shaft is connected to one side of the movable member, and the other side of the leg column and the movable member is rotatably connected to both ends of the link column, so that the rotational displacement of the movable member can be used as the movable shaft. Communicate this to the lock pin securely via the knock pin. Compared to the conventional mechanism that transmits the displacement of the movable member via a wire cable or a plurality of links, the caster can be locked and unlocked reliably and quickly, and the movable member is operated and operated separately. Troublesomeness can be eliminated and the caster can be locked and unlocked reliably and promptly in conjunction with the displacement of the movable member .
According to the second aspect of the present invention , an arc shaped leaf spring is integrally formed on the side surface of the housing, and one end portion of the leaf spring is disposed so as to be engageable with the inside of the one end portion of the lock cam. The caster can be locked and unlocked reliably.

According to the invention of claim 3, the upper end portion of the movable shaft is provided so as to be able to expand and contract above the leg column,
The upper end is pivotally connected to one side of the top plate, and one end of the link post is rotated to the leg post.
The other end of the link column is pivotally connected to the other side of the top plate, and
A knock pin that can be engaged with the lock pin is connected to the end portion, the knock pin is provided so as to be interlocked with the displacement of the top plate, and the knock pin is arranged spaced above the lock pin when the caster is unlocked. Since the upper end of the lock pin is engageable with the upper end of the lock pin at the time of locking, the upper end of the movable shaft is connected to one side of the top plate, and the other side of the leg column and the top plate is connected to both ends of the link column. A conventional mechanism that enables the top plate to be pivotally displaced, transmits the top plate's rotational displacement to the movable shaft, reliably transmits it to the lock pin via the knock pin, and transmits it via a wire cable or multiple links. Compared to the above, the caster can be locked and unlocked reliably and quickly, and the trouble of separately performing the operation and operation of the top plate is eliminated. It can be carried out in dynamic.
In the invention of claim 4, an arc shaped leaf spring is integrally formed on the side surface of the housing, and one end portion of the leaf spring is disposed so as to be engageable with the inside of the one end portion of the lock cam. strive to simplicity of caster - locking and unlocking operation can be Nau reliably rows.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A description will now be given of an illustrated embodiment in which the present invention is applied to a caster attached to the lower end of a leg of a folding table. In FIGS. 1 to 9, reference numeral 1 denotes a horizontally long rectangular top plate which is a movable member. The pivots 2 and 3 are arranged in parallel at the front and rear positions, and both sides and intermediate positions of the pivots 2 and 3 are rotatably supported via brackets 4 and 5.
The brackets 4 and 5 have two triangular holders formed by bending a steel plate into a substantially triangular shape, the upper side thereof is screwed to the top plate 1, and the pivots 2 and 3 are attached to the hollow portion of the triangular holder. It is inserted so that it can rotate.

The upper end of the link column 6 is connected to both ends of the pivot 2, and the lower end of the link column 6 is rotatably connected to a later-described reinforcing frame constructed between the left and right leg columns 7, 7.
The leg support 7 is disposed obliquely downward from the rear of the top plate 1 to the front, and a caster of the present invention, which will be described later, is attached to the lower end thereof.
Further, the upper end portion of the slide column 8 which is a movable shaft is connected to both ends of the pivot shaft 3, the slide column 8 is slidably inserted into the leg column 7, and a knock pin which will be described later is attached to the lower end portion. It has been.

In the figure, 9 is the above-mentioned reinforcing frame constructed between the lower portions of the left and right leg columns 7 and 7, and 10 is a curtain attached between the left and right link columns 6 and 6, and the upper end portion is held by the binding band 11. .
12 is a rubber plate, 13 is a handle for holding the top plate, 14 is a shelf network, and 15 is a contact plate attached to the lower back surface of the leg column 7.

  A joint 7a protrudes outward from the upper part of the leg struts 7, 7. The upper end of the rear leg struts 16, 16 is fixed to the joint 7a, and the lower end of the joint is extended obliquely downward to the rear. Conventional casters 17 and 17 are attached to the lower end.

The casters 18 and 18 according to the present invention are attached to the lower ends of the leg struts 7 and 7 so that the casters 17 and 18 can travel on the floor surface 19.
In the embodiment, the caster 18 on the front side has a lockable locking mechanism, and the caster 17 on the rear side has no locking mechanism.

The slide column 8 is formed of a tube body that can be inserted into the leg column 7, and a knock pin 20 made of synthetic resin such as nylon (registered trademark) is inserted into a lower end portion thereof.
A substantially inverted U-shaped cut groove 21 is formed at a position opposed to the upper tubular peripheral surface of the knock pin 20, and a tongue-like locking piece 22 is cut out by the cut groove 21.

A locking projection 23 projects from the tip of the locking piece 22, engages the locking projection 23 with a through hole 64 formed in the lower portion of the slide column 8, and attaches the knock pin 20 to the slide column 8. ing. In the figure, 28 is a flange projecting annularly on the intermediate peripheral surface of the knock pin 20.
A lower half portion of the knock pin 20 is formed in a substantially semicircular cross section, and an oblique engagement surface 20a is formed at a lower end portion thereof, and the engagement surface 20a is arranged to be engageable with a head portion 24a of the lock pin 24. Has been.

  When the top plate 1 is folded, the knock pin 20 is spaced above the head 24a as shown in FIG. 6, and moves downward as shown in FIG. 7 when the top plate 1 is unfolded, that is, in use. The head 24a is engageable.

A shaft portion 25a of a connecting piece 25 made of synthetic resin is inserted into the lower end portion of the leg column 7, and a screw 26 is screwed into the shaft portion 25a. A concave hole 27 into which the knock pin 20 can be inserted is formed in the upper portion of the shaft portion 25a, and a screw hole 29 is formed in the bottom portion of the concave hole 27.
A bolt 31, which is a caster shaft, incorporated in the housing 30 of the caster 18 is screwed into the screw hole 29, a nut 32 is screwed into the upper portion of the bolt 31, and a connecting piece 25 is placed on the nut 32. The lower end is placed.

Lower half of the bolt 31 is inserted rotatably in the through hole 33 of the barrel portion to be described later erected in the housing 30, Ru Tei fitted with snap ring 34 at its lower end.
A through hole 35 is formed in the bolt 31, the lock pin 24 is inserted into the through hole 35 so as to be movable up and down, and a lower end portion thereof is disposed so as to be engageable with a locking piece 37 of one lock cam 36. ing. In this case, it is desirable to provide a recess capable of accommodating the lower end of the lock pin 24 in the locking piece 37 to prevent slipping when the lock pin 24 is engaged.

  The caster 18 is configured in a double wheel type as shown in FIGS. 8 and 9, the housing 30 forming the skeleton thereof, the lock cams 36 and 38 that are movably attached to both sides of the housing 30, and the housing 30. The wheels 40 and 41 are rotatably mounted on both sides of the wheel 40 via axles 39, and the wheel covers 42 and 43 are mounted on the outside of the wheels 40 and 41.

Among these, the housing 30 is formed in a substantially semicircular shape by a synthetic resin such as nylon (registered trademark), and a plate-like stage 44 is integrally formed on the outer periphery thereof.
A shaft tube portion 45 having the through-hole 33 is formed on one side of the housing 30, and a ground paper-shaped through-hole 47 is formed on the side wall 46, and is biased toward the through-hole 47. An arcuate leaf spring 48 as a means is integrally formed.

In the figure, 55 is a boss formed at the center of the housing 30, and 56 is a shaft hole formed in the boss 55 so that the axle 39 can be inserted.
One end of the leaf spring 48 is integrally formed with the side wall 46 and the other end portion is disposed inside the through hole 47 so as to be engageable with lock cams 36 and 38 disposed outside the leaf spring 48. Yes.

The side surfaces of the lock cams 36 and 38 are formed in a substantially C shape by the above-described synthetic resin, and a pin 50 is fitted in a pin hole 49 in the middle portion thereof, and is connected to the side wall 46 so as to be rotatable and movable. In addition, locking claws 51 and 52 that can be engaged with engagement teeth described later are provided on one end of the lock cams 36 and 38, and the one of the lock cams 36 and 38 has a deformed fit on the side of the intermediate portion thereof. A mating groove 53 is formed, and the fitting portion 38a of the other lock cam 38 is press-fitted into the fitting groove 53. In the figure, reference numeral 57 denotes a bead-shaped convex portion protruding from the inner surface of the fitting portion 38a. It is.

When the top plate 1 is folded, the locking cams 36 and 38 are released from the pressing of the lock pin 24 to maintain the original position, and the braking or locking operation of the wheels 40 and 41 can be prevented. Yes.
On the other hand, when the expansion top plate 1, i.e. during use, the engaging piece 37 is pressed against the lock pin 24, and rotates around the pin hole 49 against the resilience of the plate spring 48, the locking claw The wheels 51 and 52 are engaged with engaging teeth, which will be described later, so that the wheels 40 and 41 can be braked or locked.

The wheels 40 and 41 are formed in substantially the same disk shape by the above-described synthetic resin, and a plurality of engagement teeth 58 are annularly arranged inside thereof, and the adjacent engagement teeth 58 and 58 are arranged. The locking claws 51 and 52 are disposed so as to be able to engage with each other.
In this case, instead of providing the engagement teeth 58 on the center side of the wheels 40 and 41 as in the embodiment, the engagement teeth 58 may be provided on the inner surface of the outer peripheral portion. 38 protrudes outside the lower peripheral surface.

In the figure, 59 is a concave hole formed in the center of the engaging tooth 58, and the boss 55 can be inserted therein. A shaft hole 60 into which the axle 39 can be inserted is formed in the center of the bottom of the concave hole 59.
The wheel covers -42 and 43 are provided with annular ribs 61 projecting from the inner peripheral edge thereof so that the ribs 61 can be fitted into annular grooves 62 formed outside the wheels 40 and 41.
In addition, 63 is an annular groove formed at both ends of the axle 39, and a retaining ring (not shown) is attached to the groove 63.

  The caster locking mechanism configured as described above releases the lower end of the lock pin 24, attaches no other parts as in the prior art, forms the leaf spring 48 integrally with the housing 30, and further locks the cams 36, 38. A single locking claw 51, 52 is formed on one side, and a flat locking piece 37 is formed on one side thereof. Therefore, a cylindrical member is attached to the lock pin 24, and a leaf spring is provided separately from the housing. Compared to a conventional double-wheel caster in which a plurality of locking claws are provided on the lock cam and the locking piece at one end requires complicated processing, the number of parts is reduced, and the configuration of the lock pin 24 and the lock cams 36 and 38 is simplified. Therefore, this can be manufactured easily and inexpensively.

When the lock cams 36 and 38 are assembled to the housing 30, the lock cam 36 is positioned on one side of the side wall 46, and the fitting portion 38 a of the lock cam 38 is press-fitted into the fitting groove 53 protruding to the other side of the side wall 46. The lock cams 36 and 38 are disposed with the pin 50 interposed therebetween, and the pins 50 are inserted into the pin holes 49 to connect the lock cams 36 and 38.
By integrally connecting the lock cams 36 and 38 as described above, compared to the case where the lock cams 36 and 38 having a two-part configuration are connected with the side wall 46 interposed therebetween, their synchronous operation can be achieved, and the operation of the lock cams 36 and 38 can be improved. Certainty and stability can be achieved.

  On the other hand, the lock mechanism of the caster 18 connects the knock pin 20 that engages with the head 24 a of the lock pin 24 to the slide column 8, and the upper end of the column 8 is arranged on the lower surface of the top plate 1. Since the caster 18 is directly locked or unlocked by the operation of the top plate 1 in conjunction with the folding operation and the unfolding operation of the plate 1, these operations can be performed automatically and quickly, and these operations can be performed in the conventional manner. There is no hassle to perform separately from the operation of the plate 1, and the table can be used safely.

Next, when assembling the caster 18, the bolt 31 is inserted into the through hole 33 of the shaft tube portion 45 of the housing 30, the retaining ring 34 is attached to the lower end thereof, and the nut 32 is screwed into the upper screw shaft. A bolt 31 is attached to the housing 30.
Thereafter, the lock cams 36 and 38 are disposed on both sides of the side wall 46 of the housing 30, the pins 50 are inserted into these pin holes 49, and the other lock cam 38 is fitted into the fitting groove 53 of one lock cam 36. The lock cams 36 and 38 are connected by press-fitting the portion 38a.
It protrudes outside the lower peripheral surface.

Thereafter, the wheels 40 and 41 are arranged on both sides of the housing 30 with the engagement teeth 58 and 58 facing inward, the inner concave hole 59 is fitted into the boss 55, and the engagement teeth 58 and 58 are connected to the lock cam 36. , 38 inside.
Then, the axle 39 is inserted into the shaft holes 60, 60, retaining rings (not shown) are attached to the annular grooves 63 on both sides, the wheels 40, 41 are attached to both sides of the housing 30, and then outside the wheels 40, 41. The wheel covers 42 and 43 are attached via the ribs 61.

  As described above, the caster 18 is assembled by releasing the lower end portion of the lock pin 24, forming the leaf spring 48 integrally with the housing 30, and forming the single locking claws 51, 52 on the lock cams 36, 38. Since the flat locking piece 37 is formed at one end thereof, the number of parts is reduced and the assembly of the lock pin 24 and the lock cams 36 and 38 is facilitated as compared with a conventional double wheel caster.

  When the lock mechanism is linked to the caster 18 assembled in this way, the lock pin 24 is inserted into the through hole 35 of the bolt 31, and the screw shaft of the bolt 31 is screwed into the screw hole 29 in the connecting piece 25. The shaft portion 25a of the piece 25 is inserted into the lower end portion of the leg column 7, and screws 26 are screwed into these to be connected.

On the other hand, before assembling the slide column 8 to the leg column 7, the upper shaft portion of the knock pin 20 is inserted into the lower end portion of the slide column 8, and the locking projections 23, 23 are formed through holes 64 formed in the lower portion of the slide column 8. , 64 and the knock pin 20 is latched.
In addition, casters 17 and 17 having no conventional locking mechanism are attached to the lower ends of the rear leg columns 16 and 16.

  When the top plate 1 of the folding table assembled in this way is folded, the link support 6 rotates backward about a pivot (not shown) at the lower end, and the top 1 stands up and pivots about the pivot 2. Then, the pivot 3 on the rear side moves above the leg column 7, the slide column 8 is pulled up above the leg column 7, and the top plate 1 is superimposed on the leg column 7 and the slide column 8 and folded. This situation is as shown in FIG.

For this reason, the slide column 8 is moved upward, the knock pin 20 at the lower end thereof is moved together and separated from the connection piece 25, and the engagement of the lock pin 24 with the head 24a is released.
As a result, the lock cams 36 and 38 return and rotate about the pin 50 due to the elasticity of the leaf spring 48, the locking claws 51 and 52 move outward in the radial direction and are separated from the engagement teeth 58, and the wheels 40 and 41. On the other hand, the locking piece 37 moves to the original position and pushes up the lower end of the lock pin 24.

  This situation is as shown in FIG. 6, and the locking claws 51 and 52 are separated from the engagement teeth 58 and their engagement is released so that the caster 18 can run. As shown in FIG. 4, it is possible to obtain a stacking state in which two tables are in close contact with each other and stored.

When using the table by unfolding the top plate 1 from the folded state of the top plate 1, the table is moved to a predetermined position, and the front end portion of the top plate 1 is held and pushed up.
In this way, the link column 6 is erected forward about a pivotal support (not shown) at the lower end, the front end of the top plate 1 is pulled by the pivot 2, and the rear end is forward. It is pulled down to move down and moves from a tilted posture to a horizontal state.

By such operation of the top plate 1, the slide support 8 is pushed down via the pivot 3, and the knock pin 20 at the lower end of the support 8 comes into contact with the head 24 a of the lock pin 24 to push down the lock pin 24.
For this reason, the lower end portion of the lock pin 24 pushes down the locking piece 37 of the lock cam 36, and the lock cam 36 and the lock cam 38 on the other side rotate around the pin 50 against the elasticity of the leaf spring 48. The locking claws 51 and 52 move in the radial direction and engage with the engaging teeth 58 and 58 on both sides.
As a result, the rotation of the wheels 40 and 41 integral with the engagement teeth 58 and 58 is prevented and locked. This situation is as shown in FIG.

  When the top plate 1 is set horizontally and the use state as shown in FIG. 3 is formed, the engagement state between the knock pin 20 and the lock pin 24 is maintained, and the lock state of the wheels 40 and 41 is maintained. A safe use state of the table is formed.

Thus, according to the present invention, the wheels 40 and 41 can be automatically locked when using the table for setting the top plate 1 horizontally, so that the lock lever provided separately from the top plate or the top plate as in the prior art. And the operation of the lock lever is performed separately from the level setting operation of the top plate, so that the lock operation is not forgotten, and the lock state can be easily and surely executed. Since the support column 8 is a rigid body and is coaxially arranged, and the upper end portion of the slide support column 8 is connected to the pivot 3, the displacement of the top plate 1 can be directly and directly compared to the case of connecting a wire or a plurality of links. It can be transmitted without loss and a certain locked state can be obtained.

  In this embodiment, the knock pin 20 and the slide column 8 are refracted at a certain angle with respect to the lock pin 24. However, it is also possible to arrange them coaxially. , The displacement required for the locking operation is transmitted directly and without loss to the lock pin 24, and the caster provided at the lower end of a vertical footnote such as a conference table or the caster lock mechanism provided on the leg of the chair. Can respond.

  As described above, the caster lock mechanism and the folding table according to the present invention reduce the number of parts and simplify the configuration, and operate the caster lock mechanism in conjunction with the folding operation of the top plate to lock the caster. Since the mechanism can be surely and promptly operated and the safety in use of the folding table can be ensured, it is suitable, for example, for a locking mechanism of a folding table caster.

It is a front view of the folding table for meetings to which the present invention is applied. In the plan view of FIG. 1, the top plate is omitted from one side. FIG. 1 is a right side view of the table with the top plate unfolded. It is a side view which shows the stacking condition at the time of folding of the top plate of the folding table for meetings to which this invention is applied.

It is a side view which expands and shows the principal part of the caster to which this invention is applied. The principal part of the caster to which this invention is applied is expanded and sectional drawing, The unlocked state of the caster is shown. The principal part of the caster to which this invention is applied is expanded and sectional drawing, The locked state of the caster is shown. It is a perspective view which expands and shows the caster to which this invention is applied. It is a perspective view which decomposes | disassembles and shows the principal part of the caster to which this invention is applied.

Explanation of symbols

1 Movable member (top plate)
7 Attachment (leg post)
8 Movable shaft (slide support)
17, 18 Casters

20 dowel pin 24 lock pin 24a head 30 housing 31 caster shaft (bolt)

36, 38 Lock cam 40, 41 Wheel 48 Biasing means (leaf spring)
51, 52 Locking claw 53 Fitting groove 58 Engaging tooth

Claims (4)

A caster shaft that can be fixed to the lower end of the leg strut, a movable shaft that is movably disposed inside the leg strut, and is slidably inserted into the caster shaft and urged so as to be movable upward. A lock pin, a housing rotatably mounted on the caster shaft, a pair of wheels rotatably supported on the housing, a plurality of engagement teeth provided inside the wheels, and a side surface of the wheel. rotatably the pivotally mounted, it can engage to place the one end to the lower end of the lock pin and the lock cam having the engaging teeth and disengageable possible locking claw, pivotable upper side of the leg support post In the caster lock mechanism provided with the movable member, the upper end of the movable shaft is provided so as to be able to expand and contract above the leg column, and the upper end of the movable shaft is rotated to one side of the movable member. And connect one end of the link strut to the leg strut. The other end of the link strut is rotatably connected to the other side of the movable member, a knock pin engageable with the lock pin is connected to the lower end of the movable shaft, and the knock pin is connected to the movable member. The knock pin is provided so as to be interlocked with the displacement, and is arranged so as to be spaced above the lock pin when the caster is unlocked, and is capable of being engaged with the upper end of the lock pin when the caster is locked. Caster lock mechanism. 2. The caster lock mechanism according to claim 1 , wherein an arc-shaped plate spring is integrally formed on a side surface of the housing, and one end portion of the plate spring is disposed to be engageable with an inner side of one end portion of the lock cam . A lock pin that is slidably inserted into a caster shaft fixed to the lower end of the leg column and urged so as to move upward; a movable shaft that is movably disposed inside the leg column; and the caster shaft A pivotally mounted housing, a pair of wheels rotatably supported on the housing, a plurality of engagement teeth provided on the inside of the wheels, and pivotally attached to a side surface of the wheels, A lock cam having one end engageable with a lower end of the lock pin and having a locking claw capable of engaging with and disengaging from the engaging tooth; and a top plate rotatably disposed above the leg post. In the folding table provided, the upper end portion of the movable shaft is provided so as to be extendable and displaceable above the leg column, and the upper end portion of the movable shaft is rotatably connected to one side of the top plate, and the leg column. One end of the link post is rotatably connected to the other end of the link post. The other side of the top plate is pivotally connected, the lower end of the movable shaft is connected to a knock pin engageable with the lock pin, the knock pin is provided so as to be interlocked with the displacement of the top plate, and the knock pin is connected to a caster. A folding table which is provided spaced apart above the lock pin when unlocked and is provided so as to be engageable with the upper end of the lock pin when the caster is locked . 4. The folding table according to claim 3 , wherein an arc-shaped plate spring is integrally formed on a side surface of the housing, and one end portion of the plate spring is disposed so as to be engageable with the inside of one end portion of the lock cam .

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