JP2002137144A - Door lock device for machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a door lock device for a machine tool capable of opening a door from the interior of a splash cover even when a power source is brought into an OFF-state with a door closed. SOLUTION: A lock pin 30 engaged with a door 5 during closing of the door 5 and capable of fixing the door 5 and a spring 32 to energize the pin 30 in a door locking direction are situated at the outside of a splash cover 1. A solenoid actuator 36 is provided to move the pin 30 in a door unlocking direction against the elastic force of the spring 32 during operation thereof. An operation rod 42 to move the pin 32 in a door unlocking direction during non-operation of an actuator 36 is situated in a manner to extend through a cover 1 and move in its axial direction. A plunger 37 of the actuator 36 and the pin 30 are intercoupled through a rod 29 and a joint 38. Movement in an axial direction of a joint operation rod 42 is converted to movement in a door unlocking direction of the pin 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a door lock device for opening and closing an opening formed in a splash cover of a machine tool such as an NC lathe.

[0002]

2. Description of the Related Art As a door locking device for opening and closing an opening formed in a splash cover of a machine tool such as an NC lathe, the door is fixed outside the splash cover by engaging with the door when the door is closed. A lock member and a biasing means for biasing the lock member in the door lock direction are provided, and a direct-acting solenoid actuator for moving the lock member in the door lock release direction against the biasing force of the biasing means during operation is provided. Are known.

In such a door lock device, N
When the power of the C machine tool is turned on, the solenoid is excited and the solenoid actuator is activated, and the lock member is moved in the door unlocking direction, so that the door can be freely opened and closed in this state. After closing the door, pressing the start button to execute the machining program, the control device switches the solenoid to non-excitation, the solenoid actuator is deactivated, and the lock member is automatically activated by the biasing force of the biasing means. The door is engaged and urged in the door locking direction, thereby locking the door. After the machining is completed, that is, when the control device reads the end command code of the machining program, the solenoid is excited and the solenoid actuator is activated, and the lock member is moved in the door unlocking direction against the urging force of the urging means. As a result, the engagement of the lock member with the door is released, and the door lock is released.

[0004]

However, in a machine tool provided with the above-mentioned conventional door lock device, when the power is turned on, an operator opens the door to enter the splash cover, and Work may be done with the door closed. In this case, if the power of the machine tool is turned off during work due to an accident such as a power failure,
The solenoid is de-energized, the solenoid actuator is deactivated, and the lock member is automatically engaged with the door by the urging force of the urging means and urged in the door locking direction, and as a result, the door is locked. You. Therefore, there is a problem that the worker cannot open the door from inside the splash cover and is locked in the splash cover.

[0005] An object of the present invention is to solve the above-mentioned problem and to provide a door lock device for a machine tool that can open a door from inside a splash cover even when the power is turned off with the door closed. It is in.

[0006]

A door lock device for a machine tool according to the present invention is a door lock device for opening and closing an opening formed in a splash cover of a machine tool. A lock member which can be engaged with the door when the door is closed to lock the door, and a biasing means for biasing the lock member in the door locking direction are provided. In a door lock device provided with a solenoid actuator for moving a lock member in a door unlocking direction, an operation rod for moving the lock member in the door unlocking direction when the solenoid actuator is not operated passes through the splash cover and the axis thereof. The operation rod is provided between the operation rod and the lock member. Transmission means for converting the movement of the direction to the movement of the door unlocking direction of the locking member in which is disposed.

According to the door lock device of the present invention, when the worker enters the splash cover and is working with the door closed, the power of the machine tool is turned off and the lock member is pressed by the urging means. Is engaged with the door and urged in the door lock direction. As a result, when the door is locked, by moving the operation rod in the axial direction, the lock member is moved in the door unlock direction via the transmission means. Can be moved. Therefore, even when the power is turned off while the door is closed, the lock can be released from inside the splash cover and the door can be opened.

In the door lock device for a machine tool according to the present invention, the door is opened and closed by opening and closing drive means, and the opening and closing drive is performed by moving the operating rod when the lock member moves in the door unlocking direction. There may be provided a driving force releasing means for releasing the driving force of the means in the door closing direction. In this case, since the driving force of the opening / closing drive means in the door closing direction can be released by moving the operation rod in the door unlocking direction, the door can be quickly opened with a relatively small force.

For example, the opening / closing driving means is a direct-acting fluid actuator such as a pneumatic cylinder, and the driving force releasing means is provided around the operating rod, and the operating rod moves the lock member in the door unlocking direction. Is a valve that connects both pressure chambers of the fluid actuator to the atmosphere when it moves to.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the entire configuration of an NC lathe provided with a door lock device according to the present invention, and FIGS. 2 to 5 show the configuration of the door lock device. In the following description, FIG.
The upper and lower sides and the left and right sides are respectively referred to as the upper and lower sides and the left and right sides. The front side (the left side in FIG. 2) of FIG.

In FIG. 1, a splash cover (1) of an NC lathe has a left-side fixed cover (2) that covers the front and the upper.
An opening (4) extending from the front surface to the upper surface is formed between the right-side fixed cover portion (3), which is provided on the right side of the left-side fixed cover portion (2) at an interval and covers the front and upper sides. The opening (4) is opened and closed by an inverted L-shaped door (5) of a sliding door type. A headstock (6) is arranged inside the opening (4), and a tool rest (7) for holding a plurality of tools is arranged inside the left fixed cover part (2).

At the left end of the top wall portion (5a) of the door (5), a door
The horizontal engagement bar (8) is fixed so as to protrude leftward from (5). Notch (9) at upper left end of engaging bar (8)
Is formed, and a portion of the upper surface of the engagement bar (8) to the left of the notch (9) is an inclined surface (8a) inclined downward and leftward. In addition, the engagement bar
On the upper surface of the right end of (8), there is provided a dog (10) for operating a limit switch for detecting a closed end of a door (5) to be described later.

A pneumatic cylinder (11) (fluid actuator) for opening and closing the door (5) is provided on the top wall portion (3a) of the right fixed cover portion (3) of the splash cover (1).
However, it is mounted horizontally with the piston rod (11a) facing left. The tip of the piston rod (11a) of the pneumatic cylinder (11) is connected to a bracket (12) fixed to the left end on the top wall (5a) of the door (5). Supply and discharge of compressed air are performed to the first and second air chambers of the pneumatic cylinder (11) through a solenoid valve (13), and the compressed air is supplied to the first air chamber. When the compressed air is discharged from the second air chamber, the piston rod (11a) advances and the door (5) is closed,
When the compressed air is supplied to the second air chamber and the compressed air is discharged from the first air chamber, the piston rod (11a)
Exits and the door (5) is opened.

The solenoid valve (13) is a double solenoid, spring center type, 5 port, 3 position switching valve. (13b) When the (left solenoid in FIG. 1) is in the non-excited state, it is switched to the first position shown in FIG. 1, and conversely, the second solenoid (13b) is in the excited state and When the first solenoid (13a) is in the non-excited state, it is switched to the second position, and both solenoids (13a) are switched.
When both (13a) and (13b) are in the non-excited state, the switch is switched to the neutral position by the action of the two springs (13c). When the solenoid valve (13) is at the first position, the compressed air is supplied to the second air chamber of the pneumatic cylinder (11), and the compressed air is discharged from the first air chamber to the atmosphere. . When the solenoid valve (13) is in the second position, the pressurized air is supplied to the first air chamber of the pneumatic cylinder (11), and the pressurized air is discharged from the second air chamber to the atmosphere. Further, when the solenoid valve (13) is at the neutral position, both air chambers of the pneumatic cylinder (11) are respectively open to the atmosphere. Two conduits (1) for communicating the solenoid valve (13) with the air chambers of the pneumatic cylinder (11)
In the middle of 5) (16), variable apertures (17) and (18) are provided respectively, and bypass pipes (19) and (20) are provided in these apertures (17) and (18), respectively. Each bypass pipe (19) (2
0) are provided with check valves (21) and (22) that open only in the direction of the solenoid valve (13).

A door lock device (A) for locking the door (5) is provided on the top wall portion (2a) of the left fixed cover portion (2) of the splash cover (1) as described below. ing.

As shown in FIGS. 2 to 5, on the top wall portion (2a) of the left-side fixed cover portion (2) of the splash cover (1), at a position corresponding to the engaging bar (8) in the front-rear direction, A substantially inverted L-shaped lower support member (25) as viewed from the right side comprising a vertical portion (25a) and a horizontal portion (25b) projecting forward and connected to the upper end of the vertical portion (25a) is fixed, A pair of vertical parts (26a) spaced horizontally in the horizontal direction on the horizontal part (25b) of the lower support member (25)
And a horizontal connecting part (26) connecting the upper ends of both vertical parts (26a).
b) a substantially inverted U-shaped upper support member as viewed from the front (26)
Has been fixed.

A vertical rod (29) having a circular cross section is vertically passed through a through hole (27) formed in a horizontal portion (25b) of the lower support member (25) via a slide bearing (28). Have been. rod
At the lower end of (29), a lock pin (30) that fits into the notch (9) of the engagement bar (8) and engages with the engagement bar (8) is fixed with its axis oriented in the front-rear direction. I have. A compression coil spring (32) (32) (around the rod (29) is provided between the spring support (31) provided on the lock pin (30) in an upwardly projecting shape and the horizontal portion (25b) of the lower support member (25). An urging means) is provided, and the rod (29) is always urged downward by the compression coil spring (32). A plate-shaped rear protrusion (30a) is integrally formed at the rear end of the lock pin (30), and the rear protrusion (30a)
Is guided by the guide (33) fixed to the front surface of the vertical portion (25a) of the lower support member (25), thereby preventing the rod (29) and the lock pin (30) from rotating around the vertical line. . The distance between the horizontal portion (25b) of the lower support member (25) and the top wall portion (2a) of the left fixed cover portion (2) is determined by the notch of the engagement bar (8) with the lock pin (30). The size is such that it can escape upward from (9).

An arm is provided on the horizontal portion (25b) of the lower support member (25).
(34) is fixed so as to project rightward, and a dog
An oscillating limit switch (35) which is activated by (10) and detects the closed end of the door (5) is mounted.

On the connecting portion (26b) of the upper support member (26), a direct acting solenoid actuator (36) for raising the rod (29) against the elastic force of the compression coil spring (32) during operation is provided. The plunger (37) is attached with the downward direction.
The plunger (37) of the solenoid actuator (36) extends downward through the connecting portion (26b), and its lower end is connected to the upper end of the rod (29) via a joint (38). .

The joint (38) comprises a first joint member (39) fixed to the upper end surface of the rod (29) and a second joint member (40) fixed to the lower end surface of the plunger (37). . First joint member (3
9) is a rectangular tube, with both ends open in the front-rear direction.
Fixed to 9). The upper wall portion (39) of the first joint member (39)
A through hole (41) is formed in a), and a plunger (37) is passed through the through hole (41) from above. Second joint member
(40) is a horizontal band-shaped plate long in the front-rear direction, the rear end of which is fixed to the lower end surface of the plunger (37), and the front end of which is located forward of the front end of the horizontal portion (25b) of the lower support member (25) It protrudes.

When the solenoid is excited and the solenoid actuator (36) is activated and the plunger (37) is raised, the second joint member (40) is raised, and the second joint member (40) is raised.
(40) engages with the periphery of the through hole (40) in the upper wall portion (39a) of the first joint member (39), whereby the first joint member (3
9) and the rod (29) are raised, and the lock pin (30) is disengaged upward from the notch (9), so that the lock pin (30) is disengaged from the engagement bar (8). Is done. Also,
The solenoid is de-energized and the solenoid actuator
When the (36) is deactivated, the rod (29) is lowered by the elastic force of the compression coil spring (32), and the lock pin (30) enters the notch (9). ) Engages with the engagement bar (8). At the same time, the plunger (37) is lowered by the action of the joint (38). The connecting portion (26b) of the horizontal portion (25b) of the lower support member (25) and the upper support member (26)
The gap between the rod (29) and the lock pin (30) is notched.
(9) The lower end position that fits inside and the lock pin (30) are notched
The size is set so as not to interfere with the first joint member (39) when moving between the upper end position which escapes upward from (9).

At a position corresponding to the front end of the second joint member (40), a vertical operating rod having a circular cross section for raising the rod (29) when the solenoid actuator (36) is not operated.
(42) is provided through the top wall portion (2a) of the left-side fixed cover portion (2). The top wall of the left fixed cover (2) (2
In the through hole (43) formed in a), a vertical cylindrical body (44) having outward flanges (44a) (44b) at upper and lower ends respectively.
However, it is fitted through the slide bearing (61) in a penetrating manner and rotatably around a vertical axis. Operation levers (45) and (46) for rotating the cylindrical body (44) are screwed into both outward flanges (44a) and (44b) of the cylindrical body (44).
The lower end of the operation rod (42) is rotatably and vertically movable through the cylindrical body (44).

Between the cylindrical body (44) and the operating rod (42),
An inverse cam device (49) for converting rotation of the cylindrical body (44) about a vertical axis into vertical movement of the operation rod (42) is provided. The reverse cam device (49) has a screw cam groove (47) formed on the outer peripheral surface of the lower end portion of the operating rod (42) and a lower outward flange (44b) formed on the lower side of the cylindrical body (44). It is a pin (48) which is fitted and whose tip projects into the cylindrical body (44) and fits slidably in the cam groove (47). Then, by operating the operation levers (45) and (46) to rotate the cylindrical body (44), the operation rod (42) moves up and down by the action of the reverse cam device (49).
When the operating rod (42) is at the lower end position, the upper end thereof is located at a slightly lower height than the second joint member (40) when the solenoid actuator (36) is in a non-operating state (FIG. 2). Similarly, when it is in the upper end position, the upper end raises the second joint member (40) to the upper end position, whereby the lock pin (30) is removed from the notch (9) through the joint (38). The rod (29) is located at a height where the rod (29) can be raised until it escapes upward (see FIG. 5).

When the operating rod (42) is at the upper end position, around the portion of the operating rod (42) projecting upward from the cylindrical body (44), the air chambers of the pneumatic cylinder (11) are exposed to the atmosphere. A valve (50) for communication is provided. A valve body (51) is fixed to the front end of the horizontal portion (25b) of the lower support member (25), and the valve body (51) is airtightly fitted around the operation rod (42). The valve body (51) has a pneumatic cylinder (1
A first port (52) to which a branch pipe (15a) branched from a conduit (15) for supplying and discharging compressed air to and from the first air chamber of 1) is connected.
And a second port (53) to which a branch pipe (16a) branched from a conduit (16) for supplying and discharging compressed air to and from a second air chamber of the pneumatic cylinder (11) is formed. Valve Body (51)
Two annular channels (5 and 5) communicating with both ports (52) and (53)
4) (55) is formed over the entire circumference.

The operating rod (42) is formed with an air flow path (56) extending radially inward from the outer peripheral surface of the upper end thereof and bending downward to reach an intermediate portion of the height. When the operating rod (42) is at the upper end position, the rod (4
2) The opening to the outer peripheral surface is located above the upper end of the valve body (51). When the operation rod (42) is at the upper end position, the lower end of the air flow path (56) is located at the lower annular flow path (55) of the valve body (51).
At a height that matches The operating rod (42) extends radially outward from the lower end of the air flow path (56) to the operating rod (42).
A plurality of branch flow paths (57) that are open on the outer peripheral surface of are formed. When the operation rod (42) is at the upper end position, the air flow path (56) is provided to the operation rod (42) at a height position that matches the upper annular flow path (54) of the valve body (51). ), A plurality of branch channels (58) extending radially outward and opening on the outer peripheral surface of the operation rod (42) are formed. Therefore, when the operating rod (42) rises to the upper end position, the pneumatic cylinder (11)
In both air chambers, conduits (15) (16) and branch pipes (15a)
(16a), port (52) (53), annular flow path (54) (55), branch flow path
(57) It becomes in communication with the atmosphere via the air flow path (56) and the air flow path (56). On the other hand, when the operating rod (42) is at the lower end position, the leading end openings of both branch flow paths (57) and (58) are respectively connected to the valve body.
(51) is closed by the inner peripheral surface,
Both air chambers of (11) are not in communication with the atmosphere.

A pin (59) is screwed into the lower end of the valve body (51) from the outside thereof, and the tip of the pin (59) is attached to the valve body (5).
The pin (59) protrudes into the guide groove (60) formed on the outer peripheral surface of the operating rod (42) and extending in the vertical direction.

The N provided with the door lock device (A) having the above structure
In the C lathe, when the power of the NC lathe is turned on, the solenoid is excited and the solenoid actuator (36) is activated, and the rod (29) and the lock pin (30) move upward (door unlock direction). In this state, the door (5) can be freely opened and closed. In this state, when the button for closing the door (5) is pressed, the solenoid valve (13) is switched to the second position,
The pressurized air is supplied to the first air chamber through the conduit (15), and the pressurized air in the second air chamber is discharged to the atmosphere through the conduit (16) and the bypass pipe (20). As a result, the piston rod (11a) of the pneumatic cylinder (11) advances, and the door (5) is closed. On the contrary, when the button for opening the door (5) is pressed, the solenoid valve (13) is switched to the first position, and the compressed air is supplied to the second air chamber through the conduit (16). At the same time, the compressed air in the first air chamber is discharged into the atmosphere through the conduit (15) and the bypass pipe (19). As a result, the piston rod (11a) of the pneumatic cylinder (11) retracts, and the door (5) is opened (FIG. 1).
reference). When the normal door (5) is opened and closed as described above, the operating rod (42) is at the lower end position, and the pressure air in both air chambers of the pneumatic cylinder (11) is prevented from leaking into the atmosphere by the valve (50). Have been. Buttons for opening and closing the door (5) are provided inside and outside the splash cover (1).

When the start button for executing the machining program is pressed after closing the door (5), the control device causes the dog (10) of the engaging bar (8) to activate the limit switch (35). After confirming that the door has been switched and the door (5) has reached the closed end, the solenoid is switched to non-excitation, and the solenoid actuator (36) is deactivated. Then
Due to the gravity and elastic force of the compression coil spring (32), the rod (2
9) is lowered, the lock pin (30) fits into the notch (9) of the engagement bar (8) and is engaged with the engagement bar (8), and the rod (29) and the lock pin (30) are engaged. ) Is urged downward by the elastic force of the compression coil spring (32), so that the door (5)
Is locked (see FIGS. 2 and 3).

After the machining is completed, that is, when the control device reads an end command code of the machining program, the solenoid is excited, the solenoid actuator (36) is activated, and the plunger (37) is raised, so that the joint (38) The rod (29) is raised against the elastic force of the compression coil spring (32), and as a result, the lock pin (30) is notched.
The lock pin (30) is released upward from (9), the engagement of the lock pin (30) with the engagement bar (8) is released, and the door lock is released.

When the power of the NC lathe is turned on, the worker may open the door (5), enter the splash cover (1), and work with the door (5) closed. is there. In this case, if the power of the NC lathe is turned off due to an accident such as a power failure during the work, the solenoid is de-energized and the solenoid actuator (36) is switched to the non-operating state, and the compression coil spring (32) is turned off. Rod by elastic force
(29) is lowered, the lock pin (30) is automatically engaged with the engagement bar (8), and is urged downward (toward the door lock direction). As a result, the door (5) is locked, and the worker cannot open the door (5) from inside the splash cover (1). When the power of the NC lathe is turned off, the solenoid valve (13)
(13a) and (13b) are de-energized, and are switched to the neutral position by the action of the spring (13c).

At this time, when the cylindrical member (44) is rotated by operating the lower operation lever (46) in the splash cover (1), the operation rod is operated by the action of the reverse cam device (49).
(42) is raised and the second end is moved by the upper end of the operating rod (42).
The joint member (40) is pushed up, and the rod is inserted through the joint (38).
(29) is raised against the elastic force of the compression coil spring (32) to reach the upper end position. Then, the lock pin (30) escapes upward from the notch (9) of the engagement bar (8), and the lock pin (30)
Is disengaged from the engagement bar (8) and the door (5) is unlocked, and as a result, the door (5) can be removed from within the splash cover (1).
Can be opened (see FIG. 5).

When the operating rod (42) reaches the upper end position, the pressurized air in the first air chamber of the pneumatic cylinder (11) is discharged into the atmosphere via the conduit (15), and is discharged to the atmosphere. ,
The air is discharged into the atmosphere through the branch pipe (15a), the first port (52), the annular flow path (54), the branch flow path (58), and the air flow path (56). Therefore, the driving force of the pneumatic cylinder (11) in the closing direction of the door (5) can be released, so that the door (5) can be quickly opened with a relatively small force.

Here, if the second air chamber of the pneumatic cylinder (11) merely communicates with the atmosphere via the throttle (18) of the conduit (16), the air hardly flows into the second air chamber. ,door
Opening (5) creates a relatively large resistance.
The air chamber communicates with the atmosphere through the conduit (16), the branch pipe (16a), the second port (53), the annular flow path (55), the branch flow path (57), and the air flow path (56). Because of this, the air flows into the second air chamber quickly, and the door (5) can be quickly opened with a small force.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of an NC lathe provided with a door lock device according to the present invention.

FIG. 2 shows the door closed and locked in FIG.
FIG. 2 is a sectional view corresponding to an enlarged section taken along line II-II.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a sectional view corresponding to FIG. 2 and showing a state in which a door lock is released from inside the splash cover.

[Explanation of symbols]

 (1): Splash cover (4): Opening (5): Door (8): Engagement bar (11): Pneumatic cylinder (29): Rod (30): Lock pin (32): Compression coil spring (biased) Means) (36): Solenoid actuator (38): Joint (39): First joint member (40): Second joint member (42): Operating rod (50): Valve (A): Door lock device

Claims (3)

[Claims] A lock device for a door that opens and closes an opening formed in a splash cover of a machine tool, the lock member being capable of engaging with the door when the door is closed and fixing the door outside the splash cover, A door lock provided with an urging means for urging the lock member in the door lock direction, and further comprising a solenoid actuator for moving the lock member in the door lock release direction against the urging force of the urging means when activated. In the device, an operation rod for moving the lock member in the door unlocking direction when the solenoid actuator is not operated is provided so as to penetrate the splash cover and move in the axial direction thereof,
A door lock device for a machine tool, comprising a transmission means provided between an operation rod and a lock member for converting the movement of the operation rod in the axial direction to the movement of the lock member in the door unlocking direction. The door is opened and closed by an opening / closing drive means, and the driving force of the opening / closing drive means in the door closing direction is caused by the movement of the operating rod when the lock member moves in the door unlocking direction. 2. The door lock device for a machine tool according to claim 1, further comprising a driving force releasing unit that releases the driving force. 3. The opening / closing drive means is a fluid actuator, and the driving force release means is provided around the operating rod.
3. The door lock device for a machine tool according to claim 2, wherein the valve is a valve for communicating both pressure chambers of the fluid actuator to the atmosphere when the operating rod moves to move the lock member in the door unlock direction.