JPH042366B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an intermittent feed control device that is effective when placed in a hydraulic circuit for feeding cutting tools provided in a machine tool for cutting, such as a lathe or a drill press.

[Conventional technology]

Conventionally, in machine tools such as lathes and drill presses, when the cutting tool is fed for processing using a hydraulic actuator such as a hydraulic cylinder, long chips are generated continuously and get entangled with the cutting tool and the workpiece, damaging the machined surface. An intermittent feed control device is installed in the hydraulic circuit for feeding the cutting tool to control the hydraulic actuator to move intermittently, such as forward/backward operation or forward/stop operation, so as not to cause the blade to move or endanger the operator. This allows cutting to be performed while cutting chips into pieces.

[Problem that the invention seeks to solve]

However, this type of intermittent feed control device uses an electric timer to repeatedly turn on and off the electromagnet of the electromagnetic switching valve at predetermined intervals, or continuously rotates the switching valve using an electric motor to control the hydraulic actuator. Since the machine operates intermittently to control the feed of the cutting tool, an electric circuit is required separate from the hydraulic circuit, which makes handling and maintenance difficult and difficult to install in the existing hydraulic circuit. The dot was hot.

The present invention solves this problem, and has a simple configuration in which piping is provided to connect to the pressure passage, load passage, and discharge passage in the device body, and it can be easily placed in an existing hydraulic circuit, and the hydraulic An object of the present invention is to provide an intermittent feed control device that allows reliable intermittent operation of an actuator.

[Means for solving problems]

The structure of the present invention, which has been made to solve such problems, is that an action chamber is provided in the main body of the device, which has a pressure passage into which pressure liquid flows, a load passage connected to the hydraulic actuator side, and a discharge passage connected to the low pressure side. The piston moves in the axial direction by flowing pressure liquid into the chamber or discharging the liquid in the working chamber, increases the pressure of the pressure liquid, and discharges it into the load passage. A switching valve body is provided to reciprocate the piston by switching the working chamber of the piston between the pressure passage side and the discharge passage side, and a pilot fluid that switches and controls the direction of action of the pilot liquid acting on the switching valve body. The piston and the pilot switching valve body are arranged substantially parallel to each other, and one end of the coaxial direction protrudes from the outside of the device body, and one of the protruding portions has elasticity as a thin plate-like operating member. and a locking member is provided on the other side, and the operating member and the locking member are brought into contact with each other via an elastic member that absorbs the shock when they come into contact, so that the piston and the pilot switching valve body are interlocked. The abutting position between the operating member and the locking member can be freely changed, and two abutting positions are provided with an interval in the axial direction.

[Effect]

In this configuration of the present invention, by flowing the pressure liquid into the pressure passage of the device main body, the piston is moved in the axial direction by the pressure liquid flowing into the action chamber via the switching valve body, and the operating member and the locking member are moved. The pilot switching valve element is moved by contacting the piston at one contact position via an elastic member, and the switching valve element is pilot operated by the movement of the pilot switching valve element to change the direction of movement of the piston, thereby switching the piston. When the piston is moved by a predetermined amount in the switched direction, the operating member and the locking member are brought into contact with each other via the elastic member. When the two pistons come into contact with each other at this position, the pilot switching valve element is operated to return, and the switching valve element is pilot operated to switch the direction of movement of the piston again.
By repeating this operation, the pressure liquid increased by the piston is intermittently discharged from the load passage, and the hydraulic actuator connected to the load passage is reliably operated intermittently. The piston and the pilot switching valve element are mechanically interlocked by contact between the operating member and the locking member, and the piston and the switching valve element can be automatically operated by the pressure liquid and the pilot liquid. It has a simple configuration with piping connected to the pressure passage, load passage, and discharge passage, and can be easily installed in an existing hydraulic circuit.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In Fig. 1, 1 is the main body of the device, which includes a pressure passage P through which pressure liquid flows, a load passage A connected to the hydraulic actuator side, and a discharge passage R connected to the low pressure side.
, a piston 2 for increasing the pressure liquid inside and performing a discharge action, a switching valve body 3 for reciprocating the piston 2, and a pilot switching valve body 4 for pilot operating the switching valve body 3. It is equipped with The piston 2 is fitted into a hole 5 of different diameters provided through the main body 1 of the device so as to be able to move freely in the axial direction. A pressure intensifying chamber 8 is formed by a small diameter portion continuous to the pressure chamber 8, and a rod portion 9 continuous to the end of the small diameter portion protrudes outside the main body 1 of the device. The switching valve body 3 has a spool shape, and is fitted into the fitting hole 10 so as to be freely movable in the axial direction, forming pilot operating chambers 11 and 12 at both ends, and by moving in the axial direction, it connects the pressure passage P and the discharge passage R. Two communication passages 13 and 1 that communicate with each of the working chambers 6 and 7 of the piston 2
They are provided so that they can be switched and communicated with each other. The pilot switching valve body 4 has a spool shape, is arranged approximately parallel to the piston 2, and is fitted into the fitting hole 15 so as to be movable in the axial direction.By moving in the axial direction, the pilot operating chambers at both ends of the switching valve body 3 are closed. 11 and 12 are provided so as to be switched and communicated with a pressure passage P and a discharge passage R via pilot passages 16 and 17. and,
The pilot switching valve body 4 is connected to the rod portion 9 of the piston 2.
One end 18 in the coaxial direction protrudes outside the main body 1 of the apparatus. Reference numeral 19 denotes a throttle valve section disposed in the communication passage 14, and as shown in FIG. A poppet valve body 23 fitted around the outer periphery of the cylindrical member 21 is provided to adjust the liquid flow rate and is seated on a valve seat 25 by the force of a spring 24 so that the liquid from the working chamber 7 flows freely. 26 and 27 are check valves, and the throttle valve part 19
A branch passage 28 that branches from the communication passage 14 on the side of the working chamber 7 and communicates with the pressure intensification chamber 8 and a communication passage 29 that communicates between the pressure intensification chamber 8 and the load passage A are arranged respectively, and when the piston 2 moves in the axial direction, The pressure liquid is increased in pressure and discharged into the load passage A. 30
is the rod portion 9 of the piston 2 that protrudes outside the device body 1.
This operating member is made of an elastic spring material or the like and is formed into a thin plate shape, and its free end is loosely fitted into the projecting end 18 of the pilot switching valve body 4. 31,
Reference numeral 32 designates a locking member provided on the protruding end 18 of the pilot switching valve body 4, which causes the pilot switching valve body 4 to interlock with the piston 2 when the operating member 30 comes into contact with it. Elastic members 33 and 34 are arranged to absorb the impact when the member 30 abuts. The locking member 32 is screwed onto the protruding end portion 18 and is provided so as to be freely changeable in position in the axial direction.

FIG. 3 shows an intermittent feed control device 40 according to the present invention.
36 is a hydraulic cylinder as a hydraulic actuator that feeds and controls the cutting tool of the machine tool, 37 is an electromagnetic switching valve that operates the hydraulic cylinder 36 to move forward, backward, and stop, and 38 is a flow rate adjustment valve with a check valve, which throttles and controls the liquid discharged from the hydraulic cylinder 36 into the circuit 42 of the two circuits 41 and 42 connecting the hydraulic cylinder 36 and the electromagnetic switching valve 37, so-called meter-out. It is placed so that it can be controlled. Intermittent feed control device 40 of the present invention
The pressure passage P is connected to the circuit 41, and the load passage A is connected to the hydraulic cylinder 36 side circuit 4 of the flow rate adjustment valve 38 with a check valve.
2, the discharge passage R is connected to a liquid tank 43 as a low pressure side by piping or the like.

Next, the operation of this configuration will be explained.

The state shown in FIGS. 1 to 3 is the state of the electromagnetic switching valve 37.
is in its neutral switching position, cutting off pressure fluid from the pressure source side, and the hydraulic cylinder 36 is at rest.
In this state, when the electromagnetic switching valve 37 is operated to the right switching position in order to move the hydraulic cylinder 36 forward, that is, to obtain cutting feed, pressure liquid flows into the circuit 41 and the circuit 42 is connected to the low pressure side, so that the hydraulic cylinder 36 moves forward. 36 moves to the right under speed control by a flow rate regulating valve 38 with a check valve. A part of the pressure liquid flowing into the circuit 41 flows into the pressure passage P of the intermittent feed control device 40 and passes through the three switching valve body passages 14 and the throttle valve portion 19.
It flows into the action chamber 7 through the piston 2 to move the piston 2 to the left, and flows into the pressure increase chamber 8 through the branch passage 28 and check valve 26 to fill it. At this time, the action chamber 6
The liquid flows to the discharge passage R liquid tank 43 via the communication passage 13 and the switching valve body 3. In addition, the pressure liquid in the pressure passage P is used as a pilot liquid to control the pilot switching valve body 4.
It flows into the pilot action chamber 11 via the pilot passage 16 and holds the switching valve body 3 in the right switching position. The piston 2 moves to the left by a predetermined amount and the operating member 30
When it comes into contact with the locking member 31, the pilot switching valve body 4 moves to the left in conjunction with the piston 2, switching the pilot operating chamber 11 to the discharge passage R and the pilot operating chamber 12 to the pressure passage P (right). The switching valve body 3 is moved to the left by the pilot liquid flowing into the pilot action chamber 12, thereby switching the communication passage 13 to the pressure passage P and the communication passage 14 to the discharge passage R (right switching position). . The piston 2 moves to the right as pressurized liquid flows into the working chamber 6, throttles the liquid in the working chamber 7, lifts the poppet valve body 23 of the valve portion 19 from the valve seat 25, and transfers the valve body 3 to the communication passage 14. At the same time, the pressure liquid in the pressure increase chamber 8 is increased in pressure by an amount corresponding to the pressure receiving area difference between the action chamber 6 and the pressure increase chamber 8, and is passed through the communication path 29 and the check valve 27. A discharge action is applied to the circuit 42 from the load passage A. Due to the action of this pressurized discharged liquid, the hydraulic cylinder 36 is moved backward by an amount corresponding to the discharged amount. When the piston 2 moves to the right by a predetermined amount and the operating member 30 comes into contact with the locking member 32, the pilot switching valve body 4 is operated to move to the right switching position shown in the figure, and the switching valve body 3 is moved back to the switching position shown in the figure. Then, the above-described operation is automatically repeated as long as the pressure liquid flowing into the pressure passage P is not interrupted. Therefore, the hydraulic cylinder 36 repeatedly moves forward and backward to perform intermittent cutting feed operations. Further, the return of the hydraulic cylinder 36 is carried out by operating the electromagnetic switching valve 37 to the left switching position so that the pressure liquid flows into the circuit 42 and the circuit 41 is connected to the low pressure side. Then, the intermittent feed control device 40 stops because the pressure passage P is connected to the low pressure side.

With this operation, the intermittent feed control device 40 mechanically interlocks the piston 2 and the pilot switching valve body 4 through contact between the operating member 30 and the locking members 31 and 32, and causes the pressure liquid to flow into the pressure passage P. Since it operates automatically, it can be easily installed in an existing hydraulic circuit with a simple configuration that requires piping to connect to the pressure passage P, load passage A, and discharge passage R. Also,
By moving the throttle valve body 20 of the throttle valve part 19 in the axial direction to adjust the flow rate of the pressure liquid flowing into the working chamber 7, the moving speed of the piston 2 is changed. The number of times can be adjusted to a desired value, and one locking member 32
By adjusting the arrangement position and changing the contact position with the operating member 30, the amount of movement of the piston 2, that is, the amount of liquid discharged, is changed, so this operation adjusts the intermittent time in the intermittent operation of the hydraulic cylinder 36 to a desired value. It is possible to obtain the optimum intermittent feed control according to the application. Furthermore, the interlocking operation between the piston 2 and the pilot switching valve body 4 is achieved by attaching an elastic thin plate-like operating member 30 to the locking members 31, 32 via elastic members 33, 34 disposed on the locking members 31, 32. Therefore, when the movement of the piston 2 is adjusted at a very small speed, the pilot switching valve body 4 can be moved quickly and well due to the accumulated elastic force of the operating member 30 after the contact, and high-speed adjustment is also possible. In this case, the elastic deflection of the operating member 30 and the cushioning action of the elastic members 33 and 34 combine to absorb the impact and reduce the generation of operating vibration and operating noise to an extremely small level compared to conventional electromagnets. things can be reduced.

FIG. 4 is a simplified symbol diagram of an intermittent feed control device showing another embodiment of the present invention. To explain the difference in structure from the first embodiment, the pressure increasing chamber is operated in the action chamber 7 on the rod side of the piston 2. In addition, the check valve function of the throttle valve section 19 is omitted, and the same effect as described above is obtained.

〔Effect of the invention〕

As explained above, according to the intermittent feed control device of the present invention, the device main body has a pressure passage into which pressure liquid flows, a load passage connected to the hydraulic actuator side, and a discharge passage connected to the low pressure side. a piston provided to move in the axial direction by flowing pressure liquid into the chamber or discharging liquid from the action chamber, thereby increasing the pressure of the pressure liquid and discharging it into the load passage;
A switching valve body that moves in the axial direction under the action of a pilot liquid and switches the working chamber of the piston between the pressure passage side and the discharge passage side to reciprocate the piston, and a pilot that acts on the switching valve body. It is equipped with a pilot switching valve body that switches and controls the direction of action of the liquid, and the piston and the pilot switching valve body are arranged substantially parallel, with one coaxial end protruding from the outside of the device body, and either one of the protruding parts A thin plate-like operating member having elasticity is fixed to one side, and a locking member is provided on the other side, and the operating member and the locking member are brought into contact with each other through an elastic member that absorbs a shock when they come into contact with each other. The pilot switching valve body is interlocked with the operating member, and the contact position between the operating member and the locking member is changeable, and two contact positions are provided with an interval in the axial direction. It can be easily installed in an existing hydraulic circuit with a simple configuration in which piping is provided to connect to the pressure passage, load passage, and discharge passage.

In addition, by changing the contact position between the operating member and the locking member, the amount of movement of the piston, that is, the amount of liquid discharged, is changed, so this operation allows the intermittent time in the intermittent operation of the hydraulic actuator to be adjusted to a desired value. Optimal intermittent feed control can be obtained depending on the application. Furthermore, since the interlock between the piston and the pilot switching valve body is obtained by abutting an elastic thin plate-like operating member and a locking member via an elastic member, even if the movement of the piston is adjusted at a slight speed, The accumulated elastic force of the operating member after contact allows the pilot switching valve body to be moved quickly and effectively, and when the movement of the piston is adjusted at high speed, the elastic deflection of the operating member and the cushioning action of the elastic member are Combined, this has the effect of absorbing impactful contact and reducing the generation of operating vibrations and operating noise to an extremely small level compared to conventional electromagnets.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of an intermittent feed control device showing an embodiment of the present invention, Fig. 2 is a sectional view taken along the line - in Fig. 1, and Fig. 3 is a layout of the intermittent feed control device of the present invention. FIG. 4 is a simplified symbol diagram of an intermittent feed control device showing another embodiment. DESCRIPTION OF SYMBOLS 1... Device body, 2... Piston, 3... Switching valve body, 4... Pilot switching valve body, 30... Operation member, 31, 32... Locking member, P... Pressure passage, A... Load passage, R...discharge passage.

Claims (1)

[Claims] 1. The main body of the device has a pressure passage through which pressure liquid flows, a load passage connected to the hydraulic actuator side, and a discharge passage connected to the low pressure side. The piston moves in the axial direction to increase the pressure of the pressure liquid and discharge it into the load passage, and the piston moves in the axial direction by the action of the pilot liquid and separates the working chamber of the piston between the pressure passage side and the discharge passage side. a switching valve body provided to reciprocate a piston in switching communication with the switching valve body, and a pilot switching valve body for switching and controlling the direction of action of a pilot liquid acting on the switching valve body,
The piston and the pilot switching valve body are arranged approximately parallel to each other, with one end in the coaxial direction protruding from the outside of the device body, and an elastic thin plate-shaped operating member is fixed to one of the protruding parts and engaged with the other. A stop member is provided, and the operating member and the locking member are provided so as to be able to freely come into contact with each other via an elastic member that absorbs a shock when they come into contact, and are provided so that the piston and the pilot switching valve body are interlocked, and the operating member and the locking member are interlocked. An intermittent feed control device in which the contact position with a member is freely changeable and the contact positions are provided at two locations spaced apart in the axial direction.