JPH0523852B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a hydraulic press device, and particularly to a press-fitting and
The present invention relates to a molding press device that performs micro-feeding or micro-feeding press-fitting and molding with vibration.

(Prior art) As a conventional press machine that performs micro-feed or micro-feed press-fit molding with such vibration, for example, there is a vertical ultrasonic vibration punch press disclosed in Japanese Patent Publication No. 38-25598, which has a vibration frequency of 20 KHz or more. It has been proposed to obtain a smooth machined surface of Bakelite etc. by applying ultrasonic vibration. For example, special public relations in 1983
-23959 publication has a frequency of 5 to 100Hz and a load time of 0.2
A vibratory finishing punching method is disclosed in which axial vibration with an amplitude of 0.5 to 2 times the plate thickness is applied to the punch for ~20 seconds to locally heat soften and punch out the resin material.

All of these techniques utilize local thermal softening or partial deformation of the workpiece material due to vibration, and these techniques utilize the press member generated by micro-feeding with vibration or step-wave micro-feeding as disclosed in the present invention. No technology is disclosed that utilizes the reduction in friction between the pressed member and the pressed member.

(Problem to be solved by the invention) In conventional press fitting, for example, in a press-fitting press device for serration bolts, five or six serration bolts are simultaneously inserted into the object to be press-fitted and stopped instantly by a mechanical stopper. This requires a very large force to press in, and each time the number of bolts to be press-fit changes, it is necessary to use a press device with an output commensurate with the number of bolts to be press-fitted.
For this reason, a separate large-sized press-fitting press device was required for each number of press-fitting bolts, and preparations for pressure setting of the press-fitting control valve were required to change the output, resulting in increased costs, troublesome handling and maintenance, and reduced reliability. . Moreover, instantaneous press-fitting can result in defective products, such as bent or broken serration bolts, or insufficient press-fit depth, both in the pressed part and the press part, and also in damage to the press equipment. .

The purpose of the present invention is to solve the above-mentioned conventional problems, to avoid causing destruction, fatigue, or malfunction to any of the pressed members, press members, and press equipment, to be compact, and to be able to handle increased loads such as the number of press-fit bolts. The objective is to provide a press device that can be widely used.

(Means for Solving the Problems) Therefore, the present invention has solved the above-mentioned problems by providing a press device according to the claims.

(Function) The present inventor believes that the above-mentioned conventional problems are caused by the fact that in conventional press equipment, the friction coefficient between the press-fitting surface and the press-fitting surface is uneven, resulting in considerable variation in the press-fitting force. In this invention, several Hz
Micro feed or number with vibrations ranging from hundreds of Hz to several hundred Hz
Since the press equipment uses step-wave micro-feeding at frequencies ranging from Hz to several hundred Hz, when press-fitting and forming the press member into the pressed member, the friction coefficient between the press-fitting surface and the press-fitting surface is determined by the relative Sliding motion creates a fit between the press-fitting surface and the press-fitted surface, reducing the coefficient of dynamic friction, reducing the amount of press-fitting required for press-fitting and forming to less than 1/3, making it possible to downsize the press equipment and improve processing speed. The finish was found to be good.

(Example) Next, a press apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 2 shows a schematic side view of the entire press apparatus. A servo cylinder 5 having a rod 5 for supporting a press member 4 such as a serration bolt that is pressed into a pressed member 3 fixed to a table 2 of the main body 1 is fixed to a frame 6 of the main body 1. Pressure oil is supplied to the servo cylinder 5 via a servo valve 7 from a hydraulic power source (not shown). A schematic block diagram of the control device of the press machine in FIG. 2 is as shown in FIG.
is controlled by the control signal of the servo amplifier 8, and the servo amplifier 8 has a frequency range of several Hz to several hundred as shown in Fig. 3.
A command signal generator 9 is connected to input basic command signals 11 and 12 for commanding a Hz sine wave and a desired minute feed, and at the same time, a servo amplifier 8 detects the amount of movement of the servo cylinder 5 rod 5'. A position signal from a differential transformer 10, which is a position sensor, is input to a differential transformer amplifier 11, amplified, and input as a feedback signal. Therefore, the servo amplifier 8 performs voltage/current conversion so that the error signal between the command signal and the feedback signal becomes 0, and outputs the current to the servo valve 7 as a control signal. Therefore, the servo cylinder 5 rod 5' always moves in accordance with the command signal from the command signal generator 9. During operation, the command signal generator 9 generates a sine wave 1 with a frequency of several Hz to several hundred Hz and an amplitude of several + μm to several mm as shown in the third figure.
A command signal including 1 and a desired minute feed 12 is input, and the servo amplifier 8 is configured to follow the command signal.
output to the servo valve 7. Servo valve 7
operates the servo cylinder 5 and causes the third rod 5' to move.
A movement is performed according to the illustrated command signal. The movement of servo cylinder 5 rod 5' is servo cylinder 5.
Position detection is performed by a differential transformer 10 attached to the differential transformer 10, and the position signal generated by the differential transformer 10 is amplified by a differential transformer amplifier 11 and inputted as a feedback signal to the servo amplifier 8, and the servo amplifier 8 receives the command signal and the position signal. The voltage/current is converted so that the error signal with the feedback signal becomes 0, and the current is output as a control signal to the servo valve 7, thereby forming a closed loop. As a result, the rod 5' output according to the command signal is obtained, and the press member 4 supported on the servo cylinder rod 5' is pressed against the pressed member 3 at a frequency of several Hz to several hundred Hz, several + μm to several
It is press-fitted and molded in small distances at a time, accompanied by vibrations with an amplitude of 1 mm.

FIG. 4 shows a basic command signal output waveform diagram suitable for molding, the command signal 13 being generated by the command signal generator 9 in the same manner as the command signal of FIG.

According to the example press equipment, when press-fitting a serration bolt into a material to be press-fitted with a uniform press-fitting margin, a press-in force of about 2 tons was conventionally required per bolt, but the press-fit force is about 1/4th, or 500 kg. I was able to press it in with the pressure of For this reason, the 3-ton press of the present invention can now be used instead of the conventional 5-6 serration bolts that were press-fitted using a 12-ton press.
Moreover, since a large force is not instantaneously applied, the occurrence of breakage, fatigue, and malfunction of either the press member to be pressed or the press apparatus can be greatly reduced.

FIG. 5 further shows a basic command signal output waveform diagram that is an alternative to the command signals of FIGS. 3 and 4. The command signal 14 is sent from the command signal generator 9 to the servo amplifier 8 to cause the servo cylinder 5 to perform step-wave minute feed (feed amount + μm to several mm) of several Hz to several hundred Hz.
The feedback signal of the differential transformer 10 is input to the servo valve 7 via the command signal 11 and 12 of FIG.
is the same as In this case, since the servo cylinder 5 always pushes downward, there is an advantage that there is no need to clamp the pressed member 3 from above. The press apparatus using this command signal 14 can obtain other effects substantially similar to those using the command signal shown in FIG. 3.

FIG. 6 is a schematic block diagram showing a control device for a press apparatus according to an embodiment of the present invention, which is a different embodiment from that shown in FIG.
The pressure is measured by the pressure measuring devices 15 and 15', and is inputted as a feedback signal to the servo amplifier 8' from the differential pressure signal amplifier 17 which outputs a pressure difference signal between both end chambers via the pressure amplifier 16, and then outputs a command signal. When the generator 9 outputs the stepped wave minute feed command signal 14 shown in FIG. 5 to the servo amplifier 8', the servo cylinder 5 can be periodically pressurized minute by minute as shown in FIG.

(Effects of the Invention) As explained above, according to the press apparatus of the present invention, the servo cylinder generates a minute feed command signal having vibrations of several Hz to several hundred Hz, or
Press-fitting and forming are performed in accordance with the Hz step-like minute feed command signal, so there is no need for large amounts of force all at once.
In addition, due to the relative sliding motion between the press-fitting surface of the pressed member 3 and the press-fitting surface of the press member 4, the dynamic friction coefficient decreases, so that press-fitting and forming can be performed with even smaller force. It became. By press-fitting and forming with a small force on top of that, there is no breakage, fatigue, or malfunction of the pressed member, press member, or press equipment, and press-fit and molded products can be produced with a good yield. Ta.
Furthermore, according to this press device, by pressing while applying pressure in small amounts at regular intervals, the finish of the pressed parts and pressed parts is much clearer and cleaner than the finish of the pressed parts and parts that are pressed in one press, as they have been pressed many times. You can get a face. Therefore, since the press apparatus of the present invention is small, it is inexpensive and space-saving, and it can also widely respond to changes in the number and load, reducing equipment costs and saving energy, making it extremely useful.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram showing a control device of a press apparatus according to an embodiment of the present invention, FIG. 2 is a schematic side view of a press apparatus according to an embodiment of the present invention, and FIGS. Basic command signal output waveform diagrams output from the command signal generator shown in the figures are shown, respectively, and FIG. 6 is a schematic block diagram showing a control device for the press apparatus according to the embodiment, which is different from that shown in FIG. 1... Main body, 3... Pressed member, 4... Press member, 5... Servo cylinder, 5'... Rod,
7...Servo valve, 8,8'...Servo amplifier,
9... Command signal generator, 10... Differential transformer (position sensor), 15, 15'... Press-fit measuring device (position detection sensor).

Claims (1)

[Claims] 1. A servo cylinder fixed to the main body and having a rod that supports the press member in a reciprocating manner toward the pressed member fixed to the main body, and a servo valve that supplies pressure oil from a hydraulic source to the servo cylinder. , a servo amplifier that inputs a command signal and a feedback signal to control the servo valve and outputs a control signal, and a servo amplifier that has a servo cylinder that vibrates at a frequency of several Hz to several hundred Hz. a command signal generator that inputs the command signal that causes a stepwise wave micro-feed of Hz;
A press apparatus comprising: a position detection sensor that detects the movement of the servo cylinder; and a feedback device that inputs a signal from the position detection sensor and inputs the signal as the feedback signal to the servo amplifier.