JPH039983Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Field of Industrial Application) This invention relates to a clamping state detection device for a vise, and more specifically to a device for automatically detecting the success or failure of the clamping state of a workpiece in a clamping type vise using fluid pressure. (Prior Art and its Problems) In this specification, the movement of each part toward the side that tightens the workpiece is referred to as ``forward''. When using a conventional vise, the workpiece is set between the fixed jaw and the movable jaw, and the movable jaw of the vise is manually rotated by the screw 17 until it is close to the workpiece set position. The movable jaw is moved (hereinafter referred to as manual movement), and then the movable jaw is further moved by fluid pressure (generally hydraulic pressure or pneumatic pressure) (hereinafter referred to as fluid pressure movement) to tighten the workpiece (hereinafter referred to as tightening force application), and the workpiece is tightened. The tightening condition is adjusted by the operator while directly checking the condition. However, as machine tools have recently become larger, faster, and more labor-saving (robotic), it has become increasingly difficult for workers to directly check the tightening state of the workpiece using a vise or the like positioned on the processing table. Touching has become extremely dangerous. For this reason, when an operator tightens a workpiece in a vise, () the workpiece is tightened without being set in the vise, () the workpiece is small and the fluid pressure is low during manual movement. A situation where the workpiece is tightened with a gap greater than the movable range, () A situation where the workpiece is set correctly in the vise but the tightening force is insufficient and the workpiece is not completely tightened, ( ) Currently, it is not possible to correctly determine abnormal conditions, such as when a workpiece is correctly set in a vise but fluid pressure is not supplied and the workpiece is not tightened correctly. It takes extra time to sufficiently check these conditions, which poses a problem in terms of operating efficiency of the processing machine. (Summary of the invention) The purpose of this invention is to automatically detect the clamping state of a workpiece as described above in a fluid pressure clamping type vise. Therefore, in this invention, a stroke detection switch 43 is provided near the manual shaft to detect movement of the drive shaft in the tightening direction.
and a pressure detection piston 3 housed in the cylinder.
0, an elastic pressing mechanism interposed between the piston and the fixed member, and a pressure detecting switch 33 provided near the piston; and a pressure detecting piston branched from the pressure fluid supply mechanism. The gist is to provide a liquid guide path that communicates with the housed cylinder, and to detect the tightened state of the vise from the detected state of a stroke detection switch and a pressure detection mechanism. (Embodiment) The attached drawing shows an example of a vise equipped with the detection device of this invention, and the main parts include a base 2, a fixed jaw 3, a movable jaw 4, a drive shaft 5, and its large diameter portion 7. , a balance block 8, a pressure detection section, and a stroke detection section. The base 2 is made of a highly rigid casting material and is formed into a box shape. A fixed jaw 3 is integrally formed upwardly projecting at one end of the base 2. The upper surface of the base 2 constitutes a guide surface 9 for the movable jaw 4. ing. The movable jaw 4 is installed on this guide surface 9 so as to be able to slide in the workpiece tightening direction (left-right direction in the figure). The drive shaft 5 extends in the tightening direction and is rotatably and slidably supported by the base 2. A large diameter portion 7 integrally formed at the end of the drive shaft 5 on the fixed jaw 3 side is slidably accommodated in a cylinder in a shaft hole of the base 2. Furthermore, an engaging portion 11 such as a tightening handle is provided at the end of the drive shaft 5 on the opposite side from the large diameter portion 7.
is formed. Plate 1 is attached to the fixed jaw 3 side end of base 2.
3 is fixed, and a balance block 8 is provided between the plate 13 and the fixed jaw 3 and base 2.
is interposed, one side of which is in contact with the plate 13, a part of the upper side of the opposite side is in contact with the back of the fixed jaw 3, and a part of the lower side is in contact with the end surface of the base 2. . A screw 17 is formed in the middle portion of the drive shaft 5, and a nut 18 is screwed into the screw 17. The upper part extends inside the movable jaw 4 and has a downward slope on the side corresponding to the fixed jaw 3. On the other hand, a recess is formed on the inner surface of the movable jaw 4 corresponding to this slope, and the flat part of the hemispherical piece 20 rotatably housed in the recess is in contact with the slope of the nut 18. Also, an adjustment screw 2 is attached to the part of the movable jaw 4 that corresponds to the opposite side of the slope of this nut 18.
2 is screwed in, and its tip is in contact with the nut 18. Therefore, by operating this adjustment screw 22, the relative position between the movable jaw 4 and the nut 18 can be adjusted. Coil spring 19 accommodated in the shaft hole of large diameter portion 7
constantly presses the balance block 8 toward the plate 13 via the ball 21. The liquid guide path 6 formed in the plate 13 is connected to an appropriate pressure liquid supply source (not shown) on the upstream side, and the downstream end is connected to a balance block 8.
The piston 30 of the base 2 is opened into a cylinder within the shaft hole, and the large diameter portion 7 of the base 2 is opened into a cylinder within the shaft hole. Here, the opening positions of the liquid guide paths 6 are respectively on the side farthest from the plate 13. The detection device of this invention is applied to a vise having the basic structure as described above, and is composed of a pressure detection section and a stroke detection section. In the pressure detection section, a support rod 31 is fixed to approximately the center of the inner surface of the plate 13 and protrudes in the tightening direction, and a disc spring 3 provided at the tip of the support rod 31 is fixed.
2 is accommodated in the axial hole of a pressure detection piston 30 which is slidably accommodated in the axial hole of the balance block 8. That is, the piston 30 is always pressed against the balance block 8 by the disc spring 32. Also, near this piston 30, a pressure detection switch 33 is installed on the inner wall of the base 2.
is permanently installed. In the stroke detection section, a flanged rod 41 for stroke detection is slidably supported by the balance block 8, and the flanged portion and the plate 13 are slidably supported.
A coil spring 42 is interposed between the rod 4 and
1 is pressed toward the movable shaft. Further, the end portion on the movable shaft side faces the large diameter portion 7. A stroke detection switch 43 is fixedly supported on the inner wall of the base 2 near the flange of the rod 41. The pressure detection switch 33 and the stroke detection switch 43 are both non-contact type proximity switches that are normally kept off and turned on when the object approaches a certain level. All of these switches are off in the initial state, which will be described later. Next, the effect will be explained. First, the initial state will be explained. When the drive shaft 5 is manually rotated when tightening the workpiece, the nut 18 and the movable jaw 4 move forward toward the workpiece W, and the movable jaw 4 moves toward the workpiece W.
Although they are close to each other, there is still a slight gap between the two. This gap needs to be smaller than the amount of fluid pressure movement. This state is the initial state.
As described above, in this initial state, the pressure detection switch 33 and the stroke detection switch 43 are still off. Next, the case where the workpiece W is in the correct set state will be explained. In order to clamp the workpiece, a pressure liquid is supplied from a pressure supply source (not shown) through the liquid guide path 6. Then, due to the pressure of the liquid flowing into the shaft hole housing the large diameter portion 7, the large diameter portion 7 is connected to the drive shaft 5 and the nut 1.
8 and the movable jyo 4, the gap between the workpiece and the movable jyo 4 disappears, and the movable jyo comes into contact with the workpiece. As a result of this advancement of the large diameter portion 7, the rod 41 is pushed toward the plate 13 side against the force of the coil spring 42 and approaches the stroke detection switch 43, so that the stroke detection switch 43 is turned on. When the movable jaw comes into contact with the workpiece and cannot move, the pressure of the fluid flowing into the shaft hole housing the large diameter portion 7 increases, and a force is applied to the movable jaw to clamp the workpiece, and the supplied The liquid also flows into the shaft hole housing the piston 30, and its pressure acts on the fixed jaw 3 via the balance block 8, giving a reaction force. Also, this pressure is the disc spring 3
When the value corresponding to the initial setting value of 2 is exceeded, the piston 30 is pushed toward the plate 13 side against the disc spring 32, so that the piston 30 is activated by the pressure detection switch 3.
3, the pressure detection switch 33 is turned on. That is, in the completely set state, both the pressure detection switch 33 and the stroke detection switch 43 are turned on. Next, the case of the above-mentioned state () will be explained. In this state, the workpiece is being tightened without being set in the vise, which is so-called non-setting tightening. The liquid supplied through the liquid guide path 6 flows into the shaft hole that accommodates the large diameter portion 7, and the pressure causes the large diameter portion 7 to flow into the shaft hole.
moves forward together with the drive shaft 5 and the movable jaw 4.
As a result, the rod 41 is pushed toward the plate 13 against the coil spring 42, and its flange temporarily turns on the stroke detection switch 43. However, since the workpiece W has not been set, the movable jaw 4 moves further forward without resistance, and the large diameter portion 7 also continues to move forward. Then, since the flange of the rod 41 passes the position of the stroke detection switch 43, the stroke detection switch 43 is eventually turned off. After the large diameter portion 7 continues to move forward, it comes into contact with the balance block 8 and stops moving forward. On the other hand, since there is no substantial resistance to the liquid supplied through the liquid guide path 6, most of it initially flows toward the shaft hole housing the large diameter portion 7, and also flows into the shaft hole housing the piston 30. Although some flow flows into the piston 30, the pressure corresponding to the initial setting value of the disc spring 32 is applied to the piston 30.
It will not be enough to affect. However, the fluid pressure supplied when the large diameter portion comes into contact with the balance block 8 exceeds a value corresponding to the initial setting value of the disc spring 32, so the piston 30 is moved against the disc spring 32. Since it is pushed toward the plate 13 side, the piston 30 approaches the pressure detection switch 33 and the pressure detection switch 33 is turned on. That is, in the non-set state, the pressure detection switch 33 is turned on and the stroke detection switch 4 is turned on.
3 is off. Next, the case of the above-mentioned state () will be explained. In this case, even if the movable jaw moves the entire fluid movement amount, it does not come into contact with the workpiece, so the result is exactly the same as in case (). Next, the case of the above-mentioned state () will be explained. In this case, the fluid movement is complete, so the stroke detection switch is turned on.
Since the pressure for tightening is insufficient, sufficient tightening force cannot be obtained and the pressure detection switch remains off. Next, the case of the above-mentioned state () will be explained. In this case, since neither fluid movement nor fluid pressure movement occurs, both the stroke detection switch and the pressure detection switch remain off. By the way, when the on/off signals P and S from the pressure detection switch 33 and the stroke detection switch 43 are processed by a circuit as shown in FIG. 2, the output signal X from the flip-flop is expressed in positive logic as shown in the following table become.

[Table] Therefore, if the configuration is such that, for example, a lamp is turned on by this output signal
The worker can check whether the condition () is present or not by looking at the lamp. In the above embodiment, an example is shown in which a position detection sensor is used as the pressure detection switch, but by using a displacement sensor, it is possible to detect not only the presence or absence of a tightening force but also the magnitude of the tightening force. Furthermore, as an output signal of the detection state, in addition to the electrical signal processing method illustrated in FIG. 2, it is also possible to use a display means such as an air lamp using a fluid switching valve shown in FIG. Furthermore, in addition to displaying, this signal output can be fed back to the control section to be used for various automation control signals.
The above explanation was about tightening the vise, but when releasing the tightening, if the supply from the fluid supply source is cut off and the pressure is lowered at the same time, the force of the coil spring 19 will cause the drive shaft to 5.
moves backward and the movable jaw separates from the workpiece, allowing the workpiece to be removed. At this time, both the stroke detection switch and the pressure detection switch during normal tightening change from the on state to the off state, so that it is also possible to detect the completion state of the tightening release. (Effects) Workers can check whether the tightening condition is correct or defective without directly touching the workpiece.
Tightening work can be performed reliably and without danger.

[Brief explanation of the drawing]

FIG. 1: A cross-sectional side view of an example of a vise equipped with the device of this invention. 2 and 3; a circuit diagram showing an example of a signal processing circuit of the device shown in FIG. 1; FIG. 2...Base, 3...Fixed jaw, 4...Movable jaw, 5...Drive shaft, 6...Liquid guide path, 7...Large diameter section, 8...Balance block, 13...Plate, 18... ...Feed nut, 30...Piston, 3
3... Pressure detection switch, 43... Stroke detection switch, 41... Rod, W... Work.

Claims (1)

[Claims for Utility Model Registration] A fixed jaw integrally formed on the base, and a base shaft hole extending in the tightening direction and slidably and rotatably installed on the base, and at the end on the side of the fixed jaw. A drive shaft having a large diameter part housed in the interior and a screw in its body, and a movable jaw that is operatively connected to the drive shaft via the screw and is constructed on the base so as to be slidable in the tightening direction. and a pressurized fluid supply mechanism to the base shaft hole in which the large-diameter portion is accommodated, a vise provided near the drive shaft to detect movement of the drive shaft in the tightening direction. Stroke detection switch 4
3, and a pressure detection piston 3 housed in the cylinder.
0, an elastic pressing mechanism interposed between the piston and the fixed member, and a pressure detecting switch 33 provided near the piston; and a pressure detecting piston branched from the pressure fluid supply mechanism. A tightening state detection device for a vise comprising a liquid guiding path communicating with a housed cylinder.