JP2000006096A - Work presser device for printed circuit board processing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To completely suck and remove chips generated in a tool insertion hole of a presser member on the lower side of a pressure foot. SOLUTION: When a presser member 24 is pressed against the top surface W1 of a work with a printed circuit board laminated and an air flow by a suction acts the inner space of a pressure foot 20, the outside air flows into a tool insertion hole 30 from air in-flow channels 50, 51. The outlets of the air in-flow channels 50, 51 are disposed in the circumferential direction without clearance, therefore an inflowing air flow evenly-acts the whole periphery of the inner-periphery surface lower edge part of the tool insertion hole 30 evenly, so that no airdrift of the in-flow air is generated. It is thus possible to prevent chips generated by a tool from remaining at the inner surface of the tool insertion hole 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work holding device for a printed circuit board processing machine, and more particularly, to a structure of a holding device for sucking and removing chips generated during processing from a work surface.

[0002]

2. Description of the Related Art As a conventional apparatus, Japanese Patent Laid-Open Publication No.
No. 008, on the lower surface of a pad P (pressing member) provided below the pressure foot as shown in FIG. 8, around the tool insertion hole H, in a direction substantially tangential to the inner peripheral surface of the tool insertion hole H. A plurality of air inflow grooves a facing each other are formed such that their air outlets b are spaced apart in the circumferential direction, and a suction airflow is generated in the pressure foot while the pad P is pressed against the printed circuit board. There is disclosed a device in which air is flown into a pressure foot from an air inflow groove a to suck and remove chips generated by drilling. Japanese Utility Model Registration No. 3044029 discloses that an air inflow groove on the lower surface of a bush provided below a pressure foot is directed toward the center of a tool insertion hole, and is provided between adjacent air inflow grooves in a circumferential direction. Are disclosed.

[0003]

In the above-mentioned apparatus, as shown in FIG. 8 (a), adjacent air inflow grooves a and air inflow grooves a
Part facing the inner surface of the tool insertion hole, ie, the air outlet b
Are provided at intervals in the circumferential direction. When the air sucked from the air inflow groove a by the suction airflow in the pressure foot reaches the lower edge portion of the tool insertion hole H, the air is directed along the hole inner peripheral surface and in a tangential direction to the tool insertion hole H. From the axial direction to the spiral air flow, so that the outlet b of the air inlet groove a in the inner peripheral surface of the lower edge portion of the tool insertion hole H
As shown in FIG. 8 (b), a region c where the air flow from the air inflow groove a on the opposite side of the air inflow direction of the air inflow groove a is less likely to act as shown in FIG. It is easy for chips to collect. Further, since the air inflow groove does not face the tool insertion hole from the tangential direction, such a problem occurs more remarkably. When one hole processing is completed and the next hole processing is performed, the remaining chips are caught between the pressure foot and the periphery of the next processing hole, which causes inconvenience in the pressing operation of the printed circuit board and eventually processing. The accuracy may be reduced.
It is an object of the present invention to ensure that an inflow airflow from the outside acts on chips to suck up chips.
Another object of the present invention is to make the inflow air flow more reliably act on the processing surface.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention presses the pressing member below the pressure foot against the upper surface of the work and inserts the tool into the pressing member by a plurality of air inflow grooves provided on the lower surface of the pressing member. A printed circuit board having an air inflow passage communicating with the hole, and generating suction airflow in the pressure foot, whereby air flows from the air inflow passage into the pressure foot to suck and remove chips generated during processing. In the processing machine, the air inflow groove is formed around the tool insertion hole such that the air outlet of the air inflow groove is arranged without any gap in the circumferential direction with respect to the entire inner peripheral surface of the tool insertion hole. Item 1). In this configuration, when a suction airflow acts on the pressure foot, outside air flows in from the air inflow groove. At this time, since the air outlets of the air inflow grooves are arranged without gaps in the circumferential direction of the tool insertion hole, the air reliably acts on the entire inner peripheral surface of the tool insertion hole. As a result, there is no air pocket where chips remain on the inner peripheral surface, and chips are reliably sucked and removed. Specifically, the tool insertion hole side ends of the adjacent groove side walls of the adjacent air inflow grooves intersect with each other on a cylindrical surface including the tool insertion hole inner surface.

[0005] It is still more convenient to form the upper wall of the air inflow groove on an inclined surface which faces downward toward the tool insertion hole (claim 3). In this configuration, compared to the case where the upper wall is parallel, the flowing air acts so as to blow downward on the processing surface, so that chips can be more reliably prevented from remaining on the processing surface. The holding member is composed of a pair of left and right open / close arms supported by a pressure foot so as to be openable and closable. Each arm has a pair of notches forming a tool insertion hole when the open / close arm is closed. The arm is opened so that the exchange tool can be passed at the time of tool exchange using the vertical movement of the spindle and closed at the time of machining (claim 4). In this configuration,
The opening / closing arm can be opened and closed without using a special driving device, and the device becomes simple.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A spindle unit 1 is a lifting base.
It is clamped between upper and lower walls 9 and 10 of the base 2 and a fastener 15, and is integrally fixed to the elevating base 2. Guide rails 3 are fixed to both sides of the back of the elevating base 2, and the guide rails 3 are a pair of upper and lower guide rails 4 attached to the fixed bed 100 and extending in the left-right direction (only the lower side is shown here.
A pair of left and right guide members 5 that are guided and moved
The guide screw 6 is guided by a vertical guide groove 6 provided on the front surface of the device, and moves vertically by a feed screw shaft 7. Spindle unit 1
, A spindle 8 is rotatably supported. A pair of guide rods 11, 11 is inserted between the walls 9, 10 on both sides of the spindle unit 1 so as to be movable in the vertical direction, and the upper end of the guide rod 11 is a guide bush 16 fixed to the upper wall 10. It protrudes further upward, and a hook portion 14 is provided at the protruding portion. The lower end of the guide rod 11 protrudes below the lower wall 9, and the right and left mounting portions 20 a of the pressure foot 20 are connected. An engaging portion 12 is integrally provided at an intermediate portion between the guide rods 11, 11.
A compression spring 13 is interposed between 2 and the upper wall 10. With the spring force of the spring 13, the hook portion 14 moves the guide bush 1.
6 is urged in the direction of contact with the upper surface, and in the contact state, downward movement of the guide rod 11 with respect to the elevating base 2 is restricted.

The pressure foot 20 is fitted to the tip 1a of the spindle unit 1 so as to be movable in the axial direction (vertical direction). The pressure foot 20
The facet suction pipe 21 is in communication. A dust collector (not shown) is connected to the swarf suction pipe 21, and swarf generated in the pressure foot 20 during processing is suctioned and removed by air suction from the dust collector. Pressure foot 2
0, a tool passing hole 22 is formed in the lower wall, and the inner diameter thereof is large enough to allow the outer diameter portion D of the tool post 61 holding the exchange tool T to pass when the tool is exchanged from below. (FIG. 7). On the back surface of the pressure foot 20, a holding portion 23 is provided. The holding part 23 has an opening / closing arm 2.
A pair of left and right support shafts 25 parallel to the tool axis provided on the base 24a of 4 are rotatably supported. A short arm 26 further extends rearward integrally with each base portion 24a. At the end of each short arm 26, a cam follower (opening / closing operation section) 27 is provided which is supported around the longitudinal axis of the opening / closing arm 24. A spring 28 is interposed between the pair of short arms 26, 26, and biases the pair of opening / closing arms 24 in a closing direction.

At the end of the opening / closing arm 24, there are provided semicircular notches 29 facing each other, and the pair of opening / closing arms 24 are closed by the spring force of the spring 28 so that the tip of the opening / closing arm 24 is closed. In a state where they are in contact with each other, that is, in a state where they are located at the holding position A, the tool insertion hole 30 is formed coaxially with the tool passage hole 22 of the pressure foot 20 by the pair of notches 29 (FIG. 4B). )). The diameter of the tool insertion hole 30 is set slightly larger than the diameter of the tool to be used. As shown in FIGS. 4 and 5, on the lower surface of the tip of each opening / closing arm 24, an air inflow groove 50 is provided in a direction orthogonal to the arm longitudinal direction.
Is provided. Further, an L-shaped step portion 51A is formed around the notch 29 in the longitudinal direction of the arm. This L
The stepped portion 51A forms an air inflow groove 51 similar to the air inflow groove 50 when the arm is closed. As shown in FIG. 4B, when the arm 24 is closed, the adjacent side walls 50a, 51a of the adjacent air inflow grooves 50, 51 are arranged.
Indicates that the end of the tool insertion hole 30 side is exactly the tool insertion hole 3
The air outlets 50c, 51c of the four air inflow grooves 50, 51 are located on the cylindrical surface including the inner surface of the air inlet groove 50 without any gap in the circumferential direction. When flowing through the tool insertion hole 30 through the
There is no so-called stagnation portion where the inflow of air from the air inflow grooves 50 and 51 does not flow in the inner surface portion. Upper wall 50b, 51b of each air inflow groove 50, 51
Is formed on an inclined surface that is inclined downward from the outer peripheral portion toward the tool insertion hole 30. Air inflow grooves 50, 51
Between them, a contact surface 55 with the upper surface of the work W is formed.

The pair of left and right guide members 5 moving in the left-right direction on the lower side are connected to each other by a bearing box member 35 to form a base.
The lower end of the feed screw shaft 7 is rotatably supported by a bearing in the bearing box member 35 (FIG. 3). Bearing cover integrally fixed to bearing box member 35
Below the 37, a pair of operating pins (operating members: cam members) 38 are provided corresponding to the cam followers 27. The operation pin 38 has a position in the front-rear direction of the cam follower 2.
7 is tapered at the lower end so that the cam follower 27 can smoothly engage with the operating pin 38. The left and right distance of the operating pin 38 is
In contrast, the spindle unit 1 is
0 is pressed against the workpiece W (the height position of the spindle unit 1 changes depending on the hole depth during the processing, etc.), and the moving height position P2 from the position to the next hole processing position described later.
And the lower surface of the opening / closing arm 24 reaches a tool changing position P1 (FIG. 7) at a predetermined height higher than the upper end of the shank of the changing tool in the changing tool preparation position. The cam followers 27 are engaged, and the distance between the cam followers 27 is reduced, whereby the spring 2
The pair of opening / closing arms 24 is opened against the force of 8 and is set to the retracted position B (FIG. 4A) outside the tool passage area through which the tool post 61 passes when the tool is changed. ing.

At the time of machining after the tool change, the spindle unit 1 descends from the tool change position P1. At this time, the guide rod 11 is moved by the hook portion 14 by the spring force of the spring 13.
Is in contact with the guide bush 16, the pressure foot 20 and the spindle unit 11 descend while maintaining the relative vertical direction relationship of FIG. Along with this, the cam follower 27 descends from the position p1 where the opening / closing arm 24 has been opened corresponding to the tool change position P1 (FIG. 6), and the engagement with the operating pin 38 is released, whereby the spring The opening / closing arm 24 at the retracted position B is closed by the spring force of 28, the arms are brought into contact with each other, the opening / closing arm 24 is positioned at the holding position A, and a pair of semicircular notches 29 An insertion hole 30 is formed coaxially below the tool passage hole 22. By the subsequent lowering operation of the spindle unit 1, the pressure foot 20 is moved through the opening / closing arm 24 to the table 4
The upper surface F of the work W on which the printed circuit boards are laminated is pressed. The tip of the opening / closing arm 24 is the upper surface W of the workpiece W.
1, an air inflow passage is formed by the air inflow grooves 50 and 51 and the upper surface of the work W. The height position of the cam follower 27 when the pressure foot 20 presses the work (substrate) W is indicated by a position p0 in FIG. When the spindle unit 1 further descends, the guide rod 1
The spindle unit 1 descends relatively to the pressure foot 20 while bending the first spring 13, and the tool T pierces the printed circuit board through the tool passage hole 22 and the tool insertion hole 30 (FIG. 2). .

During machining with the tool T, the work W is pressed near the edge of the machining hole by the opening / closing arm 24, so that the floating of the printed circuit board caused by the lead of the tool T (drill) during machining is suppressed. Thus, inconvenience such as occurrence of return can be avoided. During processing, the suction airflow from the dust collector acts on the space inside the pressure foot 20, whereby air flows from the air inflow passage through the tool insertion hole 30 into the internal space of the pressure foot 20. For chips generated inside the tool insertion hole 30 due to the drilling of the tool T, the air inflow groove 50 forming the air inflow passage,
Since the upper walls 50b and 51b of the 51 are inclined downward, the inflow air blows toward the upper surface W1 of the work W, so that the air effectively acts to blow off the chips, while the four air inflow grooves are provided. 50, 51 outlets 50c, 51
Since c faces the entire inner periphery of the lower edge of the tool insertion hole 30, the flowing air acts on the entire circumference of the inner peripheral surface of the tool insertion hole, so that chips are formed on the lower edge of the tool insertion hole 30. There is no remaining snowdrift. As a result, the chips are reliably removed by suction.

When the next drilling operation is performed, when the spindle unit 1 is raised and the guide bush 16 is hooked on the hook portion 14 of the guide rod 11 to reach a slightly raised height position P2, the opening / closing arm is opened. Since the lower end of the drum 24 is separated from the upper surface W1 of the work W (the state shown in FIG. 1), it moves to the next processing hole position in that state. At the movement height position P2 for the movement during the machining, the height relationship between the cam follower 27 and the operation pin 38 is set so that the cam follower 27 does not engage with the operation pin 38 ( At the position p2) in FIG. 6, the opening / closing arm 24 remains closed. During this movement, no chips remain at the lower edge of the tool insertion hole 30, so that they do not fall near the next machining hole, and the pressure foot suppresses such dropped chips during the next hole machining. Since this can be avoided, the processing accuracy is not reduced.

Next, when the tool is changed, the tool change position P1 is separated from the height position P0 at which the spindle unit 1 is drilled by a large distance above the moving height position P2.
(Fig. 7). Then, during the ascent, the cam follower 24 starts to engage with the operating pin 38, the cam followers 24 move toward each other, and the opening / closing arm 24 moves to the retreat position B. As a result, a passage area through which the exchange tool T can pass is formed between the end portions of the opening / closing arm 24. Then, the used tool T is returned to the empty tool post 61 of the tool magazine 60 located coaxially with the spindle unit 1, and the tool post 61 holding the tool T to be used next is coaxially aligned with the spindle unit 1. Then, the tool post 61 is pushed up from below, and the tool T is mounted on the spindle 8 through the tool passage hole 22 of the pressure foot 7 from the passage area between the front ends of the opening / closing arm 24. In the embodiment of the present application, the holding member is described as an open / close type. However, the present invention is not limited to this, and is also applicable to a holding bush as shown in FIG. it can.

[0014]

As described above, according to the present invention, since the air inflow groove faces the entire inner periphery of the tool insertion hole, the air reliably acts on the entire inner peripheral surface of the lower edge of the tool insertion hole. Then, there is no air pocket where chips remain on the inner peripheral surface, and chips are reliably removed by suction. As a result, chips are prevented from dropping at the time of the next hole machining, and such a problem that such chips are pressed by the pressure foot and the machining accuracy is reduced can be eliminated. In addition, the upper surface of the air inflow groove is sloped downward, and the sucked air blows toward the upper surface of the work, so that it works to blow off the chips on the upper surface of the work, and the remaining chips are more effectively prevented. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a front view of a spindle unit of a printed circuit board processing machine.

FIG. 2 is a side view of FIG. 1, showing a state during perforation.

FIG. 3 is a view as viewed in a direction III in FIG. 2;

FIG. 4 is an enlarged view of a tip end portion of the opening / closing arm in FIG. 3, (a) showing an open state, and (b) showing a closed state.

FIG. 5 is an enlarged view of a portion S in FIG. 2;

FIG. 6 is a view taken along the line VI in FIG. 2, showing a height relationship between a cam follower and an operating pin.

FIG. 7 is an explanatory diagram at the time of tool replacement.

FIG. 8A is a view of a conventional pressing member viewed from a lower surface side,
(B) is an operation view of (a).

[Description of Signs] 20 Pressure foot 24 Opening / closing arm (holding member) 30 Tool insertion hole 50, 51 Air inflow groove 50a, 51a Groove side wall of air circulation groove 50b, 51b Upper wall of air inflow groove W Work

Claims (4)

[Claims] An air inflow passage communicating with a tool insertion hole of a pressing member is formed by a plurality of air inflow grooves formed in a lower surface of a pressing member by pressing a pressing member on a lower side of the pressure foot to a work upper surface. In a printed circuit board processing machine in which air is caused to flow into the pressure foot from the air inflow passage to suck and remove chips generated during processing by generating a suction airflow in the airflow passage, the air outlet groove has a tool insertion hole. A work holding device for a printed circuit board processing machine, wherein an air inflow groove is formed around a tool insertion hole so as to be arranged in a circumferential direction with no gap with respect to the entire inner peripheral surface of the work. 2. The printed circuit board processing machine according to claim 1, wherein the end portions of the adjacent groove side walls of the adjacent air inflow grooves on the tool insertion hole side cross each other on a cylindrical surface including the inner surface of the tool insertion hole. Work holding device. 3. The work holding device for a printed circuit board processing machine according to claim 1, wherein an upper wall of the air inflow groove is formed on a slope inclined downward toward the tool insertion hole. 4. The holding member comprises a pair of left and right opening and closing arms supported by a pressure foot so as to be openable and closable, and each arm has a pair of notches forming a tool insertion hole when the opening and closing arm is closed. The opening / closing arm is formed so as to be able to pass an exchange tool at the time of tool change using a vertical movement of a spindle, and to be closed at the time of machining. Work holding device for printed circuit board processing machine.