JPS6113012A - Expansion type clamp apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Scope of Application of the Invention The present invention relates to a hollow plastic expansion rivet, also known as an expansion rivet or blind rivet, and a plastic material that moves axially into the rivet to expand the rivet. This invention relates to an expansion type fastening device consisting of a pin.

(Known Example) The aforementioned tightening device is disclosed in, for example, U.S. Pat. No. 4.222,30.
It is described in Specification No. 4. This patent shows a blind rivet formed by injection molding a plastic material. This rivet has a female member molded around a male member. The female member has a flexible tubular wall and a flange at its upper end, the wall forming a step within the axial bore at its upper end, and the wall having a plurality of elongated holes therein. The male member has a shank movable axially within the axial bore relative to the tubular wall, an enlarged head at one end thereof in intimate engagement with the lower end of the female member, and the other end projecting from the upper end of the female member. It has a protrusion at. The protrusion is shaped to be gripped by a tool to pull the shaft axially through the shaft hole. The shank has a series of edge pawls each forming a shoulder facing the lower end such that tension causes the perforated flexible tubular wall to collapse and radially expand, with each successive pawl causing a corresponding shoulder to form a shoulder on the step. The shoulder is engaged, and this engagement maintains the radially expanded tubular wall of the female member and prevents axial movement of the male member toward the lower end of the female member.

In the above-mentioned tightening device, the male member and the female member are integrally molded together during manufacturing using a two-shot molding process, and when tightening, it is difficult to disassemble the components of the tightening device due to problems such as gaps. cannot be decomposed either. Furthermore, during its manufacture, the male and female members are provided with interlocking serrations so that a large force is initially required to move the pin axially into the rivet throat before the rivet wall expands. Become. Furthermore, the pin has a part that projects from the rivet, which part must be cut off with a cutting tool after setting the tightening device. In particular, because conventional rivets and pins are molded together by a two-shot molding process, attempts to form brake recesses or grooves in the pins are not possible because the grooves are filled by the plastic material used to form the rivet.

[Summary of the invention]

SUMMARY OF THE INVENTION The object of the present invention is to obtain an expansion type clamping device which solves the above-mentioned problems.

The inflatable fastening device of the present invention consists of two separately molded plastic parts, a female member which is an inflatable hollow plastic rivet, and a male member which is a plastic drive pin. The rivet has a flange at one end and a grooved shank that can be inserted into a hole in the workpieces to be joined. The rivet has a through hole and small diameter portions at both ends thereof. An annular groove is formed in the small diameter portion of the rivet near the flange. The drive pin has a head at one end and a shank extending through the hole in the rivet. The drive pin shaft portion has a large diameter cylindrical portion and an adjacent small diameter cylindrical portion. A recess is formed between the two cylindrical portions.

The large diameter tubular portion has a serrated gripping member and a constriction adjacent the head. The drive pin is pulled axially into the rivet hole by the tool such that the head of the drive pin engages the insertion end of the rivet shank and the wall of the rivet shank expands outwardly.

The tool-engaging protrusion of the pin is broken at a recessed portion formed in the pin shaft. A small diameter hole portion near the insertion end of the rivet engages a constriction in the shank adjacent the head of the pin, causing the pinning vents to be temporarily held together prior to use. The serrated gripping member of the large diameter portion of the pin, which is not initially engaged with the large diameter hole portion of the rivet, comes to engage with the groove of the small diameter hole portion of the flange portion of the rivet upon insertion of the pin.

The tightening device of the present invention has various advantages over conventional ones. For example, a small diameter portion at the end of the rivet engages a fin in the shank adjacent to the head of the pin, temporarily holding the rivet and pin together prior to use and preventing undue movement of each.

The pin also has a smooth shank and a serrated gripping member that does not initially engage any part of the vent hole, making the initial insertion of the pin into the rivet hole less conventional. It does not require much force. When the pin is pulled axially relative to the rivet, the gripping member eventually engages the annular groove in the small diameter hole portion of the rivet, resulting in a forceful connection between the rivet and the pin. Additionally, the shank of the pin is recessed so that the tool-engaging protrusion can be separated by subsequent application of axial force by the tool after the rivet has completed expansion, eliminating the need for additional cutting tools. do not. The tightening device of the present invention is inexpensive and easy to use.

[Embodiments of the invention]

The present invention will be explained in detail below with reference to the drawings.

1 to 8, reference numeral 10 designates an inflatable clamping device of the present invention, which clamps two workpieces 16.
18 together with the workpieces 16.1
It can be inserted into the hole 12.14 in 8. FIG. 6 shows the clamping device 10 inserted into the hole 12.14 of the workpiece 16.1B but not yet expanded, and FIG. 7 shows the expanded condition. The inflatable fastening device 10 consists of two members: a female member, an inflatable hollow plastic rivet 20, and a female member inserted into the rivet and moved axially relative to the rivet by a tool (not shown). It comprises an associated male member, plastic drive pin 22, for expanding the rivet from the condition of FIG. 6 to the condition of FIG.

The rivet 20 and pin 22 are made of relatively hard plastic.
For example, it is made of nylon, acetal plastic material, etc., and formed separately by an injection molding process.

The rivet 20 having an end flange and an insertion end has a cylindrical shaft 24 , a flange 26 , and a cylindrical hole 28 passing through the flange 26 and the shaft 24 . This hole 28 has a hole portion 30 and a small diameter hole portion 3 near the flange of the rivet 20.
2. An annular groove 32A is formed in the small diameter hole portion 32, and a protrusion 32B is formed between the grooves. A small diameter portion 21 is formed near the insertion end of the rivet 20. The shank 24 has two elongated holes 34 extending through the shank wall portion and defining two flexible wall portions 36 which are folded outwardly during expansion of the rivet 20 as shown in FIGS. has. Each flexible wall section 36 has a shoulder 37. Hole 28
The inner small diameter portion 21 fits into the constriction 52 in the shank 40 of the drive pin 22, thereby tightening the rivet 20 and the drive pin 22.
are temporarily engaged.

The thickened portion adjacent to the small diameter portion 21 serves to reinforce the shaft and prevent outward bending of the shaft when the pin 22 is pulled axially.

The drive pin 22 has a cylindrical pin shank 40 with a head 42 at the end, an intermediate portion 44, and one end of said intermediate portion 44 such that the excess protruding end of the pin shank is ruptured by axial force. It consists of a rupture recess 46 formed in the hole and a smooth cylindrical tool engaging protrusion 48 near the insertion end. The intermediate portion 44 of the shaft 40 includes a plurality of serrated gripping members 50 defining axially spaced annular sharp edges.
has. The aforementioned constriction 52 is provided between the intermediate portion 44 of the shaft portion 40 and its head. Intermediate portion 44 frictionally engages small diameter portion 21 within rivet 20 to engage rivet 20 and pin 22 together prior to use, as shown in FIG.

The diameter of the intermediate portion 44 and its grip member 50 opposite the hole portion 30 is smaller than the inner diameter of the hole portion 30 of the rivet 20, but larger than the small diameter hole portion 32. Grip member 50 is engaged with protrusion 32B in small diameter bore portion 32 after axially moving the pin and expanding rivet 20 to permanently engage the pin vents together. The diameter of the gripping member 50 is equal to the diameter of the pin shank 40, but the diameter of the tool engaging protrusion 48 is tapered to fit into the small diameter hole portion 32. However, hole portion 30 does not engage grip member 50. A tear recess 46 is formed on the upper shank of the grip member 50.

Rivet 20 and drive pin 22 are manufactured separately.

The pin 22 is manually or mechanically inserted into the hole 2 of the rivet 20.
The small diameter portion 21 in the hole 28 frictionally engages the constriction 52 in the pin 22, and the head 42 is brought into contact with the insertion end surface 39 of the rivet 20.

As shown in FIG. 6, the clamping device 1o is inserted in this pre-assembled state into the hole 12.14 in the adjacent workpiece 16.18 so that the flange 26 of the rivet abuts the surface of the workpiece 16. As shown in FIG. 6, the tool engaging protrusion 48 of the pin shaft 40 protrudes outward from the flange end of the hole 28 of the vent 20, and the tightening device 10 is attached to a tool (not shown) for expanding the rivet. ). This tool consists of two relatively movable parts, one of which moves the flange 26 of the rivet onto the workpiece 1.
6, the other member simultaneously grips the tool-engaging projection 48 of the pin 22 and pulls the rivet 20 axially within the hole 28, upwardly in FIG. Movement of the pin causes the pin head 42 to move over the insertion end surface 39 of the rivet shank 24, causing the flexible wall portion 36 to fold as shown in FIGS. .18 is the flange 26 and the folded wall section 36
sandwiched between. The pin 22 moves from the position shown in FIG.
When moved axially as shown, the shank 40 moves outwardly from the pet hole 28, the grip member 50 engages the wall of the small diameter hole portion 32, and the recess 46 engages the top surface of the rivet flange 26. be in a line position. In this state, pin 22
can no longer move in any axial direction within the bore 28 of the rivet 20. Further axial pulling of the pin 22 by the tool causes the tool engaging protrusion 48 to move in the area of the recess 46 as shown in FIG. Since the rivet 20 and pin 22 are tightly engaged with each other, the rivet and pin are separated from the intermediate portion 44 of the pin under pressure.
It is made of plastic that can flow for a long time, so the first
The wall of the small diameter hole portion 32 of the pin 20 is inserted between the grip members 50 of the pin so that they are not separated from each other,
Second, the insertion end surface 39 of the shaft portion 24 of the rivet 20 is
It enters into the constriction 52 on the lower side of the head 42 of No. 2, further strengthening the connection between the rivet and the pin.

9 to 14, 310 designates an inflatable clamping device according to another embodiment of the invention, which clamping device 310 is inserted into the holes 12.14 of two workpieces 16.18, It is for permanently joining the workpieces 16, 18 together. Figure 12 shows workpiece 16
．． 13 and 14 show the tightening device 310 inserted into the hole 12.14 of 18 but not yet expanded. FIGS. 13 and 14 show the expanded condition. The inflatable tightening device 310 includes an inflatable hollow plastic rivet 320 which is inserted into the rivet and moved axially relative to the rivet by a tool (not shown) to move the rivet from the state shown in FIG. 12 to the state shown in FIG. It has an associated plastic drive pin 322 for inflation to the state shown. Rivet 320 and pin 3
22 is made of a relatively hard plastic, such as nylon, and is separately formed by an injection molding process.

A cylindrical shaft portion 24 having a flange 26 at one end of the rivet 320, and a hole 2 passing through the flange 26 and the shaft portion 24.
8. This hole 28 has a large diameter hole portion 3o and a small diameter hole portion 32 near the end of the shaft portion 24 near the flange. An annular groove 32A is formed in the hole portion 32, and a protrusion 32B is formed between the grooves. A small diameter portion 21 is formed in the hole 28 near the insertion end of the rivet 20. Shaft part 2
4 extends through the wall of the shank and collapses under external force during expansion of the rivet 320 as shown in FIGS. 13 and 14.
It has three elongated holes 34 defining two flexible wall sections 36. Each flexible wall section 36 has a shoulder 37.

The drive pin 322 is the same as the pin 22 of the previous embodiment.

The intermediate portion 44 of the shaft 40 has a plurality of serrated gripping members 50 forming axially spaced annular sharp edges. Constriction 52 in pin 322 engages reduced diameter portion 21 in rivet 320 to engage rivet 320 and pin 322 together prior to use, as shown in FIG. The gripping member 50 is attached to the protrusion 32 of the small diameter bore portion 32 after axially moving the pin to expand the rivet 320 to permanently couple the pin head.
B is engaged. The gripping member is the same diameter as the pin shank 40, but the tool engaging protrusion 48 is of a smaller diameter and is progressively press fit into the smaller diameter hole portion 32.

[Brief explanation of the drawing]

Fig. 1 is a front view of the gluing pin of the device of the present invention, Fig. 2 is a side view thereof, Fig. 3 is a plan view thereof, Fig. 4 is a front view of the drive pin of the device of the present invention, and Fig. 5 is its side view. A plan view, FIG. 6 is a sectional view of the rivet and pin connected to the workpiece, FIG. 7 is a sectional view of the main part of the workpiece with the workpiece tightened, FIG. 8 is a bottom view, and FIG. 9 10 is a rear view thereof, FIG. 11 is a plan view thereof, FIG. 12 is a sectional view of the rivet and pin connected to a workpiece, and FIG. FIG. 13 is a cross-sectional view of the main part with the workpiece tightened, and FIG. 14 is a bottom view thereof. 10.310...Inflatable tightening device, 12.14.28
．． 34...hole, 16.18...workpiece, 20,320...hollow plastic rivet, 2
DESCRIPTION OF SYMBOLS 1... Small diameter part, 22.322... Plastic drive pin, 24... Cylindrical shaft part, 26... Flange, 3
0.32...hole part, 32A...groove, 32B...
...Protrusion part, 36...Flexible wall part, 39...Insertion end surface, 40...Shaft part, 42...Head, 44...Middle part, 46...Indentation, 48... - Tool engagement protrusion, 50...grip member, 52...constriction. , Eu#σノf rectangle A L℃1 , uQj- FIG 12 Fl(y, 14

Claims (13)

[Claims] (1) Flange 26 formed at one end and axial through hole 2
8, a rivet 20 having a hole 34 formed in a wall portion, and a small diameter hole portion 32 at one end of the through hole 28; inserted into the through hole 28 from an initial position to a set position in order to expand the rivet 20; a drive pin 22, said drive pin 22 having an intermediate portion 44 and an intermediate portion 44;
a tool engaging protrusion 48 at one end and said intermediate portion 4;
4 and the recess 46 formed between the tool engaging protrusion 48
and a head 42 formed at the other end of the intermediate portion 44 for engaging the other end of the rivet 20, and the rivet 20 and the pin 22 have an engagement mechanism that engages each other in their initial positions. an intermediate portion 44 of the pin 22 does not engage the rivet 20 when the pin 22 is in the initial position and engages the hole 28 when the pin 22 is moved axially to its set position;
the head 42 of the pin 22 acts on the expansion of the rivet 20 to maintain the pin 22 in the set position;
1. An expansion-type tightening device characterized by maintaining 0 in an expanded state. (2) The engagement mechanism is a constriction 52 on the intermediate portion 44 of the pin 22 for receiving the small diameter portion 21 in the hole 28 of the rivet 20. Expandable tightening device. (3) The inflatable tightening device according to claim 1 or 2, wherein the engaging portion on the intermediate portion 44 of the pin 22 is a serrated grip member 50. (4) Small diameter hole portion 3 in the hole 28 of the rivet 20
3. The expansion type tightening device according to claim 3, wherein 2 has a groove 32A. (5) Flange 26, rivet shaft 24, and this shaft 24
a rivet 20 having a through hole 28 and a hole 34 formed in the wall portion of the shank; a head 42 at one end thereof, which causes the rivet 20 to expand when engaged with the rivet shank 24; The driving pin 22 has a shaft portion 40 that can be inserted into the through hole 28 in the axial direction from an initial position to a set position, and the through hole 28 has a small diameter hole portion 32 at one end near the flange 26. and has a small diameter portion 21 at the other end, and the shaft portion 40 of the drive pin 22 is formed between an intermediate portion 44, a tool engaging protrusion 48, and between the intermediate portion 44 and the tool engaging protrusion 48. a concavity 46 and a constriction 52 in the intermediate portion 44 adjacent to the head 42, the small diameter portion 21 in the hole 28 and the constriction 52 in the pin shank 40 engaging each other in their initial positions; and the intermediate portion 44 of the pin 22 does not engage the hole portion 32 of the rivet 20 when the pin 22 is in the initial position and engages the hole 28 when the pin 22 is moved axially to its set position. An expansion fastening device characterized in that it has a serrated gripping member 50 that engages a small diameter hole portion 32 therein to maintain said pin 22 in said set position and said rivet 20 in an expanded condition. (6) The expansion type tightening device according to claim 5, wherein the small diameter hole portion 32 within the hole 28 has a groove 32A. (7) The shaft portion 24, the flange 26 formed at one end of the shaft portion 24, the axial through hole 28, the small diameter hole portion 32 formed in the hole 28 near one end of the shaft portion 24, and the wall of the shaft portion a rivet 20 having a hole 34 formed in a portion 36 for allowing said wall portion 36 to expand outwardly;
and a drive pin 22 having a pin shaft portion 40 that can be inserted into the hole 28 and a head 42 near one end of the pin shaft portion 40 that engages with one end of the shaft portion 24 of the rivet 20. The pin shaft portion 40 has an intermediate portion 44 and a tool engaging protrusion 4.
8 and a recess 46 for allowing the tool engaging protrusion 48 to be separated from the intermediate portion 44 by a tool formed between the intermediate portion 44 and the tool engaging protrusion 48; The wall portion 36 of the rivet 20 is moved axially by a tool from its initial position to a set position relative to the rivet 20 to cause the wall portion 36 of the rivet 20 to expand outwardly, causing the tool engaging protrusion 48 of the pin shank 40 to the rivet 20 and the pin 22 have an engagement mechanism that engages with each other in their initial positions; A small diameter hole portion 32 within said hole 28 which does not engage the wall portion 36 of the rivet 20 when the front pin 22 is moved axially by said tool to its set position.
a workpiece 16, 18 by means of a tool, characterized in that it has an engaging portion for engaging the pin 22 in the set position and the rivet 20 in an expanded state;
an expansion-type clamping device set within the bores 12, 14; (8) The pin shaft portion 40 for the engagement mechanism to receive the small diameter portion 21 in the hole 28 of the rivet 20.
8. An inflatable clamping device according to claim 7, wherein the constriction 52 is a constriction 52 on said intermediate portion 44 of. (9) The expansion type tightening device according to claim 7 or 8, wherein the engaging portion on the intermediate portion 44 of the pin shaft portion 40 is a serrated grip member 50. (10) The expansion type fastening device according to claim 9, wherein the small diameter hole portion 32 in the hole 28 of the rivet 20 has a groove 32A. (11) A shaft portion 24, a flange 26 formed at one end of this shaft portion 24, an axial through hole 28, a small diameter portion 21 and a small diameter hole portion 32 formed in the hole 28 near both ends of the shaft portion 24. a rivet 20 having a hole 34 formed in a wall portion 36 of the shaft portion for allowing the wall portion 36 to expand outward; a pin shaft portion 40 insertable into the hole 28; and the rivet 20. a drive pin 22 having a head 42 near one end of the pin shaft 40 that engages with the other end of the shaft 24; the pin shaft 40 has an intermediate portion 44;
a tool-engaging protrusion 48 of a smaller diameter; and a recess 46 for allowing the tool-engaging protrusion 48 to be separated from the intermediate portion 44 by a tool formed between the intermediate portion 44 and the tool-engaging protrusion 48. , a constriction 52 in the intermediate portion 44 that engages a small diameter portion 21 in the bore 28 to maintain the drive pin 22 in its initial position, and the drive pin 22 is set from its initial position by a tool. axially moved into position relative to the rivet 20 to cause the wall portion 36 of the rivet 20 to expand outwardly and cause the tool engaging protrusion 48 of the pin shank 40 to protrude from the hole 28; The intermediate portion 44 of the pin shank 40 does not engage the wall portion 36 of the rivet 20 when the pin 22 is in the initial position, but remains in the hole when the pin 22 is axially moved by the tool to its set position. Small diameter hole portion 32 within 28
a workpiece 16, 18 by means of a tool, characterized in that it has an engaging portion for engaging the pin 22 in the set position and the rivet 20 in an expanded state;
an expansion-type clamping device set within the bores 12, 14; (12) The inflatable fastening device according to claim 11, wherein the engaging portion on the intermediate portion of the pin is a serrated grip member. (13) The expansion type fastening device according to claim 11 or 12, wherein a small diameter hole portion in the hole of the rivet has a groove.