TWI739061B - Vacuum suction arm and collet - Google Patents

Abstract

The vacuum suction arm system is equipped with a hollow cylindrical arm spindle (11), a ring-shaped 1st O-ring (21) and a 2nd O-ring (23), and a hollow cylindrical collet (31), the arm spindle (11) ) Has a first inner circumferential groove (15) and a second inner circumferential groove (17) arranged parallel to each other on the inner circumferential surface, the first O-ring (21) and the second O-ring (23) are They are respectively fitted into the first inner circumferential surface groove (15) and the second inner circumferential surface groove (17), and are arranged so that a part of them invades from the inner circumferential surface toward the central axis of the arm spindle (11), the collet (31) ) Is a ring-shaped first outer circumferential surface groove and a second outer circumferential surface groove arranged parallel to each other on the outer circumferential surface. When the insertion part of the upper part of the collet (31) is inserted into the lower part of the arm spindle (11), the first O-ring (21) and the second O-ring (23) are provided by the first outer circumferential groove and the second outer circumferential groove, respectively. The surface groove is maintained.

Description

Vacuum suction arm and collet

The present invention relates to a vacuum suction arm and a collet provided at the front end of the vacuum suction arm. The vacuum suction arm is a component of a precision machining device that vacuum-suctions and operates fine components such as electronic parts.

A precision machining device such as an assembly machine for assembling electronic parts. The tip of the precision machining device is equipped with a vacuum chuck mechanism (vacuum suction arm) such as a vacuum camera for vacuuming the object to be operated. The following operations can be performed, that is, the vacuum suction of the object to be operated by making the hollow part of the vacuum suction arm into a negative pressure, and the desorption of the object to be operated by becoming a positive pressure, and the installation In any part. The nozzle head (collet) set at the front end of the vacuum suction arm is precisely designed to match the object to be operated, and it is a consumable that wears and breaks with repeated use. In addition, according to the type of object to be handled, the tip of the nozzle at the front end of the collet or collet must be appropriately replaced. Therefore, at least one of the vacuum suction arm and the collet generally has a mechanism suitable for replacement that temporarily fixes the collet to the vacuum suction arm.

Therefore, the structure that has been proposed is to insert the upper part of the collet 34 into the lower part of the collet insertion hole provided at the front end of the arm of the vacuum suction arm. The fixing screw screwed into the side of the mounting part is locked (refer to Patent Document 1). That is, the collet described in Patent Document 1 includes an insertion portion to be inserted into the upper part of the collet insertion hole, that is, an insertion portion, a large-diameter portion having a larger diameter than the insertion portion, and a portion extending downward from the large-diameter portion The tip of the nozzle with a tapered tip. A vacuum through hole is formed in the collet. The vacuum through hole penetrates the upper and lower sides and serves as a suction hole communicating with the collet insertion hole.

It is also proposed that a slit is provided in the insertion portion to be inserted into the insertion hole of the collet to give elasticity to the collet, and the slit has the center axis direction as the depth direction. The slit is a U-shaped cut from the upper end of the insertion portion toward the downward direction, and the shape of the insertion portion is a bifurcated spring-like structure. The diameter of the insertion part of the collet is designed to be slightly larger than the diameter of the collet insertion hole. When the insertion part of the collet is inserted into the collet insertion hole, the part divided by the slit is slightly closer to the slit side and the central axis side, This reduces the diameter so that the collet can be inserted into the collet insertion hole. After insertion, the rebound force caused by the elasticity of the part partitioned by the slit to return to its original shape will act outward, so that the collet is tightly fixed to the collet insertion hole. The advantage is that the insertion and removal of the collet can be performed in a one-touch manner by applying a certain force.

However, in this conventional technique, both the through hole that penetrates the central axis direction of the collet formed in a minute shape and the slit formed in the insertion portion of the smaller shape must be processed with high accuracy. The slit provided in the insertion part, because part of it is continuous with the through hole related to the suction and desorption function of the operated object, may affect the operated object according to the width of the slit or the length of the central axis of the slit. The adsorption function of the substance has an impact. In addition, even the fixing force to the main body of the precision machining device may cause problems. Therefore, the processing of through-holes and slits requires sophisticated precision processing technology, and there has been a problem that the collet itself, which is a replacement part, becomes expensive. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 2000-114282 A

The present invention was developed focusing on the above-mentioned problems, and its purpose is to provide a vacuum suction arm which can insert and remove the collet at the front end in a one-touch manner without causing compression cracks of the O-ring to strengthen the collet. The holding force of the vacuum suction arm, and provides the collet of the constituent member of the vacuum suction arm.

In order to achieve the above object, the first aspect of the present invention is based on a vacuum suction arm, the vacuum suction arm system is provided with (a) arm spindle, (b) first and second O-ring (O-ring ), and (c) collet, (a) The arm main shaft is formed into a first cylindrical shape surrounding the vacuum suction hole, and the first and second inner circumferential grooves are provided parallel to and separated from each other on the inner circumferential surface of the first cylindrical shape. (b) The first and second O-rings are to fit a part of each into the grooves of the first and second inner peripheral surfaces, and let the remaining part of each protrude from the inner peripheral surface toward the central axis of the vacuum suction hole , (c) The collet is a second cylindrical shape formed in a concave-convex shape. The second cylindrical shape is provided with a retaining convex portion at the tip. The retaining convex portion has an outer diameter smaller than that of the inner peripheral surface. The retaining surface of the diameter defines the outer peripheral surface, and has a wide groove continuous to the retaining convex portion and smaller in diameter than the retaining convex portion. At the bottom of the wide groove, there are first and second parallel to each other. Grooves on the outer peripheral surface. In the vacuum suction arm of the first aspect, when the upper part of the collet is inserted into the lower part of the arm spindle, the first and second O-rings are held by the first and second outer circumferential grooves, respectively.

The second aspect of the present invention relates to a collet inserted into the arm body. The arm body is formed in a first cylindrical shape surrounding the vacuum suction hole, and the first and second inner circumferential surfaces are formed on the inner circumferential surface of the first cylindrical shape. The grooves are arranged in parallel and separated from each other. The collet is a second cylindrical shape with a concave-convex shape. The second cylindrical shape is provided with a retaining convex portion at the tip. The retaining convex portion has a diameter larger than the inner peripheral surface. A retaining surface with a smaller outer diameter defines the outer peripheral surface, and has a wide groove continuous with the retaining convex portion and having a smaller diameter than the retaining convex portion. The collet of the second aspect is that the bottom of the wide groove is provided with first and second outer peripheral grooves arranged parallel to each other. As with the vacuum suction arm of the first aspect, in the first and second inner circumferential grooves, a part of each of the first and second O-rings is fitted, and the remaining part of each is removed from the inner circumferential surface. Protruding toward the center axis of the vacuum suction hole. In this state, when the upper part of the collet is inserted into the lower part of the arm spindle, the first and second O-rings are held by the first and second outer circumferential grooves, respectively .

According to the aspect of the present invention, a vacuum suction arm can be provided, which can insert and pull out the collet at the front end in a one-touch manner, without causing compression cracks of the O-ring, and can strengthen the holding force of the collet, and provide the A collet that is a component of the vacuum suction arm.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the following drawings, the same or similar parts are given the same or similar symbols. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the plane size, the size ratio of each component, etc. are different from reality. Therefore, the specific thickness, size, size, etc., should be judged more diversified with reference to the technical ideas that can be understood based on the following description. In addition, of course, even if the drawings are mutually different, the dimensional relationships and ratios are different from each other.

In addition, the embodiment of the present invention shown below is an example of an apparatus for embodying the technical idea of the present invention. The technical idea of the present invention is not limited to the material, shape, structure, arrangement, etc. of its constituent parts. As described below. The technical idea of the present invention is not limited to the content described in the embodiments of the present invention, and various modifications can be implemented within the technical scope defined by the claims described in the scope of the patent application.

(Implementation form)

As shown in Figure 1 (a) and (b), the vacuum suction arm of the embodiment of the present invention is provided with: an arm spindle 11 formed in a first cylindrical shape and a collet 31, the collet 31 is The insertion part is inserted through the lower part of the vacuum suction hole 13 in the cylinder axis direction of the arm main shaft 11. As shown in Fig. 1(c), in the lower part of the inner wall of the arm main shaft 11, an annular first inner peripheral surface groove (outer diameter side annular groove) 15 and a second inner peripheral surface groove ( The outer-diameter side annular grooves) 17 are carved parallel to each other in the form of cylindrical grooves. A first O-ring (O-ring) 21 and a second O-ring 23 made of an elastic body are respectively arranged on the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17. In FIG. 1(c), although the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17 are illustrated as square grooves, they can also be used with the first O-ring 21 and the second O-ring 23. The dovetail groove of the prevention effect constitutes the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17. In addition, although illustration is omitted in FIG. 1(c), it is of course possible to give R chamfering (curved surface processing) to the corners of the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17.

As shown in FIG. 1(c), the collet 31 is formed in a hollow cylindrical shape having a through hole 33 penetrating the central axis direction. As shown in FIG. 1(c), the collet 31 is provided with a wide groove 35 so as to surround the outer peripheral surface of the upper insertion part. Regarding the width of the wide groove 35, the first O-ring 21 and the second O-ring 23 can be accommodated in the wide groove 35 when the insertion portion of the collet 31 is inserted into the arm spindle 11. A stopper 37 is provided on the outer peripheral surface of the insertion portion lower than the wide groove 35. The stopper 37 is an annular holding convex portion, and constitutes a large-diameter portion having a larger diameter than the insertion portion of the collet 31. As the large-diameter stopper 37, when the insertion portion of the collet 31 is inserted toward the arm spindle 11, it is buffered and held by the stopper receiving portion 19 provided at the inner edge of the opening at the lower end of the arm spindle 11 . The stopper 37 has a function of determining the insertion depth of the insertion portion of the collet 31 at the time of insertion. In Fig. 1(c), the stopper 37 and the stopper receiving portion 19 are continuous and the same ring shape, but in order to further have the function of determining the rotation position, they can also be placed on the circumference of the collet 31 and the arm spindle 11 Part of it is set intermittently.

FIG. 5 shows the collet 31 of the second cylindrical reference example formed in a diameter smaller than the diameter of the inner peripheral surface of the vacuum suction hole 13. On the outer peripheral surface of the insertion portion of the upper part of the collet 31 of the reference example, an annular first inner diameter side annular groove (first outer peripheral surface groove) OG ₁₂ and a second inner diameter side annular groove ( The second outer circumferential surface grooves) OG _{11 are} arranged parallel to each other. FIG. 2 is an enlarged view of a part corresponding to the _{first outer circumferential surface groove OG 12} of the collet 31 shown in FIG. 5. Generally speaking, in the case of a rod seal, only the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17 are provided in the form of cylindrical grooves on the inner wall of the arm main shaft 11 in the case of the piston seal (piston seal), and the collet is in the outer peripheral surface 31, only the outer circumferential surface of the first groove 2 OG ₁₂ and the second outer circumferential surface groove OG ₁₁ arranged in the form of a cylindrical groove. However, in the vacuum suction arm of the embodiment, it is characterized in that a cylindrical groove is provided on the outer peripheral surface of the collet 31 so as to face the first inner peripheral surface groove 15 of the arm main shaft 11. 1 Outer circumferential groove OG ₁₂ , and a second outer circumferential groove OG is provided in the form of a cylindrical groove on the outer circumferential surface of the collet 31 so as to face the second inner circumferential groove 17 of the arm main shaft 11 ₁₁ .

In FIG. 1( c ), the first O-ring 21 is fitted into the first inner circumferential groove 15, and the second O-ring 23 is fitted into the second inner circumferential groove 17. The 1st O-ring 21 and the 2nd O-ring 23 are solid torus tire bodies, respectively, and are formed by rotating the circular cross section shown in FIG. 1(c). A part of the 1st O-ring 21 protrudes from the first inner circumferential surface groove 15 and constitutes a holding convex portion that is bent from the position of the inner circumferential surface of the arm main shaft 11 toward the central axis of the vacuum suction hole 13. Similarly, a part of the second O-ring 23 protrudes from the second inner peripheral groove 17 and constitutes a holding convex portion that is bent from the position of the inner peripheral surface of the arm main shaft 11 toward the central axis of the vacuum suction hole 13. In the cross-sectional view of Fig. 1(c), although the shapes of the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17 are U-shaped, as long as the first O-ring 21 and the second O-ring can be combined 23 are fitted separately, and other shapes such as U-shape and V-shape are okay. The arm spindle 11, the first O-ring 21, and the second O-ring 23 constitute a collet holding portion (11, 21, 23).

In FIG. 2, d ₀ represents the smallest diameter of the collet 31 located at the bottom of the first outer circumferential groove OG ₁₂ and the second outer circumferential groove OG _{11 ; d 1} represents, in the wide groove 35, The diameter of the collet 31 on the surface where the first outer circumferential surface groove OG _{12 is not formed.} In FIG. 2, the outer diameter d _{3 of the} guide portion represents the diameter of the collet 31 located on the holding surface S _{2 where the wide groove 35 is not formed.} Holding surface S ₂ is held and inserted into the inclined surface S ₃ S ₁ surrounded by the inclined surface. Holding the inclined surface S ₃ of the first inclined surface constituting the outer peripheral surface of the trench groove OG V ₁₂ and is continuous with the holding surface S _2; S ₁ are inserted into the inclined surface S ₃ and the inclined surface opposed to the holding and the holding surfaces S ₂ consecutive .

For the first O-ring 21 fixed to the first inner circumferential groove 15 of the arm spindle 11 and the second O-ring 23 fixed to the second inner circumferential groove 17 to reduce the insertion pressure when inserting the collet 31 The insertion angle θ _i formed by the insertion inclined surface S ₁ and the inner wall surface S _{4 of} the through hole 33 is preferably set in the range of 22 to 33°, and more preferably in the range of 24.5 to 25.5°. The insertion angle θ _i is a chamfer, and when the collet 31 is inserted into the arm spindle 11, this chamfer is equivalent to a guide angle for inserting the tip of the collet 31 into the first O-ring 21 and the second O-ring 23.

In the vacuum suction arm of the embodiment, the purpose of the first O-ring 21 and the second O-ring 23 is not only to ensure the airtightness of the vacuum seal, etc., but also to obtain the holding force for holding the collet 31 on the arm spindle 11 In order to achieve insertion and removal durability and ease of insertion and removal, the inner diameter of the first O-ring 21 and the second O-ring 23 in the state where the collet 31 has not been inserted, the first outer circumferential surface groove OG _{12 of the collet 31} And the minimum diameter d _{0 of the} second outer circumferential groove OG ₁₁ is increased, and the compression rate ε _{1 of the} first O-ring 21 and the compression rate ε _{2 of the second} O-ring 23 are selected to be 17 to 19%, respectively.

。 同樣的，第2O型環23的壓縮率ε₂ ，是將第2O型環23之壓縮量δ₂ 除以第2O型環23的線徑D₂ 而得之數值：

。 如圖9所示般，在氟系橡膠系O型環的情況，若將壓縮率ε₁ ,ε₂ 設定為30%以上，筒夾31朝向臂主軸11的插入變困難。The compression rate ε ₁ , ε ₂ of the 1st O-ring 21 and the 2nd O-ring 23 depends on the hardness of the 1st O-ring 21 and the 2nd O-ring 23, but if the hardness (the hardness of the rubber hardness tester) If) is 70~90 degrees, set it to 15~25%. The compression rate ε ₁ of the first O-ring 21 is a value _{obtained by dividing the compression δ 1} of the first O-ring 21 by the wire diameter (thickness) D _{1 of the first} O-ring 21:

. Similarly, the compression rate ε ₂ of the 2nd O-ring 23 is the value _{obtained by dividing the compression δ 2} of the 2nd O-ring 23 by the wire diameter D _{2 of the 2nd} O-ring 23:

. As shown in FIG. 9, in the case of a fluorine-based rubber-based O-ring, if the compression rates ε ₁ and ε _{2 are} set to 30% or more, the insertion of the collet 31 toward the arm spindle 11 becomes difficult.

In the case of a fluorine-based rubber O-ring, if it is purely for the purpose of ensuring sealing performance, the compression should be 8% on the right. As a result of try and error, the inventors of the present invention have learned that, as shown in FIG. 9, if the compression ratio of the O-ring exceeds 30%, the assembly performance when the collet 31 is inserted into the arm spindle 11 is deteriorated. . After further conducting various experiments, it was found that if the compression rate of the structure shown in Figure 1 exceeds 41%, the compression cracks of the O-ring as shown in Figure 9 will occur and cause the O-ring to break. Therefore, the inventors of the present invention, based on the knowledge shown in FIG. 9, in order to minimize the compression and permanent deformation of the O-ring and ensure the assemblability when the collet 31 is inserted into the arm spindle 11, the structure shown in FIG. The compression rate ε _{1 of the} first O-ring 21 and the compression rate ε _{2 of the second} O-ring 23 are selected to be 17 to 19%, respectively.

In the design of general rod seals and piston seals, the insertion angle θ _i should be selected in the range of 15-30°. In the vacuum suction arm of the embodiment, for the first O-ring 21 and the second O-ring 23 fixed to the arm main shaft 15, in order to facilitate the insertion of the collet 31, the smallest diameter of the front end of the collet 31 is made larger than that of the first outer circumference. The minimum diameter d _{0 of the} surface groove OG ₁₂ etc. is smaller. As described above, because the compression rate of the O-ring ε ₁ = ε _{2 is} selected to be 17 to 19%, in the vacuum suction arm of the embodiment, the insertion angle θ _{i is} selected to be in the range of 24.5 to 25.5°. as the inclined surface so that the insertion of the chamfered surface S ₁ exhibit good shoehorn (guide surface) of the action.

Embodiment of the vacuum suction arm, when the arm is obtained based on the main shaft 11 of collet 31 is inserted into the plug durability and easiness object plug, the length of the collet 31 of the holding surface S _2, i.e., to maintain the length L _h1 , The wire diameter D _{1 of the} first O-ring 21 and the wire diameter D _{2 of the second} O-ring 23 are selected as 1/3 to 1/4 of each. For example, if the wire diameter D _{1 of the 1st} O-ring 21 is 1 mm, the holding length L _h1 can be selected as 0.225 mm. If the retention length L _{h1 is} greater than the diameter of the O-ring D ₁ , _{1/3 of D 2,} it will be difficult for the arm spindle 11 to insert and remove the collet 31, and the O-ring will be durable. Sex becomes worse. On the other hand, if the holding length L _{h1 is} smaller than 1/4 of the wire diameters D ₁ and D ₂ of the O-ring, the holding force desired when the collet 31 is inserted into the arm spindle 11 becomes impossible.

In order to achieve the durability of insertion and removal of the O-ring, the ease of insertion and removal of the collet 31 of the arm spindle 11, and in order to achieve the desired retention force when the collet 31 is inserted into the arm spindle 11, the reason shown in Fig. 2 The holding angle θ _h formed by the holding inclined surface S ₃ and the inner wall surface S _{4 of} the through hole 33 is preferably selected in the range of 42 to 48°, and more preferably in the range of 44 to 46°. If the holding angle θ _{h is} smaller than 42°, the holding force desired when the collet 31 is inserted into the arm spindle 11 cannot be achieved. On the other hand, if the holding angle θ _{h is} larger than 48°, it becomes difficult to insert and remove the collet 31 with respect to the arm spindle 11, and the insertion and removal durability of the O-ring deteriorates.

In the vacuum suction arm of the embodiment shown in Figs. 1(a) and (b), the lower side of the collet 31 is provided with a suction nozzle tip whose outer diameter at the front end is a cone-shaped hollow. In the inside of the tip of the suction nozzle, a through hole 33 that penetrates the collet 31 is provided from the front end toward the upper side so as to be continuous with the vacuum suction hole 13. The lower part of the arm spindle 11 functions as a "collet insertion hole". When the upper part of the collet 31 is inserted into the lower part of the arm spindle 11, the first O-ring 21 and the second O-ring 23 are held by the first outer circumferential groove OG ₁₂ and the second outer circumferential groove OG _{11, respectively.} , And achieve the desired retention.

As shown in Figs. 1(a) and (b), at the upper end of the arm main shaft 11, a vacuum piping adapter 51 continuous to the vacuum suction hole 13 is fixed. With the arm spindle 11 inserted into the upper portion of the collet 31, the air is sucked by a vacuum pump through the joint 51, thereby making the vacuum suction hole 13 and the through hole 33 a negative pressure, and the pressure on the collet 31 The front part absorbs electronic parts. In a state where the electronic component is sucked, the vacuum suction hole 13 and the through hole 33 are made to have a positive pressure, whereby the sucked electronic component is detached from the front end portion of the collet 31.

The groove depths of the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17 provided on the arm main shaft 11 shown in Fig. 1(c) are t ₁₂ and t ₁₁ respectively as shown in Fig. 4, The widths of the grooves are W ₁₂ and W _{11, respectively} . As shown in FIG. 1(c), a first O-ring 21 and a second O-ring 23 are fitted into the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17, respectively. In order for the 1st O-ring 21 to function appropriately, the groove depth t ₁₂ and the width W ₁₂ of the first inner circumferential surface groove 15 are designed to ensure that the compression ratio of the 1st O-ring 21 is ε ₁ =17. _{The compression amount δ 1} of the 1st O-ring 21 after ~19% and the insertion pressure are taken into consideration, and an appropriate clearance amount for the compression amount δ _{1 is ensured.} Similarly, in order for the 2nd O-ring 23 to function appropriately, the groove depth t ₁₁ and the width W ₁₁ of the second inner circumferential surface groove 17 are designed to ensure the compression rate ε of the 2nd O-ring 23 _{2 = 17~19% and the compression δ 2} of the 2nd O-ring 23 after taking into account the insertion pressure, and ensure proper clearance for the compression δ _{2. Further selected, the first outer circumferential groove OG 12} on the outer circumferential surface of the collet 31 facing the first inner circumferential groove 15 and the second outer circumferential groove OG 12 facing the second inner circumferential groove 17 _{The minimum diameter d 0} of the collet 31 measured at the bottom of the two grooves of the groove OG ₁₁ . The depths of the groove bottoms of the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17 provided on the arm main shaft 11 are based on the fact that the outer diameter expansion rate of the first O-ring 21 and the second O-ring 23 becomes 0 ~3% for selection.

As described above, in the vacuum suction arm of the embodiment, the depth t ₁₂ , t ₁₁ and the width W ₁₂ , W ₁₁ of the groove are adjusted so that the collet 31 is not obstructed when the collet 31 is inserted into the arm spindle 11 The insertion action of 31 does not allow the first O-ring 21 and the second O-ring 23 to fall off from the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17.

。 同樣的，第2O型環23的壓縮率n₂ ，可使用第2O型環23的壓縮量δ₂ 、線徑D₂ 而用下式表示：

。Regarding the widths W ₁₂ and W ₁₁ of the 1st O-ring 21 and the 2nd O-ring 23, if the rubber hardness of the 1st O-ring 21 and the 2nd O-ring 23 is about 70 to 90 degrees, then the 1O-ring The filling rate n ₁ and n ₂ of the ring 21 and the 2nd O-ring 23 are set so that they become 70 to 80%. In addition, the compression rate n _{1 of the 1st} O-ring 21 can be expressed by the following formula using _{the compression δ 1} and the wire diameter D _{1 of the 1st O-ring 21:}

. Similarly, the compression rate n _{2 of the} 2nd O-ring 23 can be expressed by the following formula using _{the compression δ 2} and the wire diameter D _{2 of the 2nd O-ring 23:}

.

In Fig. 1(c), the minimum diameter d _{0 of the} collet 31 is selected so that the inner diameter expansion rate of the 1st O-ring 21 and the 2nd O-ring 23 becomes 1~5%, the minimum diameter d _{0 The value of is the inner diameter after taking into account the compression amount δ 1} , δ ₂ when the 1st O-ring 21 and the 2nd O-ring 23 are fixed, or for the fixing of the 1st O-ring 21 and the 2nd O-ring 23 When the compression amount δ ₁ , δ _{2 is} taken into consideration, the internal diameter is added with a certain clearance diameter δ.

In the vacuum suction arm of the reference example shown in FIGS. 3 and 5, d ₁ represents the surface in the wide groove 35 where the first outer circumferential surface groove OG ₁₂ and the second outer circumferential surface groove OG ₁₁ are not formed For the diameter of the collet 31, the outer diameter of the guide part is set to d ₃ =d ₁ . When the guide portions is set to an outer diameter d _3, the diameter of the surface ₁₁ and the wide groove 35 of the outer peripheral surface of the first groove is not formed OG outer circumferential surface ₁₂ and the second groove OG equal, although insertion is facilitated However, the desired holding force when the spindle 11 inserts the collet 31 cannot be achieved, which is not ideal.

Therefore, it is preferable to be configured such that, like the vacuum suction arm of the embodiment shown in FIG. 1(c), the outer diameter of the guide portion is set to d ₃ > d ₁ , which serves as a retaining protrusion from the center axis toward the centrifugal direction. The upper surface of the portion is provided with a holding surface S ₂ , whereby the fixing force in the state where the arm spindle 11 is inserted into the insertion portion of the collet 31 is strengthened. The positions of the first outer circumferential surface groove OG ₁₂ and the second outer circumferential surface groove OG ₁₁ in the direction of the cylinder axis, as long as the first and second OG on the arm spindle It suffices that the ring is kept in a fixed position. By engraving the wide groove 35, the first outer circumferential surface groove OG ₁₂ , and the second outer circumferential surface groove OG ₁₁ on the outer circumferential surface of the insertion part of the collet 31, the first O-shaped The relative positions of the ring 21 and the 2nd O-ring 23 are accurately positioned. In FIG. 5, the cross-sections of the first outer circumferential surface groove OG ₁₂ and the second outer circumferential surface groove OG _{11 are} preferably V-shaped with the holding angle θ _h in the range of 42 to 48°. The cross-sectional shape of the first outer circumferential surface groove OG ₁₂ and the second outer circumferential surface groove OG ₁₁ , as in the comparative example shown in FIGS. 7 and 10, is formed by holding the inclined surface S _3p and the inner wall surface of the through hole 33 When the holding angle θ _{hp formed by S 4} is 90° U-shaped or ㄈ-shaped, the ease of insertion and removal of the collet 31 with respect to the arm spindle 11 deteriorates, and the insertion and removal durability of the O-ring deteriorates, so Not ideal. In the normal design of the collet 31 of the comparative example shown in FIG. 10, the compression ratios ε ₁ and ε ₂ of the O-ring are set to be smaller than 17 to 19%. Thus, in the cartridge clip Comparative Example 31, the inner diameter of the O-ring can be greater than in the case shown in FIG. 2, generally by a collet inserted into the inclined surface S _1p 31 and the inner wall surface of the through hole 33 is formed by S ₄ The insertion angle θ _{ip is} set to about 15°, which is smaller than the insertion angle θ _i shown in FIG. 2.

( Insertion action of collet ) Using Fig. 1(c), Fig. 2 and Fig. 4, etc., the insertion action of the insertion part of the collet 31 of the arm spindle 11 will be explained. _{When inserting the insertion portion of the collet 31 into the arm main shaft 11, first insert the inclined surface S 1} of the front end of the collet 31 on the 2nd O-ring 23 fitted in the groove 17 of the second inner peripheral surface of the arm main shaft 11 Then, the upper surface of the holding convex portion continuous to the insertion inclined surface S ₁ , that is, the holding surface S _{2 is} brought into contact. The upper surface of the retaining convex portion having the guide portion outer diameter d ₃ , that is, the retaining surface S _{2 is} continuously pressed from the 2nd O-ring 23 toward the central axis of the arm spindle 11, and at the same time, the insertion portion of the collet 31 As the insertion progresses, when the holding surface S _{2 of the} collet 31 is out of contact with the second O-ring 23, the second O-ring 23 becomes in contact with the wide groove 35 of the collet 31.

Next, when the upper surface of the retaining convex portion of the collet 31, that is, the retaining surface S ₂ is in contact with the first O-ring 21 fitted in the groove 15 of the first inner peripheral surface, it is in contact with the second O-ring 23 In the same situation, the holding surface S ₂ is pressed from the first O-ring 21 toward the central axis of the arm main shaft 11. As the insertion action progresses, when the contact between the 1st O-ring 21 and the holding surface S _{2 having the outer diameter d 3} of the guide portion is released, the 1st O-ring 21 becomes the holding inclined surface S _{3 of the wide groove 35} touch. The stopper 37 provided on the collet 31 is at a position held by the stopper receiver 19 provided on the arm main shaft 11, so that further insertion becomes impossible. In this position, the first O-ring 21 is held by the first outer circumferential groove OG ₁₂ , and the first outer circumferential groove OG ₁₂ is pressed from the first O-ring 21 toward the central axis of the arm spindle 11. At this time, the second O-ring 23 is held by the second outer circumferential groove OG ₁₁ , and the second outer circumferential groove OG ₁₁ is pressed from the second O-ring 23 toward the central axis of the arm main shaft 11.

， 藉此，可將筒夾31的插入部對於臂主軸11之插入壓力減小。或者，對於圖4所示之第2內周面溝槽17的溝槽寬度W₁₁ ，將第1內周面溝槽15之溝槽寬度W₁₂ 設定成：

， 藉此可將筒夾31之插入部對於臂主軸11之插入壓力減小。The compression rate ε _{1 of the} first O-ring 21 is _{different from the compression rate ε 2 of the second O-ring 23. For the groove depth t 12} of the first inner circumferential groove 15 shown in FIG. 4, the second inner circumferential The groove depth t _{11 of the} face groove 17 is set to:

As a result, the insertion pressure of the insertion portion of the collet 31 with respect to the arm spindle 11 can be reduced. Alternatively, for the second groove width of the inner circumferential face of the trench 17 as shown in FIG. 4 W _11, the inner circumferential surface of the first groove width W ₁₂ of the groove 15 is set to:

, Thereby, the insertion pressure of the insertion portion of the collet 31 with respect to the arm spindle 11 can be reduced.

的方式，來調整式(3)、(4)所記載之第1O型環21的壓縮量δ₁ 及線徑D₁ 、以及第2O型環23的壓縮量δ₂ 及線徑D₂ 等。總之，筒夾31的插入部對於臂主軸11之插入動作，可如以上所說明般以單觸方式進行。關於將筒夾31從臂主軸11拔出的動作，能用與插入動作相反的機制而以單觸方式進行。In addition, by setting the filling rate n _{1 of the} first O-ring 21 to be larger than the filling rate n _{2 of the} second O-ring 23, the insertion pressure of the insertion portion of the collet 31 with respect to the arm spindle 11 can also be reduced. That is, it can also become the following formula:

_{To adjust the compression amount δ 1} and wire diameter D ₁ of the first O-ring 21 and the compression amount δ ₂ and wire diameter D _{2 of the} second O-ring 23 described in equations (3) and (4). In short, the insertion operation of the insertion portion of the collet 31 with respect to the arm spindle 11 can be performed in a one-touch manner as described above. The operation of pulling out the collet 31 from the arm spindle 11 can be performed in a one-touch manner by a mechanism opposite to the insertion operation.

As aforesaid, since the collet diameter of the upper portion 31 of the set to be d _3> d _1, and has a holding length L _h1 toward the centrifugal direction of the central axis of the holding protrusions, and a holding length L _h1 selected as an O-ring The diameter of the wire diameter D ₁ , D ₂ is 1/3~1/4. When the insertion part of the collet 31 is inserted into the arm spindle 11, the insertion pressure will become a size suitable for insertion. Moreover, as shown in Fig. 1(c), the _{upper surface of the retaining convex portion having the guide portion outer diameter d 3} provided in the insertion portion of the collet 31, that is, the retaining surface S ₂ , serves as a A guide for smooth insertion after contact with the 2nd O-ring 23. Moreover, the wide groove 35 with the diameter d ₁ of the stepped shape is defined by the holding surface S ₂ and the holding inclined surface S ₃ continuous to the holding surface S ₂ , and the holding surface S ₂ and the second O type with the _{holding length L h1 can be realized} The smooth insertion action after the ring 23 touches. If the wide groove 35 with a diameter d ₁ is not provided, in the insertion operation of the collet 31, after the first outer circumferential surface groove OG ₁₂ contacts the second O-ring 23, the outer circumference of the _{guide portion outer diameter d 3} into continuous contact with the surface of 2O-ring 23, compared to the diameter d _1, by more pressing from 2O-ring 23, the insertion operation can not smoothly progress. For the same reason, the wide groove 35 is important in order to realize the smooth pulling-out action of the collet 31.

當使用具有相同標稱直徑之第1及第2O型環的情況，比起圖4的情況，是相當於真空抽吸孔13之直徑變大的構造。在圖6所示的構造，比起圖1(c)所示的構造，第1O型環21及第2O型環23的內徑側是朝向真空抽吸孔13之中心軸方向更顯著的突出。 ( Comparative Example ) The vacuum suction arm of the comparative example of the embodiment of the present invention will be described using FIGS. 6 and 7. In FIG. 6, the depths of the first inner circumferential surface groove 15 and the second inner circumferential surface groove 17 of _{the arm main shaft 11 are respectively t 22} and t ₂₁ , which are shallower than the arm main shaft 11 in Fig. 4.

When the first and second O-rings having the same nominal diameter are used, compared to the case of FIG. 4, it is equivalent to a structure in which the diameter of the vacuum suction hole 13 becomes larger. In the structure shown in FIG. 6, compared to the structure shown in FIG. 1(c), the inner diameter sides of the first O-ring 21 and the second O-ring 23 protrude more prominently toward the center axis of the vacuum suction hole 13 .

。The structure of the collet 31 of the vacuum suction arm of the comparative example shown in Fig. 7 has a _{U-shaped groove with a holding angle θ hp} of 90°, and does not have: the implementation shown in Fig. 1(c) A wide groove 35 like a collet 31 of a vacuum suction arm. Figure 7 d ₀ indicates that the smallest diameter of the collet 31 located on the bottom surface of the first inner diameter side annular groove OG ₂₂ and the second inner diameter side annular groove OG _{21 corresponds to the first O-ring The compression amounts δ 1} and δ _{2 of the} 21 and the 2nd O-ring 23 when they are fixed are the values of the inner diameter after taking into account, so they are the same as the minimum diameter d ₀ shown in FIG. 2. _{The outer diameter d 2} of the insertion portion in FIG. 7 represents the diameter of the outer peripheral surface of the insertion portion of the collet 31 where the first inner diameter side annular groove OG ₂₂ and the second inner diameter side annular groove OG _{21 are not formed, which is} It is larger than the wide groove diameter (outer diameter of the insertion portion) d _{1 in Fig. 2 but smaller than the diameter d 3} of the upper part of the collet 31,

.

求出，t_inner 的值，是將設置於臂主軸11側之第1內周面溝槽15或第2內周面溝槽17的深度t₂₂ ,t₂₁ 、第1O型環21或第2O型環23之固定時的壓縮量δ₁ ,δ₂ 納入考慮來決定。具有插入部外徑d₂ 之插入部的外周面，在筒夾31的插入部之插入時，是與第1O型環21及第2O型環23接觸的面積最大的部分。在圖7中，圖2中之具有導引部外徑d₃ 的保持用凸部並不存在。當使用與圖2所示者相同之第1O型環21及第2O型環23的情況，在圖7中的插入部外徑d₂ ，是比圖2中之與第1O型環21及第2O型環23接觸的面積最大之外周面的插入部外徑d₁ 更大，會發生第1O型環21及第2O型環23更容易從第1內周面溝槽15及第2內周面溝槽17脫落的問題。此外，因為相當於圖2中之具有導引部外徑d₃ 的保持用凸部的部分並不存在，縱使能將筒夾31插入，也會發生容易脫落的問題。The groove depth t of the first inner diameter side annular groove OG ₂₂ and the second inner diameter side annular groove OG ₂₁ can be determined by the following formula:

Calculate, _{the value of t inner is the depth t 22} , t ₂₁ , 1st O-ring 21 or 2O of the first inner circumferential groove 15 or the second inner circumferential groove 17 provided on the side of the arm main shaft 11 _{The compression amount δ 1} and δ ₂ when the ring 23 is fixed are taken into consideration and determined. The outer peripheral surface of the insertion part having the outer diameter d ₂ of the insertion part is the part that has the largest contact area with the first O-ring 21 and the second O-ring 23 when the insertion part of the collet 31 is inserted. In Fig. 7, the retaining convex portion _{having the outer diameter d 3} of the guide portion in Fig. 2 does not exist. When using the first O-ring 21 and the second O-ring 23 that are the same as those shown in FIG. ₂ , the outer diameter d 2 of the insertion portion in FIG. The 2O-ring 23 has the largest contact area. The outer diameter d ₁ of the insertion portion of the outer peripheral surface is larger. It will happen that the first O-ring 21 and the second O-ring 23 are easier to pass from the first inner peripheral groove 15 and the second inner peripheral. The problem of the face groove 17 falling off. In addition, because the portion corresponding to _{the retaining convex portion having the outer diameter d 3} of the guide portion in FIG. 2 does not exist, even if the collet 31 can be inserted, the problem of easy falling off occurs.

Regarding the materials of the 1st O-ring 21 and the 2nd O-ring 23 in Figure 1(b) and (c), part or all of the fluorine-based rubber using fluororesin as the raw material is based on the A specified in the JIS standard (JISK6253) The indentation hardness (hardness) of the rubber hardness tester is 70 to 90 degrees, and it has a moderate hardness, high workability, and a small surface friction coefficient. It is particularly suitable. Other materials used for O-rings, such as natural rubber, or synthetic rubbers such as polybutadiene, nitrile, chloroprene, etc. can also be used, but when using materials other than fluorine rubber, the first O type In the case of the ring 21 and the second O-ring 23, the setting ranges of the _{insertion angle θ i} , the holding angle θ _h , the holding length L _{h1, etc. are narrowed.} In addition, when a material other than fluorine-based rubber is used, in general, there is a tendency that the fixing force in the state where the collet 31 is inserted into the arm spindle 11 cannot be sufficiently obtained, which is not ideal. If it is the case where the fixing force is reduced when the collet 31 is inserted into the arm spindle 11, as long as it has the strength and rubber elasticity that can withstand use and processing, the material of the 1st O-ring 21 and the 2nd O-ring 23 is no matter which one is used. Either way.

Although the material of the arm spindle 11 and the collet 31 in Figure 1 (a) and (b), (c) is mainly metal, as long as it has the strength to withstand use and processing, for example, glass fiber or carbon fiber can be added. Fiber Reinforced Plastic (FRP), a composite material with a metal material inside and plastic injection molding around it, etc.

When an O-ring is used to hold the collet 31 in the arm main shaft 11, there is a contradictory relationship between the improvement of the holding force and the ease of insertion and removal of the collet 31. In addition, there is a contradictory relationship between the holding force for holding the collet 31 to the arm spindle 11 and the insertion and removal durability of the O-ring. As shown in Figure 1, Figure 2 and Figure 4, the vacuum suction arm of the embodiment can realize the insertion and removal of the collet 31 with a lower insertion pressure, so the collet 31 can be used for the arm spindle 11 in a one-touch manner. The insertion and removal is performed, and the holding force for holding the collet 31 to the arm main shaft 11 can be increased to a desired value. In addition, the component member of the vacuum suction arm, that is, the collet 31 as a replacement member, only needs to be processed on the outer peripheral surface, which does not affect the through hole 13 at all, and the insertion and removal durability of the O-ring is also improved. Thereby, the processing of the collet 31 is facilitated by using a lathe or the like, and therefore, an inexpensive and highly durable vacuum suction arm can be realized.

( Other Embodiments ) Although the present invention is described using the above-mentioned embodiments, it should be understood that the statements and drawings constituting a part of this disclosure are not intended to limit the present invention. Based on this disclosure, those with ordinary knowledge in the technical field should understand that there are various alternative embodiments, embodiments, and application techniques.

In addition, part of the individual technical ideas explained in the above embodiment may be combined with each other as appropriate. In this way, the present invention naturally includes various embodiments that are not described herein. Therefore, the technical scope of the present invention can be properly interpreted based on the above description, and is only defined by the invention specific matters in the scope of the patent application.

11‧‧‧Arm spindle 13‧‧‧Vacuum suction hole 15‧‧‧The first inner circumferential groove 17‧‧‧The second inner circumferential groove 19‧‧‧Brake member receiving part 21‧‧‧No. 1O O-ring 23‧‧‧The 2nd O-ring 31‧‧‧Collet 33‧‧‧Through hole 35‧‧‧Wide groove 37‧‧‧Brake part 51‧‧‧ Adapter for vacuum _{piping OG 11} ‧‧‧Second outer circumferential groove OG ₁₂ ‧‧‧First outer circumferential groove OG ₂₁ ‧‧‧Second inner diameter side annular groove OG ₂₂ ‧‧‧First Ring groove on the inner diameter side

Fig. 1(a) is a front view of the vacuum suction arm of the embodiment of the present invention, Fig. 1(b) is a cross-sectional view when viewed from the AA direction of Fig. 1(a), and Fig. 1(c) is Fig. 1( b) An enlarged view of part B.

Fig. 2 is a cross-sectional view showing an enlarged part of the collet shown in Fig. 1(c).

Fig. 3 is a cross-sectional view corresponding to Fig. 2 showing an enlarged part of the collet of the vacuum suction arm of the reference example of the present invention.

FIG. 4 is an enlarged cross-sectional view of the arm spindle 11 of FIG. 1(c) after being extracted.

FIG. 5 is a cross-sectional view showing a part of the collet of the vacuum suction arm corresponding to the reference example of FIG. 3 in a wider range.

Fig. 6 is an enlarged cross-sectional view of the lower part of the arm spindle of the comparative example.

Fig. 7 is an enlarged cross-sectional view of the upper part of the tip of the suction nozzle of the comparative example.

Figure 8 is a bird's-eye view of Figure 1(a).

Fig. 9 is an explanatory diagram of problems and effects when the compression ratio of the O-ring changes.

Fig. 10 is an enlarged cross-sectional view showing a part of the collet of the vacuum suction arm of the comparative example.

11‧‧‧Arm spindle

13‧‧‧Vacuum suction hole

15‧‧‧The first inner circumferential groove

17‧‧‧Second inner circumferential groove

19‧‧‧Brake member receiving part

21‧‧‧The 1st O-ring (O-ring)

23‧‧‧The 2nd O-ring (O-ring)

31‧‧‧Collet

33‧‧‧Through hole

35‧‧‧Wide groove

37‧‧‧Brake parts

51‧‧‧Adapter for vacuum piping

Claims (2)

A vacuum suction arm, characterized in that it is provided with an arm spindle, first and second O-rings, and a collet, The arm spindle is formed in a first cylindrical shape surrounding the vacuum suction hole, and first and second inner circumferential grooves are provided in parallel and separated from each other on the inner circumferential surface of the first cylindrical shape. The first and second O-rings are to fit a part of each into the first and second inner circumferential grooves, and let the remaining part of each from the inner circumferential surface toward the central axis of the vacuum suction hole protrude, The collet is a second cylindrical shape formed in a concave-convex shape, the second cylindrical shape is provided with a retaining convex portion at the tip, and the retaining convex portion has a diameter smaller than the diameter of the inner peripheral surface The retaining surface of the outer diameter defines the outer peripheral surface, and has a wide groove continuous with the aforementioned retaining convex portion and having a smaller diameter than the aforementioned retaining convex portion. At the bottom of the aforementioned wide groove, there is a first parallel arranged in parallel to each other. 1 and 2 outer circumferential grooves, When the upper part is inserted into the lower part of the arm spindle, the first and second O-rings are held by the first and second outer circumferential grooves, respectively. A collet is a collet inserted into an arm body. The arm body is formed in a first cylindrical shape surrounding a vacuum suction hole, and the first and second inner circumferential grooves are formed on the inner circumferential surface of the first cylindrical Are arranged in parallel and separated from each other. The collet is a second cylindrical shape formed in a concave-convex shape, and the second cylindrical shape is provided with a retaining convex portion at the front end. A holding surface with an outer diameter with a smaller diameter defines the outer peripheral surface, and has a wide groove continuous with the holding convex portion and having a smaller diameter than the holding convex portion, which is characterized by: The bottom of the wide groove is provided with first and second outer peripheral grooves arranged parallel to each other, In the first and second inner circumferential surface grooves, a part of each of the first and second O-rings is fitted, and the remaining part of each of the first and second O-rings is directed from the inner circumferential surface to the vacuum The central axis of the suction hole protrudes. In this state, when the upper part is inserted into the lower part of the arm main shaft, the first and second O-rings are held by the first and second outer circumferential grooves, respectively.

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