JP5697549B2 - Automatic tool changer - Google Patents

Description

  The present invention relates to an automatic tool changer applied to various industrial robots.

  Conventionally, the connection method of an automatic tool changer (Auto Tool Changer) applied to various industrial robots has a lock pin that can withstand a large load applied during connection while maintaining the connection state of the automatic tool changer. Two types of connection methods are known: a connection method using a cam mechanism and a connection method using a ball and a flange.

  An automatic tool changer that employs a coupling method using a lock pin and a cam mechanism is configured so that the cam mechanism can follow the wear, so that the amount of gap that can occur in the coupling part (the distance between the robot adapter and the tool adapter due to the moment load) The distance when opening is made as small as possible. On the other hand, in order to secure the strength that can withstand a large load applied when the automatic tool changer is connected, it is necessary to increase the thickness of the portion that holds the lock pin. It has a demerit that the thickness increases.

  On the other hand, an automatic tool changer that employs a connection method using a ball and a flange has a high strength that can withstand the load applied when the ball and the flange are connected, and keeps the thickness of the entire automatic tool changer in a connected state small. be able to. On the other hand, the automatic tool changer has a demerit that the gap amount tends to increase due to wear of the balls, and the balls need to be changed frequently in order to maintain a stable connection state. .

  Here, among the above-described two types of connection methods, as an automatic tool changer employing a connection method using a lock pin and a cam mechanism, the one disclosed in Patent Document 1 below is known. FIG. 6 shows an example of a conventional automatic tool changer that employs a coupling method using a lock pin and a cam mechanism. The automatic tool changer 201 shown in FIG. 6 includes a male member 204 having a projection 240 formed at one end 204a and an operation unit such as a robot arm attached to the other end 204b, and a welding tool at one end 205a. And a female member 205 having a hole 250 into which the protrusion 240 can be inserted.

  In the initial state shown in FIG. 6A, the automatic tool changer 201 is connected in a state where the positions of the outer peripheral portions of the male member 204 and the female member 205 are aligned with each other. Air is supplied from the arm or the like to the cylinder housing chamber 244 of the male member 204, and the pressure of the air causes the air cylinder 245 and the piston 247 to move in the direction of the arrow shown in white in FIG. ing. Along with this movement, the pair of elastic members 248 are biased (compressed) in the direction of the arrow.

  Next, in FIG. 6B, the male member 204 and the male member 204 are placed in the space on the elastic member 248 side of the cylinder housing chamber 244 in a state where the protrusion 240 of the male member 204 is inserted into the hole 250 of the female member 205. By supplying the air for connecting the female member 205, the internal pressure of the space increases, and the directions of the arrows shown in white in FIG. 6A for each elastic member 248 as a safety mechanism. Restoring force acts in the opposite direction. That is, the air cylinder 245 and the piston 247 move in the opposite directions according to the internal pressure of the space and the restoring force of each elastic member 248. Along with this movement, the cam mechanism 246 rotates in the direction indicated by the thick line in FIG. 6B, whereby the cam mechanism 246 and the lock pin 251 are engaged. This engagement restricts the cam mechanism 246 from moving in the direction opposite to the insertion direction of the protrusion 240 into the hole 250, and the connection between the male member 204 and the female member 205 is completed.

  In the conventional automatic tool changer 201, as shown in FIG. 7, in the female member 205, the driving force from the cam mechanism 246 (open arrow shown in FIG. 7) is the thick line in FIG. As shown by the arrows, the structure is such that it is locally concentrated on the root portion of the lock pin 251.

JP-A-9-314488

  By the way, in the conventional automatic tool changer 201 shown in FIG. 6, as described above, although it has been devised so that the gap amount that can be generated in the connecting portion does not become as large as possible, while the operating portion such as the robot arm is being used. When an excessive moment load is generated at the connecting portion (joint portion) between the male member 204 and the female member 205, the gap between the connecting portions (more specifically, between the male member 204 and the female member 205) becomes large. Therefore, it may cause a positional shift in various operations such as welding. That is, when the gap amount that can occur between the male member 204 and the female member 205 exceeds the allowable range, the various tools attached to the one end portion 205a of the female member 205 are positioned from the target position. Misalignment is likely to occur, and it is not easy to accurately perform various operations such as welding using various tools. Further, if the air pressure is increased to increase the connecting force at the connecting portion, the gap that can be generated between the male member 204 and the female member 205 can be reduced, but a large-scale remodeling is required, which is a reality. Not right.

  In addition, these industrial robots have a long robot arm 2 (see FIG. 1), which has been a cause of the excessive moment load described above. Therefore, it is necessary to reduce the moment load by shortening the overall length of the robot arm 2 as much as possible.

  In the conventional automatic tool changer 201 shown in FIG. 6, in order to reduce the moment load, the axial thickness of the female mold member 205 is increased while maintaining the load strength to the lock pin 251 provided on the female mold member 205. In order to reduce this, it can be considered that the material used for the lock pin 251 is changed to one having higher strength and the diameter of the lock pin 251 is made smaller. However, in general, a high-strength material has a high price, and is difficult to adopt when considering the effect according to the cost. Therefore, in order to maintain the load strength to the lock pin 251 with the conventional material, a considerable thickness L21 is required in the axial direction of the female member 205, and this is a connecting portion between the male member 204 and the female member 205. It was also a cause of excessive moment load.

  Then, an object of this invention is to provide the automatic tool changer which can suppress the gap which arises in the connection part of an automatic tool changer, maintaining the present air pressure.

(1) The automatic tool changer according to the present invention has a protruding portion at one end, and a cam mechanism that can protrude from the inside of the protruding portion to the outside at the protruding portion. A male member to which an operation unit capable of generating a driving force for driving the cam mechanism is detachably attached, a hole at which one of the tools is replaceably attached at one end, and the projection can be inserted; and A female member having an engaging portion that engages with the cam mechanism according to the rotation of the cam mechanism of the protrusion inserted into the hole, and the male member and the female die The member can be connected by engaging the cam mechanism and the engaging portion so that the cam mechanism and the engaging portion are in contact with each other, and the female member has a dispersive surface that can disperse the force acting from the cam mechanism. The dispersion surface; and All ranges arm mechanism and said engagement portion is in contact with, characterized in that face each other across the engaging portion. Here, “facing” means that at least a normal line on the dispersion surface and a perpendicular line in the center of a range where the cam mechanism and the engaging portion are in contact with each other coincide or intersect. including.

  According to the configuration of (1) above, the driving force from the cam mechanism of the male member connected to the female member is obtained by having the dispersion surface capable of dispersing the force acting from the cam mechanism. By passing through the engaging portion and the dispersion surface, the light is transmitted while being uniformly dispersed toward the connecting portion (joint portion) between the male member and the female member. With this driving force transmission method, the male member and the female member are connected to each other with a substantially uniform force on the surface where the male member and the female member are connected. Accordingly, compared to the case where the driving force from the cam mechanism is locally concentrated on the root portion of the lock pin in the female member as in the conventional automatic tool changer, the male member and the female member are It is possible to suppress a gap that may occur in the connecting portion (joint portion) of the automatic switching device, and to withstand a large load applied to the connecting portion of the automatic changer. Thereby, in each tool attached to the one end part of a female type member, it can be made hard to produce a position gap to a target position under work. As a result, in the automatic tool changer, various operations using each tool attached to one end of the female member can be performed with higher accuracy than before.

  Furthermore, according to the structure of said (1), in the whole female type | mold member, the weight at the time of a male type | mold member and a female type | mold member being connected (The weight of the welding instrument etc. which were attached to the front-end | tip of a female type | mold member is included. ). In particular, since the female member has a dispersion surface, the load can be received in a uniformly dispersed state. For this reason, it is possible to receive a load at the engaging portion of the female member without depending on the diameter of the lock pin as in the conventional automatic tool changer. As a result, the axial thickness of the female member, that is, the axial length of the hole formed in the female member can be reduced. Accordingly, the cam mechanism can be moved closer to the other end of the male member, and the axial length of the protrusion of the male member inserted into the hole can be reduced. The thickness of can also be reduced. For this reason, the thickness of the whole automatic tool changer can be controlled more than before. As a result, the overall length of the robot arm 2 (see FIG. 1) is shortened, and the moment load generated at the connecting portion between the male member and the female member can be reduced. Eventually, when each tool is attached to one end portion of the female member and the work is performed, it is possible to further reduce the gap that may occur in the connecting portion.

(2) In the automatic tool changer of (1) above, the female member holds the engagement member at a position that includes the engagement member including the engagement portion and the dispersion surface and surrounds the hole. A holding portion provided for the purpose, wherein the engaging member has a portion in surface contact with the dispersion surface, and the surface contact portion has at least a direction in which a force from the cam mechanism acts. It is preferable to cross.

  According to the configuration of (2) above, the holding portion and the engaging member are brought into surface contact with each other on the surface intersecting with the direction in which the force from the cam mechanism acts, so that the surface contact portion adds from the cam mechanism. The force can be reliably distributed.

(3) In the automatic tool changer of the above (1) or (2), it is preferable that the engaging member is configured to be separable from the female member.

  According to the configuration of (3) above, when the engagement member needs to be replaced due to wear, it is not necessary to replace the entire engagement member and the holding portion (only the engagement member needs to be replaced). Therefore, the parts cost of the automatic tool changer can be reduced as compared with the case where the engaging member and the holding part are configured as a single unit.

It is a schematic block diagram of the industrial robot to which the automatic tool changer concerning this embodiment is applied. It is a perspective view of the male type member and female type member which constitute the automatic tool changer concerning this embodiment. (A) is a front view of an automatic tool changer, (b) is a side view which shows the state which decomposed | disassembled the automatic tool changer into the male type member and the female type member. (A) is a sectional side view showing a state before the male member and the female member are connected, (b) is a cross-sectional view taken along line AA shown in FIG. It is a sectional side view which shows the state with which the male type member and the female type member were connected. It is explanatory drawing which showed the flow of the force which acts on a lock part from the cam mechanism in the automatic tool changer of FIG. It is explanatory drawing for demonstrating the connection operation | movement of the male member and female member which comprise the conventional automatic tool change apparatus, Comprising: (a) is before a male member and a female member are connected. It is a sectional side view which shows a state, (b) is a sectional side view which shows the state with which the male type member and the female type member were connected. It is explanatory drawing which showed the flow of the force which acts on a lock pin from the cam mechanism in the conventional automatic tool changer.

  Hereinafter, an automatic tool changer according to an embodiment of the present invention will be described with reference to FIGS.

(Overall configuration of industrial robot)
As shown in FIG. 1, the industrial robot 100 includes an automatic tool changer 1, a robot arm 2, and a spot welding gun (tool) 3. The automatic tool changer 1 includes a male member 4 and a female member 5 that can be connected to each other. As shown in FIG. 1, the automatic tool changer 1 includes a male member 4 that is detachable from the robot arm 2 at the other end 4b, and a female member 5 that is detachable from the spot welding gun 3 at one end 5a. And is attached between the robot arm 2 and the spot welding gun 3. Although the spot welding gun 3 has a considerable weight, the robot arm 2 having a considerable length can freely move. Therefore, the automatic tool changer 1 connecting them has a great moment load. Will occur.

  The robot arm 2 can supply and exhaust air to and from the male member 4, and a cam mechanism 46 (described later with reference to FIGS. 2 to 4) of the male member 4 according to the air supply and exhaust. ) Is generated to rotate. A plurality of spot welding guns 3 previously attached to the female member 5 are prepared and arranged on a shelf. Of the female members 5 to which the spot welding gun 3 is attached, one female member 5 is selected according to the work, and the selected female member 5 and the male member 4 are detachably connected. By doing so, it is possible to cause the robot arm 2 to perform a predetermined operation.

(Configuration of male member)
As shown in FIGS. 2 and 3A, the male member 4 has an outer peripheral portion 4c formed in a substantially hexagonal column shape, and a protrusion formed in a bowl-shaped substantially hexagonal column shape projecting at one end portion 4a. It has two positioning pins 41 for determining the position of the portion 40 and the female member 5. As shown in FIGS. 3A and 3B, the male member 4 determines the position of the robot arm 2 and the flange portion 42 for positioning with the robot arm 2 at the other end 4b. A plurality of positioning holes 43a for fixing and a fixing hole 43b for fixing the robot arm 2 and the male member 4 are provided. The holes 43 a and 43 b are alternately provided along the circumferential direction of the flange portion 42 at a position surrounding the flange portion 42.

  3B and 4A, the male member 4 includes a cylinder housing chamber 44, an air cylinder 45 housed in the cylinder housing chamber 44, and the protrusion 40. A cam mechanism 46 capable of projecting to the outside, a piston 47 for interlocking the air cylinder 45 and the cam mechanism 46, and each port for supplying or discharging air between the robot arm 2 and the cylinder housing chamber 44 48a, 48b. A part of the air cylinder 45, the cam mechanism 46, and the piston 47 is accommodated in a concave accommodation space 40 a formed in the protrusion 40.

  As shown in FIG. 4A, the air cylinder 45 is formed in a position surrounding the head member 45a, a through hole 45b for allowing the piston 47 to pass therethrough, and the through hole 45b, and is provided at a certain interval. The two expanded diameter members 45c and 45d. In addition, as shown to Fig.3 (a), the air cylinder 45 and the piston 47 are integrated by the fastening members 60, such as a volt | bolt.

  As shown in FIG. 3B and FIG. 4A, the cam mechanism 46 has the protruding portion 40 extended in a state in which the sharpened portion 46a, which is a part of the cam mechanism 46, is inserted between the enlarged diameter members 45c and 45d. When the male member 4 and the female member 5 are connected to each other, the engaging portion 51b of the lock part 51, which will be described later, is supported by the support pin 49 extending in the direction perpendicular to the installation direction. It has an arcuate engaging portion 46b that engages. In the present embodiment, as shown in FIG. 2, a total of three cam mechanisms 46 are provided for each approximately 120 ° angle along the circumferential direction of the male member 4.

  As shown in FIG. 4A, the ports 48 a and 48 b are connected to the robot arm 2 (not shown) via the air tube 61. As a result, air can be supplied and exhausted between the robot arm 2 and the male member 4. The air cylinder 45 and the piston 47 are arranged along the axial direction of the male member 4 in accordance with the driving force accompanying the supply of air to the ports 48a and 48b or the discharge of air from the ports 48a and 48b. The cam mechanism 46 can be rotated around the support pin 49 according to this movement.

(Configuration of female member)
As shown in FIG. 2, the outer peripheral portion 5 b of the female member 5 is formed in a substantially hexagonal column shape like the male member 4. As shown in FIG. 2, the spot welding gun 3 is detachably attached to one end portion 5 a of the female member 5.

  As shown in FIG. 2, the female member 5 has substantially the same shape as the protrusion 40 of the male member 4, a hole 50 into which the protrusion 40 can be inserted, a lock part (engagement member) 51, and A holding portion 52 provided to hold the lock part 51 at a position surrounding the hole 50, and a positioning hole 53 formed at a position corresponding to the positioning pin 41 and into which the positioning pin 41 can be inserted. Have.

  As shown in FIG. 4A, the lock part 51 is detachably attached from the female member 5 using a fastening member 62 such as a bolt. The lock part 51 has an inner surface 51a formed in a substantially S shape in a side sectional view, and a cam mechanism formed on the inner surface 51a according to the rotation of the cam mechanism 46 of the protrusion 40 inserted into the hole 50. 46, an arcuate engagement portion 51b that engages with the engagement portion 46b, and a flat surface that intersects the direction in which the force from the cam mechanism 46 acts, and a dispersion surface 52a, which will be described later, of the holding portion 52 And a flat surface 51c in surface contact. Here, as shown in FIG. 4 (b), the driving force from the cam mechanism 46 of the male member 4 connected to the female member 5 due to the surface contact between the dispersion surface 52a and the flat surface 51c is This is transmitted to the other end surface 5c of the female member 5, that is, the connecting portion (joint portion) between the male member 4 and the female member 5 via the engaging portion 51b and the dispersion surface 52a.

  Here, the flow of force acting on the lock part 51 from the cam mechanism 46 will be described with reference to FIGS. 4 and 5. A white arrow shown in FIG. 5 indicates a vector of the driving force from the cam mechanism 46 of the male member 4 connected to the female member 5. Further, FIG. 5 shows a state where the lock part 51 is virtually separated from the female member 5 (a state where the dispersion surface 52a and the flat surface 51c are not in surface contact) in order to illustrate the flow of force. However, in the actual use state, the dispersion surface 52a and the flat surface 51c are in surface contact.

  Then, if the dispersion surface 52a and the flat surface 51c are in surface contact from the state where the dispersion surface 52a and the flat surface 51c are not in surface contact, for example, the thick solid line in FIG. As indicated by the arrows, the driving force from the cam mechanism 46 can be transmitted while being distributed toward the connecting portion (joint portion) between the male member 4 and the female member 5. As a result, on the connecting surface where the male member 4 and the female member 5 are connected to each other, the driving force from the cam mechanism 46 is distributed and transmitted substantially evenly. From the above, the male member 4 and the female member 5 can be connected to each other with a substantially uniform force evenly on the connecting surface without particularly increasing the air pressure from the air cylinder 45, and the robot arm 2. It is possible to suppress a gap that may occur in the connecting portion of the automatic tool changer 1 when the is operated.

  Returning to FIG. 4A, the holding portion 52 is a flat surface that is formed in a substantially L shape in a side sectional view and intersects the direction in which the force from the cam mechanism 46 acts. It has a dispersion surface 52a on the inner side, which is in surface contact with the flat surface 51c of 51 and capable of dispersing the force acting from the cam mechanism 46. Here, the dispersion surface 52a and the entire range where the cam mechanism 46 and the engaging portion 46b contact each other are disposed so as to face each other with the engaging portion 46b interposed therebetween. In the present embodiment, as shown in FIG. 2, a total of three holding portions 52 are provided for each 120 ° angle along the circumferential direction of the female member 5 at a position corresponding to the cam mechanism 46. Yes.

(Connection operation of male member and female member)
Below, the connection operation | movement of the male type | mold member 4 and the female type | mold member 5 is demonstrated, referring FIG. First, in the initial state shown in FIG. 4A, the positions of the outer peripheral portions 4c and 5b of the male member 4 and the female member 5 are aligned with each other from the robot arm 2 to the male member 4. Air is supplied to the cylinder housing chamber 44 through the port 48a. Then, the air cylinder 45 and the piston 47 are moved in a direction away from the flange portion 42 (in the direction indicated by the white arrow in the drawing) according to the driving force accompanying the supply of air. In association with this movement, the cam mechanism 46 rotates in the direction of the arrow indicated by the thick line in FIG. 4A, so that an arc formed between the sharpened portion 46a and the engaging portion 46b in the cam mechanism 46. The substantially central portion of the surface is maintained in contact with the diameter-expanding member 45c.

  Next, in FIG. 4B, the port from the cylinder housing chamber 44 of the male member 4 toward the robot arm 2 with the protrusion 40 of the male member 4 inserted into the hole 50 of the female member 5. Air is discharged through 48a, and air is supplied from the robot arm 2 toward the cylinder housing chamber 44 of the male member 4 through the port 48b. Then, the air cylinder 45 and the piston 47 move in a direction approaching the flange portion 42 according to the driving force accompanying the supply / exhaust of air. Along with this movement, the contact state between the substantially central portion of the arc surface formed between the pointed portion 46a and the engaging portion 46b and the diameter-expanding member 45c is released, and the cam mechanism 46 is shown with a bold line in the figure. The engaging portion 46b of the cam mechanism 46 and the engaging portion 51b of the lock part 51 are engaged with each other by rotating in the arrow direction indicated by. The engagement restricts the cam mechanism 46 from moving in the direction opposite to the insertion direction of the protrusion 40 into the hole 50, and the other end surface 5 c of the female member 5 is one end of the male member 4. By contacting 4a, the connection between the male mold member 4 and the female mold member 5 is completed.

(Characteristics of automatic tool changer according to this embodiment)
According to the above configuration, the driving force (the white arrow shown in FIG. 5) from the cam mechanism 46 of the male member 4 connected to the female member 5 is applied to the male member 4 and the female member 5. It can be transmitted toward the connecting portion (joint portion) while being distributed substantially uniformly. More specifically, in the case of the conventional automatic tool changer 201 shown in FIG. 6, as indicated by the solid line arrow in FIG. 7, the driving force from the cam mechanism 246 (the white arrow shown in FIG. 7). ) Locally concentrate on the root portion of the lock pin 251, so that the driving force from the cam mechanism 46 is biased at the connecting surface where the male member 4 and the female member 5 are connected to each other. . As a result, if an excessive moment is applied to the connecting portion between the male member 4 and the female member 5, a gap may be generated between the male member 4 and the female member 5. In this regard, according to the above-described configuration described in the present embodiment, the driving force from the cam mechanism 46 is distributed substantially uniformly on the connecting surface where the male member 4 and the female member 5 are connected to each other. Therefore, without increasing the air pressure from the air cylinder 45, the male member 4 and the female member 5 can be connected to each other with a substantially uniform force on the connecting surface without deviation, and the robot arm 2 can be operated. It is possible to suppress a gap that may occur in the connecting portion of the automatic tool changer 1 when being performed. For this reason, in the spot welding gun 3 (refer FIG. 1) attached to the one end part 5a of the female-type member 5, it can make it difficult to produce the position shift with respect to the target position during an operation | work, and, by extension, an automatic tool changer 1, it is possible to perform a welding operation using the spot welding gun 3 attached to the one end portion 5 a of the female member 5 with higher accuracy than before.

  Still further, according to the above configuration, not only the lock part 51 separable from the female mold member 5 but also the entire female mold member 5 when the male mold member 4 and the female mold member 5 are connected. Can receive a load. Therefore, the load strength of the lock part 51 can be maintained without depending on the diameter of the lock pin 251 as in the conventional automatic tool changer 201 (see FIG. 6). As a result, the axial thickness L1 of the female member 5 (see FIG. 4A), that is, the axial length L1 of the hole 50 formed in the female member 5 (see FIG. 4A) is conventional. Thickness L21 (see FIG. 6A). Accordingly, the position of the cam mechanism 46 can be brought closer to the other end 4b side of the male member 4, and the axial length L3 of the protrusion 40 of the male member 4 inserted into the hole 50 (FIG. 4 ( a)) can be reduced from the conventional length L23 (see FIG. 6A), the axial thickness L2 of the male member 4 (see FIG. 4A) is also the conventional length L22 (FIG. 6 (a)). For this reason, the thickness of the entire automatic tool changer 1 can be suppressed as compared with the conventional automatic tool changer 201. As a result, it is possible to reduce the moment generated at the connecting portion between the male member 4 and the female member 5, and when performing work by attaching each tool such as the spot welding gun 3 to one end of the female member 4. In addition, it is possible to further suppress a gap that may occur in the connecting portion.

  Further, since the lock part 51 is configured to be separable from the holding part 52, when the lock part 51 is worn and needs to be replaced, it is not necessary to replace the entire lock part 51 and the holding part 52. Therefore, the parts cost of the automatic tool changer 1 can be reduced as compared with the case where the lock part 51 and the holding part 52 are configured integrally.

  As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  In the above-described embodiment, an example in which three cam mechanisms 46 are provided at approximately 120 ° angles along the circumferential direction of the male member 4 is described. However, the present invention is not limited to this angle. The number of cam mechanisms 46 provided on the member 4 can be changed. Similarly, the example in which the holding portion 52 is provided at approximately 120 ° angles along the circumferential direction of the female member 5 at the position corresponding to the cam mechanism 46 has been described. However, the holding portion 52 is not limited to this angle. The number of holding parts 52 provided on the female member 5 can be changed as appropriate.

  In the above embodiment, an example in which the cam mechanism 46 is rotated by supplying and exhausting air between the robot arm 2 and the male member 4 has been described. However, the present invention is limited to this embodiment. Instead, the cam mechanism 46 may be rotated by supplying or discharging a liquid between the robot arm 2 and the male member 4, or by a drive mechanism using a motor, a solenoid, or the like. Alternatively, the cam mechanism 46 may be rotated.

  In the above-described embodiment, the example in which the flat surfaces 51c and the dispersion surfaces 52a are formed at positions intersecting the direction in which the force from the cam mechanism 46 acts has been described. However, the positions of the flat surfaces 51c and the dispersion surfaces 52a are described. Can be changed according to the direction in which the force from the cam mechanism 46 acts, and may be formed at any position as long as it intersects the direction in which the force from the cam mechanism 46 acts.

  In the above-described embodiment, the example in which the surfaces 51c and the dispersion surface 52a are brought into surface contact by forming the surfaces 51c and the dispersion surface 52a in a flat shape is described. The dispersion surface 52a may be formed not only in a curved shape, but also in an uneven shape.

  Moreover, in the said embodiment, although the outer peripheral part 4c of the male type | mold member 4 and the outer peripheral part 5b of the female type | mold member 5 were described about the example formed in substantially hexagonal column shape, it is not limited only to this shape, You may change the shape of each outer peripheral part suitably.

  Moreover, although the example which forms the protrusion part 40 of the male type | mold member 4 in the bowl-shaped substantially hexagonal column shape was described in the said embodiment, it is not limited only to this shape, The shape of the protrusion part 40 is changed suitably. You can do it. Similarly, the shape of the hole 50 into which the protrusion 40 can be inserted may be appropriately changed according to the shape of the protrusion 40.

1,201 Automatic tool changer 2 Robot arm (operation unit)
3 Spot welding gun (tool)
4, 204 Male member 4a, 204a One end portion 4b, 204b Other end portion 4c Outer peripheral portion 5, 205 Female member 5a, 205a One end portion 5b Outer peripheral portion 5c Other end surface 40, 240 Protruding portion 40a Housing space 41 Positioning pin 42 Flange 43a, 53 Positioning hole 43b Fixing hole 44, 244 Cylinder housing chamber 45, 245 Air cylinder 45a Head member 45b Through hole 45c Diameter expanding member 46, 246 Cam mechanism 46a Pointed portion 46b Engaging portion 47, 247 Piston 48a 48b Port 49 Support pin 50, 250 Hole 51 Lock part (engagement member)
51a Inner surface 51b Engaging portion 51c Flat surface 52 Holding portion 52a Dispersing surfaces 60, 62 Fastening member 61 Air tube 100 Industrial robot 248 Elastic member 251 Lock pin

Claims (3)

A cam mechanism that has a protrusion at one end and can protrude from the inside of the protrusion is provided at the protrusion, and a driving force for driving the cam mechanism can be generated at the other end. A male member to which a detachable operation part is detachably attached;
At one end, each tool is attached in a replaceable manner, and is engaged with the cam mechanism according to the hole into which the protrusion can be inserted and the rotation of the cam mechanism of the protrusion inserted into the hole. A female member having a mating engagement portion;
With
The male member and the female member are connectable by engaging so that the cam mechanism and the engaging portion are in contact with each other,
The female member has a dispersion surface capable of dispersing the force from the cam mechanism acting from the male member toward the connecting portion of the female member;
The dispersion surface and the entire range where the cam mechanism and the engagement portion contact each other across the engagement portion, so that the force from the cam mechanism is distributed via the engagement portion. An automatic tool changer configured to act on a surface. The female member is
An engagement member including the engagement portion;
A holding portion provided for holding the engaging member at a position including the dispersion surface and surrounding the hole,
The engaging member has a portion in surface contact with the dispersion surface;
The automatic tool changer according to claim 1, wherein the surface contact portion intersects at least a direction in which a force from the cam mechanism acts. The automatic tool changer according to claim 2 , wherein the engaging member is configured to be separable from the female member.