JPH0437700Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The invention relates to a chuck device for a shaft-shaped workpiece.
For example, the present invention relates to a chuck device suitable for gripping a camshaft to prevent it from rotating when the camshaft is sequentially conveyed between a plurality of work stations in the machining process of a camshaft for an automobile engine.

Conventional technology For example, the camshaft of an automobile engine is
It has multiple cams to open and close the intake and exhaust valves, and the cam surface of each cam is individually quenched and hardened by Teig treatment, etc., so the quenching process involves multiple cams with torches placed at fixed positions. The working stations are alternately heating and cooling stations. Then, the camshaft is held in a horizontal position by a transfer machine or the like and is sequentially transported in a direction perpendicular to the axial direction, and certain processing is performed at each work station. However, since the cams of the above camshaft are provided with different phases, the camshaft
After being positioned at the original position at the first work station, it is transported to the second work station so as not to shift in the circumferential and axial directions.
When the work station is rotated by a predetermined angle according to the desired cam phase and a certain process is performed, it is rotated back to its original position, and then each work station is rotated in the same manner. transported to.
The camshaft is gripped by a chuck device to prevent it from shifting in the circumferential or axial direction during transportation. Conventionally, chuck devices have a pair of fixed arms installed opposite each other on a mounting frame that is supported at equal intervals and capable of square motion, and a steel ball is inserted into and retracted from the opposing end surfaces of each fixed arm. The steel ball is elastically pressed and held by a coil spring built into the tip of the fixed arm, and when the camshaft is gripped, the coil spring's biasing force The steel balls press against the outer peripheral surface of the camshaft and grip the camshaft.

Problems to be Solved by the Invention According to the conventional chuck device, the steel balls are always urged inward by the strong spring force of the coil spring, so when gripping the camshaft,
Alternatively, if the camshaft is rotated by a predetermined angle according to the phase of the cam while the camshaft is gripped at each work station, a large frictional resistance is generated between the steel balls and the camshaft, which causes severe wear on the steel balls. However, there was a problem of poor durability.

Means for Solving the Problems The present invention was proposed in view of the above-mentioned problems, and includes a mounting frame and a pivot support on the mounting frame that can be opened and closed via a bracket and that are opposed to each other. a pair of gripping claws, a cylinder disposed between the gripping claws and having openings at both ends, and a cylinder inserted into the cylinder so as to be movable symmetrically, and openings at both ends of the cylinder. A pair of pressing bodies protrudes outward from the cylindrical body to press the gripping claws to open and close, and is compressed between the pressing bodies in the cylinder, and applies a weak gripping force to each gripping claw through the pressing bodies by spring force. The spring member has a tip opening into a cylinder chamber, and is selectively activated to apply a strong gripping force to each of the gripping claws through a pressing body using air pressure.

Operation By selectively operating the air pressure feeding means, the gripping force acting on the gripping claws can be adjusted to two levels, strong and weak, by the biasing force of the spring member and the air pressure from the air pressure feeding means. It is.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6. In the drawing, 1 is a camshaft of an automobile engine, and a plurality of cams 3 are provided on the shaft portion 2 of the camshaft 1 in different phases for opening and closing intake and exhaust valves, and a positioning cam 3 is provided on one end surface of the camshaft 1. A keyway is formed. Since the cam surfaces of the cams 3 of the camshaft 1 are individually hardened, the hardening process involves a plurality of work stations a, b, etc. each having a torch or the like placed at a fixed position, that is, a heating station and a cooling station are alternately used. The camshaft 1 is sequentially conveyed in a direction perpendicular to the axial direction while being held in a horizontal position, and is moved to each work station a, b...
Certain processing is performed. 4 and 5 are centers for supporting the above-mentioned camshaft;
5 is attached to each of the work stations a, b... so as to face the tip surfaces of a main spindle 6 and a tailstock spindle 7, which are arranged so as to be able to move inwardly and outwardly. A key 8 is formed which fits into and locks into the keyway of the camshaft 1. Reference numeral 9 denotes a transfer bar for conveying the camshaft 1, and this transfer bar 9 is provided along the conveyance direction of the camshaft 1. Reference numeral 10 denotes a substantially T-shaped mounting frame that is attached to the transfer bar 9 and held upright, and has a horizontal plate portion 10b at the upper end of the vertical plate portion 10a. . . . and is configured to perform square motion between adjacent work stations by the operation of the transfer bar 9. Reference numeral 11 denotes a chuck device installed on the horizontal plate portion 10b of the mounting frame 10. In the chuck device 11, 12a, 12a, 12b, 1
Brackets 2b are oppositely provided on the horizontal plate portion 10b of the mounting frame 10, and 13a and 13b are pivotably supported on the brackets 12a, 12a and 12b, 12b via pivots 14a and 14b, respectively, so as to be openable and closable. With a pair of gripping claws, each gripping claw 13a,
13b has claw portions 15a, 15b for gripping the shaft portion 2 of the camshaft 1 formed on the upper side of the pivot portion, and abutment pieces 16a, 16b integrally formed on the lower side. Reference numeral 17 indicates gripping claws 13a, which are located on the horizontal plate portion 10b of the mounting frame 10 and are opposed to each other.
A cylinder tube 17 is installed between the abutment pieces 16a and 16b of the cylinder tube 13b, and openings 18a and 18b are formed at both ends of the cylinder tube 17. 19a,1
Reference numeral 9b denotes a pair of pressing bodies inserted into the cylinder chamber 20 of the cylinder tube 17 so as to be symmetrically movable and facing the abutment pieces 16a, 16b of the gripping claws 13a, 13b. protrudes outward from both end openings 18a, 18b of the cylinder tube 17, presses the abutment pieces 16a, 16b, and opens and closes the gripping claws 13a, 13b. The pressing bodies 13a, 13b open the opposing inner end surfaces of the cylindrical parts 21a, 21b, and
Conical projections 22a, 22 on the outer end surfaces of a, 21b.
b is formed. Reference numeral 23 denotes a spring member such as a coil spring that is removably compressed between the pressing bodies 19a and 19b in the cylinder tube 17. The spring force of the spring member 23 causes the pressing bodies 19a and 19b to be compressed.
is pressed to apply a weak gripping force to the gripping claws 13a and 13b. Reference numeral 24 shown in FIG. 5 is an air pressure feeding means that is selectively operated, and this air pressure feeding means 24 is
For example, the air compressor 26 is connected to the pressure pipe 27.
The tip of the pressure-feeding pipe 27 is connected to a substantially central portion of the cylinder chamber 20 of the cylinder tube 17, and the air pressure of the air fed from the air compressor 26 is used to push the air through the pressing bodies 19a and 19b. A strong gripping force is applied to the gripping claws 13a and 13b. 28a and 28b are stoppers for adjusting the degree of closing of the gripping claws 13a and 13b;
8a and 28b are horizontal plate portions 10b of the mounting frame 10;
A wall body 30 with screw holes 29a and 29b formed above and outside the gripping claws 13a and 13b.
a, 30b are installed and fixed, and each wall body 30a, 30b is
The gripping claws 13a, 13b are attached to the screw holes 29a, 29b.
The adjusting bolts 31a, 31b are screwed in oppositely to the abutting pieces 16a, 16b, and the adjusting bolts 3
Nuts 32a and 32b are screwed and tightened into nuts 1a and 31b, respectively. Reference numerals 33a and 33b denote support receivers having an L-shaped cross section and provided on the horizontal plate portion 10b of the mounting frame 10 and oppositely on both sides of the chuck device 11. , 34b have notches 35a, 35 for supporting both ends of the shaft portion 2 of the camshaft 1.
b is formed.

Next, the operating procedure of the device of the present invention will be explained as follows.

As shown in FIG.
When the camshaft 1 is supplied and held in a horizontal position, the main shaft 6 and the tailstock shaft 7 move inwardly, and the camshaft 1 moves toward the center 4 of each shaft 6, 7.
At the same time, the key 8 of the main shaft 6 is fitted and locked into the key groove on one end surface of the camshaft 1, and the camshaft 1 is positioned and held at its original position. At this time, the mounting frame 10 is located at the lowering end of the first work station a, and the air pressure feeding means 25 of the chuck device 11 is in an inactive state, so the pressing bodies 19a and 19b in the cylinder chamber 20 are Due to the spring force of the spring member 23, the gripping claws 13 are moved outwardly.
a, 13b, and a weak gripping force is applied to the claw portions 15a, 15b of the gripping claws 13a, 13b. Therefore, the mounting frame 1
0 rises and is located at the rising end, the gripping claws 13a, 13b of the chuck device 11 are easily pushed open by the shaft portion 2 of the camshaft 1 during its rise, and the camshaft 1 is gripped with a weak gripping force. In this way, the camshaft 1 is gripped by the weak gripping force of the gripping claws 13a and 13b, so that the camshaft 1
is rotated by a predetermined angle according to the desired phase of the cam 3 while being gripped by the gripping claws 13a and 13b, and
Even if the cam surface is rotated back to its original position after a certain treatment, the frictional resistance between the gripping claws 13a, 13b and the camshaft 1 is small, and the gripping claws 13
It is possible to prevent the claw portions 15a and 15b of a and 13b from being worn out. When the camshaft 1 is thus positioned at the original position again, the air compressor 26 of the air pumping means 25 is operated, and air is pumped into the cylinder chamber 20 via the pressure pipe 27. Then, the pressing bodies 19a, 19b are pressed by the air pressure in the cylinder chamber 20 and move outward, and the abutting pieces 16 of the gripping claws 13a, 13b
Press a, 16b. This pressing body 19a, 19
By pressing b, the gripping claws 13a, 13b are
The camshaft 1 is rotated in the closing direction about the fulcrums 4a and 14b, and the camshaft 1 is gripped by a strong gripping force acting on the claws 15a and 15b. When the camshaft 1 is gripped with strong gripping force by the gripping claws 13a and 13b, the support frame 1 is moved by the operation of the transfer bar 9.
0 moves horizontally in a straight line, and the camshaft 1 is transported to the second work station b. At this time, the camshaft 1 is held with a strong gripping force, so
Rotation during transportation can be reliably prevented. Then, when the support body 10 is held at the rising end of the second work station b, the main shaft 6 and the tailstock shaft 7 arranged in the second work station b move inwardly, and the center 4, 5, the camshaft 1 is supported in the original position. When the camshaft 1 is thus held at the second work station b, the air pumping means 25 stops operating, and as a result, the pressing bodies 19a and 19b are pressed by the spring force of the spring member 23, and the camshaft 1 is It is gripped with a weak gripping force of the gripping claws 13a and 13b. After that, when the support frame 10 is lowered, the camshaft 1 is moved by the gripping claws 13a, 13b.
The support frame 10 is easily pulled out from between the claws 15a and 15b, and after reaching the lower end, the support frame 10 moves toward the first work station a, and passes through the lower end of the first work station a. held at the rising edge. Repeat the same operation below.

In the above embodiment, a camshaft is used as the shaft-shaped work to be gripped by the chuck device 11, but the present invention is not limited to this, and can be applied to all shaft-shaped works. Furthermore, in the above embodiment, the case where the quenching process is performed on the camshaft 1 supported by the centers 6 and 7 while the camshaft 1 is being held by the gripping claws 13a and 13b has been described. , b... may be made to wait at the descending end. Further, although a spring member 23 is provided in the cylinder chamber 20 of the chuck device 11, this spring member 23 is eliminated and the air pressure from the air pressure feeding means 25 is used to grip the shaft-like workpiece only while it is being transported. You can do it like this.

Effects of the invention The present invention adjusts the gripping force acting on the gripping claws into two levels, strong and weak, by selectively operating the air pressure feeding means, using the biasing force of the spring member and the air pressure from the air pressure feeding means. can do. Therefore, if the chuck device according to the present invention is used, for example, in a device that conveys a camshaft during a hardening process in which the cam surfaces of cams with different phases of the camshaft are subjected to a quenching process, etc., it is possible to During the hardening process, it is possible to grip with a weak gripping force, so there is no large frictional resistance between the gripping claws and the camshaft, which prevents wear on the gripping claws and significantly improves durability. . Furthermore, since the camshaft can be gripped with a strong gripping force during transportation, it is possible to reliably prevent the camshaft from shifting in the axial and circumferential directions during transportation.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of the chuck device according to the present invention. Fig. 2 is a schematic front view of a conveyance device to which the device of the present invention is applied, Fig. 3 is a cross-sectional view showing how the gripping claws are pivoted, Fig. 4 is a side view of the support receiver, and Fig. 5 FIG. 6 is a partial cross-sectional explanatory view showing the air pressure feeding means, and FIG. 10...Mounting frame body, 12a, 12b...Bracket, 13a, 13b...Gripping claw, 17...Cylinder tube, 18a, 18b...Opening part, 19a, 1
9b...pressing body, 23...spring member, 25...air pressure feeding means.

Claims (1)

[Scope of utility model registration request] a mounting frame, a pair of gripping claws that are pivotably supported on the mounting frame so as to be openable and closable via a bracket, and are disposed between the gripping claws, and
A cylinder tube having openings at both ends; a pair of pressing bodies that are fitted into the cylinder tube so as to be movable symmetrically and protrude outwardly from the openings at both ends of the cylinder tube to open and close gripping claws by pressing; A spring member is compressed between the pressing bodies in the cylinder and applies a weak gripping force to each gripping claw via the pressing body by spring force, and the spring member has a tip opening into the cylinder chamber and is selectively actuated. and air pressure feeding means for applying a strong gripping force to each of the gripping claws via a pressing body using air pressure.